2+2

IIRC, AC is not a factor here....the AC compressor is automatically turned off at full throttle....

Chris White

Nope.

Chris White

shaheed

like fast951 said, dyno it in 4th gear.

Ski

IIRC, didn't Jeremy get 3-4 consistent results out in AZ, with VR chips, DP wastegate, 3" exhaust, either 3 bar or AFPR...240-245/260-270 respectively? So you are very close to that, and get the gear that everyone has suggested for the next dyno run

Ryan in SD

I can feel a noticable differene when the AC is on...turn that shiznit off!

Also, have you checked to see if your cat is full of crap? I read somewhere on this forum that somebody couldnt see light through their cat after removing it....

Just for reference I put down 236hp and 242 ft-tq with just autothority chips + banjo bolt + (kn box filter)

Tom M'Guinn

Those numbers aren't so bad. Toss in a little 100 octane, sneak the boost up a bit, run it in 4th, turn off the A/C, maybe add a little timing via the FQS, and you'll see more power.

I made 355 to the wheels last time out with a bone stock exhaust and test pipe, so I second the point about your exhaust not being an issue.

mel_t_vin

on a minor side note to this thread, i was wondering if anyone has empirical data [hp, tq] comparing a test pipe to a hollow cat. does the expansion and contraction of the catalytic chamber actually create enough turbulent flow to significantly increase exhaust back pressure and decrease power output?

silverbullet

At this point I'm just wondering if it's worth it to keep trying to squeeze every last pony out of the k26, or save up and upgrade the turbo. That way I could be getting far more hp at a conservative boost setting. I can't imagine what a 320rwhp 951 is like, much less one with alot more. Geez, I can pull on stock LS1 F-bodies with only 232hp!

What cars would compare to a 951 with a k27/6 with about 320 to the wheels? Should that be similar to a C5 vette or 996, or faster? Just wondering (and fantasizing)....

special tool

Yeah really man - that is very good for an honest 15 psi k26.

fast951

Peak numbers are not that important. The overall shape of the power curve is VERY important, ypu want the largest area under the curve. To get more power, you will have to upgrade few more components and it gets $$. If your long term goal is to make lots of power, then pick your upgrades wisely so you can reuse them and not have to replace them in the future.

toddk911

"- Always dyno in 4th gear."

I know that is the rule of thumb as being closest to 1:1 ratio, but I have seen numerous runs that are WAY lower in 4th, vs. 3rd. Myself included. My run in 4th was 40+hp/tq less than in 3rd.

What do you think causes that John?

I know on the street 3rd always seems to "pull" harder then 4th also.

streckfu's

Lower gear ratio. The 4th gear ratio is the closest to matching the engine revolutions. 3rd gear may give you better numbers but they are not accurate (or not as accurate as 4th).

Remember that gears are torque multipliers and you want to use the gear that 'multiplies' the least.

toddk911

"What cars would compare to a 951 with a k27/6 with about 320 to the wheels? Should that be similar to a C5 vette or 996, or faster? Just wondering (and fantasizing).... "

I put down 318 to the wheels (still rough tune) but anyway pulled C5 easily from a dead stop and pulled a Saleen (SC281) from a roll. Can stay close to bikes on the intersate on top end runs. Just to give you an idea.

toddk911

So my car is making 40 LESS hp then I think?????

19psi, MAF, 3" cat back, LR Super 75 = 278 at the wheels???? Not sure about that one.

streckfu's

Did you make runs in 3rd and 4th gears? I'm sure someone can do the math to convert the power measured in 3rd to determine what it is in 4th but I can't.

How are you only getting 278hp with that set-up at 19psi? Aren't those turbos supposed be good for much higher peak numbers?