Which S10 ratio would you use

[29guy]

I am replacing my rear end with an S10 and have located 2 ratios ( 3.08 and 3.42 ) and am looking for some input

The T is running a carbed Buick V6 and a turbo 350. The rear tires are 295/50/15. I am looking for a ratio that will be fine around town and not overtax the engine on the freeway. If it were you which ratio would you go with.? The T is a project so I have no history with what ratio it was runnind and how it performed.

Thanks,

29guy

 

[benT]

I am replacing my rear end with an S10 and have located 2 ratios ( 3.08 and 3.42 ) and am looking for some input

The T is running a carbed Buick V6 and a turbo 350. The rear tires are 295/50/15. I am looking for a ratio that will be fine around town and not overtax the engine on the freeway. If it were you which ratio would you go with.? The T is a project so I have no history with what ratio it was runnind and how it performed.

Thanks,

29guy

I would go with the 3:42 gear. I have a 3.73 in my '27 but with taller tires. I like the pull it gives and with my tire size (275/60/17) it cruises nice on the highway.

 

[rb61069]

I second the 3.42!

 

[29guy]

Thanks benT and rb61069, I'll go with the 3.42.

 

[T-Odd]

With that rear and those tires the engine's going to have a nice hum at highway speed.

I'm running sbc w/ 350 trans and 285/70/r15 on the rear. Diameter of my tires is just shy of 31".

Your rear tires 295/50/r15 will have your rear tire diameter somewhere close to 26 1/2"

That's about 100 revs/mile more that your tires are covering than mine. At 65 miles per hour or more your engine will be turning a little more RPMs than I do and I even want mine slightly lower.

I'm thinking you might want the 3.08 gears instead IF you're going to stick with that short of a rear tire.

Wonder what gears T Pilot runs in his bucket. He's using some really short tires also.

 

[rb61069]

Most T's see more city than highway driving. T-odd is right about having more RPM's on the highway with that size tire. I chose the 3.42 because of the Buick V-6. The 3.42 will make it move just a little quicker around the city. The 3.08 will be a little better for the highway. It all depends on what YOU like and want! Some say these cars are never finshed, because your WANTS and NEEDS change as the years go by. Both will work. If you dont like one then welds brackets on the other and try it!

 

[29guy]

Good thing for me to remember. Not that big of a deal to swap one out.

 

[gfigms]

I used a ratio calc to determine mine. 60 mph @ 2000 rpm with 31" tires came out to 3.25:1 rear end. When I ordered the rearend, Jerry @ CCR questioned it and when I gave him the specs, he agreed with the 3.25:1.

It is very streetable and nice moving down the highway. My days of racing stop light to stop light are over, yet you can smoke the rears with some effort, but it takes practice! :gum:

 

[ellis8500]

With the tires you mentioned, the 3.08 will give you 25 mph per 1000 rpm and the engine will be turning at 2604 rpm at 65 mph. The 3.42 numbers will be 22.5 and 2891 respectively. Think about upgrading to a 4 speed auto overdrive someday. Lets you cruise at 70 mph at about 2000 rpm or less.