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MG MGF Technical - make mg go fast !
| there seems to be a lot of different ways to get the standard mgf upgraded - what is the best and cheapest way to upgrade the performance of my mgf so that it reduces 0-60 time (to better than vvc level ?) i dont fancy the idea of some smug clio (172) driver beating me at the lights ! any ideas to what to get, where from, how much etc would be greatly appreciated ta ! Steve S8 STE |
| steve brown |
| WARNING: PERFORMANCE UPGRADES ARE NOT CHEAP Okay, now we've said that, there is plenty you can do, depending on your budget and your aspirations. Performance goodies follow the law of diminishing returns: to get more than 20 bhp requires the expenditure of progressively more cash with progressively less output for your pains. The cheapest and easiest way to release an extra 8- 15 bhp from your MGF is to buy a performance cone filter. See my web site for power curves (http://go.to/mgfgallery). Good value for money this @ around 0.1 bhp per pound sterling spent. This is the highest return for your maoney of ANY upgrade. I have gone for a K&N 57i cone and cold air inductio kit. Costs between 80 to 100 pounds. Next modification is to change the exhaust. The current edition of MG World contains information on these systems. For your money (around 380 pounds) you get a small gain in power and torque. Value for money quotent is at BEST 0.01 bhp per pound (usually considreably worse). The above two mods can have insurance implications- so do check with your insurer. Peter Best put no additional loading on my policy for these items on my car. Next up on the money-pit-performance-add-on-escalator is head work. There are a number of companies retailing re-ported heads with big claims for power. Upto say, 20 bhp on a 1.8MPi head for an outlay of 2-3,000 quid. That bhp per pound performance quotent slips again. Bigger gains can be had- but usually entail the strengthening of the bottom end. Once you've done that, you can look into turbo charging or supercharging. Either conversion will cost at least 6 thousand pounds and net you 40 bhp- but importantly you get a significant torque gain. This is a far from complete summary of what is available for the K-series engine. Fact is the options in terms of throttle bodies/ injestion systems is massive, and you can flush away as much cash you can throw at it. Point is, be objective. If you really want a seriously faster car than the MGF, then consider a different vehicle. It will be cheaper to run (insurance, petrol consumption), be well developed and reliable, and won't loose you all your investment come resale time. Conclusion: The only cheap bolt on performance enhancing add-on is an air filter. A filter + a well choosen exhaust can endow your 1.8MPi with up to 135 bhp on a good day with a torque curve better than a VVC at the low end of the rev range. To beat a VVC, buy a VVC. IMHO. HTH Rob |
| Rob Bell |
| What about weight reduction? I assume there isn't much that can be removed/replaced with lighter material, or am I wrong? Ingemar |
| Ingemar Jansson |
| Steve, I agree with Rob. I have recently driven an MGF with a 160bhp 1.8i engine. Its got modified head and a new ECU and costs £1999 plus VAT plus fitting. Fitting is a two day job so allow another £400 plus VAT. The car also had a fancy airbox, sports exhaust and a close ratio gearbox. Add another £700 for the first 3 items, don't know yet what the gearbox costs. Total so far £3,500 inc VAT - thats without the gearbox. The thing is it didn't feel a lot quicker than my VVC with its K&N and sports exhaust. Conclusion, a 1.8i owner would be better buying a VVC and spending £500 on a filter and exhaust. The 'conversion' would probably be cheaper, and a VVC would be more economical, easier to insure and easier to sell on. Probably not the answer you wanted to hear. Paul P9 VLS |
| Paul |
| Steve You could also try having the CAMS changed to a pair of fasted road cams like The Piper Fasted Road Cam. Piper cliam an extra 15BHP for their cam but I feel that this might be A sales pitch. I believe it would be in the region of about 10BHP. Note that it is really only worth changing the CAMs after you have fitted a sports exhaust and a K&N filter. If you change the cams, Exhaust and inlet filter you could expect the same bhp as for the VVC which is 145 bhp. Also note that the VVC has a different gear box and that also contributes to the claimed 0.60 of 7 seconds. You could try to contact Moto Build www.motobuild.com for the cam converstion. There is also a Icon unit made by Super Chips but there has been several Engines that have been damaged using this so I would avoid it. |
| Steve |
| >> There is also a Icon unit made by Super Chips but there has been several Engines that have been damaged using this so I would avoid it. << Steve, several engines? I am thinking of chipping my car. I was only aware of Dirks problem - can you advise of the others? I do know of two F owners who have had no problems with their chipped cars, and Nick from Gillingham has had his car chipped with no faults. Paul P9 VLS |
| Paul |
