Sunny GTi-R Gearbox

Concerning this engine swap business, would the standard SR20DE gearbox be able to handle the power from a SR20DET?

The reason why i ask is, that i was in my local performance garage today, and there was a Sunny GTi-R having a clutch fitted. The guy said he had to remove the drive shafts to the front wheel and the read diff to remove the gearbox. I asked him wether or not i could use a 4x4 gearbox on my FWD Primera but leave the rear drive shaft off. He said that with the coupling being left free, the transfer of power may go to "that" and the front wouldnt drive properly, but he did suggest removing "that" part of the gearbox, which gears to the rear and blank it off with a thick plate. Would this work???? If it does, it would give me a more reliable tranmission for when increasing BHP at later stages:D

note: "that" being the part of a 4x4 gearbox i cant remember. can anyone help?? it may jog my memory.

Originally posted by P11GT
Concerning this engine swap business, would the standard SR20DE gearbox be able to handle the power from a SR20DET?

The reason why i ask is, that i was in my local performance garage today, and there was a Sunny GTi-R having a clutch fitted. The guy said he had to remove the drive shafts to the front wheel and the read diff to remove the gearbox. I asked him wether or not i could use a 4x4 gearbox on my FWD Primera but leave the rear drive shaft off. He said that with the coupling being left free, the transfer of power may go to "that" and the front wouldnt drive properly, but he did suggest removing "that" part of the gearbox, which gears to the rear and blank it off with a thick plate. Would this work???? If it does, it would give me a more reliable tranmission for when increasing BHP at later stages:D

note: "that" being the part of a 4x4 gearbox i cant remember. can anyone help?? it may jog my memory.

Oh my. Where to start? :)

The gearbox on our cars will handle an SR20DET OK. When you start adding more power than a DET, things start to get dicey. A lot depends upon how hard you are on the drivetrain. Most of the folks here with 300bhp or more get their input shaft and all the gears shot peened and cryo treated. It helps.

As for using a GTi-R gearbox with a FWD car?

Forget it. Beside the torque split F/R, the part of the gearbox the propshaft comes off of will get in the way of your exhaust and will also preclude installing the centre brace.

my intention is to buy the whole car, so i'll have both engines and gearboxes, so theres nothing i can do with the DET box, what about making some sort of hybrid? swapping internals? would that work?
Its just that what youve recommended me to do isnt something i could do here, i wouldnt know where to start to look for a company that does that sort of process. Ultimately, i would like to go beyond the standard DET BHP, so i would prefer to do something wiht the gerabox now, rather than later when ive chewed up the gears.

Originally posted by P11GT
my intention is to buy the whole car, so i'll have both engines and gearboxes, so theres nothing i can do with the DET box, what about making some sort of hybrid? swapping internals? would that work?
Its just that what youve recommended me to do isnt something i could do here, i wouldnt know where to start to look for a company that does that sort of process. Ultimately, i would like to go beyond the standard DET BHP, so i would prefer to do something wiht the gerabox now, rather than later when ive chewed up the gears.

I don't think there is anything you can do with the GTi-R box. I'm 99% sure JWT has explored that thoroughly. In fact, they've explored a lot more than that. I helped deliver a SR16VE gearbox. I can't remember the spec, but it was the highly sought after one. This may be promising.

Mike Kojima was trying to convince Quiafe to manufacture a set of gears for the box and came close, but they didn't go for it. Mike even arranged for a 50% down payment (deposit)!

As for finding people to do the shot peening and cryo treating....

YOU LIVE IN THE MOTORSPORTS CAPITAL OF THE WORLD!! :D

I guarantee you that with a little effort you could find someone to do that. Most moderate and larger cities have places that can supply this service. It's used for much more than cars.

Where's Mike from?? Motivational??

I didnt realise that you'd class the UK as the 'Motorsports Capital' cos there aint much of it going on up North. Anyway, i'll ask about, so its Shot peened and cryo tested is what i need?
I take it that shot peening is something to do with hardening?? dont laugh, im not that technically minded! Give me a head Unit, and i'll install it anywhere in your car wether be it in the engine bay! but when it come to the likes of this stuff, i get a bit lost.
So strip the box, and get anything that moves shot peened?

Originally posted by P11GT
Where's Mike from?? Motivational??


No. Mike Kojima is an engineer for Nissan. He also does a lot of freelance consulting. Mostly with JWT now, but also with a few others. He does a great deal of R&D work. He is personally responsible for at least 50% of the SR20 aftermarket in The States. He also is a major contributor to Sport Compact Car magazine.

Originally posted by P11GT
I didnt realise that you'd class the UK as the 'Motorsports Capital' cos there aint much of it going on up North.

Oh, I'm not the one who proclaims it so. The motoring press does. Seven of the eleven teams that make up the FIA World Championship known as Formula 1. The vast majority of the world's race car manufacturers are located in Great Britain. The vast majority of the world's component manufacturers are located there as well. All of the CART Champ Car manufactuerers are located there. Cosworth Engineering is. So is Ilmor Engineering. I could go on and on and on and on and...... :D

Trust me. Great Britain is the capital. No question what so ever.

Originally posted by P11GT
Anyway, i'll ask about, so its Shot peened and cryo tested is what i need?

Cryo treated, not tested.. Ask at the garage you usually go to. I'm sure they will know of someplace. If not, I have little doubt I could find one from here.

Originally posted by P11GT
I take it that shot peening is something to do with hardening?? dont laugh, im not that technically minded!
<snip>
So strip the box, and get anything that moves shot peened?

I won't laugh. Both cryo and shot peening strengthen the parts. It tightens and aligns the the grains. Both, when done properly, should add 20-30% greater strength.

If you would like more info, there is some excellent info from Mike Kojima and Rob Cadle in the SE-R Mailing List archives.

I'd give you more info, but that's the basics of what I know and I don't know the technical aspects as well as Mike, Rob, and a few materials experts on the SE-R list.

Thanks man, i'll have a read thru SE-R later but i'll get onto the garage tomorow and ask about the processes. I'll keep you posted

Going back to the thing about using a DET 4x4 gearbox, it was by removing the transfer box to the rear axle, and replacing it with a blanking plate, thats the idea that has been put to me. What d'you think? can it be that simple???