Datsun LSD VS Welded Diff

[Steve49841]

Does anyone have experience running a Datsun LSD in a race car. I'm currently using a welded Diff which is okay on a road course but I don't like it for AutoX.

[Mike Unger]

Yes, I've used all types. What is your question?

Mike

[Steve49841]

Good point, I should have asked a question. Is a Datsun LSD up to the job of handling the loads put on it by a race car or is something else better.

[Mike Unger]

Very much up to it. The H190 LSDs have been used in a wide variety of Nissan race cars (roadsters, 200SX, HL510, 1200 GTL etc.) for many years. They require shimming of the clutches to get the desired break away depending on the car set up and application. I use one in my roadster road race car.

[Steve49841]

Hey Mike, thanks for the info... I have a few more questions. One, Is there anything different about an LSD install VS a non LSD. Two, where would I get the shims you mentioned. And third, do you know where I might track down an LSD unit. Thanks....Steve

[Mike Unger]

They occasionally show up for sale here. You can post a wanted ad. The pumpkin itself is the same and it installs the same in the rear housing. The ring gear carrier is the LSD part. The unit needs to be assembled by someone that knows what they are doing as the pinion height and gear backlash are critical for it to last and must be set up correctly if you are installing the LSD unit in a different rear or changing ratios. They made two sizes of LSD carriers for differing thicknesses of ring gears. I think 4.38, 4.62 and 5.125 were the 4mm wider gear carriers. You can use the thinner ones with a 4mm spacer to install one of those ratios but obviously not visa versa. Make sure you get one that will fit your desired application. A LSD made for the 4.62 won't go into a 3.89 for instance. The clutch shims can be made by cutting them out of sheet shim stock. They look like big flat washers the size of the friction discs. They go on top of the clutch stack before assembly. They set the preload to the clutch.

[Steve49841]

I've located a unit with the ratio I want so changing the ring gear will not be an issue. Setting the preload and actual installation will have to be dealt with however. From reading your reply I need to pay attention to what I'm doing, thanks.

[TexasStig]

On another thread, Steve Heimsoth mentioned swapping in a 8" Ford read axle. I didn't find this swap mentioned anywhere else, so was wondering if anyone else did that as well and what all was involved.

[Alvin]

On another thread, Steve Heimsoth mentioned swapping in a 8" Ford read axle. I didn't find this swap mentioned anywhere else, so was wondering if anyone else did that as well and what all was involved.

go here, scroll down:
http://311s.org/phpBB3/viewtopic.php?f= ... e&start=45" onclick="window.open(this.href);return false;

[spl310]

On another thread, Steve Heimsoth mentioned swapping in a 8" Ford read axle. I didn't find this swap mentioned anywhere else, so was wondering if anyone else did that as well and what all was involved.

go here, scroll down:
http://311s.org/phpBB3/viewtopic.php?f= ... e&start=45" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Mmmm... Sexy...

[Gregs672000]

What a sexy beast that car is in the referring thread. Truly incredible and highly professional work!

[SLOroadster]

On another thread, Steve Heimsoth mentioned swapping in a 8" Ford read axle. I didn't find this swap mentioned anywhere else, so was wondering if anyone else did that as well and what all was involved.

go here, scroll down:
http://311s.org/phpBB3/viewtopic.php?f= ... e&start=45" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Mmmm... Sexy...

Mmmmm HEAVY! My friend Tim had a Ford 8" rear end on one of his race cars, it was far heavier than the stock one. Sure diff internals are easy to source, but the axles are still custom, and yeah its way heavy.

Will

[spl310]

Yes, it is heavier than stock, but that is not going behind a 100hp engine either. I doubt that the driver will EVER destroy that rear end. And it is not as big and stout as the legendary 9"!

[RC240z]

It IS heavy, but if you have the HP to back it up, okay...

Not vintage, and heavy from a racer perspective. Takes the broken axle problem off the table...full floating Toyota units with rear disc brakes are an option too. Bullet proof, rugged and not as heavy....But I digress....

R

[fj20spl311]

For a race car...if the rules allow....I would get a Speedway Quick change
Either a hot rod version:



Or a full floater Mini Stock: