At what BHP will an E30 diff say "Enough"?

[E30BeemerLad]

My head is spinning with ideas about a mad project of putting the 7M engine from a mk3 Supra Turbo into my/an E30.

Probably wouldn't be until late summer next year before I could do anything as will need workshop and more tools than I have, so will be when living back in Norfolk next year and can use my old man's lock up and my bro's knowledge, he has a MK3 Supra and he's just reconed the the engine & box himself and he works for Lotus Engineering

That engine is 230bhp and a bit more torque out of the box, now it would be rude to leave it standard, so 300bhp seems more in order. Am I gonna be wasting my time with an E30 slipper? What are the options? Possibly retain the Supra diff?

Hmmmmmm?

[fuzzy]

ive got a 3.91 lsd on my cosworth converted e30 touring and it handles it fine , and thats stage 3, 330-340 bhp ,although i do have a spare 3.64 lsd just in case!! mind you i also used a supra lsd when i done a cosworth conversion on my 1985 toyota celica, so either will get the job done! good luck

[glenn]

At what BHP will an E30 diff say "Enough"?

watch this space, i'll let you know

[M3Compact]

It's torque as opposed to BHP that hurts diffs.

These diffs are as strong as fcuk.

Imo the one weakness they have is that despite weighing 38KGs, they don't have a big enough casing to house more oil and dissipate heat as efficiently as they could. 'Endurance' racers use an oil cooler.

7M engine from a mk3 Supra

Diff'l breeze it imo.

Edit...

At what BHP will an E30 diff say "Enough"?

watch this space, i'll let you know

Taking liberties is a different matter.

Good luck.

[stevo]

ive not got the answer but im interested in the conversion, my mates got a mk3 supra and i love it, my 2 fave cars rolled into 1!!! keep us posted

[glenn]

glenn wrote:
Quote:
At what BHP will an E30 diff say "Enough"?

watch this space, i'll let you know

Taking liberties is a different matter.

Good luck.

that made me giggle simon,
i suppose my 'relief valve' will be the tyres loosing traction!
but up to what speed they will lose traction, god only knows.
we will wait and see

[E30BeemerLad]

thanks for the info guys, like I said, this is early days as far as this possible project is concerned. I'm gonna get the tape measure out and measure up under the bonnet. Will get my brother to take some measurements on his supra to see if the lump will fit without much hassle. I suppose it is more a case of the hundreds of components that will need modification that is half the hassle.

Sounds like the e30 diff will be upto the job, supra diff has LSD as standard and they are tough units, ditto for gearbox.

[M3Compact]

i suppose my 'relief valve' will be the tyres loosing traction!

Yep, you might crash it before you break it.

but up to what speed they will lose traction, god only knows.
we will wait and see

Plenty MPH is my guess.

I don't know what gearbox options you've got if any, and sorry if you understand this already Glenn.

The higher geared/lower numbered diffs are stronger, due to the pinion size becoming rather small on anything lower geared than 3.9.

It becomes a balancing act, I'm using a 4.45 with a 6 speed box, which means I don't use first gear, so the actual gears in the box that I'm using are larger/stronger, but my diff is the potential weak link.

If I use a 3.9, I'll be using first to fifth, so the diff would be stronger, but first gear would be the most vulnerable.

There's no 'free lunch', if you can use a higher geared diff (likely with your torque), it'll be stronger.

[320Touring]

given that the e34 and e30 share diffs, then i think that they'd be reliable for at least 535 power, circa 220 BHP

[E30BeemerLad]

this is what will be going in. Think it will be easier to retain the supra box

now where's that tape measure?

[Karan]

the CWP setups in BMW diffs seem pretty chunky compared to other car diffs i have seen (limited)

i feel the tyres would just give way to be honest

i think the UJ just before the prop could be a weak point... not to mention the shell itself.... as apparently e30 shells have been known to get stress cracks......

mine should have 315bhp, and lots of torque, but another car i have seen recently with the same conversion has not had any diff probs....

[ouch]

there was a green e30 turbo in performance bmw , 715bhp i think dont quote me on this , but i think its top speed was around the 200mph mark , so for a bmw diff to be alble to handle the toyota engine, i would think it could.

[E30BeemerLad]

thanks for the input guys, i think i will be sticking with original rear end by the sounds of it

Just got to get some measurements sorted to see if it will physically fit, something makes me think it will be too tall unless leaned over like the m20 is, but the supra doesn't exactly have a lot of height at the front end

Kind of seems wierd I took this picture back in July before I even thought of this, well it was my brother's idea
this is my brother's ebay smoker he is sorting out, mechanically A1 now, just needs tidying up

[ouch]

wooooooooooo another e30 owner with a supra aswell

[ouch]

what will you be doing with the rest of the car once the engines out fella

[E30BeemerLad]

well my brother reckons you can pick up a shitter on ebay for about Ԛ£300, i'll pillage what I want from it and let my brother take what he wants for his and then throw away what's left or ebay some of it.

[dazleeds]

dude get ya bro,s supra it floats

[ouch]

get a sh..er to do that . then if you mess it up u can sell the other one to put your e30 right i cant wait tell my supra is finished

[ouch]

i picked mine up for 250 so you sould be alble to get one cheep

[E30BeemerLad]

here's the sort of candicate for a donor vehicle

http://cgi.ebay.co.uk/1990-TOYOTA-SUPRA ... dZViewItem

[ouch]

looks good ide like to see it when its done

[E30BeemerLad]

does anyone know the weight of a fully dressed M20? and am i right to say the BMW gearbox has the selector coming straight out of the top of the box immediately underneath the gear stick in the car? Hoping Supra one is located pretty close by

[ouch]

not sure about that but what so you think of this supra

[E30BeemerLad]

yep, looks just like this fella, prefer this one, looks a bit smoother

[ouch]

its the same one looks nice though , thats what i want mine to look like in the end but with a twin turbo

[E30BeemerLad]

I had to look twice to start with but they are different cars fella

My brother rates the 2.5 twin turbo they did in the mk3 shape, grey import only of course, aparently they are quite a lively performer, perhaps it is the same lump that's in the 2.5TT Soarer?

[ouch]

I had to look twice to start with but they are different cars fella

My brother rates the 2.5 twin turbo they did in the mk3 shape, grey import only of course, aparently they are quite a lively performer, perhaps it is the same lump that's in the 2.5TT Soarer?

cool , mine is the twin turbo and it is the same lump as in the soarer , i had the 4L v8 soarer now thats a big engine , try getting someone to work on it

[E30BeemerLad]

are you a member of www.supraforums.com ?

[ouch]

no never herd of it but i will be