IRS update in preparation for motor swap

[essdeezee]

Hey guys

 

I’ve got a ‘71 240 and plan to go with an ls1/t56 combo up front and I want to have a setup out back that can handle that sort of power for street and autocross use. I also would like to improve the braking at the same time, and I favor the idea of using oem nissan stuff over other possible choices. And before the usual question is asked, yes, I am well acquainted with the search function and have used it extensively.

 

Handling an ls1’s torque output is going to require something stouter than my stock rear end and U joints. A r200 with a CV conversion seems to be one way to do it, but that would leave me with my sad old drums handling the braking.

 

To deal with that issue, I could go with any one of the rear disc conversions, such as the 280zx rotor and 200sx caliper with maxima brackets, or possibly the z31 rotor/s14 caliper/ MM bracket. But by that point, I’ve already replaced practically everything back there.

 

Those setups seem to have worked for others in the past. However it seems like quite a hodgepodge of parts. This brings me to my question: Is there a currently known way to deal my issues in one step, such as using the r200 from an z32 with corresponding mustache bar as well as the 5 lug hubs, rotors and calipers from the z32, and connecting the things with some permutation of CV’s? Essentially, attaching the package to the stock lower control arm and finding a cv/stub axle/adaptor/whatever setup that would allow it to connect to the r200.

 

I know that anything is possible given enough time, money, and fabrication skill, but I would like to know if this is a worthwhile avenue of research. I am rather budget minded, so this sort of setup would allow me to either acquire the pieces over time, or buy the whole rear end out of some z32, if I found the opportunity.

 

I plan on doing this before the engine swap because it is a more affordable step, and one that I will be able to enjoy as I save for the swap. Should I never quite make it to the ls1/t56 swap, the proposed rear end would probably be able to hold up to any sort of beating a L series motor could dish out anyway, and I would have been able to go to 5 lug hubs and great big OEM Nissan disc brakes.

 

If you’ve made it this far, thank you, if you have constructive input, well, even more thanks!

 

Mark Spies - San Diego, Ca.

[260DET]

The whole rear end out of another Nissan thing has been discussed before, lots. If you are thinking Z32 consider the extra track width that will give at the rear, plus five stud hubs of course. S14 is a better choice, still wider though, not sure how much power those tripod CV's will take but I'm told for drag racing the outer stub axles are the weak point.

[Pop N Wood]

We have had guys run 9's on an R200 and U joints, so don't know that I agree with your basic assumptions.

 

The majority opinion here is R200 with some type of LSD, the CV conversion and at least 280 stub axles (if not Ross's billet stubs). Drums are actually adequate and don't need to be replaced. The one big advantage of rear disks is they keep the wheel with the car should a stub axle fail.

 

Not sure what is hodgepodge about this set up. All Nissan parts. Not sure how Nissan would have done it differently. In fact, add the 240 SX rear disks and you will have exactly what I plan to use with my 71-LS1-T56.

[essdeezee]

I dont mean to sound picky or condescending, but I'd prefer that the post was at least completely read before replies were sent.

 

I have no intentions of drag racing this project, in fact I specified that it was a street/autox build.

 

260DET- I wasn't planning on swapping the entire rear end. If you had read my post, at the end of the fourth paragraph, you would have seen the question that I was asking, which was: is it reasonable to swap the r200 in, and attach the hub/rotor/caliper to the stock lower control arm and connect the two with some combination of adapters, stub axles, and CV's ? In this case, track width wouldn't be an issue

 

 

Pop N Wood- you make a good point about my assumptions, however, I want to go to a rear disc setup and 5 lug hubs anyway, so I figured that going to one OEM assembly could simplify matters rather more effectively than the combination of the CV conversion, a 5 lug hub conversion and whatever brakes are available at that point.

 

One of my big questions is: provided the hub/rotor/caliper can be attached to the stock lower control arm, would shortening the distance between the hub and differential cause a problem for any CV because of the angles involved?

 

Thanks again

[JMortensen]

In response to your question about somehow attaching the Z32 hub to the S30 control arm, I don't think its feasible, because the Z32 doesn't use a strut setup.

 

But you can make a completely custom strut, like Jamie T is doing:

http://forums.hybridz.org/showthread.php?t=104649

http://forums.hybridz.org/showthread.php?t=100758

 

I think he had another thread that he started about the custom strut, but I can't find it. I didn't try too hard, so dig a little bit and you may run across it.

[fastzcars]

Here's another way using z31 partshttp://forums.hybridz.org/showthread.php?t=82357

[Pop N Wood]

260DET- I wasn't planning on swapping the entire rear end. If you had read my post' date=' at the end of the fourth paragraph, you would have seen the question that I was asking, which was: [i'] is it reasonable to swap the r200 in, and attach the hub/rotor/caliper to the stock lower control arm and connect the two with some combination of adapters, stub axles, and CV's [/i]? In this case, track width wouldn't be an issue

 

You may want to tone down the rehtoric. Part of your problem is some of these guys are thinking several steps ahead of you. Track width is absolutely an issue since that will dictate the length of the half shafts. Your problem isn't angles, it is length.

 

provided the hub/rotor/caliper can be attached to the stock lower control arm...

 

A very good question, but a very questionable assumption.

[260DET]

Yeh, some of us have researched and discussed the sort of issues being raised here at length, as pop said track is an issue because it relates to the length of axles etc. But anyway, for what its worth I've finally decided to fit the entire S14 front and rear suspension sub-assemblies into a S130 which will be powered by a 500whp VG30DET.

 

It just seems to me that when big power is involved its worth looking at using entire sub-assemblies, the good stuff available for upgrading S14 brakes and suspension alone make it worth while.

[essdeezee]

@Pop- I apologize for the rhetoric. I guess it was laid on a bit thick. But, now you're getting what my question was about! The heart of it is half-shaft length, and whether there were any possibilities of using a shorter half shaft and the stock lower control arm to keep track width near stock, while taking advantage of z32 bits. Thats why I stated that track width wouldnt be an issue with the setup I was envisioning and I was asking about angles. I guess I wasnt really clear. I had assumed you understood that I was speaking of shortening half-shafts, and hence, potentially different angles than the z32 half-shafts would encounter in a stock configuration.

 

@260DET- I agree with you on the idea of using entire sub-assemblies that were designed to work together. However, the level of fabrication required seems to be a touch out of my depth at the moment. thats why I was seeking a slightly different solution, where I wouldnt have to do serious fabrication, just the attaching of the hub/rotor/caliper assembly to both the strut and the lower control arm. This would keep me from having to screw with strange problems with camber and toe because I'll have a setup that is the same design as stock, just with different bits.

 

 

so, i guess, now that we've got the rest out of the way.....

 

Is it possible(or more accurately, reasonable) to shorten the stock z32 half-shafts enough to make this possible? if not, could other bits, like porsche 930 CV's with adapters make this fit?

[JMortensen]

Search for 930 CV conversion. A couple threads on that have been around in the last few months. Blueovalz and ezzzzzz (not sure how many z's on that one).

[260DET]

Someone used Supra half shafts too, I'm sure the link was reposted not long ago.

[essdeezee]

hey, thanks for all the great responses. the answer to my question was actually found in the links that jmortenson posted about jamie t's custom strut setup. I appreciate the help guys - mark

[blueovalz]

Here is the 930 axle use for my Z. It uses all Datsun components except the parts between the companion flange and the R200 axle (the halfshaft basically). But, the adapter plates must be machined, and the axles must have new grooves cut in them, and then shortened.