Driveline help/advice needed. s13/14 gbox. lsd.

[sexual_sushi]

My gearbox has shit itself (I assume). Its making a metal on metal noise in every gear except 4th. Best way to describe the sound is to picture a shaft spinning inside a case, but its lose so it can randomly hit the sides of the case. Only does it in gear, clutch out and it doesn't happen in 4th but it does in every other gear. So I'm deciding what to do with the entire driveline as I had plans for it anyway.

 

Here's a bit of info about the car (skip to the q's in bold if your bored )

 

Its a 73 240z with an l26 engine, pretty standard, just a header and electric dizzy, roundtop su carbs etc.

In the future I'm planning on a proper 3.1L stroker. I have triple webbers for it and plan on sinking as much as it takes to do it properly (budgeting for another $10000 atm).

 

This is just a weekend car. I have a daily driver 260z i drive to work everyday.

 

I'm 90% sure it has a r180 3.545 diff thats making a little whine atm. The gearbox is a 280zx 5 speed.

 

The tailshaft needs new universals.

 

 

What my plan is atm, is to replace the gearbox and do a s13/14 gearbox mod (ill keep the current box and rebuild it for me project car). A new aluminium tailshaft (probably a waste of money but this is my pony car). And I want an LSD, if im going to rebuild a diff anyways i might aswell rebuild an lsd. So I'm thinking I'll do all of these 'upgrades' now.

 

I suppose most of my questions will relate to the lsd but if anyone has any input on my plans feel free to put in your 2 cents.

 

I've read a bit about the s13/14 conversion and I think I'm pretty fine with the process. I'm thinking of the s14 box just because generally speaking it should be 'newer'. Just wondering if they are any other pros/cons between the 2 boxes? And if anyone knows of a pretty reliable place i can get good box from or do you think i should rebuild an s14 box myself? I don't want to put in a box thats just as bad.

 

 

With the diff, i understand that theres a few mods you have to make to fit an r200 diff but these seem to be the more common of the lsds. I would rather go with a 180 but i suppose I will also be limited by availabilty atm. I would also like to up the ratio to probably 3.7 or 3.9. There has been talk of using an r180 from an Sti and there's a guy on ebay selling them for about $1000. What I'm not sure about is what is needed to make them fit? I'm not sure about the halfshafts when it comes to lsd's. What would be the ideal lsd for me if i wanted a fairly simple conversion or what would you recommend for me anyways?

 

Would love to hear anyones advice or if you see any issues with my plans...

 

 

 

[sexual_sushi]

in regards to the subaru lsd conversion i found this good article... scroll down to the posts by 'Nizzan'

http://forums.hybridz.org/showthread.php?t=117916&highlight=sti+r180+lsd

[620Z]

OK I have had a bit of experience in this area. If you are planning on spending 10K on a high HP engine then I would with out a doubt get and R200 LSD. 3.9 ratio is the best all rounder. Shop around and get one. As for the tail shaft I have had 3 in mine slowly getting bigger. If you never want to have a problem then you should get one built with 1310 unis. This will be big enough almost over kill but you will never have to look at it again. I now have 1350's in mine same size as V8 Super cars. You will also have to look at your half shafts as the conventional ones may not stand up to the punishment. Will for a while but will eventually die. Z31 CV axles are the go there.

Sorry I can't help you with the gear box as I run a V8 but I am pretty sure most guys still run a standard box with a stroker motor.

Hope this helps

[PZG302]

Not sure on the gearbox conversion, I'm lucky enough to have a close ratio early 240 box and I won't be letting that go anytime soon.

 

As for the diff, personally I would run the R180, it's a lot less weight than a R200 and it should pretty well handle the torque of a L31. I know of R180's being used successfully in some pretty torquey sports sedans with no problems. If you were running an 8 then I would recommemd the R200, but as you said it will be your Sunday car then the R180 will be strong enough as long as you don't abuse it.

