horrible hesitation issues... can anyone help?

[NIELSTTCOBRA]

hey everyone, the one issue i've had with this car is that it occasionally hesitates reallly badly under wot. keep in mind that i've got a return style fuel system so don't believe my problem is the same as the hesitation that plagues many other returnless cobras (please do correct me if i'm wrong).

just yesterday i took the car out to the track and it hesitated on both my passes worse than ever. it seems to get horribly rich and buck and hesitate, start to get going and pull like a raped ape, then do it all over again. any other turbo guys experience the same problem??? its now beyond aggravating, i just don't want to drive the car at this point till it gets fixed.

really hoping i can get a few turbo tuners in this thread... i hear hellioncobra has successfully tuned a large number of the turbo cars out there. any help would be very much appreciated.

heres a couple pics of my spark plugs. they are ngk tr6's gapped at 30

 

[NIELSTTCOBRA]

anyone???

 

[eebj01]

plug gap

Hello. The plug gap is probably too much. Try .026". That's what I'm running with the same TR-6 plugs with twin 67's. .030 is probably too much for that heat range plug. Thanks, Ed

 

[SCT2003]

I've experienced a hesitation a couple of times but not sure what is actually causing it??? It has happened maybe 4 times in the last couple of months since I went with a 2.8 & tune.

It only happens at WOT after shifting from 1st to 2nd or from 2nd to 3rd. Once I put it in the next gear and floor it, the car bucks and feels like it momentarily loses power and then goes right back to normal again.

I've hit the rev limited a couple of times since raising the boost but every time this particular hesitation occurs, I'm only shifting at about 6,000 RPMs or so...nowhere near the rev limiter!!!

Is this what's happening to you NIELSTTCOBRA???

I don't have an A/F/wide band/fuel pressure guage to monitor the fuel system but the car seemed fine at the Dyno. I'm pretty new to the S/C Cobra scene...what do you think is causing this guys???

Lean condition, belt slip, something else???

Later...Dave

 

[mustarrosa]

Could it be a tuning issue?

 

[SCT2003]

Could it be a tuning issue?

Not to hi-jack the thread but someone told me that my issue sounds like a PPRV problem. (check valve located in the gas tank by the fuel pump) A common fix is to remove the check valve and replace the stock "in-tank" hoses with better hoses. I'll look into this more...thanks!!!


Sorry again for "hi-jacking"!!!!

Later...Dave