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MG MGF Technical - Slow VVC

Can't help feeling that my F is slower than it should be. The books qoute a 0-60 time of about 7.6 seconds but my mates unmodified Saxo VTR (booked at around 10 seconds 0-60) is very, very close to keeping up. I've had faster cars than the F in the past so when test driving it I nevers really expected it to have flames comming off the rear tyres but now I'm starting to worry that theres something mechanically wrong. Seems to drive and run fine though. Theres no change in pitch or tone throughout the rev range like on a Honda engine when the VVC kicks in. Could this part not be working and if so how do I check. When choosing the F I never bothered to look at anything other than a VVC and I bought the first car I found and so havn't driven another to compare so any advice would be appreciated!
Dominic

Hi Dominic

How many miles have you done.? Because It takes over 12,000 miles before the engine becomes loose. You also need to keep the revs up over 5,500 rpm, especialy in 3rd and 4th gear.
Richard
Richard

The cars a 96 on a P with 33500 miles on it so its well run in but even above 5500 rpm I don't feel any increase in power or change in engine noise, should I?
Dominic

Dominic, you should get an increase in noise and speed over 5,500 revs. Check the air filter and make sure their are no kinks in the rubber tube between the air filter and throttle body. Otherwise get it checked out on a rolling road.

Shouldn't be a major problem.

Richard
Richard

Thanks Richard I think I will pay the money and get it rolling roaded, should get a bhp figure at the wheels as well which would be interesting. Not very familiar with the K series engine but are they tunable? Very familiar with Vauxhall engines and you can't really adjust them other than the idle speed. Everything else is done by reconfiguring the engines ECU. Is the K series the same and if so is it worth spending the cash? Has anyone else had a rolling road tune and what was the result?
Dominic

Dom
Dont quite know what you was expecting as it is only an F the difference on the road of 2 seconds is probably not that great but the little saxos do seem to have quite a bit of poke the VTR has a 0-60 of 9.3, are you sure its not a VTS.
Ian cresswell

Yeah deffinatley a VTR owned by a good mate and very standard indeed. Might not have made myself clear as to the speed. He was infront of me when we pulled away and I diddn't fluff the start but at first he was pulling away. I was reving up to 6500+ through the gears and it wasn't until we got up to the 60 mph mark that the F began to reel him in. He's no where near me for top speed which suggests that theres nothing drastically wrong but still!
dom

Don't forget the rear-wheel drive/mid-engine factor - the level of traction means that you can rev to about 5K and then drop the clutch and the wheels barely slip on a decent surface. Should put you several yards ahead of the Saxo before going to second.

Also, I find the first/second change really slow with the standard box, which doesn't help.

E
Ed Clarke

Ok I'l try that on the starts. To be honnest I have been pamering the car in general, kind of scared that if I rev it too hard one of the cars many troublesome components will brake but I've finally got round to getting a fairly comprehensive warranty with warranty wise so I guess its time to give the engine some stick. All than remains to be seen is if something breaks, will they pay up. Has anyone had a claim with them?
Dom


Another thing to remember is that engines get quite choked up after years (weeks!) of short journeys.
A good long motorway journey always helps. Or to use the phrase my mechanic used "kick the sh*t out of the engine for a while and it'll be faster".

I'm not known for being kind to cars/engines so I normally thrash the engine. But after a recent prolonged blast round a track the car felp significantly faster.

Oh... and on the VVC watch for the oil temperature sensor going. If the oil isn't hot enough the VVC mechanism will not fully kick in. So if the (cheap) sensor fails - as it did on mine - the car drives like a 1.8i with the VVC mechanism just coming along for the ride.

Next time it's serviced complain about performance and get them to do a full testbook check.

Hope this helps,
P.
Paul Nothard

OK, move out the way lads its Paul (Thrash the living daylights out of the engine) here.

I've had my 2000 VVC from new for 10 months now and I've done 18,000 miles on it including a drive from Geneva to London and back.

In first gear I've revved it up to the 'limiter' 7000 plus rpm (although I don't do it too often, I am not that mad) and I can objectively say there aren't many cars on the road which have been able to keep up with me in first gear alone.

I raced an Audi S3 (does 0-60 in 6.5s)once and I left it standing at the lights, its wasn't until we swapped into 2nd gear that his turbo kicked in with its 225 BHP that he started to overtake and pull away from me.

But otherwise I can leave most bigger engined BMW's for dust at the lights. Hot hatches in general are easy prey, I can outsprint them from the start and still have plenty of power to pull away from them on the motorway.

I don't know the 0-100mph time on a VVC with K&N but that is truly fast. Only a RS4 has ever overtaken me when I do this on a well travelled bit of motorway.

On the motorway the VVC is even more impressive accelerating whilst at speed, but you do have to keep the revvs up from about 5000rpm.

My VVC used to make a sort of noise from about 4000rpm before I had a K&N fitted and now I get a sort of whistling from about 4000rpm and all the power and acceleartion in the car comes from about 4000rpm onwards.

The traction and balance on a MGF gives it a great advantage over other cars especially front wheel drive cars when accelerating from standing. You pull away clean as they are standing still spinning the wheels.

But maybe you should get a K&N and yes use all the revvs.




Paul

Reading this and since I have been driving my 1.8i I wish I had got a VVC, oh well I still love the car, however I have to say it's quite slow.

Why is it you can floor it and it will hardly wheel spin?

I checked the 0-60 time myself, stop watch, so not that accurate and got 9.1 seconds.

A mate of mine in his Golf can out accelerate me, they should be about 8.5 secs.

