Optimum rear gear for street.

[73chgrSE]

I have plans to get a stroker kit for my 400 and go to 470. The car is a 3 spd auto/slap stick. 8 3/4 727. Will a 4.56 gear make the car too hard to drive on the highway? What about a 4.10? I'ld like to keep the slap/3spd.

[Ghoste]

You're going to get a lot of different answers to this one but at the end of the day, you're the only one who can make that decision.  It has to be based partly on how you plan to use the car and partly on the powerband of your combination.
As a loose opinion, I'd say you'll be happier with a 3:91.  The 4:56 is a pretty serious gear for a street car and with the stroker, you'll have lot's of low end torque which will help to compensate for a higher ratio somewhat.

[John_Kunkel]

Anything numerically higher than a 3.55 will get real tiresome on the highway.

[Steve P.]

Add a Gear Vendor's over drive unit.

[Runner]

depends on where you live.  ive been runiing 4.57s in my raodrunner ror alot of years. i just put 4.10s in the car and i like them much better.  infact it feels just fine for me on the free way but id lived with 4.57s for a long time.

[deputycrawford]

My opinion would be to go no more than a 3:55 gear with that stroker. The average report from the stroker guys is that you will have more torque than you can use most of the time. Many strokers with 3:55's have very good track times and can drive home at 70 M.P.H.  Thats just my 

[phat69charger]

I agree with Ghoste, you will get different answers but you will find it hard to make a decision based on what others say about gears, with out the benefit of trying other ratios out first before you settle on one, that's why I always refer people to this link:  http://users.erols.com/dmapes/GEARCLC.HTM  it allows you to compare what you have already to other combinations and ratios, you know the operating range of your engine so it's perfect for checking out the Speed and RPM's your engine will be operating at, if my engine redlines at 8000 Rpm's and I run 4.56's and someone else's engine redlines at 6000 Rpm, the speed difference at redline is not even close, so that's why I say check it yourself.

You can also save the linked page above and it will work without being online.

[phat69charger]

I also forgot to say that if all of the other factors about different vehicles where equal like weight, transmission, and traction the calculator is a good means to get a ball park figure without going through several rears for test.

And also since the calculator has 8 positions for gears you can punch in different OD ratios in the left over slots to compare Over Drives.

[max]

Anything numerically higher than a 3.55 will get real tiresome on the highway.

i have always had good luck with 3.55's behind a automatic and the rpm isn't to bad on the highway.

[daytonalo]

The rule thumb one need's to keep in mind , the more torque one has never go above 355 if you don't want to get smoked on the highway above 70 mph by some kid in a souped up honda !!!!!!!!!!!!!!!!!!!!!!!!!!!!!