Gear and CAI - No Improvment?

[Sledder]

This is similar to 5 Oh Brian’s thread but not wanting to hijack I thought I would post a separate thread.

Car is a 2012 GT Auto with drag radials. The car's drag racing history from stock to this point is here:
http://www.s197forum.com/forum/showthread.php?t=62551

Went from the stock 3.15 to a 3.73 gear and at the same time added a C&L cold air intake. Car was dyno tuned with the new setup making 7 lbs more tq and 18 more HP. After 2 different trips to the track with different tunes there is no difference in performance between the gears. I mean nothing from one end of the track to the other. Rather than post time slips I inserted a report from RACER IQ. 6/6 run is with 3.15 gear, 9/26 is with the 3.73.

Current tune is from Lund. Previous tune did give me a couple of good runs (12.80s) but was prone to throwing wrenches and codes (PO61B) when I would accelerate but that’s another story. Lund tune is smooth as silk with no drivability problems. Gear changes are at 7,000. Going through the lights around 6000 rpm in fourth gear.

I was hoping for a significant improvement with the new gear.. What has me confused is there is absolutely no change. I thought if anything I might at least pick up something in the 1/8 but as you can see the runs are almost identical. In fact when comparing corrected times I slowed down.

I am wondering if I am missing something? Exhaust is stock is that holding it back? Is something else holding it back? Lund has been great but right now it is an e-mail tune. Would I benefit from their remote tune?

As always thanks for your input.

 

[iceguyb14]

This is similar to 5 Oh Brian’s thread but not wanting to hijack I thought I would post a separate thread.

Car is a 2012 GT Auto with drag radials. The car's drag racing history from stock to this point is here:
http://www.s197forum.com/forum/showthread.php?t=62551

Went from the stock 3.15 to a 3.73 gear and at the same time added a C&L cold air intake. Car was dyno tuned with the new setup making 7 lbs more tq and 18 more HP. After 2 different trips to the track with different tunes there is no difference in performance between the gears. I mean nothing from one end of the track to the other. Rather than post time slips I inserted a report from RACER IQ. 6/6 run is with 3.15 gear, 9/26 is with the 3.73.

Current tune is from Lund. Previous tune did give me a couple of good runs (12.80s) but was prone to throwing wrenches and codes (PO61B) when I would accelerate but that’s another story. Lund tune is smooth as silk with no drivability problems. Gear changes are at 7,000. Going through the lights around 6000 rpm in fourth gear.

I was hoping for a significant improvement with the new gear.. What has me confused is there is absolutely no change. I thought if anything I might at least pick up something in the 1/8 but as you can see the runs are almost identical. In fact when comparing corrected times I slowed down.

I am wondering if I am missing something? Exhaust is stock is that holding it back? Is something else holding it back? Lund has been great but right now it is an e-mail tune. Would I benefit from their remote tune?

As always thanks for your input.

That is odd. The gears should help your 60'. Try launching a little harder on those drag radials. The cai won't help your et much bc of more heat soak.

Sent from my SAMSUNG-SGH-I727 using Tapatalk 2

 

[Five Oh Brian]

Wow, you did slow down a bit. Better DA and cooler weather should have helped even without the gears & CAI. Maybe the email tune is too rich for the CAI and some leaning out and a little more timing would fix it??? Any idea what your air/fuel ratio is and how much timing Lund put in your tune?

 

[Sledder]

Any idea what your air/fuel ratio is and how much timing Lund put in your tune?

No idea what the air/fuel and total timing is. Talked with them via their support site and was advised I could put in 2 degrees more global spark to make it more aggressive at the track.

 

[kdanner]

I've tested too many CAIs that all gained nothing at the track on these cars, so I'll leave that out of any thoughts on this. So worse air with a worse 60' before, and the rest of the way down it was quicker. The extra gear change has to be part of this. That's a 28" tire, and if you're going to limit yourself to 7000 RPM, a 3.31 gear can run 116 MPH in 3rd. I'd really like to see more like 7300 RPM on your shifts/traps, then the 3.31 would be good for 121 MPH in 3rd.

 

[Five Oh Brian]

No idea what the air/fuel and total timing is. Talked with them via their support site and was advised I could put in 2 degrees more global spark to make it more aggressive at the track.

That right there tells me that they know they left the tune a little rich if it can handle more spark. I thought about adding a couple of degrees of timing to my tune at the track the other day, but didn't want to risk any detonation without datalogging first. You may want to datalog to see what you can learn about your tune and adjust from there.