3.73's or 4.11's again?
#11
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Originally Posted by Colby 04
good point...but I had always "heard" that ratios like 4.11 caused the truck to fall off in 3rd gear. I think V8(Kevin) posted one time about going from 3.42's to 3.73's to 4.10's and he had the same mph, just got there faster with the 4.10's. That sort of backs up that 4.11's are good for takeoff, but lag in 3rd - doesn't it?
The people who are complaining about this phenomenon are probably running 1/4 miles, and nearing the top of the RPM range when they run the traps. They might also be undercammed if their cam is running out of steam near redline.
Rear end gears will not affect how a motor feels a 6,000 RPM, but will certainly change at what point in the RPM range they cross the 1/4 mile point. So, if they are crossing the traps at 5700 RPM with 3.73's, but crossing at 6100 RPM with 4.10's (and they don't have a cam that supports power that high in the RPM range), they will experience a 'falling off.'
Hope that helps.
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Originally Posted by Colby 04
good point...but I had always "heard" that ratios like 4.11 caused the truck to fall off in 3rd gear. I think V8(Kevin) posted one time about going from 3.42's to 3.73's to 4.10's and he had the same mph, just got there faster with the 4.10's. That sort of backs up that 4.11's are good for takeoff, but lag in 3rd - doesn't it?
The 4:11 is great for a trans with a lockup converter and an overdrive. The 3:37 is good for a 3 speed non overdrive (it is a comprimise so you can drive over 65 without winding the crap out of your motor.
In summary the 4:11 will give you the best start in any gear but you will top out faster in that gear and shift to the next gear. In the quarter with my 3:73 I only shifted one time and trapped out at 6000 RPM's. I am waiting to see what the 4:11's do I know I will have to shift 3 times but I will have to see if it helps or hurts.
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I would stick with the 4.11's, these bricks need the off the line help.... plus how really can the difference be in rpm?? ex: my 4.11 @ 70mph is @ 2200, my 3.42 @ 70mph was 1750, so what would the 3.73 be ? 1950rpm?? 250rpm more is not going to hurt you plus it gives you alot of advantages at the track...
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Well I have 4.10's and I want 3.73's, It is so f-ing hard to find tall enough tires with 4.10's
Colby, what RPM do you want to end the 1/4 mile in? or better yet, play with this. http://www.speedworldmotorplex.com/calc.htm
Colby, what RPM do you want to end the 1/4 mile in? or better yet, play with this. http://www.speedworldmotorplex.com/calc.htm
#16
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Originally Posted by Wilde Racing
Well I have 4.10's and I want 3.73's, It is so f-ing hard to find tall enough tires with 4.10's
Colby, what RPM do you want to end the 1/4 mile in? or better yet, play with this. http://www.speedworldmotorplex.com/calc.htm
Colby, what RPM do you want to end the 1/4 mile in? or better yet, play with this. http://www.speedworldmotorplex.com/calc.htm
According to that site I was trapping ~4800RPM with my 4.11's and 28.9" tires. If I was able to acheive the same RPM with 3.73's(which I won't) it would result in a ~107mph trap speed. If I was able to at least trap 100mph, I would be pushing about 4300RPM. Interesting...
I'm glad I'm not the only one considering gearing down...
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Originally Posted by Colby 04
According to that site I was trapping ~4800RPM with my 4.11's and 28.9" tires. If I was able to acheive the same RPM with 3.73's(which I won't) it would result in a ~107mph trap speed. If I was able to at least trap 100mph, I would be pushing about 4300RPM. Interesting...
I'm glad I'm not the only one considering gearing down...
I'm glad I'm not the only one considering gearing down...
need to recognize that "wild racing" has a turbo which according to alot of people with "FORCED IND." works alot better with a smaller gear < 4.10.... if staying N/A a 4.10 is the best option... IMO....
by the way crossing the traps @ 4800 aint good enough.... the higher the better somewher in between 5500-6000.... IMO....
by the way I just got home and im drunk so if Im saying something stupid, ignore me...
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ap2002 is right, IMHO the ideal rpm is 5500-6200 rpm through the traps, how about 4.10 and 26" tall tires. I bet you'd set a new best....
Are you thinking about the gear swap just for racing? Do you plan on doing more to the truck? what is your limiter set at?
Are you thinking about the gear swap just for racing? Do you plan on doing more to the truck? what is your limiter set at?
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Originally Posted by Wilde Racing
ap2002 is right, IMHO the ideal rpm is 5500-6200 rpm through the traps, how about 4.10 and 26" tall tires. I bet you'd set a new best....
Are you thinking about the gear swap just for racing? Do you plan on doing more to the truck? what is your limiter set at?
Are you thinking about the gear swap just for racing? Do you plan on doing more to the truck? what is your limiter set at?
damn I guess I think better when Im drunk... by the way no hangover either!!
yes the 4.10's with a 26"tire is ideal for the track, but the problem is getting it to hook!!!! thats the problem I have and v8 also, I just bought some 28's so and v8 and I are going to try them to see if that helps...
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