Well I had my car in for a dyno day a month ago, car put down 380rwhp, 370rwtq...now today before I was going to spray the car, it was putting down only 355 rwhp, 360rwtq for a baseline NA run to make sure everything was ok. Both of these figures are corrected and the car was dyno'd on the same dyno at the same place. Today was over 13 degrees warmer ambient but since its corrected...this shouldn't matter right? The car runs just fine and pulls hard but just would like to know what may be going on here?

-Brian

 

Were the curves down all the way across the board or just your peak numbers?
Have you messed with the LT1 bellows lately? Are you sure it's correctly seated on the TB?
Could just very well be the dyno is out of calibration.

 

What springs you using? With all the 918's breaking threads it's at least worth a look.

 

The peaks are occurring at a almost identical rpm and the curve doesn't look any different. They said they did a software update since the dyno day where I made the higher numbers...so maybe this was the cause? At the dyno day, many cars were putting down close to what they did on other dynos similar to this one.

I am running the springs that are on the edelbrock heads so no 918s here.

-Brian

 

Did you do anything to prepare the car for the spray? Like pull timing or anything? Did he make the run with the system armed so it was pulling timing thinking he was going to spray? Could be springs were on the way out a month ago and now they are gone completely. It's weird how the HP is down a lot and torque was only 10.

 

Didn't pull any timing out of it and the way the runs went was as follows. First run was NA to make sure nothing was wrong and AF was still ok(noticed hp was down). Second run was a nitrous run but the juice didn't kick in until 4500rpm (should have hit at 3k but window switch wiring wasn't snug). Third run was the good run on the juice hitting at 3k to 6k rpm. Fourth run was supposed to be a Nitrous run but wiring came loose and it never hit (hp actually went up a few from the first NA run).

Nothing is telling me something is wrong mechanically really so I'm thinking the dyno was acting a bit funny. I dunno.

- brian

 

What was your HP with the 100 shot?

 

If your curves look exactly the same (just lower) then that maybe either some sort of induction blockage or their dyno. Check the path of your intake from filter to TB to make sure nothing is blocked up. However with this "update" it's very well likely the cause. No use really in taking it to a different dyno because you could get a completely different reading which wouldn't help your case at all.

 

466rwhp, 504rwtq

 

"They said they did a software update since the dyno day". This happened to me.

I had made 364rwhp and 370rwtq. A few weaks later back to the same dyno but with the software upgrades etc. Made 350rwhp and 365rwtq.