I
Have an head/port 07 M8 that had an awesome clutching setup for 8-12K altitude. Smooth engagement, snappy upshift at any RPM, held RPM on hill, good/controlable backshift, decent track speeds. Now added an SLP pipe and chasing the optimum setup.
Before;
Primary Spring - AC yellow/Wht
Weights - 68.1gr Cutler adjustables
RKT 36deg secondary kit, red spring, center hole (#4)
7900-8000 Max RPM on a hill pull
With the new pipe, seeing much more top end power but lost low RPM snap. Finished tuning the fuel map .. now chasing the clutch setup. Targeting max RPM 8000-8100.
Leaving the current setup and adding/subtracking to the weights, yet to see over 7940 RPM (per BD box):
1) adding weight, drops RPM into the 7800's but adds back some low end snap (upshift).
2) removing weight, raises RPM into 7900's but no more snap (see#4).
3) tried stiffening secondary spring, while changing the shift pattern a little, not much change to the RPM (of course).
4) <6000RPM, feels like a delay in the upshift. Engine increases RPM, but the clutches do not upshift fast enough to take advantage of the power curve .. if that makes sence ... no snap.
5) >6000RPM, pulls like a madman, but at ~7900RPM max have a few more ponies I'm not taking advantage of.
Thinking I need to go with a higher finish rate on the primary spring.
Any opinions on a Speedwerx H5? Any suggestions for spring rates that have worked in simular applications?
Oh, and I'm going to gear down slightly, so I could probably get more agressive on the engagement, if needed.
Other ideas?
BTW, this engine setup is fantastic for the M8. Just need the clutching setup to take advantage of it.
Before;
Primary Spring - AC yellow/Wht
Weights - 68.1gr Cutler adjustables
RKT 36deg secondary kit, red spring, center hole (#4)
7900-8000 Max RPM on a hill pull
With the new pipe, seeing much more top end power but lost low RPM snap. Finished tuning the fuel map .. now chasing the clutch setup. Targeting max RPM 8000-8100.
Leaving the current setup and adding/subtracking to the weights, yet to see over 7940 RPM (per BD box):
1) adding weight, drops RPM into the 7800's but adds back some low end snap (upshift).
2) removing weight, raises RPM into 7900's but no more snap (see#4).
3) tried stiffening secondary spring, while changing the shift pattern a little, not much change to the RPM (of course).
4) <6000RPM, feels like a delay in the upshift. Engine increases RPM, but the clutches do not upshift fast enough to take advantage of the power curve .. if that makes sence ... no snap.
5) >6000RPM, pulls like a madman, but at ~7900RPM max have a few more ponies I'm not taking advantage of.
Thinking I need to go with a higher finish rate on the primary spring.
Any opinions on a Speedwerx H5? Any suggestions for spring rates that have worked in simular applications?
Oh, and I'm going to gear down slightly, so I could probably get more agressive on the engagement, if needed.
Other ideas?
BTW, this engine setup is fantastic for the M8. Just need the clutching setup to take advantage of it.
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