| Paul >> Steve, several engines? I am thinking of chipping my car. I was only aware of Dirks problem - can you advise of the others? << The information came from a thread a while ago. From memory. Mike Bees stated that the Icon unit advance the timimg to give more torque. This can lead to pre ition which could burn a hole in the piston. I like you, am also interested in an Icon Unit but am worried that it will damage the engine. It is a catch 2 situation. If you have the fast road cams fitted then the ignition can benefit from having the igition advanced, the question is by how much. Get it wrong and you will get burnt holes in your pistons. Very expensive repair. |
| Steve |
| Paul and others, You may already know this but there is an alternative plug in unit that plays with the ignition timing from Racelogic www.racelogic.co.uk The unit is called the V-SAM and is advertised as being for all K series. I quote from the advert in Motoring News this week... K Series power upgrades. The V-SAM from Racelogic simply plugs into the existing loom of your Rover K-series engine, and re-programs the ignition for more torque and power. If you use quality fuel you can gain 6 to 8 bhp over standard. DIY fitment takes 2 minutes and there is a 30 day money back guarantee. Lotus Elise, Caterham, MGF, all K-series Rovers £195 plus vat Programming kit for above (Windows software and lead) £150 plus vat I will make one comment and that relates to 'quality fuel' which I read as 98RON expensive unleaded. The initial cost may be low in terms of what other mods cost, but there is an ongoing additional cost relating to the fuel used and this will over a long term period add considerably to the running costs. It's a pity that this couldn't be a device like SAAB's APC system that detected fuel quality and adjusted engine management control to suit the fuel. But then again it would be super expensive for just a max of 6 to 8 bhp. (claimed) Any takers please let us know how this device fares. Rog |
| Roger Parker |
| Answered my own question by visiting the updated site from when I was last there. Fuel quality refers to the cheap cr-p that some unknown brands are. It says that the device is designed for use with normal or super unleaded fuels. Rog |
| Roger Parker |
| Thanks Rog, wasn't on Mr. Andrews side (the k-engine tuner) a nearly equal replacement described ? Anyway, a good price .. who tries it at first (Dirkie, not you !!) dk |
| Dieter |
| I have to say, I think anyone who chips there engine must have more money then sense. Do you really think a bunch of blocks working out of some foul little shed in the middle of nowhere, are clever enough to get more power RELIABLY out of an engine than the manufacturer who has had 10s possibly hundreds of people doing the same thing over many years on an engine that they designed. I grant you it is possibly, but surely very unlikely. I would not risk an engine like Dirk's to find out! If a quick fiddle with the program in ECU could deliver more power RELIABLY, surely Rover would be delighted to bring this to the market as either part of the product's natural development or as a hugely over priced upgrade! On the same tack, I understand that the Rover ECU can be changed to run on the assumption that you will only use 98 octane petrol. Is this true and what is the effect. I know everyone says that Super Unleaded has no efect on the F and only on your wallet, but I have to confess, that whenever I drive in France I always slop this stuff in and am sure I can feel a diffrence. Cheers Patrick |
| Patrick |
| FAO Steve, Essex. Motobuild fitted my fast road cams and vernier pulleys, I would agree that with other standard items you might only expect about 10Bhp gain. However, as you stated that by having the other perfomance ancilleries fitted as i have done, i.e. K&N, Supersports Exhaust etc. the cams give a good 15Bhp+ gain. I can confirm that with all the bits costing just £1500 in total. the output i have acheived is between 155 and 160Bhp depending on humidity, air temperature and altitude! And all without even removing the head or intake manifold. Nick R3 NPH |
| Nick |
| >I can confirm that with all the bits costing just >£1500 in total. Nice and very good to know.... Now I know what I am working for <grin> >the output i have acheived is between 155 and 160Bhp >depending on humidity, air temperature and altitude! These are figures for the VVC right. Any idea how these mods will have an impact on the power given by an 1.8MPi. >And all without even removing the head or intake >manifold So they won't be touching the head gasket? Erik (hmmm... what will be next) PS: adding a cat-bypass should give your car another 2bhp. |
| Erik |
| It is a 1.8Mpi <g> not a VVC!!! Nick |
| Nick |
120Bhp (standard) +12Bhp (K&N and exhaust) ------ 132Bhp 155Bhp (with modified cams) -132Bhp (without modified cams) ------- 23Bhp !!! Could the implementation of the other cams result in an increase of 23Bhp and more? What's the impact of this modification on topspeed and acceleration times? I know, a whole bunch of questions..... Cheers, Erik |
| Erik |
