What ratio would you use?
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What ratio would you use?
I have a 79 with a 385 stroker. It has about 500 horses natural and about 600 with the NOS. I have a richmond 6 speed with a 3.27 first gear and a .80 overdrive. My rear tires are 28 inch nitto drag radials. Right now I have a 4.10 rear. When I drag the car I am in 5th going through the traps. The best I have run is a 11.60 at 125mph. That was with a 1.8 60 ft time. I think the car has more in it but I seems I am shifting through gears to fast. It is mainly a street car that I j took it to the track after I put it back together to see where it was at.
I am thinking of putting in a 3.08 or 3.36.
What do you guys think. What would you put in if it was you car?
I am thinking of putting in a 3.08 or 3.36.
What do you guys think. What would you put in if it was you car?
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I would initially say the 3.36's for N/A running. My 427 loved that combo with the Doug Nash 5 speed. That got me a 4.13 final drive and I was using only 26" slicks. I ran the same combo with the 540 for awhile. I have a buddy with a 502 and N20 in a '64 coupe. He sprays it all the way through with his Richmond 6 speed/3.36's only using first 4 gears. He's in the low 130's on trap speed.
3.36's will get you around 130mph @ 6500 rpm.
Is that 125 on the juice? How high can you wind it?
I run 3.07's behind my 540 now...but trans gearing has me even deeper with a 4.40 final in 4th. I use 28" tires now. It likes being run out the back door!
JIM
3.36's will get you around 130mph @ 6500 rpm.
Is that 125 on the juice? How high can you wind it?
I run 3.07's behind my 540 now...but trans gearing has me even deeper with a 4.40 final in 4th. I use 28" tires now. It likes being run out the back door!
JIM
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[QUOTE][/Is that 125 on the juice? How high can you wind it?
QUOTE]
Yes, Its 115 without and 12.3 seconds.
Has your buddy had any problems with the richmond. I've blown up 2nd 6th and the 5th and 6th mainshaft. I need to lose some weight. I'm 3600 with me in it.
At the track I make more ground in fourth and fifth, thats where I make up my time. Most of my 60 fts were 1.8 to 2 seconds. I had a bad wheel hop problem.
It would be nice to hit the traps in fourth. I wind it out to 7000 mabye 7200 in the first two gears.
QUOTE]
Yes, Its 115 without and 12.3 seconds.
Has your buddy had any problems with the richmond. I've blown up 2nd 6th and the 5th and 6th mainshaft. I need to lose some weight. I'm 3600 with me in it.
At the track I make more ground in fourth and fifth, thats where I make up my time. Most of my 60 fts were 1.8 to 2 seconds. I had a bad wheel hop problem.
It would be nice to hit the traps in fourth. I wind it out to 7000 mabye 7200 in the first two gears.
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When I was drag racing with my 383 and 4.11 with Th700R4 and 3500 stall. I was able to get 1.70's 60's with 10X28 slicks with 9 psi and 11.70,s at Sacramento drag strip on 90 degree days for the all corvette drags.
I had to short shift the 1-2 @5000 rpm then just floor it all the way and leave it in 1-1 third through the lights. You have to think how shifting cost time. With 28 inch rear tires you are talking about 140 mph @7500 in Third gear 1-1. So I was never more than 6800 at the lights.
The more power you make the less you would want to shift.
Do the Math and 3.73 or 3.90 might work
I had to short shift the 1-2 @5000 rpm then just floor it all the way and leave it in 1-1 third through the lights. You have to think how shifting cost time. With 28 inch rear tires you are talking about 140 mph @7500 in Third gear 1-1. So I was never more than 6800 at the lights.
The more power you make the less you would want to shift.
Do the Math and 3.73 or 3.90 might work
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The Richmonds aren't super stout. I broke 3rd gear a couple of times, and two buddies have done the same. I'm 3650# with me in mine.
But the guy with the 6 speed ROD has had incredible luck. He pounds it hard, pulls wheelies and is using a clutch that grabs hard with little slip and hasn't broken it yet.
I'm not sure what they did to it exactly, but when he bought it, he shipped it to S&K Speed and they went through it. Whatever they did works great!
They are also the best place to get parts that I know of. Ask for Brian.
http://www.skspeed.com/aboutsk/transshop/
JIM
But the guy with the 6 speed ROD has had incredible luck. He pounds it hard, pulls wheelies and is using a clutch that grabs hard with little slip and hasn't broken it yet.
I'm not sure what they did to it exactly, but when he bought it, he shipped it to S&K Speed and they went through it. Whatever they did works great!
They are also the best place to get parts that I know of. Ask for Brian.
http://www.skspeed.com/aboutsk/transshop/
JIM
