don_w

JBA Racing will be installing my new 4.10 gears tomorrow (Wed, 7/6). I can't wait! But before they do, I'm going to have them dyno the car with the CAI & Predator tune. It will be interesting to see what the numbers are.

757GT

I'm getting mine dyno tuned tomarrow also. Good luck.

don_w

I just replied to your other post... let's compare numbers tomorrow.

discofan

Dear Don,

Good Luck on your 4.10's...

Let me know how they feel w/your automatic...

I'm scheduled for 3.73 install on July 12th...

I chose that gear because "the man" told me that with a supercharger (which I will have installed sooner than later), the 4.10 would be too much gear for my automatic...

Can't wait to hear from you...

Dave

hawgman

Hey Don, they just doing a dyno pull or doing a dyno tune? Man, I thought the canned tunes rocked until I finally had someone that knew what they were doing do a tune on the car. Much impressed.

don_w

Just a dyno pull today. JBA recommended I wait until I install the SC before I spend the extra bucks on the dyno tune. However, based on the so-so dyno results I got this morning, I may reconsider.

According to today's pull, I only gained about 13 rwhp with the CAI/Predator, but the torque went up by a whopping 45 ft/lbs. So, the seat-of-the-pants performance I feel with the CAI/Pred setup seems to be torque related rather than horsepower.

Anyway, here are the before/after numbers:

STOCK:

257 rwhp @ 5690 rpm
274 ft/lb tq @ 4246 rpm
Temp was 60F. A/F ratio stayed between 11.4 - 11.8 from 4000-5700rpm.

C&L CAI/Predator:

270 rwhp @ 5634 rpm
319 ft/lb tq @ 3894 rpm
Temp was 64F. A/F ratio stayed between 12.4 - 12.9 from 4100-5900rpm.

There were also a couple interesting items of note.

First, they made both of these pulls in 3rd gear (not 4th, which is a 1:1 drive ratio). It seems, they couldn't keep the auto tranny from downshifting when they hit the throttle in 4th. However, during a full dyno tune session, they have a way to electronically "lock" the tranny in 4th gear.

I also asked about the correction factor for the Dyno Dynamics system they use. They said that it uses a correction system that will result in lower numbers than say a DynoJet. In fact, JBA has tested both systems. Using a test car, they made a pull on their own dyno and then immediately took it to another shop who uses a dynojet for a comparison pull. The pulls were made about 30 minutes apart, and the dynojet reported about 20 rwhp more than their own dyno. So, comparing numbers between two types of dynos is really an apples and oranges situation. The main thing is repeatability on any given dyno. For determining performance gains due to mods or tuning, doing them on the same dyno is more important than the actual numbers.

biged3

I thought the Predator and C&L were supposed to give you 26.0 RWHP and 22 ft/lbs of torque.

Hey Don at least you got close to double on the torque.

don_w

Well, that's what their ad says anyway... [] I'm also wondering what effect the 3rd gear pulls had on the numbers.

flyingt

This is becoming an interesting topic. It would be nice to see the final outcome to this. Don Im with you maybe pulling in third gear had something to do with the torque.

don_w

The original baseline was done in 3rd also, and the torque numbers then (273 ft-lbs) seemed reasonable.