| I know a lot of you probably don't think i'm being truthful with the claims i am making about the mods on my F. But i've had it dynoed at two different rolling roads and the figures speak for themselves. In answer to Eriks last question, yes rev range is greater and peak power is at 5800 rpm giving a satisfying 130Bhp at the wheels (some simple maths using factory figures gives the projected flywheel figures). I still haven't managed to measure the 0-60, can't seem to operate a stopwatch and drive at the same time! Nick |
| Nick |
| Hi Nick Do you have those power curves? If so are they on line? From what you describe you should be congratulated for achieving so much on comparatively little outlay- nice work. The 23 bhp with filter, cams, exhaust and chip isn't perhaps so surprising given that the engine breathing has been improved so much. I would speculate that by some very simple modifications to the head to increase the size of the inlet/ exhaust tracks would likely to net you even more power for comparitively little effort. Still- it is nice to know that there is alwys something extra to play with at a later date! My question is really based on the info you have already offered- excllent bhp- what sounds like much improved top end breathing... is the engine now very peaky? Cams traditionally result in lumpy idle, and comparatively little low end torque- is this the case with your engine? Not that this is a bad thing, but some prefer more torque. Cheers Rob |
| Rob Bell |
| When you add Fast Road Cams to the engine. It causes the engine to act in a similar why to the VVC. in that it opens the valves for longer and keep them open longer this means that the K&N can work better in getting in more of the fuel in and the Sports exhaust can work for longer in getting out the gasses. The thoery is additive. You know longer get 12bhp from the K&N plus exhaust but more as there are now in a position to do more. Nick. I was thinking of fitting cams with the icon unit. Did it in your opion make much difference to the acceleration. I have to admit when I fitted the K&N plus SP exhaust I was not really immpressed with the difference, just more noise, which I like but not much power increase (all fitted in same day). I do not want to go potty but would like to think that if I spent a £1000 on this that it would put a smile on my face. |
| Steve |
| >> Do you really think a bunch of blocks working out of some foul little shed in the middle of nowhere, are clever enough to get more power RELIABLY out of an engine than the manufacturer who has had 10s possibly hundreds of people doing the same thing over many years on an engine that they designed. I grant you it is possibly, but surely very unlikely. << Patrick, You obviously havent seen pictures of the Superchips factory!!! Anyway, given my experiences with Rover and Techspeed, and what that latter can do for suspension and gearchange, (that Rover are seemingly unable to do) I would put my money on the bunch of blokes in a shed in the middle of nowhere every time. They have more passion and interest in the car than you will find in any MG dealer! More questions, It seems from whats been said above that fast road cams would be a good idea if your going to have the engine chipped. Will add to the power and reduce the risk of burnt pistions. Can these be fitted to a VVC engine? If so how much dosh? Nick, you have got a chip in your engine haven't you? Did you dyno you engine before and after fitting to see what additions the installation of the chip gave? If so what were the results? What other bits had been fitted at the time? Sorry for the barrage of questions, thanks in anticipation of the replies. Paul P9 VLS |
| Paul |
| I seem to recall one specialist planning to modify the VVC cam so the mechanism is kept. That was over a year ago and nothing else has been said or released [to my knowledge]. Therefore you are in a situation whereby you ditch the VVC and standard VVC MEMS. You have the advantage of a better head design... but is this the way you want to go? Might as well have bought an MPi in the first place. Rob |
| Rob Bell |
| >> I would put my money on the bunch of blokes in a shed in the middle of nowhere every time.<< Anybody seen the latest adverts from Hewlett Packard?? Ted |
| Ted Newman |
| Hi Paul, Didn't mention the chip because everyone seems to be slating it. BTW I've been to superchips and there set up is by no means anything like hewlitt packard <g>. No, unfortunatley i couldn't test the car before and after the ICON was installed as their rolling road was being calibrated at the time.(it was programmed on the fly via notebook PC) But they assured me that the last one they did which had an SP supersports and no other mods did give a 12Bhp improvement(doubt though if this was at wheels). Anyway, i did make sure that it reprogrammed after having the cams done to make sure it was still within acceptable ignition parameters. Cheers Nick |
| Nick |
| FAO Steve, Regards overall sound and feel etc. Cams give a much deeper growl through intake and exhaust, the engine seems punchier, top speed- not made it yet although i have allegedly been to 140 and there was still more to go! email if you want a spin before spending any money Nick@lockandsafe.co.uk |
| Nick |