Maybe it's me!
Ashley


Sit at 5000rpm and drop the clutch. :-)
Kills the car, but if it's 0-60 times you're after you have to abuse the car.

From a standing start in the dry it's hard to spin the wheels of the 'F as i) it doesn't have enough power, ii) the engine and weight is nearer the back, and iii) the same as all rear wheel drive cars - the get better traction as the car's weight is thrown to the rear under acceleration.

The VVC is good and I love it, but the 1.8i is not as far off as people think. In some ways it's a better car as you can modify more on it. It also doesn't require the franetic (sp?) driving style that a VVC needs to get the best from it.
All down to driver preference at the end of the day. :-)

Can't wait for some of the rumoured faster, more torquey engines to come out.

P.
Paul Nothard

Good points already made, but worth emphasising:

1. City driving is BAD news for engine performance- they soot up as Paul says. The improvement in the feel of the car is remarkable after a throughly good thrash (through the gears, changing close to the red line)- although do make sure that the oil is up to at least 60 Celcius before trying this!!!

2. Failing ECU coolant temperature probe. Your car is now old enough for this to start being a problem- they seem to start failing at 4-5 years of age. They are cheap (10 quid) and easy to replace (see the HGF link on http://www.mgf.4mg.com) - worth doing anyway.

3. The VVC mechanism is not as harsh as Honda's crude VTEC mechanism, but none-the-less, the alteration of timing duration should be palpable...

4. There are some good VVC engines and some slightly less good VVC engines. You maybe unlucky in having a 'Friday afternoon' motor- but don't assume this until you get the car checked out. Also check the condition of the ignition leads and spark plugs. The latter should last 60k but many advocate earlier replacement. In any case, check that the spark plug gap is set correctly...

Check the basics before investing in a RR.

Rob
Rob Bell

I have heard that you don't get much acceleration after 5,000rpm but I have found that from 4,500 - 6,500 is where it pulls the most, I have a 57i kit so this could be the reason.

First gear is very slow up until 4,000rpm, then it really takes off

:0)
Ashley

Thanks all for the help and I will try a temp sensor for the coolant. When all said and done I'm not really dissapointed with the power because thats not really why I bought the car. I wanted a two seater convertable and thats what I have. I've owned many a faster car than the F before it and despite what some delusional owners think I know that its never going to out run an S3 or an M3 or a nitros oxide guzzling dragster or even a well sorted hot hatch for that matter. Put it this way, if I were to overtake a one litre mini I would only need to use half throttle. The mini driver thrashing his engine to peices may think that he's not that far off but in reality......Just thought they might be something wrong but going back to the mileage, short run, sooting up, HT lead, spark plug thing I did hear something interesting aout the plugs - see new thread 'plugs'!
Dom

One of the other limiting factors, for me, is how fast I can change from first into second (third and above are much quicker changes).

Probably better technique (and possibly a better gearshift from Mr S) would help if I were really worried about such things. However, I'm waiting until it fails before I replace (if it ain't completely broke, don't fix it!)

I concur with the "new plugs" idea: my VVC felt much more "urgent" after the change at 44k miles.

Neil.
Neil

dirty plugs & filters can be the only reasons

I'd like to retry a VVC right now, because I got pretty used to my M3 mindblowing acceleration times... I guess I'll be the only one entitled to say a VVC feels slow ;)

I wonder if Rover shouldn't introduce an M alike SPORT button which basically switches the ECU to a more thirsty but more performant program plus a much more sensitive fly-by-wire accelerator pedal setting.
Dirk

>>>The VVC is good and I love it, but the 1.8i is not as far off as people think.

Yes, I've been experimenting with the ol' VVC at high revs recently and I was impressed by the way it gets ever more powerful the faster the engine goes. Incredible! However, it's a pretty marginal effect in daily use, I reckon.

I got a VVC largely because of the things that come as standard - mainly the ABS. The ABS has already saved my car *twice* in three months in two incidents that really weren't my fault (oh yes, says everyone). No really, they weren't. The friendly little gremlin hammering the bottom of my right foot as I glided to an amazingly rapid halt was incredibly reassuring. This is, I think, reason enough to get a VVC instead of a Trophy, although it seems there is debate about whether you can get an ABS Trophy.

Oh, and surely a car is easier to sell with ABS? Not that I ever want to...

Other reasons to get a VVC - trvia like those yummy alloys, the CD and leather. Yes I know you can add them to an MPi, but you soon get up to the cost of a VVC anyway! Also, the K&N makes a bigger difference to the VVC, I think.

Does driving around with a bhp/torque vs. rpm graph on my passenger seat make me a saddo?
David Bainbridge

>>Does driving around with a bhp/torque vs. rpm graph on my passenger seat make me a saddo?

Erm, yes; but it also means your memory is going.

:-)

E
Ed Clarke

ABS is a must (it should be standard on all cars). The ABS on my VVC probably gets more use than it should but it has definetly saved me a couple of knocks.

While were talking about the VVC I noticed that I nearly hit 0-100mph in 2nd gear today on my way to work (wasn't really pushing as hard as I could either).

I think I've probably got a very good example of a VVC engine.
Paul

Paul 0-100 in 2nd that's good, my mpi will only do 70mph in 2nd before it red lines, then 100 in 3rd, top end is very slow!
Ashley

Ashley, I reckon you still need to put more miles on your car before you get the best out of it.

My VVC when new was quite sluggish and even after the running in period didn't feel the revv happy way it feels now after having done 18,000 miles in it (in 10 months! although I think you're going to beat that record!)
Paul

This thread was discussed between 07/07/2001 and 12/07/2001

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