rev 3 misfire on boost.

[kev8611]

My rev 3 is misfiring on boost but only when its fully warmed up.

As above. Fully forged. Compression tested and 152. 160. 158. 160

running a power fc and sard 800cc with a gt3076. Ebay sidemount and gtschris fan and shroud.

All ignition components have been replaced and running bkr7e's

Obviously cylinder one is slightly lower on compression and funny enough thats the one that when I take the plug out it is wet where as the rest are dry.

I have adjusted timing on the commander to sort out knock etc and the most im getting is high 20's. Air fuel ratio on boost is 11 to 11.5

I know I have probably answered most my own question and it points towards an issue with cylinder one but anyone got any idea as to why it does it only when its fully warmed up?

Thanks

[Odin_S]

I'm thinking from your previous posts, your car needs mapping properly

[Shmed]

Have you got a fuel pressure regulator? I had a misfire on mine, mainly when warm, and it was due to the FPR bolt loosening off and dropping my base pressure.

I think mine manifested as an 'only when warm' prblem, because my ECU was set to 'limp' when cold, so wouldn't actually let me put too much power down when the engine was cold.

[kev8611]

Yeah I have a regulator fitted. Gauge says just under 40psi primed and just above 30 psi when running.

I understand with my car needing mapped but air fuel seems ok and its not showing alot of knock. I am hoping it is not a mechanical problem.

Thanks

[kev8611]

Could the ignition components be breaking up when the engine is hot and causing a weak spark? afterall it is just standard leads and distributor etc and just bkr7e's.

If this is a possibility then what can i do to these components to produce a better spark under load? ignition amplifier? different leads?

Thanks again

[Odin_S]

I say you're doing damage to you car with a DIY map. At the very least its gonna run crap but at worse its detonating...

Save up and get Ryan for 2bar to map your car, end of story

[kev8611]

Im aware the car will need a proper map but I wouldnt say knock at its highest of 27 or 28 is detonation considering the power fc warning is 60.

As I say it seems to be fuelling fine but just misfires under heavy load once fully warmed up.

If I try get the car mapped and it turns out there is another issue needing addressed then im throwing money away for nothing. Just asking what others think about the compression figures and the ignition components thoughts.

Unfortunately im up north so would need to be someone up here to map it. Luckilly i have found a power fc mapper about 20 minutes from me