| >Hewlett Packard *g* a company, back to the roots... (if you mean the same advert as I) -shed in the middle of nowhere- Anyway, looking at Pauls and Patricks message from my humble side. (if allowed) Patrick I know from my experiance of the car industry that any innovation that was designed after introduction of the product is nearly impossible to introduce 'on the fly' later. A simple looking mirror for instance needs app. 3 years of development and introduction to the whole car. All changes after that time only apply COSTS. Because of this reason pre-studies and analysis on possible failures take place at early design phase. (a change of that FMEA costs too) Often the manufacturer is not very satisfied hisself with the end-result, but what should he do ? Repeat the whole process from the beginning ? Impossible, who shall pay that ? So, as Paul wrote. Small special ranges can be probably improved. But as written on the other thread ... out of manufactures warranty and on the own risk :) dk PS... I'll be one of the last (just before Patrick does) who changes anything at the engine :) |
| Dieter |
| fao, Paul, Droitwich I have just been to my rover dealer, they have offered my £14,300 in p/ex for a new VVC but i would still have nearly £7,000 to pay - However, if i wanted to buy a V reg (pre-registered) they would give me £12,700 !?!?!? - but still leaving a £5,500 balance i definitely think a new exhaust and other bits is more cost effective than a new vvc. |
| steve brown |
If it's acceleration rather than top speed you are after why do more people not switch to the low ratio box that's available? It's easy to get hold of from Lotus dealers. Why not MG? This costs around £1100 and I know for a fact that GuyP of MG fame has one fitted. I think I saw it in the B&G brochure. MPi drivers could change the final ratio only at a much reduced cost. I wonder how that would drop the MPi's 0-60 time. If I could, I'd go for a VVC with this box fitted. Yum. P. |
| Paul |
| I have to agree with Paul: changing the gear set makes a good deal of sense. The in gear times will fall, the car will feel a good deal more responsive; the only disadvantage is cruising refinement. It depends on your priorities. Brown and Gammons do indeed have this option listed in their current catalogue. Something to consider- but not if you enter your car for sprints and hill climbs! (Illegal under MGFAT regs). Changing the gear set also makes sense if the power delivery is rather peaky in nature. Whether a re- cammed engine would fall into this category I am not sure (Nick?) I would need to try such a car out, or at least see the power/torque bands. So many toys to play with! ;o) Rob |
| Rob Bell |
| Nick wrote: >Didn't mention the chip because everyone seems to be >slating it. BTW I've been to superchips and there set >up is by no means anything like hewlitt packard <g>. So you are reaching the 155-160bhp with the use of: - K&N - SP Supersports - Chip (ICON) - Fast road cams Correct me if I am wrong..... Thanks, Erik |
| Erik |
| Hi Erik, Spot On. BTW the K&N is the panel type with cool air collected from the side intake. Rob, I agree, 1st could do with being a bit higher and maybe shove 2nd, 3rd and 4th up a bit and if they were all evenly spaced 5th could stay the same as it is. Although at the moment there is a massive difference between 4th and 5th as you already know. At the moment i can't justify the outlay for this next stage in improvements :( Nick |
| Nick |
| Missed this one; Lumpy Idle? No, tickover is fine. low end torque seems not to have changed much, it really gets in to its own over 3500 rpm and power rises steadily to 5800 although due to the naff gears it's just as well to go to 6500 before dropping. As i'm not much of a techy i don't have graphs to show anyone, but Rob, your more than welcome to play if you like, perhaps we should meet. Nick |
| Nick |
| That sounds very promising Nick. Yes, perhaps we could get together some time- the 'team' (organised by Paul Sharpe) is planning a rolling road trip some time in the near future- something to consider perhaps chaps? Interesting to read that the peak occurs @ 6,500 rpm- this suggests [to me anyway] that there may be more to come, should you want to persue things futher. The reason for suggesting this is that the VVC engine power peaks at peak rpm (7,250)- and is linear to that point with no evidence of drop-off (reference- VVC cone powergraphs on http://go.to/mgfgallery). Other than the VVC mechanism itself, the major difference between MPi and VVC as you know is valve sizes... Rob |
| Rob Bell |
| Am I wrong? It is just my thought. Before I upgrade the performance of my F so that it reduces 0-60 time, I should upgrade my brake first. So, there are my steps: 1, Upgrade to 16 inch rims. 2, upgrade the brake, 3,finally upgrade the power. Correct me if I'm wrong. I'm doing like that. Don. |
| Don Liang |
| Don, it sounds to me like the more logical route to go, and the safest. did you make a choice re. brakes ? Are you gonna put big disks that only fit into 16" rims ? Fabrice |
| Fabrice |
| Don- you are ABSOLUTELY right- improve the handling and the brakes first and always before significantly increasing the engine's performance. I think that is what everyone here does- important safety points like this should not be ignored. Very sensible to bring up the point Rob |
