OK… my car was making 450 on pump last year but the block truw a rod so I had to re-built the motor.The only thing tha change was the crank, I switch from the gsr to the ls crank, for this year. But my problem is that today I put my car on the dyno to see if everything was fine and the car is making way less power from last year setup at the same psi…is it because im using the tune from the other motor or what?
A/F is fine 11.7
timming is fine 16:banghead::banghead::banghead::banghead::banghead::banghead:
???
i actually had a DREAM about your car last night. In the dream you were getting a lot of blowby on cylinder 1. That’s all i can add sorry. haha.
so you changed from gsr crank to ls crank? did you change the rods as well considering that they have a different stroke? I would check for bent valves if you tried to used the gsr rods with the ls crank. are you using the same block or a different one.
Wouldn’t an ls crank with gsr rods drop the piston much lower because of the longer ls crank stroke? Thus making your compression ration plummet? I’m not sure if I’m using the correct terms but it makes sense in my head lol.
^ yes it would
check compression and get back to us
the ls and gsr rods are a different length silly
you shoulda jus called me up cuz i know everything 
The ls crank would lower the compression…
MOOO BOOOSTT 
Its not making as much power because:
LAS GOMAS DE AFRENTE SON GRANDOTAS 
jaja
The gsr rods are longer then the ls rods since the gsr crank has less stroke. gsr rods plus ls crank plus gsr/ls block equals pistons hitting the head or very high compression. if your not kissing valves then your compresion is stupid high and your probably detonating ALOT which is why your not making power. either way i would expect this motor to maybe last half as long as the previous unless you fix the problem.
yeah I change the rods,pistons and the block
compression 180 across
maybe boos leak?
def a possibility, did you get it tuned or just throw it on there? with the dif stroke it will definetly need a retune
no tune just put it on the dyno
post up both dyno sheets with boost plots a/f etc
i’m a bit confused…
that the only thing that’s diferent is the crank the rest is new but is the same as before
retune
well the LS and GSR crank have different strokes. So my guess is you either need a new tune, or you have a hand full of bent valves.
I’d do a compression test to make sure everything is straight and if that checks out get a new tune to adjust for the change.
lol wat?
post #11 = :lol:
Yeah, I’d def take it to a reputable tuner and see what’s going on with the car. You changed a lot to just go off the same tune I’d say.