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MG Midget and Sprite Technical Just for fun.....@ Aldon Rolling road BBS discussion at MG-Cars.net
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MG Midget and Sprite Technical - Just for fun.....@ Aldon Rolling road
| I am booked in to Aldon for a rolling road session on Friday, so lets all have a bit of fun and see who can post the best guess at what bhp at the wheels I can max out at.(approx 6500rpm) The closest guess gets a bag of sweets at midget 50! The car is going in to see if they can retard their own dizzy when boost kicks in as I dont have a megajolt fitted at the moment Spech as follows 1310cc low compression (8.2.1)A series. Steel lightened flywheel. 270 cam. big valve gas flowed head, inlet 36mm, exhaust 30mm. Standard Metro turbo with adjustable Avonbar actuater. Forced cold air intake but no intercooler. At the session I will probaly run at about 10 psi boost. Thats enough information for now otherwise someone might get it spot on!! And just for the record, its not been on the rolling road before with all these mods fitted so I havent got a clue what results I will get. Good luck... |
| Rob Newt |
| If you do only use 10 psi boost (and boost makes such a great difference so no point in guessing without knowing the boost) the the HP at 6500RPM I think will be in the region of 120/125. @ flywheel. |
| Robert (Bob) Midget Turbo |
| 130 is my guess Rob. |
| steve cowling |
| I'd say 120 at the wheels. |
| Onno Könemann |
| 107 Peter |
| P Burgess |
| 97 at the wheels |
| PeterJMoore |
| Bob just to clarify and make it a bit more clear, I will get them to set the car as best they can at 10 psi, once I am happy with the car I will ask them to give me a run at 15 psi, I adjust my boost using a solenoid switch so there is no in between, just 10 or 15 psi. You do realise this is serious stuff you know, we are talking about a real bag of sweets to munch on the way back from M 50, so sorry to say I cant except a guess of in the region of, must be one figure only ! Pete 97 at the wheels ! I am upset already.(but you might be right) |
| Rob Newt |
| High boost tweaked Metro Turbo losing 25 through transmission, giving 130ish at flywheel. Peter  |
| P Burgess |
| LOL OK Rob point taken guess I will give you the benefit and go with the 125 @ Flywheel Ten a boost of 15psi is getting serious and I will go with 150 @ Flywheel. |
| Robert (Bob) Midget Turbo |
| The 270 cam will be past peak BHP long before 6500. I'll say 110 at the wheels @ 10 psi and 116 at 15 psi because you don't have an intercooler. I'd also be interested in how big the oil cooler is, what the cooling system is like (pump, pulley and rad) and the ambient air temperature on the day. If you can get a chum to take water and oil temp readings that would be interesting or better still video it. My limited experience with turbo A-series is that you need a montego size intercooler and a really efficient radiator (not standard spridget) to get big bhp. Don't forget to get a readout of the torque as well as the BHP because that's where the turbo will really wipe the floor compared to a normally aspirated A or K Series. |
| Daniel Thirteen-Twelve |
| Hi Rob, I'll go with 118bhp at the wheels. Good luck!! Mark |
| Mark Whitmore |
Rob if the winner is from out of town will you also reimburse them for their travel costs so they can pick up their prize in person? :) |
| Greg H |
| Hi Daniel Agree that AT will wipe the floor with ASeries at 10psi. But the 1.8K is a tougher challenge... allow me to summarise: - 1310 Aseries, 10psi, no intercooler - at best (I mean without losses) engine behaves as approx 2.2 litres - but we still have 2 inlet ports and Aseries valves (one inlet/outlet per cylinder) - no intercooler will restrict boost and/or cause ignition to be retarded (needs ECU really, for boost retard) I have numbers from Aldon for my 1.8K from visit with MGCC last November... so am ready for the comparison. A |
| Anthony Cutler |
| Ooh, let battle commence. Ha Ha |
| Neil K |
| I reckon on 95 at the wheels but being in a generous mood I'll up it to 102 just for the sake of being over the ton Willy |
| William Revit |
| LOL William - many of these people haven't even got THEIR tickets, so, I doubt he'll pay for you to come ;) I'm going 98 at the wheels |
| rachmacb |
| 104 BHP at the wheels. Jelly beans please! Dave |
| D Brown |
| Hi Anthony Graph of VVC on Jenveys with Emerald. Was 183 at wheels with 18.2 losses giving 201 at engine. As you say, quite a tough target for a Turbot A series. Peter  |
| P Burgess |
| I know a good K series will kick out 200bhp but not as road usably as a turbo A.... |
| Daniel Thirteen-Twelve |
| Hi Daniel The above VVC is amazingly docile, built by frontline it is really tame, just delivers the goodies from just under 2500 rpm. Turbots always seem a little peaky to me compared to when they be off boost. Peter |
