For those of you that saw my previous post, I've been working hard to get the most out of my Whipple 2.9 setup on my 2010 GT500.
My setup consists of:
Stock long block and cams
Whipple 2.9L w/ 2nd generation rotors and Crusher plenum
Whipple 123mm MAF and CAI
L&M Dual 66mm Throttle Body
Dynatech 1 7/8" Longtube headers w/ 3" collectors
Dynatech 3" off-road X-pipe
Magnaflow Magnapack 3" catback exhaust
Innovators West 10% Overdrive Harmonic Balancer
72lb Fuel Injectors
Kenne Bell Dual BAP
NGK TR6 plugs gapped at 0.030"
Snow Performance Meth/water injection
Afco Dual Fan/Dual Pass Heat Exchanger
3.73 gears
DSS 1-piece aluminum driveshaft
too many other suspension/misc. mods to list
A couple of weeks ago I posted that I had made 753 RWHP @6400rpm and 760 RWTQ @3900 rpm with a 3" upper pulley and a 93/Torco custom tune at 21psi boost. This was on a Mustang Dyno, that I suspect is set up to give numbers similar to Dynojet numbers. I also posted that we were working up a C16 tune with a 2.7" upper pulley at 24 psi boost that made 830 RWTQ but we had to abort the run at 5500 due to ignition breakup and only saw 776 RWHP because of that. The ignition breakup was later determined to be caused by the N2MB WOT box that I had installed recently.
Anyway, I got the car back on the dyno today. On the C16 tune, the car made 793 RWHP @6250rpm and 818 RWTQ at 4200rpm at 23-24psi. It seemed that the HP curve leveled off, which is something that these motors don't do. Normally, peak horsepower with these motors is as high as one dare rev it. The ignition breakup was gone. AFRs were good, and the car wasn't maxing out the current fuel system. The 123mm MAF seemed to do the trick, as MAF voltages were not pegging. IAT2s didn't go over 115. I suspect that the supercharger belt may have started to slip slightly. I also wonder if it would have continued to make more power with an L&M 72mm Dual TB or a Whipple Monoblade.
While continuing to tempt fate with the stock longblock, we worked up one last tune. We kept the 2.7" upper pulley and the C16, but we added a 75hp shot of nitrous via a ZEX wet system. The window switch was set to spray from 3200 to 6000 which yielded only 846 RWHP at 6000rpm, but a whopping 978 RWTQ at 3700. :rockon:The problem with this run was apparently that amount of torque combined with Goodyear Eagle F1 Supercar tires is not conducive to maintaining traction with the dyno rollers. :shrug:
Even without the nitrous, I think that there is still some more power to be had from the Whipple 2.9. I will likely go back and install a slightly shorter blower belt or install an auxillary tensioner. I will also likely try a larger throttle body. I've contemplated removing the lower intake and having it ported and installing a VTS intercooler with heat shields. I would like to have a built motor on standby before I go much further, as the stock internals in mine are already near their limit. It's unlikely that I would go to the trouble of changing cams or removing the heads to port them without also changing up the shortblock and stepping up to a larger blower.
My setup consists of:
Stock long block and cams
Whipple 2.9L w/ 2nd generation rotors and Crusher plenum
Whipple 123mm MAF and CAI
L&M Dual 66mm Throttle Body
Dynatech 1 7/8" Longtube headers w/ 3" collectors
Dynatech 3" off-road X-pipe
Magnaflow Magnapack 3" catback exhaust
Innovators West 10% Overdrive Harmonic Balancer
72lb Fuel Injectors
Kenne Bell Dual BAP
NGK TR6 plugs gapped at 0.030"
Snow Performance Meth/water injection
Afco Dual Fan/Dual Pass Heat Exchanger
3.73 gears
DSS 1-piece aluminum driveshaft
too many other suspension/misc. mods to list
A couple of weeks ago I posted that I had made 753 RWHP @6400rpm and 760 RWTQ @3900 rpm with a 3" upper pulley and a 93/Torco custom tune at 21psi boost. This was on a Mustang Dyno, that I suspect is set up to give numbers similar to Dynojet numbers. I also posted that we were working up a C16 tune with a 2.7" upper pulley at 24 psi boost that made 830 RWTQ but we had to abort the run at 5500 due to ignition breakup and only saw 776 RWHP because of that. The ignition breakup was later determined to be caused by the N2MB WOT box that I had installed recently.
Anyway, I got the car back on the dyno today. On the C16 tune, the car made 793 RWHP @6250rpm and 818 RWTQ at 4200rpm at 23-24psi. It seemed that the HP curve leveled off, which is something that these motors don't do. Normally, peak horsepower with these motors is as high as one dare rev it. The ignition breakup was gone. AFRs were good, and the car wasn't maxing out the current fuel system. The 123mm MAF seemed to do the trick, as MAF voltages were not pegging. IAT2s didn't go over 115. I suspect that the supercharger belt may have started to slip slightly. I also wonder if it would have continued to make more power with an L&M 72mm Dual TB or a Whipple Monoblade.
While continuing to tempt fate with the stock longblock, we worked up one last tune. We kept the 2.7" upper pulley and the C16, but we added a 75hp shot of nitrous via a ZEX wet system. The window switch was set to spray from 3200 to 6000 which yielded only 846 RWHP at 6000rpm, but a whopping 978 RWTQ at 3700. :rockon:The problem with this run was apparently that amount of torque combined with Goodyear Eagle F1 Supercar tires is not conducive to maintaining traction with the dyno rollers. :shrug:
Even without the nitrous, I think that there is still some more power to be had from the Whipple 2.9. I will likely go back and install a slightly shorter blower belt or install an auxillary tensioner. I will also likely try a larger throttle body. I've contemplated removing the lower intake and having it ported and installing a VTS intercooler with heat shields. I would like to have a built motor on standby before I go much further, as the stock internals in mine are already near their limit. It's unlikely that I would go to the trouble of changing cams or removing the heads to port them without also changing up the shortblock and stepping up to a larger blower.
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