Undecided...What's the best SC kit for a '91GT?
#46
Tim Murphys' 88 S4: http://www.murf928.com/forum/viewtopic.php?f=7&t=14
0-60 in 3.799 sec amd 1/4 mile at 11.499 sec
Perhaps the biggest challenge with a SuperCharged 928 won't be the evo or the wrx but will be the excessive wheel spin...
0-60 in 3.799 sec amd 1/4 mile at 11.499 sec
Perhaps the biggest challenge with a SuperCharged 928 won't be the evo or the wrx but will be the excessive wheel spin...
How much boost are you guys running and how much boost with stock style head gasket?
Last edited by inactiveuser1; 12-28-2009 at 08:49 PM.
#47
Rennlist Member
While compressor mapping and sizing in important for maximum area under the power curve, what about engine management? Coming from the 951 world fuel, timing, etc. is much more important to both power and dependability, especially when pushing the compression ratio limits of pre-detonation.
#48
Rennlist Member
While compressor mapping and sizing in important for maximum area under the power curve, what about engine management? Coming from the 951 world fuel, timing, etc. is much more important to both power and dependability, especially when pushing the compression ratio limits of pre-detonation.
928s - poor fuel mapping, inability to run large injectrors, and no real knowledge of how near detonation they were.
The Murf Stage 3, 928 Specialists Twinscrew and the Kuhn Twin Turbo all used the SharkTuner to accurately remap both fuel and ignition for optimum safe results.
#49
Rennlist Member
I am unfamiliar with the 928 setups...
In the 951 world increasing the flow with bigger turbos and more boost meant you had to increase not only the injector size to keep the duty cycle and fuel pressure within sane values, but also the MAF size and/or calibration so the 0-5 voltage output of the MAF represented the new increased flow. If this wasn't done properly the Chips would never sense the motor was under load and would not advance timing correctly. This was a big time discovery when I was tuning my 951 a couple of years ago. The bigger turbos and all made a bunch more power when the load maps worked correctly with the MAF voltage outputs to advance timing.
Am I correct in assuming SC kits and Shark Tunered Chips have this already worked out by now?
In the 951 world increasing the flow with bigger turbos and more boost meant you had to increase not only the injector size to keep the duty cycle and fuel pressure within sane values, but also the MAF size and/or calibration so the 0-5 voltage output of the MAF represented the new increased flow. If this wasn't done properly the Chips would never sense the motor was under load and would not advance timing correctly. This was a big time discovery when I was tuning my 951 a couple of years ago. The bigger turbos and all made a bunch more power when the load maps worked correctly with the MAF voltage outputs to advance timing.
Am I correct in assuming SC kits and Shark Tunered Chips have this already worked out by now?
#50
Rennlist Member
Yes, these issues are properly addressed. The Kuhn twin turbo relates closest with your 951 experience.
He uses a SMAF (to extend the available load range) which has a special SharkTuner fuel maps, and this works with a similar wide load range EZK map for the ignition.
http://www.kuhnperformance.com/main.php
He is making 550rwhp at 12psi.
He uses a SMAF (to extend the available load range) which has a special SharkTuner fuel maps, and this works with a similar wide load range EZK map for the ignition.
http://www.kuhnperformance.com/main.php
He is making 550rwhp at 12psi.