shift points and rev limit

GhettoPop · 02-15-2005, 09:12 AM

whats the best shift point on a stock 5.0 w/ t-5? it seems to do well for me around 5100.......

also, is there a stock rev limiter? meaning, if i let my friend take it for a ride, can he over rev it? what can the stock engine handle as far as high revs w/o damage?

Jeff Chambers · 02-15-2005, 11:00 AM

Stock rev limiter is set at 6250. The computer begins shutting the fuel pump on/off to drop fuel; not like MSD boxes that actually drop the spark. The rev limiter won't help at all for preventing mechanical over-rev; meaning that if he shifts from 4th to 1st at 90mph the engine's gonna spin to whatever RPM is necessary to match the mechanical gearing. Been there, done that, bent every valve and pushrod in the motor. The computer's rev limiter will help cut the engine off if he misses a shift and over-revs it between gears.

In terms of the best shift point, with your mods you'll just have to determine the best shift point through trial and error. I'm guessing that it'll be somewhere between 5400 and 5800. I've got a discussion on how to mathematically determine the optimum shift points based on dyno data on my website at http://crt-performance.com/shift_points.htm.

GhettoPop · 02-15-2005, 11:24 AM

damn jeff, your too professional!!! thanks for the help. i was just curious as what would happen if the my buddy upshifted at like 6200, since i never get it up that high. i think u answered the ques, which is that the engine should cut above 6250 anyway, so i should not worry?

Ackbar00 · 02-15-2005, 01:38 PM

nah, not unless you are boosted. It is not good for the engine, but it will be OK to tap it now and then.

I was shifting at 5200 with about your mods. When I got heads and a intake, with stock cam still, I was shifting at 5600.

02-15-2005, 09:12 AM	#1
GhettoPop Gimme a Drink! Join Date: Dec 2002 Location: NYC Posts: 694	shift points and rev limit whats the best shift point on a stock 5.0 w/ t-5? it seems to do well for me around 5100....... also, is there a stock rev limiter? meaning, if i let my friend take it for a ride, can he over rev it? what can the stock engine handle as far as high revs w/o damage? __________________ 1990 GT,stock T-5,K&N w/o air silencer,March underdrives,FMS wires,timing@14*,PA Perf 130amp alt,Steeda Tri-Ax Shifter,Steeda adj quadrant/clutch cable/firewall adj,Centerforce II clutch,o/r x-pipe,Magnaflow SS catback,g-load brace, subframes,Bilstein struts/shocks,Autometer gauges, 136k and running strong!

02-15-2005, 11:00 AM	#2
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	Re: shift points and rev limit Stock rev limiter is set at 6250. The computer begins shutting the fuel pump on/off to drop fuel; not like MSD boxes that actually drop the spark. The rev limiter won't help at all for preventing mechanical over-rev; meaning that if he shifts from 4th to 1st at 90mph the engine's gonna spin to whatever RPM is necessary to match the mechanical gearing. Been there, done that, bent every valve and pushrod in the motor. The computer's rev limiter will help cut the engine off if he misses a shift and over-revs it between gears. In terms of the best shift point, with your mods you'll just have to determine the best shift point through trial and error. I'm guessing that it'll be somewhere between 5400 and 5800. I've got a discussion on how to mathematically determine the optimum shift points based on dyno data on my website at http://crt-performance.com/shift_points.htm. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

02-15-2005, 11:24 AM	#3
GhettoPop Gimme a Drink! Join Date: Dec 2002 Location: NYC Posts: 694	Re: shift points and rev limit damn jeff, your too professional!!! thanks for the help. i was just curious as what would happen if the my buddy upshifted at like 6200, since i never get it up that high. i think u answered the ques, which is that the engine should cut above 6250 anyway, so i should not worry? __________________ 1990 GT,stock T-5,K&N w/o air silencer,March underdrives,FMS wires,timing@14*,PA Perf 130amp alt,Steeda Tri-Ax Shifter,Steeda adj quadrant/clutch cable/firewall adj,Centerforce II clutch,o/r x-pipe,Magnaflow SS catback,g-load brace, subframes,Bilstein struts/shocks,Autometer gauges, 136k and running strong!

02-15-2005, 01:38 PM	#4
Ackbar00 Rebel Fleet Commander Join Date: Oct 2001 Location: Huber Heights, OH Posts: 1,003	Re: shift points and rev limit nah, not unless you are boosted. It is not good for the engine, but it will be OK to tap it now and then. I was shifting at 5200 with about your mods. When I got heads and a intake, with stock cam still, I was shifting at 5600. __________________ 1993 Mustang GT, PTK w/ T-64 - My Cardomain Webpage 11.25@123.5 on only 8 psi. 10.84@121 on only 1 headgasket "The Truth is, Your the Weak, and I am the Tyranny of Evil Men!"