2.8 pulley change-out

[mean04]

I just put a 2.8 pulley on and had a dyno tune done on the chip. However, I only gained 30rhp instead of the 60-70 advertised.

My fuel-to-air is around 11.5. Is this what it should be. If I remember it was in the 12's before.

 

[Silver03]

What were the peak numbers after the pulley? Post a dyno graph if you can.

 

[4.6modular]

What was peak timing? You could safely tune the A/F at 11.8-11.9 if your timing is conservatively 21 maybe 22 degrees on 93 octane. This would net an increase in numbers.

 

[mean04]

I have to figure out how to attach the dyno reading.

When the car had about 4k on it I put on BBK long tube headers, BBK x pipe, flowmaster catbacks, and an K&N FIPK filter. Did a dyno and came up with 410rhp and 390 # of torque. The peak hp came at 6100rpm.

Last week I put on a 2.8 pulley and had a reputable dyno place do a computer tune. I was expecting about a 60hp increase as I've read everywhere. However, I only got 440 rph and 470 # of torque. ??

I'll post the graph as soon as I can.

 

[mean04]

Forgot to add: the AF mixture looks like between 11.5 and 12. And I running about 14 max # of boost now.

Also, my gas mileage went up from 17.9 to 21.7? Maybe the optimized tuning?