| Rob Bell |
| I echo your agreement, Rob. This was the second mod which i carried out after fitting the exhaust. The standard braking is just that 'standard' and cannot be relied on for heavy punishment. Nick |
| Nick |
| I don't agree for the fully 100%. It makes sense if you're driving faster (in the same circumstances as before) because you've got more power. To make itmore clear, an example: ---1----------- circumstances: traffic, weather, driver, ... speed: 120km/h and 120bhp ---2----------- circumstances: traffic, weather, driver, ... (same as in 1) speed: 120km/h and 160bhp Why should I need a brake upgrade if I am in situation 2 ??? ---3----------- circumstances: traffic, weather, driver, ... (same as in 1) speed: 160km/h and 160bhp Doesn't it make more sense to slow down to a reasonable 120km/h, instead of fitting better brakes? Look at it in this way: - Instead of fitting airbags, cars should be equiped with knives. - Don't place the fueltank somewhere safe (between the two rear wheels), but mount it on the front bumper. Who will be speeding when it isn't really safe ??? |
| Erik |
| Does anybody know anything about he supercharger that Steve Parmer sell (as in the SP Cheetah) It looks good on papare with a huge increase in power, (around 200hp) but i can't beleive that it does any good to the engine. As far as i can tell nothing much on the engine is changed when they add the supercharger. |
| Matt |
| From my experience with London cars the cheapest and easiest way of making you car go fast is to fit a whippy aerial with a magnetic base onto your boot lid. It also has the advantage of making all traffic lights appear green, people on zebra crossings to disappear and traffic on main roads give way when you leave side turnings and I almost forget people on two wheels turn into aviators! Ted:-) |
| Ted Newman |
| Matt >>Does anybody know anything about he supercharger that Steve Parmer sell (as in the SP Cheetah) It looks good on papare with a huge increase in power, (around 200hp) but i can't beleive that it does any good to the engine. As far as i can tell nothing much on the engine is changed when they add the supercharger. << IMO it will put too much strain on the engine. All that is done to the engine is the Conrods are shortened to lower the compression ratio in the engine. I think that the components in the engine will not last very long especially if the car is driven hard. |
| Steve |
| What would need doing to the engine to help it stand up to the supercharger, and is it worth it? |
| Matt |
| >>What would need doing to the engine to help it stand up to the supercharger, and is it worth it? << To get some idea have a look at the BBR GTi web site- and look at the technical specifications for the full house turbo conversion (URL: http://www.bbrgti.demon.co.uk/) If you look at the cost of this conversion, you'll understand whether it is worth the effort or not. BTW Matt, under what circumstances would the conversion be worth it? If monetary, then IMO definately not. If you must keep your MG and you want to go seriously faster, then the tables are turned. Your choice. Erik, I understand the point you are making regarding brakes, but with more power you are more likely to be going faster, and braking more often and with more effort. On balance, the only sensible way forward with performance tuning is to upgrade handling and braking before serious engine upgrades. Rob |
| Rob Bell |
| In all honesty Rob i know damn well that its not worth upgrading the car, financially its like flushing money down the toilet. But the fact is i love the car but i want something abit quicker than your average GTI and at present it isn't. I could get a faster car, but it wouldn't be an F, i like only having two seats and nothing els eand i love the handling and feel of it, so its a dilema what to do. Do the brakes and Handling NEED upgrading, i reckon they are good enough for a reasonable increase in power. We aren't exactly talking about putting a V8 in a fiesta |
| Matt |
| Re: BBR GTi, 305Bhp @6800 rpm!!!!!! That's outrageous. Nick |
| Nick |
| Hi Matt, yeah, I guessed you knew the score <g>. You've already got the brake mods (Mike Satur) and upgrades to performance tyres. If I were you, I'd consider lowering the car a little more- but that decision is dependant upon how many obsticles you have to transverse in your daily drive. Regarding performance, then it is a question of how much quicker you want to go, what route you wish to take (loose weight or gain power) and how civilised the end product. Fact is the MGF is an incredibly easy car to live with- and that is part of the car's charm. Personally I'd try to avoid doing anything that significantly undermines the car's character. And this will probably rule out significant weight loss as a performance augmenting option. So, extra power it is. You have a VVC, and that puts you in the same boat as Paul Sharpe, a difficult place to be in terms of performance options. The VVC mechanism puts a psychological barrier in the way of head modifications in the same direction