Foul me!

[davelittlewood]

The performance of the Chimp has been slowly getting worse over the past years/months.

Two weeks ago I took it down to Bentley for Carl Baker to sort out the alarm system.
230 mile round trip. By the end of it the car felt better but not great.

Over the past two weeks the car has got steadily worse.

I remember about 6 months ago I pulled one of the plugs and was surprised by how fouled up it was. I cleaned it and stuffed it back in.

This evening I pulled all 8 out and found this.



Close up of Number 1.



The plugs are all really fouled up.

SO.....

I stuffed in a set of BPR6ES and took if for a traz down the M1. I almost soiled myself!!

I've had the car for 5 years now and it has never run like this. Never. Toe down in 2nd and her arse is squirming about.

I know that a clean set of 7s would have improved the ignition no end but it has never run like this since I owned it, even after Dom rebuilt the engine 4 years ago.

SO.....

The question is, why are my 7s getting so oily in the first place?

I'm guessing (and hoping) that it's over fueling (and not piston rings, valve seals etc).

As all 8 are bad my guess is the MAF (rather than just one of the lambda sensors).

Answers on a post card please.....

I'll use it for the next few weeks (mixture of medium runs and commute to work) and then pull them out and have a look.

P.S.
Forgot to mention that idle is now super smooth and there's zero hesitation. 30 mph in 5th!

Edited by davelittlewood on Wednesday 21st October 22:59

[ClassiChimi]

I get the feeling it's over fuelling, not running quite right, at lower revs, that over time,,,,?
Hey that's good to hear she's better on the new plugs,,
Your not getting any smoke out the back are you?

[macdeb]

These cars only need 6's and they will clean up idle.

[davelittlewood]

Drive home tonight.
Seemed a bit hesitant at first but once warmed up.

Lit up the rears in second just by planting right foot down on a good dry road.

At this rate it'll cost me more in rubber!!

[Hoofa]

macdeb said:

These cars only need 6's and they will clean up idle.

Eh ?... I am running 8s not had a problem since I swapped from 9 to 8s

[Richard 858]

Nigel, surely the supercharger has a lot to do with that. I've found mine runs equally well on 7's or 8's although that was when still on Lucas 14CUX. Been recommended to stick with 7's with the MBE.

[Pupp]

I use BR8ECS plugs with no particular issues (bit of cold fouling if I have to restart a couple of times before getting up to temperature). Would prefer to run a 7, which I think would be spot on but sadly not available as a resistive plug in the ECS range.

Guess I could try an iridium equivalent but am just fearful a good blast of boost will simply blow those piddly little electrodes out the exhausts

[FlipFlopGriff]

My 7 plugs were black like that too, even after a few hundred miles. Put BPR6ES's in and they are now a nice brown colour after about 500 miles. Recently junked the extenders which has made it a bit better again.
FFG

[macdeb]

Hoofa said:

macdeb said:

These cars only need 6's and they will clean up idle.

Eh ?... I am running 8s not had a problem since I swapped from 9 to 8s

You are SC'd. CR isn't what people think it is, they are lower. 400/450's will only need 6's not 7's or 8's being nearer 8.9:1 and not the fabled 9.35:1. Even at that it wouldn't need 7's or 8's. 500's maybe 'if' they are nearer 10:1
I'm running 6's with the turbo and it's been much better, probably as most of the time it's negative boost [light throttle] but when pressing on a bit no problems.
PS; you going to NEC? maybe see you

Edited by macdeb on Friday 23 October 18:18

[caduceus]

FlipFlopGriff said:

My 7 plugs were black like that too, even after a few hundred miles. Put BPR6ES's in and they are now a nice brown colour after about 500 miles. Recently junked the extenders which has made it a bit better again.
FFG

Interesting....

[davelittlewood]

I'll be at the NEC, looking for bargains and ideas

[macdeb]

Cool, my cars on stand, see you there

[Richard 858]

macdeb said:

Cool, my cars on stand, see you there

I'll see you there as well then Mac. Did you get my email about LMC 2016?

[macdeb]

Richard 858 said:

macdeb said:

Cool, my cars on stand, see you there

I'll see you there as well then Mac. Did you get my email about LMC 2016?

That will be cool Richard. No e-mail. Which one are you using? text if you like.

[davelittlewood]

Well I've checked the Lambda sensors on the sillyscope and they are working, sort of...




Not quite the nice square wave on Blitz' G33 website.

MAF isn't doing anything odd but as I've not a rolling road there's not much more I can do. Did find a crack in the wiring insulation on the MAF so a little work to tidy that up.

Just going to run it and then check the plugs in a few weeks.

[Bassfiend229hp]

davelittlewood said:

Drive home tonight.
Seemed a bit hesitant at first but once warmed up.

Lit up the rears in second just by planting right foot down on a good dry road.

At this rate it'll cost me more in rubber!!

This is what always annoyed me - all you guys talk about your cars squirming just under acceleration and breaking the arse loose or spinning wheels through the gears and mine never would.


Phil

[Sardonicus]

Bassfiend229hp said:

This is what always annoyed me - all you guys talk about your cars squirming just under acceleration and breaking the arse loose or spinning wheels through the gears and mine never would.


Phil

It will now

[Bassfiend229hp]

Sardonicus said:

Bassfiend229hp said:

This is what always annoyed me - all you guys talk about your cars squirming just under acceleration and breaking the arse loose or spinning wheels through the gears and mine never would.

Phil

It will now

Maybe ... we'll see ... the only loose arse I used to get was after too much cheese on my pizza!

Phil

[davelittlewood]

Vindaloo or hotter has the same effect!

[blitzracing]

davelittlewood said:

Well I've checked the Lambda sensors on the sillyscope and they are working, sort of...




Not quite the nice square wave on Blitz' G33 website.

MAF isn't doing anything odd but as I've not a rolling road there's not much more I can do. Did find a crack in the wiring insulation on the MAF so a little work to tidy that up.

Just going to run it and then check the plugs in a few weeks.

Whats the engine doing in the long non switching periods? is the idle still the same? Its worth bearing in mind that my car has no catalysts between the exhaust ports and Lambda probe, so there is no delay in getting the gas to the probe- unlike the TVR set up with pre cats that is inherently flawed as it slow down the feedback loop, especially at idle when the gas velocity's are slow anyway. Try running the engine at say 2000 rpm and see if the switching improves. In terms of general fuelling you need to check the long term trim and see whats its doing.