RA28 SR20 diff options... Is the Volvo setup strong enough?

[drumerboyben]

Hi all,

I've had a bit of a look on the topics on this already, but I'm looking for a bit more input/opinion from people who actually have the Volvo diff setup in their car.

I've just bought an SR20 half cut to put into my RA28, I've also picked up a Volvo diff which I was planing to put the Eaton TrueTrac LSD into. I've been calling around some of the diff shops here in Melbourne but the ones which are supposed to be top quality (Supa Trik in Dandenong & Geelong Differentials) have advised me against the Volvo option... both saying that they rekon it'll break and that I should go for a Borg Warner.

The car will be a daily driver with maybe a few track days here and there. I'll be looking for somewhere between 160-200kw and defiantly no more than 250kw in the long run.

With all of this said, what are peoples opinion of the Volvo diff setup for this application? Do you think it will hold up? What kinda power are you running through yours?

Any help would be much appreciated....

Cheers,
Ben

[Joshstix]

I don't have the Volvo diff in any of my cars but I just wanted to point out that you need to think about the experience and knowledge that people are working from when they give you answers. Most main stream diff places have NFI what kind of diffs are under old Volvo's for a couple of reasons A) they rarely brake so rarely need to be worked on and B) Who cares what kind of diff an old Volvo has.

The main stream places are knowledgable about the mainstream products 9", Borg Warner etc since that is the majority of their "Hi Performance" work and what the common bogan mobiles run.

[pandaah]

in my opinion, i would be looking at the "members rides" section and lookin under all the RA28's and finding one thats been modified and creating the same power as yours has, see if you like there setup and what they did, and start planning from there....

2 hours reading will save you plenty of time and money.... its all about the research

[86-Sh*tter]

id be going with something like a f series diff with a mx73 grande lsd, food for thought

[stidnam]

I have a ra28 with a 1j running a volvo diff. Nothing much done to the car except an exhaust and cooler.

Like yourself I rang around a couple of diff places and they were all unhelpful saying I should just go borg warner as well.

I liked the volvo setup because of the cheap outlay, they are a chunky diff with decent size axles with a rear disc brake setup and the handbrakes aren't that hard to hook up. Just a little shortening of the cables and rebrazing the ends.

A couple of things to watch for though. There are two LSD centres out there that fit. One is a front jeep diff and the other the rear. You want the rear. I'm pretty sure there are part numbers etc in the volvo diff conversion thread. Have a read through all of that.

The other thing to watch for are the locking collars for the bearings. The diff shop I went through got some aftermarket bearing kits and the locking collars were too tall, meaning the axles wouldn't fit. That was a royal pain in the arse to find out once the diff was in the car.

I can't really comment on track or drags but I've been generally happy with the diff on the street. Another friend had the same diff in his ra23 and it held up to everything he gave it. On the track though I think he had some problems with his inner wheel spinning through heavy turns.

stidnam

[Mundoolun]

I had a RA28 with a stanard diff with a 1975 Corona Mark 11 diff centre. The car had 3inch exhaust pod and intercooler upgrade as well as two fuel pumps. Made only 134.5kws at 10psi. The diff lasted untill the right rear wheel stud came loose and the nuts rattled off and sent me doing two 360s. I survived with only a cut and bruise. Volvos are fine. Hilux has more centre options but is heavier and needs a brake conversion if you wish to run discs. On the street you be fine but onces you get to the drag strip or circuit on stanard diff bang. Drive sensibly.

[river]

Hi,

I heard, but am in the process of trying to verify, that you can get a stronger centre for the existing RA28 diff. I'm making 160rwkW and am running the stock diff without any issues, but then again I don't give it a hard time (ie single wheel spinners or drop the clutch at high revs) and the diff is fine. Of course, for track work and such things I'd be looking at getting an F or G series diff - but for me, a stronger centre would probably do me fine for how I drive.

seeyuzz
river

[drumerboyben]

Thanks everybody, I think I'll stick with the Volvo diff as I'm not planning to do a lot of track work. In addition to what you've said chatting to Stew a bit about it as well as seeing some of Blakes crazy burnouts has been more than enough to convince me that it'll hold up. Now off to order that True Trac =D

[river]

Hi,

Do Tru-Trac make a centre for the T-series diff?

The stock RA28 diff is a 2-pinion diff, which means it is not strong one the single spinner situation. Toyota did make a 4-pinion LSD for the T-series. If you get one of them you have a much more robust diff. If you get one of those and limit dropping the clutch at revs then you'll probably find the diff will last you years.

seeyuzz
river

[Shifty]

r31 skyline. end thread.

[Shifty]

id be going with something like a f series diff with a mx73 grande lsd, food for thought

er... wot?

[drumerboyben]

Hey River,
Check out this link, it's Eatons application guide, if they have something for the T series it should be in there...

[bigmat]

my thoughts. i have 28 with sr20 200rwkw g series with torsen. hooks up just fine dosent skip a beat. ive been in bigworms 23 with volvo diff and it hooked up just fine with no probs. if i did it again i would go volvo as its lighter so your on a good thing

latter mat

[lexsmaz]

My trusty old V8 Volvo i had years ago, had a old style Borg Warner housing & centre grafted to it, again speaking to diff people !!

I wish i was aware of the jeep centre use then as even though the Borg warner was a 4 pinion set up but only a cone style LSD i managed to destroy it in about 6 months ( as in the LSD did not function any more ) ...

Could get quite costly but i was thinking if you put an Air locker setup in the jeep centre in the Volvo diff it would be a very strong setup ..


I have also heard from a diff shop that the Volvo axles are made of some very high quality steel & that it would be very unlikely that they would cause any issues or break ..

[SillyCarS]

i have a g series in my 23 which will make my 200kw+ 1g the weakness in the drivetrain

my 18rg blew my t-series with 110rwkw so stock diff is a joke