as Nick's fascinating sounding project. Furthermore, there is no point in going for a mod that costs alot but yields very little extra over the standard (and still excellent) VVC. If I were in your position, and I had a couple of grand to spend on the project, then I'd be tempted to go for the controversial option. The TurboTechnics (nee SP Performance Cheetah) conversion is bolt on, and bolt off. The newer version uses the standard MEMS. Therefore, when you come to sell the car, you unbolt the supercharger, and sell your car as standard. You'll probably get as much for the VVC as standard as the VVC + supercharger. And then you could sell the 'charger separately to an increasingly receptive second hand market. I can't comment on engine longevity with the conversion, but the worst that could happen (IMO only) is that the weakest point would let go first- the head gasket. And that is no sweat for MG franchised garages these days. Yes, I think that is the way I would go- after seeking assurances from Turbo Technics and reading their technical information. HTH <g> Rob |
| Rob Bell |
| Oops! >>You've already got the brake mods (Mike Satur) and upgrades to performance tyres.<< I got that wrong didn't I? Brake mods are highly recommended as are handling mods. There have been a number of threads on these subjects. The SP Cheetah that Phil Raby drove for MG World didn't have these mods, and was frankly scarey. My revised (personal) option list for a VVC upgrade would be: 1. Techspeed suspension (lowered, mildly stiffened) with poly bushes. 2. Upgraded brakes (awaiting the excellent value set up from HJW motorsport) 3. Full-on monster bolt-on performance gadget for the decade- the TT supercharger. :o) Subject to Technical reassurances and waranty ofcourse ;o) Rob |
| Rob Bell |
| >>The newer version uses the standard MEMS Rob, I recall a conversation with whatisname at Stephen Palmer last summer which led me to believe that it was the first Cheetah that had a standard MEMS and the (almost stillborn) Cheetah 2 had a non standard MEMS. In fact some of the early problems with the Cheetah were (rightly or wrongly) blamed by SP on the standard ECU. Have Turbo Technics gone back to a standard MEMS for their kit? Paul P9 VLS |
| Paul |
| Nuts- I can't find the road report for the Cheetah2 now to check... I'll report back when I have confirmed or refuted what I said. Odd- I am sure I was right, as the conversion was being marketed as a cheaper, knock-down kit. Given that the full-house Cheetah convsersion wasn't to everyone's taste, that was a good thing IMO. Rob |
| Rob Bell |
| Hi all, Having been occupied all week I find this threads development quite interesting. In terms of achieving greater power (BHP) there are a number of ways to reach approximately the same point. These different routes involve different costs and different depths of interference inside the engine. One aspect that isn't really adressed yet is how does each mod affect the normally used rev band. If this is a road car then it would be say 2000 to 6000rpm whilst the VVC will be about 1000rpm higher for both. To have a substantial increase in peal power is only half the story. If the same linear increases seen at peak are reproduced throughout the normally used rev band then the car will be significantly faster. If however there is a loss at lower rpm, evening out at a mid way point and then showing gains, the car may actually feel faster due to the manner of power delivery, but actually be no faster when checked back to back. Alteration of the gearing is a very real 'leveller' as the actual overall gear ratio if lowered increases the torque multiplication effect. So if you have 100ft lbs and the gearing starts at 5 to 1 then you have 500ft lbs working for you. If the gearing is lowered the numerical ration increases so if the gearing is 6 to 1 then you have 600ft lbs with no engine changes. Changing the final drive ratio doesn't always work in practice due to the actual design and assembly of the gearbox. It can be done, but there is a little more than just a couple of bits to change and then because of gear tooth mesh and wear factors the last thing you want is a whining gear. Currently I am actually looking at some production alternatives in standard gearboxes and would initially have to mention the 200 BRM as this is an interesting gear cluster and final drive. (Different to the Vi. I don't have the latest 25 GTi data, so can't comment if there has been any further changes.) Standard production boxes have the advantage of being cheaper (usually) and wider availability. I have at the moment a couple of engine projects with 1.8 litre non VVC K series with some differing routes for each. Both have more emphasis on filling out the torque curve rather than concentrating on achieving every last bhp, although there should still be a reasonable increase at peak. Moving on now to the latest issue of CCC mag. (March) The six page spread on very specific 1.8i K series tuning done at QED makes for very interesting reading. Of specific note is the achieved power of the second hand engine with a pair of cams which for this feature is a start point. It is perhaps unfortunate that