Z32/S13/S14 - multi-link rear suspension swap

[FlawleZ]

[quote]craZed wrote: [quote=phxZ31]

Yes, but the HICAS isn't the only differance. You can eliminate the HICAS and still have the benifit of the r230, the beefier half shafts and the beefier stub axles that the others dont have aside from the q45 SF.
Didn't all Z32's come with the R230 diff? I thought the only difference was gear ratios between the TT and N/A diffs.
Nope the NAs had r200s. You are correct on the different gear ratios, 3.7 for the TT and ~4.1 for the NA.

The TT's had a the R230 3.69 rear end ratio while the NA's had the R200 4.08. Among the differences are the axles, ring gear diameter, the output flanges, some of the subframe mounts...etc.

[Gritt]

z31 axles will just spin in a q45 vlsd unit. been there, done that. learned that lesson the hard way. something you guys arn`t thinking about is this. s13 subframe, j30 vlsd, q45 aluminum spindles and for the 5 lug, the j30 hub assemblies. bam whamo, almost a perfect setup. you might have to use the j30 rear brakes and if so you lose the better s13/z31 style e-brakes.

my whole thing is getting the center line of the wheel centered in the wheel well while having the subframe empty so you can move it around, all the while rolling around on your back.

[SATAN]

Ford Falcon wrote: Hmm, very interesting mod.
I have a Z31, and a donor '90 Q45 in my garage. The Q has had its engine removed and I am about to get rid of the rest of the car. Based on what has been discussed in this thread so far, If I go along with an S13 rear subframe swap, given the Z32NA and Q45 share some similar parts, what parts of my Q45 rear can I use (should I hang on to) before I get rid of this thing?

Dont know if you still have the car or not after this long, but if you do here is what you should hold on to.

Differential, input shafts to the differential, and the half shafts. You will need all of this in order to make a custom set up on your z31. See here. http://www.z31performance.com/forum/vie ... f=3&t=8220

[SATAN]

Ford Falcon wrote: Thanks Satan!
I got rid of the car, but I did keep the differential and half shafts too. I read your posts on that link. Very interesting indeed. You have obviously put a lot of thought into having a reliable setup. I will do the Q45 diff internals swap into the Z31 diff case, as you showed. If you have any pictures of what you did in order to make the hybrid Z31/Q45 half shafts, I would be most grateful.

My Z stock rear sub-frame will also get swapped for an S13 sub-frame so I can eliminate that inherent rear squat.

WHOA WHOA hold on there. If you are going to swap out to the S13 sub frame then there is no need to swap over the Q45 carrier into the z31 case. The Q45 case bolts right up to the s13 subframe! :yahoo. Well, you have to get the 240sx diff cover but still... Pretty easy stuff if you have the subframe installed already!

As far as the hybrid half shafts go, you wouldn't even need to to hybrid half shafts at that point. Search around on some 240sx stuff. What they do is take two of the same half shafts and put them on the car. Something like the driver side half shaft on both sides or something like that. Like I said you gotta search for it. It shouldn't be to hard to come across though because it has become a very popular swap.

EDIT: Here it is: "300ZX TT Driver Side Axle (installed on driver side of 240SX) and Infiniti Q45 Driver Side Axle (installed on passenger side of 240SX"

Read this, http://forums.nicoclub.com/zerothread?id=267924

[Butter]

So yeah...how come nobody is doing this?

I was going to fab up a prototype for a kit for Touge Factory to make the S13 rear subframe a total bolt in affair. Then I realized that nobody would buy it and crushed the car it was going to go on. Here are the super secret blueprints.


TF has an adapter block to adapt S14 subframe to an S13. It's basically a solid chunk of aluminum that replaces the forward rubber bushing.

I was going to take a blank one and drill and tap it so you could install it in the subframe and bolt an extension bracket to it. The rear would just be a box and stud assembly to envelop the frame member of the car (I posted a pic of this earlier). It would be secured in place with through bolts and the stock diff mount studs.

Somebody make them and make billion$$$.

[Ford Falcon]

Satan,

Doh, you're absolutely right! Thanks for that link too!

Hey Butter,

I'm doing that!! I have been busy with rebuilding the VH45 that will be going in my '88 Z31. The rear will be the S13 sub frame, Q45 diff (with S13 diff cover), Z32TT driver side half shaft, Q45 driver side half shaft.

