Dyno'd the car again today, last time I dyno'd I had my MSD digital 6 box installed, but I took that off between then and now.

Last year dyno:
216 hp, 266 tq

Same combo minus MSD Digital 6, a little bit hotter day:
206 hp, 260 tq

Take off the air cleaner:
211 hp, 263 tq

Put on air cleaner, close cutout (cutout it right after Y-pipe, so exhaust is run through Catco cat, Hooker Aerochamber cat back)
202 hp, 257 tq

Not comparing the two between last year and now, it's fairly clear that the exhaust side of the equation isn't as important for gains right now as the intake side is. Even the 14x3 K&N is a restriction on the system. The funny thing is, closing the cutout lost power EVERYWHERE on the curve. Maybe lower than 2000 it may have made more torque, but we always start pulls at 2000 rpm anyways so I really can't say (who races below 2000 rpm at the track? raise your hands!). The drop in power of the car could be a number of things, but I'm really not losing any sleep over it (I doubt it's the lack of MSD box, could be a number of things). Take it for what it's worth!

Tony

 

Good numbers, those are stock heads on there still? How did the AFRs look?

 

Stock heads, stock TBI (with ultimate job). AFR's were fairly stable in the 12.4-13.0 range, I didn't have my laptop there to mess with it but they were pretty close between all the runs.

 

Cool, sounds like you've got a fun car. They run great when they're all tuned in don't they? I'm very surprised by the practically negligible gains picked up through that cutout, especially since you're going through a cat. How much timing are you running full on? From what I've seen those swirl ports run best at pretty low timing, does your dyno time agree with that?

 

Well, between cutout open and closed you're looking at 5-6 hp on the top end at the wheels. I think I'm going to try and slap the MSD back on and see if it helps at all, that 5-6 could easily turn into more. Timing is pretty mild, only 26* total. Don't ask me why, could be my balancer slipped, but that's where I found the most power at.

 

NOPE, that is where you will find peak power on a swirl port head engine. 24-28* BTDC @ 3,600 rpm. You might find a couple more hp over 4,600 by bumping to 32* BTDC.

 

hey tonyc, i dont want to steal your thread but im in gilbert, az and was curious what shop you use for a dyno? i might want to do a few pulls on my truck. thanks.

 

getsideways,


Keith Schuster at AZ Dyno Chip
www.azdynochip.com
480-496-8800

and of course tell him that Tony with the Purple Beast Camaro sent ya
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Cool, I wasn't too concerned with the 26* but that helps to reaffirm it that someone else is getting the same results