Best axle ratio..........
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Le Mans Master
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From: Richmond Kentucky
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Best axle ratio..........
What is the best rear axle ratio for a 68 with big block and wide ratio Muncie 4 spd trans? Use is general cruising and occasional highway use. Current gear is 4.11 and it's too low (too high numerically speaking). Am considering replacing the R&P with a 3.55 or 3.36 and will need a ring gear spacer if I go that route. Also, where can I get one of these spacers?
Race Director
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From: NYC NY
I would go with the 3:36s if you are not worried about all out performance. Unless the motor has a high RPM power band the big block torque will pull the car quickly enough to put a smile on your face. The tall rear end gears make highway driving way more comfortable. Besides who wants to drive 55?
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From: CORVETTE 77 385 C.I. TEXAS
Thread Starter
Le Mans Master
Joined: Oct 2007
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From: Richmond Kentucky
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Thanks everyone for your comments.
Does anyone know where I can get a ring gear spacer that will allow me to use the thinner 3.36 ring gear on the 4 series carrier? Also, I have seen somewhere (can't find it now) a calculator for determining theoretical rpm with certain gears and tire sizes. Mine would be 3.36 rear gear and a 27 inch tall tire.
Thanks,
Rex
Does anyone know where I can get a ring gear spacer that will allow me to use the thinner 3.36 ring gear on the 4 series carrier? Also, I have seen somewhere (can't find it now) a calculator for determining theoretical rpm with certain gears and tire sizes. Mine would be 3.36 rear gear and a 27 inch tall tire.
Thanks,
Rex
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Le Mans Master
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From: Fremont CA
If your 4 series carrier was one of the good big window ones and not cracked, I would trade you a 3 series for your 4 series or I will sell the 3 series posi carrier (bare carrier) I have for $220 shipped to any of the 48 states. Email zeohsix2002@yahoo.com Eric B.
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Le Mans Master
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From: Glen Allen, VA
I have ridden in a 66 with a very strong big block, (600 hp strong) and close ratio 4 spd with the 3.36 gear. That car did not need any lower gears, it still took off like a rocket, so I would agree htat with a big block 3.36 gears would be great.
Race Director
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From: central FL, near the beach.
What is the best rear axle ratio for a 68 with big block and wide ratio Muncie 4 spd trans? Use is general cruising and occasional highway use. Current gear is 4.11 and it's too low (too high numerically speaking). Am considering replacing the R&P with a 3.55 or 3.36 and will need a ring gear spacer if I go that route. Also, where can I get one of these spacers?
Start out in 2nd gear for a week. Might need to adjust the idle mixture/speed and rev it a tiny bit more when u 1st pull out. If u like it, well, that is what a 3.08 would be like. If it is a TQ monster u might go 2.73 for low rev cruising. If it lacks low rpm TQ see the article in my sig/profile. Could boost TQ LOTS and allow 3.08 or even 2.73
Last edited by Matt Gruber; Aug 18, 2009 at 03:43 PM.
