In May I had my car dyno'd on a portable dyno operated by Mid Atlantic Dynosports at the Wildwood Classic Car Show in Wildwood, NJ and got the following numbers :
The only mods to the car at that time were: air silencer removed, K&N panel filter, FMS shorty headers, 2.5" MAC cat pipe, 2.5" Flowmaster Force II exhaust, FMS aluminum driveshaft. Timing was set at 14*, fuel pressure was stock (stock regulator).
Pull #1) 216.5 hp @ 4500 rpm - 282.8 tq @ 3500 rpm
Pull #2) 218.8 hp @ 4500 rpm - 284.6 tp @ 3500 rpm
The Wildwood Car Show is twice a year (May and September), and since M.A.D said they were going to be back in September I thought I could get a nice "before and after" reading knowing I would be performing the following mods over the summer: Densecharger Cold Air Kit w/ K&N cone filter in the fenderwell, 65mm TB, 67mm EGR, Ported Stock Upper, Tmoss Ported Stock Lower, new 19lb injectors, Kirban AFPR, Ported E7's, FMS 1.6 Roller Rockers, Summit Off Road H-Pipe, Magnaflow Exhaust, Performance Distributers "Firepower" Ignition Kit. Timing was set at 14*, at fuel pressure was set at 46 psi (off and plugged).
Upon arrival at the show I found a different company "Axcelerated Motorsports" running the dyno this time.
Pull #1) 218.4 hp @ 4900 rpm - 272.1 tq @ 3600 rpm (46 psi FP)
Pull #2) 221.3 hp @ 5000 rpm - 273.9 tq @ 3700 rpm (47 psi FP)
I am confused about a few things. My air/fuel ratio on the first run went from 13.4 @ 2200 rpm to 11.8 @ 5700 rpm. I could be wrong but isn't that way too rich for an N/A motor? On the next run they had me increase my FP which I did (one pound) and my hp/tq went up albeit slightly, HOWEVER based on the readout, my air/fuel ratio was actually leaner going from 14.2 @ 2200 rpm to 12.4 @ 5400 rpm (he shut it off a little earlier on the 2nd run). I was running the stock fuel pump (I am going to replace it with a 190lph), which I think may have been unable to keep up causing the leaner reading under the higher pressure.
My questions are:
1) Isn't that a/f ratio too rich for an N/A motor?
I've read 13.0 to 13.5 for N/A motors, 12.5 to 11.0 for blowers/nitrous/turbos etc...
2) What variables come in to play when someone dyno's your car?
Can the dyno, operator, software, calibration, affect it?
I mean if that's all the hp/tq I have then so be it, but it would be very surprising to me that the before and after results would be so similar.
The only mods to the car at that time were: air silencer removed, K&N panel filter, FMS shorty headers, 2.5" MAC cat pipe, 2.5" Flowmaster Force II exhaust, FMS aluminum driveshaft. Timing was set at 14*, fuel pressure was stock (stock regulator).
Pull #1) 216.5 hp @ 4500 rpm - 282.8 tq @ 3500 rpm
Pull #2) 218.8 hp @ 4500 rpm - 284.6 tp @ 3500 rpm
The Wildwood Car Show is twice a year (May and September), and since M.A.D said they were going to be back in September I thought I could get a nice "before and after" reading knowing I would be performing the following mods over the summer: Densecharger Cold Air Kit w/ K&N cone filter in the fenderwell, 65mm TB, 67mm EGR, Ported Stock Upper, Tmoss Ported Stock Lower, new 19lb injectors, Kirban AFPR, Ported E7's, FMS 1.6 Roller Rockers, Summit Off Road H-Pipe, Magnaflow Exhaust, Performance Distributers "Firepower" Ignition Kit. Timing was set at 14*, at fuel pressure was set at 46 psi (off and plugged).
Upon arrival at the show I found a different company "Axcelerated Motorsports" running the dyno this time.
Pull #1) 218.4 hp @ 4900 rpm - 272.1 tq @ 3600 rpm (46 psi FP)
Pull #2) 221.3 hp @ 5000 rpm - 273.9 tq @ 3700 rpm (47 psi FP)
I am confused about a few things. My air/fuel ratio on the first run went from 13.4 @ 2200 rpm to 11.8 @ 5700 rpm. I could be wrong but isn't that way too rich for an N/A motor? On the next run they had me increase my FP which I did (one pound) and my hp/tq went up albeit slightly, HOWEVER based on the readout, my air/fuel ratio was actually leaner going from 14.2 @ 2200 rpm to 12.4 @ 5400 rpm (he shut it off a little earlier on the 2nd run). I was running the stock fuel pump (I am going to replace it with a 190lph), which I think may have been unable to keep up causing the leaner reading under the higher pressure.
My questions are:
1) Isn't that a/f ratio too rich for an N/A motor?
I've read 13.0 to 13.5 for N/A motors, 12.5 to 11.0 for blowers/nitrous/turbos etc...
2) What variables come in to play when someone dyno's your car?
Can the dyno, operator, software, calibration, affect it?
I mean if that's all the hp/tq I have then so be it, but it would be very surprising to me that the before and after results would be so similar.