they were not able to measure the actual power of the engine with the original cams to really show the benefit of the modified ones, however I have seen enough standard engines to concur with the comment that the standard 1.8i spec is often a little stronger than the 118bhp paper figure. Accepting this as a reasonable start line the extra 20 bhp achieved on this engine does mirror the comments made by Nick with respect to his cars gains. It would then seem reasonable to expect other cars to benefit to similar levels with the same treatment. The next significant fact from this testing is the clear indication that the VVC alloy manifold was not just a waste of time with this engine, but a complete disaster. I certainly wouldn't regard being able to achieve the same peak power 500 rpm higher in the rev range, and serious losses below that as anything other than a disaster. The tests went on to show some very disturbing results for the throttle body tests. Gains at the very top end of the rev range in the order of 10bhp (Just short of 7%) but a loss of 14 bhp at 3000 rpm (20%) is terrible!!! This was the worst result for the throttle bodies but the other tests didn't didn't really achieve anything other than create an engine suitable for track use. These tests only cover a small area of potential changes, but give some clear indications. The first is that cams do seem to work well. The second is that the plastic manifold's reputation of being restrictive on top end power above say 150bhp is probably misleading, by being an incomplete statement. It may well be restrictive above these power levels, but if the alternatives can lose far more than gain in the low and mid range then how many would chose to follow that route? This is an area I have specific interest in and one that I have been intending to follow up. I was going to do some back to back comparisons with the VVC inlet manifold, but add yet another consideration which comes in the form of yet another alternative MPi manifold as found on the 91 to 94 MPi Metro GTi's. This is a cast alloy item with an internal volume similar to the plastic manifold and with runners following an interesting and very smooth curvature from the plenum to the head face. It is intended to use this and compare it to the others. As the design is different it may give some interesting results, probably similar to the plastic one, but thats just a guess pending the test. However it wouldn't be the first occasion an old design was best and was sacrificed in the name of economy of production, so fingers crossed. Rog |
| Roger Parker |
| Sounds like some very interesting tests- and your own ideas sound fascinating. I for one will be very interested to hear the results. Most interested to hear that the cast alloy VVC inlet manifold isn't as good as was thought on these boards... completely dispelled that notion for me anyway. Rob |
| Rob Bell |
| Hi, What an epic, Rog. I had to log off to read that lot! and it makes interesting reading at that. Make sure and gives those camshafts a good home (chqrcdtq). With regards plastic and VVC alloy inlet manifolds, i must say that i did look at fitting a VVC unit to my MPi but after careful consideration, i did opt for leaving the standard one in place. For one thing, some tricky alterations were needed, and then again, after Pete Burgess's comments on turbulence and overall volume air flow, it seemed like a good idea to leave well alone. And it all works very well as it is. Steve, look's like good weather tomorrow, see you then, lets go for a blast. Nick |
| Nick |
| >>>The newer version uses the standard MEMS > >Rob, I recall a conversation with whatisname at >Stephen Palmer last summer which led me to believe >that it was the first Cheetah that had a standard >MEMS and the (almost stillborn) Cheetah 2 had a non >standard MEMS. Paul, I found the article in the Dec/Jan 2000 edition of MG World. Quoting Stephen Palmer from that article: "We insisted that the conversion did not affect the MGF's reliability and ease of servicing. To this end, we have not made anychanges to the existing MEMS software or the anti-theft device, so that the standard MGF faultfinding procedures can still be performed by any dealership." I also seem to recall that the original Cheetah had an ICON Superchip engine management system... I do not know what the CURRENT turbo technics specification is- perhaps a call to Moss, Brown and Gammons or even to Turbo Technics themselves would clarify the situation. Rob |
| Rob Bell |
| Nick Thanks for the spin in your car. It was a good morning out. Your got me bitten. I will be looking into CAMs etc this week after checking what the insurance is going to cost. |
| Steve |
| Thanks for putting me right Rob. Paul P9 VLS |
| Paul |
| Rog wrote: >>The next significant fact from this testing is the clear indication that the VVC alloy manifold was not just a waste of time with this engine, but a complete disaster.<< I wonder if it was just badly matched to the head? Maybe the VVC manifold doesn't match the stock (non-VVC) head properly. >> ...yet another alternative MPi manifold as found on the 91 to 94 MPi Metro GTi's. This is a cast alloy item with an internal volume similar...<< I believe that this is the one used on the Supersport conversion (128bhp, cams + remap + manifold/plenum) that Caterham used to supply for the 1.4K. It was a Rover development and upped the output to 128bhp. I had one, it was a belter! Mike |
