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MG MGF Technical - On a day like today.

Days where you can really thrash the "F" are getting more and more limited as winter draws in, but today was an exception.

I very rarely test the top end power of my F, but a nice dry sunny day like today seemed ideal.

After fitting my K&N, and Stainless Exhaust, I found the car has definately more aggressive, but it seems the power seems to plateau higher up.

I recently fitted the Trophy throttle body, and the power seems to have vanished completely under 3,000 revs, and the top end has been compromised even further.

Just drove down to Gretna (spit, was even forced to cross into england-shire) and car was handling nicely,
but seemed to only crawl up the rev range at high speed.

However, refueled and headed home. with a bit of encouragement from a Porsche 911, decided to push the car a little harder than normal.

And now as if by magic, the car seems to have all its power back.

So question is why?

Really pushed the car, pretty much hitting upper limit of the car, ok after 20 minutes or so, the temprature was soaring a bit, could this have changed character of the engine?

Could pushing it that bit harder, removed any blockages? fuel or otherwise?

This seems to be a common trend that the car behaves so much better for a couple of days after I've pushed it a wee bit.

I'd like to keep the car behaving how it is now, preferably without compromising my driving licence though.

Any ideas? Does it seem the car is struggling to provide enough fuel?


I think the cooling system is amazing in the F, within a few minutes of returning to a sensible speed, the temprature had dropped back down to normal.

paul weatherill

MEMS engine management can take a while to adapt, it was exactly the same when i put in my ITG and TTB, drive for a while, no change, then it just gets better and better

Hi Paul,
fit an adjustable fuel pressure regulator and the torque will be present at all times ! This addition seems useful when "everything" including Trophy throttle body ( or even larger ! :) is fitted.
And of course there should be a minimum length of hose from whatever filter to the throttle-body to get any decent take-off at lower rev´s....

BR, Carl.
Carl Blom

And for some funny reason it is not the length of the journey but the number of engine on/off´s after an improvement as TB or exthaust is fitted that seems to re-map or adapt the MEMS.

BR, Carl.
Carl Blom

Alot of it has to do with the very cold air that is going into the engine via the filter. I previously had a very modified car and was in a club,we took part in a lot of shows and speed trials at the likes of santa pod and York Dragway and found the colder and 'fresher' the morning, the quicker the cars would perform. All to do with getting cold air into the hot engine.

Thanks for comments guys.

GC i hear where you are coming from, totally agree.
However temp/climate where the same going there as coming back yet such a big dfference.

Just had a sedate drive home, and car still seems good.

I now have that F-induced grin, that I had when i first bought the car, and then again when i put on the K&N.

<<fit an adjustable fuel pressure regulator>>
this is what i am thinking, i may need. hmmmm.

If its the MEMS that has learnt these new settings just hope it doesn't forget again too soon.

Ok so what can ppl advise about fuel pressure regulators ;-)

paul weatherill

The F really seems to respond to a good flogging, but I have no idea why. Just today I felt that mine was being a little sluggish, so I took it for a half-hour high-rev blast and it seems much better now.

Or maybe it's juts that I feel much better now....
David Bainbridge

Adjustable fuel pressure regulator

is this like Power Boost Valve?
Hanah Kim

Also don't forget that the VVC mechanism doesn't kick in until the oil temp has reached (I think) 70degC. And if the connection is a bit corroded....

This thread was discussed between 31/10/2002 and 01/11/2002

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