How much can a FS5C71A handle?

How mutch can a FS5C71A handle?

 

I will have the engine stroked to 2.7 with ported head, 460 lift cam, tripple weber. I hope for 220 ft lbs. and 170 to 190 WHP.

It will be just street driven but also in the Swiss mountains with a lot of 180° turns and full brake/accelerations.

 

(I'm not a burn out guy but after clutch release a stump on it one.)

 

Does ist hold up?

 

Thanks

Marcel

with my L28et I have blown 1x260z and 1x 280zx box, I currently have a strengthened 260z 2+2 box in it and so far its holding up but you can here the strain, im about to put a gbox from a r32 turbo skyline in mine

Its a FS5W71C

From a R32 Skyline rear wheel drive RB20DET engined car.

 

Same box, but only 50 mm longer at tip end of extension housing, from

Sylvia model S13 or S14 with SR20DET engine.

 

Both the above will require your donor Lseries BType box bell housing to be slightly modified and fitted.

The '71A gearbox can not handle much more than stock power levels and synchronizer assemblies have been harder to find for a while now. It's essentially a modified and strengthened roadster gearbox. I would set it aside for someone who needs it for vintage racing, and go for a later model gearbox from a ZX or a ZX turbo. There are plenty of ZX turbo models out that part of the world, and they'll work well with the rear gears in your Z.

 

He's got an early 3-piece 5 speed, gentlemen, with the 3.90 ratio R180 rear end, gentlemen, it's not a common box in the US, and we don't see many of them here. You all might see more of them in the Southlands; but that's the extent of my knowledge on them.

Yes, I do have the in europe and australia common 3 piece box and I love the gear ratios. 2.9 first. (Cool speed up to 70km/h). The newer are 3.3 or so.

 

Synchron rings and bearings are avail. in Australia. (the whole kit around 800$)

 

What would fail on it and is there a way to make it stronger?

ive had bearings fail both times in mine

The early 3 piece boxes, FS5C71A -Close-Mid-Ultra.

I've got six of them, four are the std close  ratio model ie 2.9 first,

One is a Mid Close model 2.6 first,

And,

one in Ultra Close, with 1.8 first

 

The mid and ultra have done service behind a 245 hp at flywheel engine, in race use, and provided they are treated with care, they handle that power quite nicely. Parts are obtainable, not cheap though!

 

They are for sale!

I have no idea how much power my car must have then, I have not once dropped the clutch and do not shift hard and have shattered 2 of them both with new sincros bearings etc

The early 3 piece boxes, FS5C71A -Close-Mid-Ultra.

I've got six of them, four are the std close  ratio model ie 2.9 first,

One is a Mid Close model 2.6 first,

And,

one in Ultra Close, with 1.8 first

 

The mid and ultra have done service behind a 245 hp at flywheel engine, in race use, and provided they are treated with care, they handle that power quite nicely. Parts are obtainable, not cheap though!

 

They are for sale!

I guess I have the std. (version not checked yet)

Ok thanks. I will try it and see what happens.

Both the above will require your donor Lseries BType box bell housing to be slightly modified and fitted.

Well unless you are lucky enough to get hold of the Lseries C box from a LD28 - you still need to swap the bellhousing for on to the RB20DET or SR20DET box as the LD28 C box is like a normal B box inside aka thin gears etc. But the bellhousing does not need any mods. I have purchased 3 of these boxes over the years for these bellhousing - all from JDM imported Laurels here in NZ.