 

I run welded R180's in the following ratios depending on track, 3.9, 4.1 and 4.875. I have yet to break a diff with my race starts, generally 4500-5000 rpm and side step the clutch. The only problems I have had in ten years of racing the car has been one output shaft broken, an easy fix, and one diff destroyed when a cutomer at the shop that looks after my car knocked it over and spilt the oil cleaned the mess up and didn't tell anyone a week before we put that diff in the car. It lasted nearly 10 laps around Amaroo with no oil before destroying itself, a pretty good advertisement for the strength of an R180 I reckon, especially as being welded there is more potential for failure than in a standard or LS diff.

 

The cost of finding a R180 LSD will be about the same as an R200, or maybe a little cheaper, OZDAT would be a good place to look, or other rally sites as they are the most popular diffs for 1600's, and there are some pretty tough 1600's still getting round, especially those with the 2.4 litre L20B motors, the equivalent of the L31 .

 

My tail shaft is standard, but was balanced before being used in this car. I also use the standard drive shafts for the diffs, two diffs use the bolt in at each end and the 4.875 is the press fit at the diff from memory.

 

Another option fo rthe gearbox is to get a set of Hollinger gears or a set of Needham gears, cost will be around $5000 but will never break unless you are stupidly harsh on them, and you can pretty much get the ratios you want.

 

Hope this helps a l;ittle and gives you something else to ponder.

[sexual_sushi]

thanks for the info guys... exactly what i was after.

 

ill do some reasearch over the weekend about the z31 cv axles, im thinking I might aswell go the whole hog, all at once.

 

i'm still leaning towards the r180 a lil just beacuse it should be that little bit easier to do the swap. found some more info about the subaru r180 using stock 240 axles. ill post the link when i get home from work

[sexual_sushi]

thought i posted this already, maybe i clicked the wrong button :S

 

anyways,

 

ZZZ8 what sort of work is involved in swapping to z31 cv's?  Was just wondering if you would be able to give me a rundown on the process? had a quick look around and most of the info i found was in relation to shortening the shafts by reversing them.

[620Z]

Yeah I got a shop to do all the work on my CV conversion so I am no expert to be dishing out details of the conversion. There are a few people who can do it for you. I think they made up a plate on one side to adapt and get the length's right. It's a bit of money this conversion but worth it if you are going to do any hard work in the car. Plus I recon they are lighter than the original UNI's so that might give you a poofteenth more power as well!   :-)

[ZED660]

If you want to stay with an R180 LSD diff, providing you have the correct one, you may wish to consider the alternative in this link.  They are based in Melbourne and seem to have a good name.  The diff required is an R180 3.9 with the letter K on the top of the casing.

 

http://members.optushome.com.au/amaxeng/five10/diff.htm

 

 

[luvemfast]

Here is what I have used to use Z31 CV's in my car, I have an S130 so it will differ to S30 cars. But the concept is the same. I beleive you also will need 2 pairs of half shafts from a Z31, they are not even in length and you need the 2 shorter ones.

I highly recommend recessing hub into adaptor as shown here, it uses a dog type drive. Version 1 didn't and my car was left on the Haunted Hills track with sheared bolts. Should have known better, but I got lazy. Turned out to be an expensive day, $40 a lap plus trailer hire and petrol........

Lesson is do it once, do it right.

[RBZ 260]

Also RB20det boxes are similar to s13 and s14.. though s13 and s14 the stick position is further back by 2.5cm roughly.

 

as for cv shafts. i got it done to my 260z.

 

though running a R200 LSD the diff came with turbo CV driveshafts which came from R31 skyline jap import 2door. turbo shafts and cvs are bigger than non turbo. Z31 turbo and R31 turbo share the same diff and driveshaft setup.

 

the short version of things i done:

 

picked up a local Z31 turbo rear hubs and controll arms.

machined the 260z hubs slightly to accomodate metric bearings.

 

Installed the Z31 half shafts into S30 hub with appropriate bearings

 

Driveshafts race has been swapped in reverse also the circlip slots have been machined further down by 10mm.(i think) this overall shortend both driveshaft by appropriate amount.

 

than just bolted all together like it was made in factory.

 

also this made rear 5stud to match the front and used Z31 turbo rear disks and calipers. all pretty much bolted up.

 

i got more detailed write up somewhere on this forum and on www.thezgarage.com

 

been abusing it for last 7 months and still no breakages with rough driving and 200kw+ turbo engine in front of it.