Nice bro!!! One sick Jeep you got there!!! Yeah something looks off on it and it could be belt slippage.... You see any signs of black rubber in the engine bay? What pulley you running now on the blower? Still the 3.2" or did you go to a 3.0? What does your AFR and look like in this run?
If it held 10-11 psi, then I wouldn't think belt slip, unless you were expecting more boost.
If it is an 11lb pulley setup for your motor combo, then you're just making the boost you're supposed to. Get a graph with boost reference and see if it climbs and falls or if it climbs and holds steady.
With centri blowers you'll see more boost with rpm, but realistically your graph looks normal-ish. Your torque plateaus before your HP peaks, which implies that you were still making power with RPM gain. Should it make power past 5500 rpm? That depends on the rest of the setup, I have no idea what cam you're running.
If the boost fell off, that would explain it, but steady 10-11 psi doesn't mean that it fell off at 5500rpm. If you were making 11psi at 5500 and 10psi at 6000, that still doesn't explain the 50jp loss.
Yes, about 12PSI on non-coated pulley and regular NAPA belt from what I could tell. But those were street runs and it was much warmer if that makes a difference.
I wonder if it's crank pulley slipping...
if you look carefully in the video you can see the belt rubber dust all over the SC bracket. no timing was pulled. also if you look at the video (part with the boost gauge) you can see boost start dropping toward the end of the pull.
in reality this was more of a base pull to see where we stand and also to make sure that the tune was good enough to continue messing with the car and testing things. on the first pull the car started to go a bit lean so luckily the tuner at PSI knew the system and was able to make few quick fueling adjustments to the Johan tune.
Some progress.
Got 3.0 non coated pulley and 108 3/4 Napa HD belt as well as a cobra adapter to move intake and use much bigger filter, possibly green filter used for GT-R setup.
Ah, and need to pin my crank pulley.
What?!! Pin before running again ASAP! Lol! Very interested in that cobra head you are rigging up. Keep up the good work, you are our boosted forged Procharger pioneer.
Pin that crank ASAP and do not get on the Jeep until you have it done or else you will damage that crank on your block.... Pin it first and then if you feel you need more Psi then go to the 3.0" pulley....
Sick jeep man! A little of topic but my cousin's husband is a co-owner at psi (Travis). We should meet up sometime I live about 10 minutes away from psi
So this is the jeep thats going to run JJ's trans am over, ill be looking for you on the blvd this summer. When ever you get it running right Ive got a DSM that's willing to run you for fun.
Your tail lights are identical to the ones I ran for a couple of years.
Did you see Ruffjat updated his "lil build update" with 13# of boost dyno numbers? I know dyno doesn't really mean shit it's all about the track but 695 HPwith his 393 is giving me huge hope for his build.
Did you install the kit yourself or the shop that did the Dyno season for you? If the shop installed it then I would take it back for them to pin the crank for you since already payed for it when doing the install. I believed the ATI dampener has a keyway in it that's made to fit with a Manley Forged Crank... Do you have a stock crank or Manley forged crank?
it was on dyno shops blog and their logo was in it. got complaints for allegedly promoting street racing due some pulls on a closed course at the end of the dyno video. it will be reuploaded i am told.
on another note. are there any 18 inch base model jeep wheels that clear the back brakes. i want to put some 18" DRs on this thing and hit Atco later this month.
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