Warning: dumb question approaching...
What hubs, hub assembly, calipers, etc should I be using with these half shafts? Do I need the hub assembly for the half shaft from the corresponding vehicle, or does the Z32TT / Q45 hubs interchange? Is there a preference?

Butter, if you have fabbed any components to get the 240SX subframe to fit to the Z31, I'd be interested. 8)

[Butter]

The shafts spline to the hubs and slide in.
http://forums2.freshalloy.com/showthread.php?t=172393
Keep in mind that if you are doing the Q45 diff along with your swap you just need the propshaft fitted with a Q yoke when you get it made, so no drilling. That should give you drag guys even more incentive to do the subframe swap.

Other Pumpkins that fit S13 subframe....

89-94 240sx OEM VLSD
95-98 240sx VLSD (with S13 diff cover swapped on)
90-96 NA Z32 VLSD (w/ pre 95 J30 axles or 180sx axles)
95+ J30 VLSD (with S13 Diff cover)
Pre 95 J30 VLSD (w/ 95+ J30 axles OR 180sx axles)
180sx VLSD with its own axles or pre 95 J30 axles

The Z31 Clutch LSD carrier should fit in the S13 open pumpkin

[Chris86NA2T]

ive been becoming more and more interested in this swap after recents posts.. i doubt id be doing this any time soon if i even decide too, but i have some questions that im trying to figure out, so ill post them here with the hopes that someone has the info..

1. Butter, a few posts up you said that the z31 lsd carrier should bolt into the short nose r200 that comes in the s13.. Do you know if the splines are the same? Id like to use a short nose r200 from an s13, install my long nose r200 clutch lsd carrier and have it bolt up to the s13 halfshafts.

2. Did anyone ever get a hat to hat measurement for the s13 subframe? My wheels are pretty much as far out as they can go (17X9, 24mm offset, 275/40 tire). In fact they rub the inner fender in really hard turns. It would be nice to know that the measurment is equal to or smaller than the z31.. You can always space the wheels out a bit if you have to, you cant pull them in.

3. It would be nice to know the measurement from the ground to the bottom of the subframe bushings in an s13 subframe.. meaning take a factory s13, put it on a level surface and measure from the ground to the bushings.. while these numbers would not carry over to the z31 body, the difference between them should remain the same.. for example, if the front bushings were 10 inches off the ground and the rears were 18 inches off the ground then when the subframe is installed in the z31 there should be an 8 inch difference in height.. This would be very helpfull when trying to get the proper up/down angle.

4. Aside from spinning the diff and counting revolutions, is there and easy way to tell which S13's had which gear ratios? This would make junkyard hunting easier.. Im having a real hard time finding this on the web.. I probably just suck at searching.

5. Regarding ride height, how will a straight up s13 swap sit? Butter, i remember you initially having trouble with your car sitting properly and you ended up making taller strut mounts out of huge pipes or something. I think that was with the longer s14 struts, correct? Do you think that stock s13 struts will be close enough that there will be some range of adjustment with off the shelf coilovers?

6. All s13's were 4 lug, correct? some research has shown that its very common to convert to 5 lug. I found these conversion hubs: http://www.jnrmotorsports.biz/ichiba...conversio.html the bolt pattern is not specified at that site, but im sure that with a bit more searching ill find that info.

I think answers to these questions would be helpful to anyone doing this swap. Again, i dont plan on doing this any time soon, but i do find it interesting. If my research yields any answers ill post them, and if anyone has answers please post them as well.

[OK85ZX]

Chris86NA2T wrote:
3. It would be nice to know the measurement from the ground to the bottom of the subframe bushings in an s13 subframe.. meaning take a factory s13, put it on a level surface and measure from the ground to the bushings.. while these numbers would not carry over to the z31 body, the difference between them should remain the same.. for example, if the front bushings were 10 inches off the ground and the rears were 18 inches off the ground then when the subframe is installed in the z31 there should be an 8 inch difference in height.. This would be very helpfull when trying to get the proper up/down angle.

5. Regarding ride height, how will a straight up s13 swap sit? Butter, i remember you initially having trouble with your car sitting properly and you ended up making taller strut mounts out of huge pipes or something. I think that was with the longer s14 struts, correct? Do you think that stock s13 struts will be close enough that there will be some range of adjustment with off the shelf coilovers?

