Best diff set-up for turbo 1st gen RX7??

[Reggie]

I've got a S1 rx7 with a S5 turbo motor, aiming for 300 rwhp. What is the best style diff to use for this set-up??
What is the best value for money?

I've got a S3 diff, and have been quoted ~$1700 for a complete GURU LSD 4.3:1 diff centre (ready to bolt in). Anyone who has experience with or thoughts on Hilux diffs, Mazda van diffs, 9", along with total costs would be greatly appreciated

Thanks

[THRSTY]

if u want a BW (nice, but costly. also, ratios lower than 4.11's are exxy! by lower ratio, i mean numerically higher), speak to bosnjak engineering. have only HEARD good things about them. notice "heard" as ive had nothing done by them personally. have spoken to the guy and was very helpful!!! hmmm, with all the goodies, your looking at about $3-3500

hilux/hiace, not too bad. cheap, can handle some power, centres plentiful (although many wreckers in sydney charge a bit for them. heard that melbourne sell them a fair bit cheaper...so if u know any1 in melbourne???) 30 spline axles, PLENTY of info on net if u want it (cant remember what site, but theres one good one about possible ratios range up to 7.xx:1 or similar, etc), 4pinion centres after circa 1990 much stronger than the previous 2-pinion centres, plenty of parts eg axles, centres etc wont consume too much power, need to change stud pattern. depending on centre, can cost $1-1500

9", can take the most power, upgradable, plenty of aftermarket companies and products, physically bigger than the rest, consumes the most power, need to change stud pattern, plenty of places who do them (sydney comp warehouse do them fairly cheap. dont do installations though, only do 9" to suit, then u put it together) depending on what u want, can cost b/w (but definitely not limited to) $1-3000

not sure about mazda diffs. dont think theyre as strong as the hilux units (smaller axles), but have the same stud pattern as s3 rx7 (?). id assume a similar price to hilux in terms of cutting it down

seriously though, after saying this, i havent done many diff conversions and so havent had the pleasure of trying all of the above options. i have got this info from sources such as other people (whether they be other pf members, or diff business owners), the net, etc.

any1 who feels i should be corrected, plz do so

[mys38u]

the BEST is definitelty a Borg warner diff, but as thrsty said, around 3-3500 for it set up properly, ive heard they are great if u spend the money but not good if u do a straight bolt in.

a S3 diff is much bigger with larger axles (thna s1/s2) and the hilux is a little bigger again. ive had a 3.9 s3 lsd in mine with around 280rwhp and it hasnt complained. i dont do many burnouts, but a lot of launches and HEAPS of hard drivin through twisty stuff.

either of these options will make the car handle still, if u go 9in, around 2200, ul really compromise ur handling.

if u have the money go for a borg warner, if not its a toss up b/w s3 and hilux, ive got a 4.44 centre for $750 pm, if ur interested :)

[BigJ]

I have just put a hilux diff into my series 1. If you find the correct width diff, all you will have to do is redrill the axles and cut the old brackets off the mazda diff and weld onto the hilux. You wont have to cut anything down if you get the right one.

Cheers
BigJ

[Reggie]

Hey all,

Thanks for the info!! Much appreciated.

Hey MYS38U, is that the same diff centre you were advertising a few months ago, with a buggered bearing?

I can give you $500 cash for it this Saturday, if you were interested??

Cheers

[mys38u]

yeah thats the one reggie :) i payed $600 for it, i dont need it and want to get rid of it, so i guess im open to offers, and i pm'd u so let me know :) itl go in the trado next week along with all the other odd and ends i got lyin around, but if you save me a add in the trado ;)

[Shifty]

A friend has a BW diff - from memory ex- VP V8 Commodore. Don't quote me, but from memory it was quite cheap - although beyond the basic conversion I dont' know what's been done with regard to axles, etc. I know he's running 4.11's and the LSD....