Change ring & pinion in 85 Nissan 720 2wd 5 speed???

[handsome_man_777]

Hello everyone! I will start of my apologizing for my lack of experience with this truck, I'm entirely unfamiliar with them. Secondly, I'd like to thank you for any and all help that I can get.

 

I bought a 85 Nissan dirt track race truck from a buddy, have been racing it for the last month and a half. There are a few things I'm looking to do to it in order to get a little more power out of it.

 

As of right now, its stripped down and has the z24 motor, Weber 38 carb, 3.83 rear end and some suspension work. I'm on the hunt for a L20 head to swap over (according some forums I've read, that will have a huge impact) and changing the ring and pinion from stock to 4:10...

 

My problem is, I can't find any where that sells them. Any ideas of where to look? What to look for? The right way to do this? Lol

 

I appreciate all the help. I'm at a loss, and not sure where to turn.

[datzenmike]

Datsuns use an H-190 differential and it's not totally necessary to take it apart and swap the R&P. The differential unbolts and with the axles pulled out can be changed as a unit.

 

 

The 520 Datsun truck with the J13 had 4.875.

The 521 with L6 engine was 4.375.

Most 620 have a 4.375 differential. Early automatic 620s had a 4.625. The '79 620 manual used a 4.11 and so did the '80 2wd 720.

The '81-'82 automatic 2wd 720 had a 4.11.

 

Place an ad in our classifieds... http://community.ratsun.net/classifieds/category/5-drivetrain/?sort_key=date_added&sort_order=desc

 

An L head on a Z24 will require an L timing cover being lengthened 2cm taller and timing chain lengthened. If used with the Z24 transmission the intake with carb and exhaust will be hard over to the left about 20 degrees and maybe into the driver's side inner fender and steering column. Usually this swap is done by using an L transmission and mounting the engine in the L position leaning to the right. This gives room for the manifolds on the left.

[Stoffregen Motorsports]

If you're racing, it's not a bad idea to have a spare complete differential. Buy one from a wrecking yard (or fellow Datsun owner) with the ratio you want. I assume you're using some sort of locker or spool though, right? If yes, then you'll need to have that for the spare diff too.

 

If you want to replace the R&P, try Randy's or West Coast Differentials or these guys - http://www.4x4parts.com/search.html?q=h190&go=Go

 

If you are allowed to change rear axle assemblies, I would swap in a Toyota rear axle. Gears and other parts like lockers are way cheaper for Toyotas. The Datsun gears are not cheap.

[handsome_man_777]

Datsuns use an H-190 differential and it's not totally necessary to take it apart and swap the R&P. The differential unbolts and with the axles pulled out can be changed as a unit.

 

 

The 520 Datsun truck with the J13 had 4.875.

The 521 with L6 engine was 4.375.

Most 620 have a 4.375 differential. Early automatic 620s had a 4.625. The '79 620 manual used a 4.11 and so did the '80 2wd 720.

The '81-'82 automatic 2wd 720 had a 4.11.

 

Place an ad in our classifieds... http://community.ratsun.net/classifieds/category/5-drivetrain/?sort_key=date_added&sort_order=desc

 

An L head on a Z24 will require an L timing cover being lengthened 2cm taller and timing chain lengthened. If used with the Z24 transmission the intake with carb and exhaust will be hard over to the left about 20 degrees and maybe into the driver's side inner fender and steering column. Usually this swap is done by using an L transmission and mounting the engine in the L position leaning to the right. This gives room for the manifolds on the left.

Is it possible to use a toyota rear end?

[datzenmike]

If you change the entire rear axle over. Toyota trucks are 6 bolt rims.

[handsome_man_777]

So, i found a Datsun 520 and 521 rear end, with 4.3 gearing. Which one would work best? and Would I have to use the entire rear end, or will the diff swap out in my 720?

[datzenmike]

So, i found a Datsun 520 and 521 rear end, with 4.3 gearing. Which one would work best? and Would I have to use the entire rear end, or will the diff swap out in my 720?

Both these facts/question has been answered...

 

Datsuns use an H-190 differential and it's not totally necessary to take it apart and swap the R&P. The differential unbolts and with the axles pulled out can be changed as a unit.

 

 

The 520 Datsun truck with the J13 had 4.875.

The 521 with L6 engine was 4.375.

Most 620 have a 4.375 differential. Early automatic 620s had a 4.625. The '79 620 manual used a 4.11 and so did the '80 2wd 720.

The '81-'82 automatic 2wd 720 had a 4.11.

 

Place an ad in our classifieds... http://community.ratsun.net/classifieds/category/5-drivetrain/?sort_key=date_added&sort_order=desc

 

An L head on a Z24 will require an L timing cover being lengthened 2cm taller and timing chain lengthened. If used with the Z24 transmission the intake with carb and exhaust will be hard over to the left about 20 degrees and maybe into the driver's side inner fender and steering column. Usually this swap is done by using an L transmission and mounting the engine in the L position leaning to the right. This gives room for the manifolds on the left.

 

 

 

.

[captain720]

Wayno has some experience making the LZ23s.