6. All s13's were 4 lug, correct? some research has shown that its very common to convert to 5 lug. I found these conversion hubs: http://www.jnrmotorsports.biz/ichiba...conversio.html the bolt pattern is not specified at that site, but im sure that with a bit more searching ill find that info.

I think answers to these questions would be helpful to anyone doing this swap. Again, i dont plan on doing this any time soon, but i do find it interesting. If my research yields any answers ill post them, and if anyone has answers please post them as well.

3. The people who are running the swap are doing it with the mounts flush against the stock z31 mounting surfaces so I don't see this being necessary.

5. Butter used an S14 crossmember with S14 struts, not the S13 equipment. He had to raise the towers because of the longer S14 coilovers, which you can find measurements of the differences in this thread (thanks to bum).

6. The 5 lug swap is very common and yes, I believe the only 240's that had 5lug were the hicas/lsd models.

You should read his build thread over at ziptied if you haven't already.. it will probably answer a couple of these for ya.

[Butter]

Whoa, I like questions like these. Makes me think something will happen.

1. Butter, a few posts up you said that the z31 lsd carrier should bolt into the short nose r200 that comes in the s13.. Do you know if the splines are the same? Id like to use a short nose r200 from an s13, install my long nose r200 clutch lsd carrier and have it bolt up to the s13 halfshafts.
Your Z31 CLSD should fit fine, there are a couple S chassis guys using them I am sure. Search their forums for this.

2. Did anyone ever get a hat to hat measurement for the s13 subframe? My wheels are pretty much as far out as they can go (17X9, 24mm offset, 275/40 tire). In fact they rub the inner fender in really hard turns. It would be nice to know that the measurment is equal to or smaller than the z31.. You can always space the wheels out a bit if you have to, you cant pull them in.I believe it's 60.5" at the wheel mount surfaces. You can always get those insane flares that dude is making in the cosmetic forum. You need to do this! :-D

3. It would be nice to know the measurement from the ground to the bottom of the subframe bushings in an s13 subframe.. meaning take a factory s13, put it on a level surface and measure from the ground to the bushings.. while these numbers would not carry over to the z31 body, the difference between them should remain the same.. for example, if the front bushings were 10 inches off the ground and the rears were 18 inches off the ground then when the subframe is installed in the z31 there should be an 8 inch difference in height.. This would be very helpfull when trying to get the proper up/down angle.
Do not worry about measuring this. Get the rear mounts all the way up to that crossbeam then try to slightly adjust it to level the pinion flange with the bottom of the Z. If you accomplish this, you will have the correct subframe tilt.
4. Aside from spinning the diff and counting revolutions, is there and easy way to tell which S13's had which gear ratios? This would make junkyard hunting easier.. Im having a real hard time finding this on the web.. I probably just suck at searching.

You suck at searching. Almost all S-chassis came with
4:11's.
5. Regarding ride height, how will a straight up s13 swap sit? Butter, i remember you initially having trouble with your car sitting properly and you ended up making taller strut mounts out of huge pipes or something. I think that was with the longer s14 struts, correct? Do you think that stock s13 struts will be close enough that there will be some range of adjustment with off the shelf coilovers?

Yes, my setup is a huge distraction to anybody looking at it. Let's take a few things into account here.
Jason has S13 coils installed on his stock shock mounts and seems to have no prob with adj range.
I just measured my car from the ground to it's S14 lower mount, it's 7 3/4". What do you get when you measure the Z? How far is it off? I believe S13 is in the same spot. This point is difficult to measure, so it's not a very accurate method, but it should give you a good idea.
6. All s13's were 4 lug, correct? some research has shown that its very common to convert to 5 lug. I found these conversion hubs: http://www.jnrmotorsports.biz/ichiba-24 ... ersio.html the bolt pattern is not specified at that site, but im sure that with a bit more searching ill find that info.

5x114.3 There are a few brands and methods out there. New Nissan is pretty close in pricing.

[Shirodet]

Chris86NA2T wrote: 4. Aside from spinning the diff and counting revolutions, is there and easy way to tell which S13's had which gear ratios? This would make junkyard hunting easier.. Im having a real hard time finding this on the web.. I probably just suck at searching.

All 240sx (89-98) had 4.08 rear ends, not all of them had a vsld. The only s13 to have a vsld stock is the hicas model (good luck finding one of thoes). In the s14 most se's and some le's had vslds and all s14s with abs have a vsld no matter what the trim level is (se, le, or base).

