Launch RPM

weedburner · 10-17-2016, 01:10 PM

If you want less bog, i would recommend reducing your clutch's clamp pressure to more closely match your engine's power. That will raise your engine's average rpm, which means your engine will be able to produce more power over the same amount of time. It also reduces the amount of torque your clutch will draw on launch and after the shifts, which will help keep your M22 alive.

On launch, less clutch slows your rate of rpm loss when you dump the clutch, so it takes longer for engine rpm to drop far enough to sync up with wheel speed. By delaying the sync’ing of engine rpm and wheel speed (clutch lockup) to a point farther down the track, the car will have had more time to accelerate so it will be traveling faster. Basically, rpm won't dip as low because the car will be traveling faster when things sync up. Same thing happens after the shifts, which means recovery rpm will be better after all the shifts down the track. It all adds up to the engine being able to pack more revolutions of power production into the run. A 500 rpm improvement on after shift recovery is not uncommon with a well matched engine/clutch package.

If you simply air up the tires until they spin you will get much the same effect on launch, but there will be little if any spin after the shifts which means engine rpm would get dragged down lower after the gear changes, effectively lowering your average rpm. Adding air also reduces traction which helps your M22 live thru the launch, but since the tires won't likely spin after the shifts, your M22 would then still suffer the full hit from your current clutch.

The benefits of lower clamp are not limited to those with adjustable clutches. Fast Coyote Stock guys have it figured out, using non-adjustable diaphragm clutches with great success...

10-17-2016, 01:10 PM	#5
weedburner Junior Member Join Date: Apr 2016 Posts: 55 Likes: 1 Liked 20 Times in 16 Posts	Re: Launch RPM If you want less bog, i would recommend reducing your clutch's clamp pressure to more closely match your engine's power. That will raise your engine's average rpm, which means your engine will be able to produce more power over the same amount of time. It also reduces the amount of torque your clutch will draw on launch and after the shifts, which will help keep your M22 alive. On launch, less clutch slows your rate of rpm loss when you dump the clutch, so it takes longer for engine rpm to drop far enough to sync up with wheel speed. By delaying the sync’ing of engine rpm and wheel speed (clutch lockup) to a point farther down the track, the car will have had more time to accelerate so it will be traveling faster. Basically, rpm won't dip as low because the car will be traveling faster when things sync up. Same thing happens after the shifts, which means recovery rpm will be better after all the shifts down the track. It all adds up to the engine being able to pack more revolutions of power production into the run. A 500 rpm improvement on after shift recovery is not uncommon with a well matched engine/clutch package. If you simply air up the tires until they spin you will get much the same effect on launch, but there will be little if any spin after the shifts which means engine rpm would get dragged down lower after the gear changes, effectively lowering your average rpm. Adding air also reduces traction which helps your M22 live thru the launch, but since the tires won't likely spin after the shifts, your M22 would then still suffer the full hit from your current clutch. The benefits of lower clamp are not limited to those with adjustable clutches. Fast Coyote Stock guys have it figured out, using non-adjustable diaphragm clutches with great success... Last edited by weedburner; 10-20-2016 at 01:36 PM.