gavan
Well-Known Member
- Joined
- Jul 12, 2005
- Location
- Houston, TX
Should your brakes stall your engine in low/low with the clutch engaged in a manual tranny vehicle?
The braking system is the stock pedal (long throw) to 1 inch wilwood masters to front standard GM calipers/rotors and rear metric GM calipers/K1500 rotors
My Heep has a healthy 4.0 to a t19/stock d300/D44's with 4.88's. Final reduction ~80:1
Preliminary testing shows good pedal feel at street speeds. Stiff, but very acceptable for manual brakes, and easy to lock up all four wheels.
Low/low just bogs down the engine till the EFI decides it needs to bump up the idle a little bit (4.0's are great for that - mixed blessing) then it drives right through the brakes.
Of course, popping the clutch eliminates that problem.
Am I expecting the brakes to do too much? I know over running the brakes is relatively common on auto's, but I had not heard of the problem with manual trannys.
Are the brakes sized wrong? All of my looking and numbers massaging show a chevy caliper and a one inch master with no assist works out to about a 7.5:1 pedal ratio, which is about what the CJ has. Would stepping down to 7/8's or 3/4 inch bore help? Single piston Chevy calipers need alot of fluid, and I would be worried about running out of stroke with a 3/4's master.
For safety reasons , I would like the brakes to kill the motor in low/low, but I guess the bottom line is, even at red line, you are only going 6.5 MPH. Even if the clutch fails, you can yank it out of gear relatively easily.
The braking system is the stock pedal (long throw) to 1 inch wilwood masters to front standard GM calipers/rotors and rear metric GM calipers/K1500 rotors
My Heep has a healthy 4.0 to a t19/stock d300/D44's with 4.88's. Final reduction ~80:1
Preliminary testing shows good pedal feel at street speeds. Stiff, but very acceptable for manual brakes, and easy to lock up all four wheels.
Low/low just bogs down the engine till the EFI decides it needs to bump up the idle a little bit (4.0's are great for that - mixed blessing) then it drives right through the brakes.
Of course, popping the clutch eliminates that problem.
Am I expecting the brakes to do too much? I know over running the brakes is relatively common on auto's, but I had not heard of the problem with manual trannys.
Are the brakes sized wrong? All of my looking and numbers massaging show a chevy caliper and a one inch master with no assist works out to about a 7.5:1 pedal ratio, which is about what the CJ has. Would stepping down to 7/8's or 3/4 inch bore help? Single piston Chevy calipers need alot of fluid, and I would be worried about running out of stroke with a 3/4's master.
For safety reasons , I would like the brakes to kill the motor in low/low, but I guess the bottom line is, even at red line, you are only going 6.5 MPH. Even if the clutch fails, you can yank it out of gear relatively easily.