[Butter]

No. It would be too much work to weld the S13 piece into the car and have it still be straight and strong, assuming it would even fit. Besides, it's preferable to mod the subframe, not the car. That way you don't cry when you ruin your chassis.

What is the part# for the S13 rear spike things?

[Racinjitter]

For anti squat the Z32 is the best. Then from best to worst for anti squat; s15, s14, s13, z31. Which all of you draggers can appreciate?

[OK85ZX]

I haven't been able to find much difference information aside from some untranslated japanese tuner videos that I sort of understood there was a change of angles between them... it seems to cause a measureable difference... however the amount of additional effort/resources involved in swapping in a crossmember from the later years made me decide against it... as most people claim the difference is little more then negligible in a real world situation. Z31 -> S13 should far overshadow any difference between s13/14/15

[OK85ZX]

karay240 @ hybridz.org wrote:
S13: The most narrow one of them all. Which is why many Z owners consider it the choice for their swaps. You get decent traction w/ a lot of antisquat built-in w/ the front of the lower control arm tilted up. This makes for a stable feeling when accelerating, but in reality, you’re not getting the desired weight transfer (traction.) That’s one of the reasons why the S13 tends to break loose w/o much notice compared to the S14, and have limited traction out of the hole @ the strip. (this is true w/ the S13, R32, and Z32) . We’ve modified a subframe for an R32 we have here to eliminate this problem, and if you’re interested in similar things, you’re more than welcome to come & check it out.

R32: Everything from the S13 applies here, except the GTR subframe is substantially stiffer, and in theory, will handle better. But instead of the toe control arms it has HICAS, so you’ll need the HICAS eliminator bar for things to work properly.

S14: The theory of “newer = better” does apply here, in that Nissan took the good parts of the S13 subframe, and improved on it. Some of the differences are that they are a little wider, the upper control arm is more service friendly (anyone that’s changed the suspension on both of these cars know what I’m talking about. lol), addition of braces underneath the lower control arm, and the mounting points for the lower control arm are more parallel w/ the ground (less antisquat.) This lower control arm mounting has helped out w/ the traction issues of the previous model.

R33: Everything from the S14 applies here, except the GTR subframe is, again, substantially stiffer, and in theory, will handle better. But instead of the toe control arms it has HICAS, so you’ll need the HICAS eliminator bar for things to work properly. This improvement in traction is why you’ll notice that every S30 w/ a multilink setup has the R33.

S15: Pretty much it’s the same as the S14 subframe, but the lower control arms and the frame itself got more bracing. Stiffer = more traction. The subframe bushings (isolators) are different also, but not really applicable for this crowd. You’ll see several shop demo cars/drift cars from JP w/ this subframe on their S13/14. one final difference, though, is that the higher model S15 (turbo and other limited versions) came w/ a helical/torsen LSD instead of the VLSD like the previous S chassis cars.

R34: blah blah, stiffer than the s15, blah blah, HICAS, blah blah.

Z32: Wider than any of the above, but very similar to the S13, R32, and the G50. Many might suggest to go w/ this subframe for high HP cars due to the bigger R230 diff. It’s true that the TT model has a bigger R230 diff (non-turbo version has an R200); however, the stub axles are pieces of crap, and tend to break. Even high HP Z32 like the Escort Z has the GTR R200 diff. Another advantage to the R200 diff has more gearing options than any other Japanese cars.

So. The major differences are the slightly altered mounting points. Stronger is mentioned as an advantage in a lot of them, however you can be creative and strengthen any of them yourself. You can get slightly better geometry going with the later years, however you lose ease of fitment the wider things get. Going off of people who have already done these swaps, the S13 subframe mounted puts the hubs at almost exactly the same width as the Z31 subframe, so the only thing you have to worry about is making sure your wheels don't hit the coilovers. S13 coilovers also keep roughly the same height as a Z31 shock setup so you don't have to raise the upper mount like those who use the S14 subframe (butter, tempestas, etc) and can keep the stock one taking out alot of fabrication. The wider the subframe is from there, the more problems you start having with wheel fitment (start looking at custom wheels if you want wider than stock), and modifications to make the dampeners fit.

My opinion is still that the S13 would be the best choice for Z31 as I believe the ease of the swap and the lower overall cost is a larger benefit than the small subframe differences. This is only my personal opinion though, so take that for what it's worth


Also... the shorter distance from hub to hub there is, the more dish you can have