| P Burgess |
| 127 bhp at the wheels :-) |
| S Langston |
| Dont forget to bring spare clean underpants... and a headgasket. ;) |
| Arie de Best |
| Hi Rob, if you need any moral support I am available tomorrow, just let me know the time!!! I can come armed with a video camera if you wanted some footage of the event. Also I can save you postage on the bag of sweets!!!!! Mark |
| Mark Whitmore |
| Ok here we have the final list for this once in a life time prize...... Peter J Moore 97 @ wheels Rachmachb 98 @ wheels (Bob)MidgetTurbo 125 @ fly wheel less 25=100 @ wheels William Revit 102 @ wheels D Brown(jelly beans) 104 @ wheels P Burges 107 @ wheels Daniel Thirteen 110 @ wheels Mark Whitmore(camera man) 118 @ wheels Onno 120 @ wheels S langston 127 @ wheels Steve Cowling 130 @ wheels Good luck to all..  |
| Rob Newt |
| Oh nothing but the best there ;) Looking forward to my Jelly Beans :D |
| PeterJMoore |
| Hi Rob, interesting reading on this thread, my 1098 put out 56 at the flywheel and my 1.4 k-series put out 119 at the flywheel, so I'd hazard a guess at 99 at the wheels for your car, Hope that you have a good run, & post your graph for us to see! John |
| John Collins |
| Rob, I'm sure you will post the Aldon printout on this thread. We are all waiting with baited breath to see the results. Good luck. Oh yeah, take your ear plugs with you!!! This was my K at Aldon last November.  |
| Neil K |
| Hi All We had a Metro Turbot in today, didnt want to mention it until we had done the testing incase things went bang! The engine is more or less standard (inc turbo cam), one of our large inlet valve turbo spec heads. The first line is with 5 psi the second line is 10psi. The transmission losses were 20.2 so engine powers were 137 and 152 respectively. The maths tells us that the bhp increase from 5 to 10 psi = square root(25/20)x bhp at 5 psi, which is 11.8% which is 130.5 at wheels, not bad getting 132! Peter  |
| P Burgess |
| THE turbo midget then? Well done Steve - and Rob, of course - NOW I expect to see both of your names on the ticket sales list for Midget50 ;)!!!!!!!! Look forward to seeing pictures of the engine and the session :) |
| rachmacb |
| Nice one Peter. Rob -25%? where did that come from? :) I am sure Aldon will give you an accurate flywheel figure for comparrison. However from Peter's test I am well out, no wonder my clutch gave up the ghost! |
| Bob Turbo Midget England |
| Ok Folks, all done. AND THE WINNER IS S. LANGSTON(DARK HORSE) 127 @ wheels With Onno a close second Graph showing 149Bhp @ flywhhel = 124 Bhp @ wheels. 6175rpm boost set at 10psi Bob, I guessed at loosing 25 Bhp to the wheels from the flywheel and it turned out to spot on.  |
| Rob Newt |
| This is where it get intereting when I ran at 15psi of boost. 173 Bhp @ flywheel and 148 Bhp @ wheels !  |
| Rob Newt |
| Damn just missed the big prize |
| Onno Könemann |
Just to show it was my car.
 |
| Rob Newt |
| Hi Daniel So we have: AT with 10psi: 149 bhp and ~140 lb-ft AT with 15psi: 173 bhp and ~166 ib-ft (?) 1.8K n/a : 154 bhp and 170 lb-ft (Both cars on Aldon dyno; the 1.8K has small butterfly mod and self-developed map for Emerald) Seems like the K wins on torque. But good effort from the Aseries! This is a better way to go than 1380, 280 deg cam, weber, high-lift rockers, and lots of revs (IMO); 1/2 bar boost makes a very reliable road-engine. [When Tamsin drove a 1.8K for the first time she wasn't impressed by the performance, but she was running 1-bar plus on her ASeries! However, must be said the AT liked to pick up on #4...] A |
| Anthony Cutler |
| Hi all, hopefully the link below will work (fingers crossed). This is the 10psi boost run. http://www.youtube.com/watch?v=C2Et2B7ZtGU Thanks Mark |
| Mark Whitmore |
| The link below is for the 15psi boost run. http://www.youtube.com/watch?v=OrfwZlMM2_o Thanks Mark |
| Mark Whitmore |
| Nice one Rob I wonder what my 20 psi engine is developing? That has certainly persuaded me to stick with it and sort out the oil leaks :) Thanks |
| Bob Turbo Midget England |
| I'm blaming PB for throwing me off the scent. I suppose a VVC K-series is flexible because that's exactly what the VVC does? 92mph at peak power so I'm guessing that's 5500rpm in 4th gear. I'd still be interested in how big the oil cooler is, what the cooling system is like (pump, pulley and rad) and the ambient air temperature on the day. If you can get a chum to take water and oil temp readings that would be interesting or better still video it. |
| Daniel Thirteen-Twelve |
| Rob, Very impressed. Great to see the video by Mark too. Look forward to seeing it at Midget 50. Neil |
| Neil K |
| Holy sh#t thats impressive!! Turbo K is the next step for me then! Steve |
| Steve H K-ser |
