Gearing??

[mgbrv8]

I was wondering what gearing you guys run. I imagine we don't need to run much since the cars weigh nothing. And to Low a gear ratio would cause excessive wheelspin with the extra torque and horsepower of  a V8. Also I was thinking about using a Six speed transmission t56 that i have but also i also have a T5. The engine I have is a ls1.  How many of you have six speed transmission's out there and what do you think of them. Mainly what ratios do you all have and what tranny and what I'd your engine speed at 70?  I'm try to figure out which tranny to use I know there will be a bit of fitting with t56 I'm not worried about that.

Dave

[ex-tyke]

Here's a handy road speed/eng rpm calculator for a 5 spd xsmn. Plug in your tire size and your T5 ratios and play around with rear axle ratio to get something that suits your driving style
.
http://www.britishv8.org/Articles/chart.xls

FWIW, I have about a 24" dia tire and a 3.27 RA ratio which gives me 2180rpm at 70mph.

[Bill Young]

You'll be fine with the T5 and it will fit the car a lot better, that T56 is huge by comparison and not really needed.

[classic conversions]

What is your cam cruising rpm, minimum rpm. Then get correct gearing.

[302GT]

I have a 302 with a T5 and 3.43 gearing; at 70 mph it turns at 2000 RPM. In many T-5 transmissions, 5th is strictly an overdrive (mine has a ,61 or so ratio). This is similar to 6th on many 6-speeds. The difference is that a 6 speed has a gear in-between which is handy for high speed racing. My car hits the rev limiter at about 120 mph in 4th, and on a road course there is no point in going to 5th because the gap really slows acceleration. Other than that, i have no use for a 6-speed. With an LS-1, you have more power and torque, so the 5th speed gap becomes even less important.  My cam is good from about 1800 RPM to 6000 (power peak is at 5800 RPM). But the engine pulls well in 5th from about 1400 RPM.

[roverman]

First = 3.818,2nd=2.2,3rd=1.516,4th=1.216,5th=1.024 and 6th =.841(final in od=2.8964) or 3.444 basic. Unit is Porsche Boxter S and appears to be performance gearing to obtain maximum speed potential, at max power band. Time will tell. Good luck, roverman.

[74ls1tr6]

Here is some LS1/T56 info for Camaro's, Firebird's + LT1/T56 gearing ratios. Also using diff gearing ratios together with Trans gearing for MPH.

Link:
http://www.camaros.net/forums/showthread.php?t=98387