anyway to tell if i have 3.73's

[Jrgunn5150]

Are you going to be at the strip looking for that ultimate low ET? Are will the car remain the same as you use it for now?

 

[voidfinger]

the same.. but i'm looking for performance too. ya know. But i guess i'll still be using her as the d.d. for now.

 

[Jrgunn5150]

I would do 4.10's then, 4.30's if you stick with the auto.

 

[voidfinger]

then the rpm would kill with the auto though....they would be higher than the 5 speed.

 

[Jrgunn5150]

Yep, but auto's need more gear than 5 speed to run roughly the same.

 

[voidfinger]

I think i'll stick with the 4.10's. Plus i could go on and put them in on the 2v too.

 

[Mr. OAM]

voidfinger........interesting name BTW.....


It sounds like you need to get an education on this topic. Asking around is great for getting input and a general idea of things, but other people's preferences are often different than your own and only you know best what you are looking for. There are many free calculators online that you can find doing a quick search. That way you can also enter your tire diameter as well as rear gear and your transmission's actual 5th gear ratio and get a better idea of engine RPM at various speeds. You know how you drive and for how long and what you will tolerate in scarifices for performance gains. Find an article online (usually the magazine websites have archived tech articles that have been in their magazines) and learn about all the considerations and other chassis dyno test results of RPM's in relation to gear ratio and tire sizes. Then there is also compensating your speedo.

Steve

 

[voidfinger]

Any calculators that you could recommend. Everyone that people have sent me to have been way wrong... one even told me with what i have now that it should be at 2500rpm with my 3.27 stock gears at 65... when i'm really running 1700/1800

 

[Jrgunn5150]

Are you sure you are entering your correct OD ratio and tire diameter? I think your's is .62

 

[voidfinger]

The one i put in the other day didn't ask for a ratio... they just asked for the trans which i selected the 4r70w and then the 3.27 gears with a 255/40 tire. Wierd number !!! lol , but i don't know what the gear numbers are for these cars... Could you give me the 4r70w numbers again and the numbers for the t/45 ? thanks

 

[Mr. OAM]

That may be the reason for your weird numbers. You need to have your exact gear ratio in 5th and exact tire size, sometimes they want the actual diameter. There are other online calculators for that and they are pretty consistent. Only use online calculators for engine RPM that take into consideration transmission gear ratio, rear gear ratio, and tire diameter, and of course the speed you are curious about. This will give the best calculation of RPM at the front of the mess. Then use several of these calculators to get an average. There will be slight differences in them sometimes. If the difference is more than slight then disregard that result.

Steve

 

[voidfinger]

O ok i got ya. I'm thinking though that i would be better off just sticking with the 4.10's for now. It seems to be a good all around gear with not to many rpms at 65. I'm not going to be going over the speed limit once i do the project. So, hopefully good gas milage won't be that far away. Lol with my 3.27's and auto i went 120 miles on the interstate yesterday and i check since i was going 65 the whole time and i got 33.25 Miles to the gallon. I was like whooo hoooo. LoL

 

[mark8796]

someone may be able to chime in and clarify or correct me, but, if you should need to change your rear end fluids...you can find out your current rear gear ratio by dividing # of teeth on your ring gear by the # of teeth on your pinion gear. example: 41 ring gear teeth and 10 pinion gear teeth makes for 4.10 gears. later.

 

[Downshift]

It will also be stamped on the ring and pinion gears. On the back of them, so if you do need to change the fluids or gasket out than you can just take a peak at it.

 

[danroadking]

someone may be able to chime in and clarify or correct me, but, if you should need to change your rear end fluids...you can find out your current rear gear ratio by dividing # of teeth on your ring gear by the # of teeth on your pinion gear. example: 41 ring gear teeth and 10 pinion gear teeth makes for 4.10 gears. later.

Yes, you're correct