72turboz

New plugs were in the car, we even pulled them and inspected them during the dyno session. Everything was good, used non projected tip plugs as well as one step colder. Gapped 0.028 if I remember correctly. Will begin the process of replacing cam and having a 3 inch exhaust installed then heading back to the dyno shortly after.

Yes and that’s what the lower psi runs showed. He found peak torque made adjustments and tuned around it. Like I said the graphs moved up from there till it hit a wall and any increase above 13psi did not net any gains.

Wasn’t identical as he was adjusting each pull. But power and torque were increasing with variations on where peak was until 13psi. I strongly think the cam specs are the main culprit coupled with the 2.5 exhaust from downpipe back.

I don’t have access to any other dyno sheets, but I can assure you the curve was trending upwards as it should till around 13psi where it failed to make any gains. The cam was degreed correctly, I verified with a wheel, was my first thought initially as well.

Gaps are good, and coil is strong, new msd. No break up in the higher rpm’s afrs not going rich with unburnt fuel.

To be fair I destroyed the first crank in my block.

Thanks for the link. I’ve read that post extensively. I figure I’ll replace the cam so it’s where I’ll be doing most of my driving and get a 3 inch mandrel exhaust out the back. I’ll take care of some smaller items like adding an idle air control valve to the car for cold starts and when the electric fans kick on. Cars almost ready just is frustrating with the power figures.

The only reason I rebuilt/refreshed the block was because it suffered a blown head gasket, and spun a crank bearing pretty much destroying the crank surface. Since I was having to replace it anyways I spent a little extra so I was happy with it. As far as the lower boost runs I don’t have pictures of those, but I do remember that the curve was slowly moving up as we turned up boost until roughly 13psi where it stopped making any power. As far as spark the car was not breaking up at all, and we were running one step colder plugs gapped at 30 and used non projected tips. Tuner didn’t seem to think it was spark related. I have no doubt that I’m running into some kind of restriction I just don’t know where it’s happening at.

Thanks for the thread link, I read through it awhile ago and I’ll read through it again. Might just be the nature of the beast with this engine. As far as the engine goes it’s a built/refreshed long block. Bottom end and top end have been gone through, replaced crank, balanced, bored over etc. only weak spots left are probably the pistons and if those go I’ll replace with forged flat tops. Im hungry for the 300whp number, although the car drives great and is a blast in its current state. Next time I’m on the dyno with the new intake, exhaust and cam I’ll bump the boost to 18psi to see if I can’t get anything more out of it.

Adding boost and or adjusting timing doesn’t affect the curve in anyway. Stays relatively the same. Running out of something somewhere. This was at 12 psi if I’m not mistaken.

Trying to upload a picture of the dyno graph but it keeps inserting upside down.

The heat shields are bolted to the underside of the intake manifold and bolted to the exhaust manifold you can’t see them in the picture. The IAT sensor is on the intercooler piping right before the throttle body, you can see it standing straight up. It’s right before entering the intake. I don’t think it’s heat soak, dyno pulls we’re done with ambient temps in low 80’s here in socal.

I miss spoke, having the tuner send me a picture of one of the runs the torque does fall off, he’s sending me a picture of the final 12 psi run, again adding boost up to 16 psi did not yield any gains.

Roughly what the engine looks like, something’s have been replaced or tweaked since this picture was taken but overall what how it looks.