Some questions regarding transmission and diffs. - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

302_supra · 05-29-2003, 04:55

Hi there. I am new to the ford forums...I own a 1983 toyota supra...and unlike all other conversions..it has a Boss 302 in it! It is in the process of transforming now. A home made boss...302 windsor block with 2v closed chamber cleveland heads.
Now for the questions
Does anyone know how many revs a boss 302 should be doing at about 110km/hr...or about 65mph??? The toyota used to do 3000rpm with the supra diff, but i am sure thats way too high for the v8?
What car can i source a 9" diff centre with LSD and to fit in the supra, if i decide to replace it??
Also regarding intake manifolds, which am i better off going with? What are redline/ kilkenny like? Or should i do for a different brand?
Thanks for your help
Blake .

WBT56 · 05-30-2003, 04:59

Find out your diff ratio. Some supra diffs run hilux gears and will fit a hilux LSD hemisphere, and if yours does you can get higher ratio aftermarket diff gears to suit. Don't laugh, the hilux set-up is quite strong, I've rebuilt one out of a supra super sedan running big horsepower. Would be a much cheaper option for you. Aim for about 2150-2250@ 110km/h or thereabouts.

302_supra · 05-30-2003, 19:07

Thanks Wbt56, no joke for me there, ive heard about the hilux LSD conversion...never really took much notice of the similarities in the diffs!! For a late model one how much would i be looking at? and that 2150rpm sounds about what im looking for! I know for a fact the supra diff ratio is at least 3.1 I cant remember exactly...but it was too high for the V8. If i can find a hilux centre like you said i think thats the easiest and cheapest way to go...Which hilux would that diff come off?? Which year model is the most compatible? Decided I am going to keep the supra box...just gotta have it checked and fixed as needed. Will be getting a conversion kit from the rod shop to make it compatible with the 302.
Thanks for the help...anything is appreciated

big1 · 05-31-2003, 04:54

Why do you think that 3000rpm is to high for the V/8?

ebxr8240 · 05-31-2003, 07:12

Quote:

Originally posted by big1
Why do you think that 3000rpm is to high for the V/8?

3.1 to 1 Ratio he's talking about... Remember thats top gear with overdrive box. 3.1 to 1 should be around 1800 rpm.. Depending on tyre dia.. Depends on ratio's in box.. If it's anything like a steel case first gear is quite high geared/ long legged...

302_supra · 05-31-2003, 18:30

the box im going to be using is a 5 speed supra box...tyre diameter is 235mm/60/15