| Fancy blaming me Daniel :) Our Dynocom logs the pressure humidity and temp and converts to an SAE figure, can press buttons and see what it is on day and SAE looks good, DIN always a little further away from 'on the day' figure. Cos it logs it all down we can run cars over a period of time and get same base readings or accurate differences in tuning. Also good dragging graphs across so see differences with different specs, will be good as the database expands. Bob...bring it down and get a reading before it runs out of oil or blows a gasket:) Peter |
| P Burgess |
| Might just take you up on that Peter been a long ime since I was in your workshop. Going to get my fuel tank made and install a couple more breathers and then we will see Thank you. |
| Robert (Bob) Midget Turbo |
| Well done Rob,those are good numbers.When are yougoing to run the strip! |
| steve cowling |
| Rob Fantastic result for you - should be a great drive I don't mind missing out on the jelly beans for the sake of good horsepower - enjoy it Cheers Willy |
| William Revit |
| What do i win then ?! Two weeks in Benidorm ? Doing well the Baggies beat Liverpool 2.1 today as well. Things are looking up ! |
| S Langston |
| But more important than pure power Has it improved and does it drive nicer? |
| Onno Könemann |
| S. Langston you will need to be going to Midget 50 to collect your prize as too expensive to post ! Are you going? we are are hoping to organise a road run from the midlands, meeting at Corley services on the Sunday morning. Now Ive just noticed your a Baggie !!! deals off... Keep the gold flag flying high. Lol. Onno It behaves very well on the road, thats the beauty off the turbo, at low revs you would not tell its modified, then at 2500-3000 rpm all hell is let loose, with all my usual brake and suspension mods I just love driving the thing at the moment, then i get back and see the oil on the floor ! but thats another story Steve I think myself and the car need to shed some weight before I start running up the strip...its a thought though. |
| Rob Newt |
| Rob are you telling me that the oil leak problem has not been cured by extra breathing? |
| Robert (Bob) Midget Turbo |
| Bob I have reduced it a large amount(it was bad) as I have said before if I drive it gently then I only get a spot, the problem is I never drive it gentley ! I have spoke to Peter May about this in great length, he seems to think that the engine is now breathing sufficiently, so as the leak is only coming from the rear of the crank he said he is going to come up with something. Btw he blames the extra pressure the turbo produces. What baffles me is if you go on to any Mini turbo forum they never have a problem with oil leaks, this could be the way to resolve our problem. I will keep you posted. |
| Rob Newt |
| Hi Rob I believe a really good rear seal kit is well under development and hopefully soon to be available so keep your eyes peeled. We have never been very keen on the conversion sitting on the tiny crank flange. Peter |
| P Burgess |
| Peter, i'd be interested in your kit, have you any more details? cheers Brad |
| Brad 1380 |
| Hi Peter Thanks for giving me a bit of hope! Is it yourself that is developing the kit and if so how long before its in production? If you need a car to test it on just say the word and I will be up the A38 before you can bat an eyelid. |
| Rob Newt |
| Hi Rob Not me, had a phone call from a friend who is a MINI man through and through, he was asking me strengths of 1275 Midget engines...."all bullet proof I tells him". I said only problem p**s poor scroll on rear of crank....said was in final stages of bringing a 'proper' seal kit out.....goodie says I. We have had problems trying to source new seals for the Morris Minor Centre kit so I had three made in the end, as I needed one for an engine 'freshen up' Peter |
| P Burgess |
| Hi Peter Don't know if this is of any help to you but a good mate here runs a 5 litre Mustang racer which used to suffer badly from oil leaks when driven hard. mostly because there wasn't any vac. at full throttle to help the breathers work - normal puttering about it stayed bone dry. He found a kit somewhere on the net that feeds the breather down into a pipe fitted into the collector on the end of the extractors. It works like a venturi the faster the exhaust flow the more it sucks No oil leaks at all now - it really works well I've recently heard of an electric sucker for the breather as well but havn't eyeballed one of those yet Cheers Willy |
| William Revit |
| William, tried that, it doesn't work well for a road car as i found at certain rpm the one way valve can flutter due to exhaust pulsing & pressurise up the sump, at idle & high revs the evacusump worked well though. |
| Brad 1380 |
This thread was discussed between 30/03/2011 and 04/04/2011
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