I am contemplating buying a BTO 200R4 setup, but BTO couldn't tell me what the final ratio would be in 1st gear (2.74) w/ 25.7" tall tires and 3.73s in the rear end. Does anyone know this formula or a site that has a calculator?

Thanks in advance.

Try this site, it even has GM part #'s

http://www.tciauto.com/tech_info/speedo_gears.htm

Doah, graemlins/clonk.gif I didn't read your post properly, sorry.
Here is another link, although it maynot have what you want

http://nastyz28.com/2gcog/stegmiller/camcalc.htm

2.74x3.73=10.22 overall 1st gear ratio.The tire diameter doesnt change the gear ratio.Taller or shorter tires will make it seem like it has different ratios.

67 Plum,
I understand it won't change the actual gear ratio but, as you stated it will make it seem like it has a different ratio. That is the number I want to calculate. So with the combo listed in my original post my 3.73s would accelerate like 3.90s, 4.xx??

What trans. do you have now?

Are they re-gearing the 700 at bowtie overdrive? Stock 1st gear is 3.06:1 in that trans...

He is looking at a 2004R not a 700.

I currently have a TH350

10.22 divided by 2.54=4.02rear gear to equal 3.73 with 2004r.2.54 is 1st gear in a 350.I am not sure of a calculation to figure in different tire diameters.

67Plum the 200r4 doesn't have a 2.54 low it has a 2.74 low

Jack,

Chad is saying you'd have to have a 4.02 rear gear with a TH350 to equate to a 3.73 gear with a 200-4r. That comparison is for 1st gear only.

Originally posted by 67 Plum:
He is looking at a 2004R not a 700. I don't know how I missed that... Maybe I should look into a hearing aid, the glasses don't seem to help!! graemlins/clonk.gif

Yeah Dennis the numbers seem to run together when you look at the screen alot.A hearing aid might help though. smile.gif

OK, I see what your point is now. I get it.