rear end gear ratio

[wakebdr2]

Hey guys whats up. I just purchased some new street slicks for the GN and wanted to put some new gears in the rear end since I put taller tires on. The new tires are only about 3 inchs taller than stock, and was wondering if a 4.10 was a little too tall. Or if a 3.73 would be better. Any feedback would be great. Thanks.

 

[steve davis]

REAR END

THE STOCK REAR END 3.42 DONT CHANGE,DONT EVEN THINK ABOUT IT.THATS ONE THING BUICK GOT RIGHT

 

[RobsIron]

4.10s are to deep. 3.73s at the most. 3.55s would be a happy medium.

Overall I think most would say to keep the 3.42s. These cars seem to perform the best with the stockers no matter the size of tire.
There are some super TR gurus on here that would know better than I, but I'd bet they're gonna say stick with the 42s. HTH.

 

[wakebdr2]

So a 3.42 will be fine? How about the width. How wide is too wide for these things?

 

[steve davis]

REAR END

10" IS MAX

 

[turbo2nr]

I have 10.5" slicks, and 4.10 gears....I like it. I use OD on the track. I tried 3.73 and they seem just like 3.42 to me. Race Jace and many other serious racers use up to a 5.10 rear gear

A 5.10 rear gear using OD, is the exact same gearing as a 3.42 in 3rd gear. Just something to think about.

I havce 3.73 gears for sale, very little use.

 

[microELVIS]

You didnt specify how tall the slicks were that you purchased ?

 

[Ormand]

You didnt specify how tall the slicks were that you purchased

He said in the original post that they were about 3" taller than stock. That is about 10%, so it would seem like the gear could change to 3.73, and be pretty close to the stock set-up, as far as matching. For race only, as turbo2nr points out, something much bigger could be used, with overdrive.

 

[Intercooler]

Originally posted by turbo2nr
I have 10.5" slicks, and 4.10 gears....I like it. I use OD on the track. I tried 3.73 and they seem just like 3.42 to me. Race Jace and many other serious racers use up to a 5.10 rear gear

A 5.10 rear gear using OD, is the exact same gearing as a 3.42 in 3rd gear. Just something to think about.

I havce 3.73 gears for sale, very little use.

Who uses gears that size? Who uses anything over a 3.73 ratio? Never ever heard of anyone running 5.10's.

 

[turbo2nr]

Originally posted by microELVIS
You didnt specify how tall the slicks were that you purchased ?

Are you asking me? I run 28" tall tires.

 

[turbo2nr]

A lot of track cars that are still banging on the 200r4 use 4th gear and big gears. Art Carr tells me of many that are happy and faster that way. Most of these cars use a non-lockup because of big power, and a lock-up 3-4 is a bad idea anyway. So many different combos. I still get good gas milage with 4.10 gears and 28" street tires. To each his own.

 

[Intercooler]

Originally posted by turbo2nr
A lot of track cars that are still banging on the 200r4 use 4th gear and big gears. Art Carr tells me of many that are happy and faster that way. Most of these cars use a non-lockup because of big power, and a lock-up 3-4 is a bad idea anyway. So many different combos. I still get good gas milage with 4.10 gears and 28" street tires. To each his own.

Who uses 5.10's?

 

[re-evaluating]

Who uses 5.10's

Originally posted by turbo2nr
I have 10.5" slicks, and 4.10 gears....I like it. I use OD on the track. I tried 3.73 and they seem just like 3.42 to me. Race Jace and many other serious racers use up to a 5.10 rear gear

A 5.10 rear gear using OD, is the exact same gearing as a 3.42 in 3rd gear. Just something to think about.

I havce 3.73 gears for sale, very little use.

Are you refering to Race Jace Cramer of RJC if you are then you are mistaken. I just sold Jason new gears for his car along with a bunch of other rear parts for his car. I can tell you for sure it was NOT a 5.10 gear NOT even close...

 

[turbo2nr]

I was told by Art Carr that he does use those gears, sorry if I am mistaken, I do not know Jason, but have ordered stuff from him. The info about the 5.10 being the same as a 3.42 in third is accurate. I was told that more than a few TSM guys are trying this.

 

[re-evaluating]

Phil Mcgloin

As far as I know (and I don't know much) Phil Mcgloin MAX PSI is the only one running anything like that.. He does in fact run 5.13 with a 29.5 tall tires on his car. Maybe he will chime in with his thoughts on this but the 3.42 work very well in my opinion.

 

[Intercooler]

Re: Phil Mcgloin

Originally posted by re-evaluating
As far as I know (and I don't know much) Phil Mcgloin MAX PSI is the only one running anything like that.. He does in fact run 5.13 with a 29.5 tall tires on his car. Maybe he will chime in with his thoughts on this but the 3.42 work very well in my opinion.

Is it a Stage 2 turning 8k RPM's or a stock block?

 

[re-evaluating]

Phil Mcgloin

Originally posted by Intercooler
Is it a Stage 2 turning 8k RPM's or a stock block?

Low 10 second (so far) stock block TSM car using all 4 during the run.... Just another way to do it.. I prefer a little different way but it works for him.