| Mike Bees |
| Interesting comments Mike. I did have a chat with Dave at Autosports, where we touched on the K series. (Had more to talk about past things, from when I first met Dave in 1988.) I think that the results with the VVC manifold surprised them also. From the figures I doubt that a mismatch would provide that result, and if it were then I expect that it would have been quite obvious. I remember some previous testing I have done where a steel plate was created to the same pattern as the manifold gasket, except that instead of being round and following the curvature of the port, it had a flat bottom that menat that about 15% of the port was blocked off. This resembeled a 'D' with the flat being at the bottom. The idea was to 'trip up' the airflow and create additional turbulence. It worked as the mid range filled out and the top end remained the same. That was a significant mismatch which is why I feel that simple port mismatch will not have the effect reported. Your experiences with the earlier style are very encouraging, showing that my intentions are on the right course. I actually didn't know about the Caterham connection with this manifold so if it does work with the 1.8 capacity then this may be a time to go out and buy up all the old MPi manifolds before and make a killing when everyone else wants one!! Rog |
| Roger Parker |
| Hi Rog, Could it be that the mismatch isn't between the manifold and the head but between the throttle body and the manifold? I mean, the k-series 1.4 L has the same throttle body as the 1.8 VVC engine so one should think that the VVC-engine should need a larger bore throttle body. I have a Rover 200Vi and it feels like if the engine can't get enough air from about 5000rpm Recently I bought a second hand throttle body and enlarged the bore from the standard 48mm(?) to about 51 mm and made a fitting brass throttle for it. It definately feels a lot better in the high rev's. Although it was not such a great succes while the body yet hasn't enough stiffness anymore so it sticks sometimes. Arend |
| Arend Groen |
| Slightly off kilter, but *may* be of some interest for some... It appears that a couple of Lotus Elise 111S owners have gone for the Turbo Technics conversion (exactly the same as the Cheetah conversion for the MGF). They've been chatting about it on one of the Lotus BBS's: http://www.remarq.com/read/lotuscar/qAn8v7wgXAb0C-2k9?d=135#LR Nothing but smiles reported so far... Rob |
| Rob Bell |
| Hi, a nice thread. I like it. Recently some german chaps talk about silly chip-tuning as single add on etc. For the case that Dirk joins this thread...Dirk how where things have gone if you had known this before :( http://kfz.freepage.de/epromer/ I know he can read german too. So this chip-crictical webside (only german) may be of interest. Cheers dk |
| Dieter |
| Hi Guys wow what a thread! I know the answer sell the F and buy a Honda s2000 You gain loads of bhp but lose loads of cool/style/mates/ancientheritage It's up to you! rule no 1 if you want a bhp -impress the blokes down the pub then don't get an F sh*t they're jealous of warmed over Renault Clio's Lower it make it louder and enjoy!!!! Rob Bell what's your email address I have exciting news?? Neil |
| Neil |
| Rog wrote: >>... a flat bottom that menat that about 15% of the port was blocked off. This resembeled a 'D' with the flat being at the bottom. The idea was to 'trip up' the airflow and create additional turbulence.<< This can help the air to turn a sharper corner than it would otherwise want to. The standard K16 head does turn the port downwards a bit too sharply so this might help there. The VVC head is better in that the ports start a bit higher up and so get a straighter run to the valves. Of course this is another reason why slapping a VVC plenum onto a non-VVC head might not work too well, although as you say you'd expect to see a loss at the top end if the flow is being compromised. Mike |
| Mike Bees |
| Hi Neil, e-mail address is robert.bell@ucl.ac.uk So what is the news old chum? Rob |
| Rob Bell |
| Hi all! I own a MGF VVC and I love it!! But I want to do some changes; I want (like everybody else) tune up more HP.I also want to put in wood in the intrior ( make it look mor expensive) and I want to change my plastic (air & heat) controls to the new type I have seen in the new MGF. My questions to you proffesional MGF owner are 1. What shall I do to get mor HP ( max cost £4000)? 2. What and where shall I buy the things I need to make the car mor luxuary? 3. Where do I find a deskription how to make the bulb in the lighter start to work? Maby is the best option to go to the UK or Germany to a proffesional garage and let them do all the work. If so where do I find the "best" and in wich country is the prices lowest? Thanks all! |
| Kristian Karlsson |
This thread was discussed between 04/02/2000 and 21/02/2000
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