Power loss under heavy acceleration

[GazChurchend]

Hi
I have had an Evo5 for just two weeks which is pushing around 360 BHP.
It was fine for the first week, but now if accelerating hard such as overtaking the car judders and the power just isn't there. If you ease off the throttle it isn't so bad. I know the car has always been very well maintained and looked after. It hasn't long been serviced.
Driving normally it seems fine and just seems related to a heavy right foot. Compared to last week when you needed a change of underwear when booting it even in 5 gear!

Its going to be a while before I can get it to someone who knows what they are doing so just thought I would get some ideas.

Any pointers would be most welcome.

Thanks in advance.

 

[Nick]

Id start on the easy stuff like plugs. Check they are all ok and gapped properly (.55 -.7mm).

 

[GazChurchend]

Will do.
Took it for a spin earlier and definately not happy under heavy throttling. Hoping its not going to be painful on the wallet at the moment!!

Cheers
Gaz

 

[Tom C]

Id start on the easy stuff like plugs. Check they are all ok and gapped properly (.55 -.7mm).

Hi Nick,
is it true you don't have to 'gap' Irudium' plugs?

cheers fella

 

[GazChurchend]

Somewhat better...

Hi
I had some new ngk plugs fitted at a place called Xtreme UK who reconed that had got rid of the missfire. It does seem to have improved but still does miss a little under load. I am thinking of trying some new plug leads but can't seem to find anyone who stocks them. Any ideas who might have some??

Originally they thought it was the wastegate actuator but their boost guage showed that it was fine and just a missfire.

Where is the best place for Evo parts???

Cheers
Gaz

 

[Nick]

Hi Nick,
is it true you don't have to 'gap' Irudium' plugs?

cheers fella

Not strictly true but effectivly true yes.
They have very hard to gap and will practically never change so they wont need doing.

 

[Nick]

Hi
I had some new ngk plugs fitted at a place called Xtreme UK who reconed that had got rid of the missfire. It does seem to have improved but still does miss a little under load. I am thinking of trying some new plug leads but can't seem to find anyone who stocks them. Any ideas who might have some??

Originally they thought it was the wastegate actuator but their boost guage showed that it was fine and just a missfire.

Where is the best place for Evo parts???

Cheers
Gaz

For bits like these we have used Alan at AS Performance - Rally Motorsport Specialists

 

[russell]

sounds like over boosting to me

 

[GazChurchend]

Much better now!

Hi all.
Since then I replaced the coil packs and that did seem to fix the problem but as I had got some magnacor performance leads I fitted those aswell and all seems well.
But on the subject of boost what is a normal max boost pressure to expect that is safe?
Does this change if the ECU has been remapped, performance exhaust etc.?

I have a Blitz boost controller with the Gain set to 5 and the Ratio set 42 and 48

I think I set the limiter to around 1.43

The Gain/Ratio was set on a rolling road by the previous owner and I havn't tried changing this as I figured they know more about getting the best out of it than I do!!