s13 rear subframe in SRA s12! PIX AND UPDATES! 1/16/2012

[David B]

s13 rear subframe in SRA S12?

im not talking about it being easy to do also, i need a stable common rear end and multilink would be nice
whats anyones opinions on this, because this is my plan, i have a whole donor 240 ready to get cut up for it too. i also have a s12 fsm, though i do know SRA s12"s floors are different, but this is going to be a project with a tube bender involved. and also paying someone with some cage building experience to help me figure this out
LMK!

[d_k_jose_s12]

Good luck you are really thinking out of the box

[Jeremy A]

I know you have the skills to make it work man,  and the best way to figure out that first step would be to line up the subframe in the rear with the rear axle removed and mock it up.  Then you'd have to engineer the stress points. Thats just obvious stuff though, man,  I'm not very experienced with suspension settings or tuning (know little to nothing),  and I'm wondering why you'd go with a S13 rear setup over a different or replaced solid axle setup.  Will it be very advantageous for drifting and worth it? 

[sam31183]

enough cutting and welding time and money and shit can be done!

[cutter67]

maybe you should look at the Heidts multi-link kits i will be using one on my MG project and then you could run a ford 9" rear

[RB25sx - SLPR]

I've been through 2 complete iterations of the S13 rear end swap.. I have this to say: Whatever you do, don't take the quick road.

You will find that there is a crossmember that runs lengthwise between the two shock towers - this is perfectly positioned for rear rear mounts of the S13 subframe. It will need to be strengthened and then have circular flat mounting plates added.

The front mounts end up lining up a few inches shy of the factory S12 mounts but and interesting point should be that the diameter of the rod bolt used is the same on both cars - if I remember correctly it is approximately 22mm in diameter. But you are SRA so this is probably a moot point anyways come to think of it.

The first S13 subframe I swapped I modified the subframe itself, but then if you crack or damage it - you have to redo EVERYTHING (which, in drifting of course happened). So I would suggest designing entirely new mounts. What I have been trying to work on is essentially a floor sandwich.

A sizeable hole (big enough for a hand to pass through) is cut directly above the pickup point. I would then cut the mount out of an S13, clean it up, simplify it and weld a plate to it. Make sure this plate sits flush and true with the bottom of the floorpan (directly under the hole) and overlaps at least an inch all around. Seam weld the plate to floor, drill out all around it as well and spot weld.. Now reinforce the floor pan with a plate of an even large surface area continuing the spot welding and of course all around the edge.

I investigated using an epoxy similar to lotus to get maximum adherance but was not confident enough in my abilities to properly prep the surface, so the age of solution of 'add more steel' works here.

I am sure a similar process could be applied to the rear mounts, but you will need to cut a decent amount of trunk out in order to accomplish it.

Good luck!

-dan

[cutter67]

i think something like this for a mustang would work i think it would be a lot easier to make work

[Jay]

^This... Kinda

If the H190 pops on mine, I'm going straight to an Isuzu diff with a pneumatic locker. Or something similar.

Open when I want.
Locked when I want.

Modify the axle housing. And pretty much done for fabrication. Quick, easy, and if the diff pops. a LOT of others to go with.

[CamInHead]

Why would you want to take the OEM triangulated set-up and replace it with a fairly unremarkable parallel set-up as above ? I see no benefit at all from that, unless I've missed something ?

If I were to try such an epic adventure, surely it would be best to simply put in box-section around the mounts, as the factory would have done, and a fat pair of turrets for the coilovers ?
On a side note a DeDion set-up might be fun and a little easier. TBH I'd probably just be done with it and drift a 240 though.....

[I_heart_VVL]

Why would you want to take the OEM triangulated set-up and replace it with a fairly unremarkable parallel set-up as above ? I see no benefit at all from that, unless I've missed something ?

If I were to try such an epic adventure, surely it would be best to simply put in box-section around the mounts, as the factory would have done, and a fat pair of turrets for the coilovers ?
On a side note a DeDion set-up might be fun and a little easier. TBH I'd probably just be done with it and drift a 240 though.....

^that.

from what ive seen, the S12s SRA design is one of the most effective already.
I would just get some other rear axle, (hilux, supra, H233B, C200, ford 8.8, etc.) and just remove the old pickup points and tack on the S12 ones. done.
anything more than that just seems unnecesary unless your building a pro-level car.

[Jay]

anything more than that just seems unnecesary unless your building a pro-level car.

You can't do it with a pro-level car. Not even an amateur one.

Straight from the D1 pro-am 2011 book

3.3.2 Suspension Design
The basic OEM suspension design type may be freely modified. The original
suspension mounting “pick-up points” must remain in the stock, unmodified
location

and

3.3.4 Front cross member and/or front or rear sub-frame
Front and rear sub-frames and cross members must be stock and available
on the exact model that is competing in Formula Drift. The subframe must
also be mounted in the exact stock location, without being moved in any
plane.




Because the SRA never came with a subframe. You can't add one.

(IF you plan on going any higher with the S12, and into the D1 pro-am, anyway)

[cutter67]

the basic design of the s12 is good but if i was going to put the car on the track i would go with something like shown basic and strong will take a lot of abuse

[RB25sx - SLPR]

Keep in mind what David is trying to do here, 240 subframes and arms and coilovers are incredibly plentiful and cheap as shit in the real drifting community. It is a no brainer.

-dan

[I_heart_VVL]

You can't do it with a pro-level car. Not even an amateur one.

Straight from the D1 pro-am 2011 book

3.3.2 Suspension Design
The basic OEM suspension design type may be freely modified. The original
suspension mounting â€Ã...“pick-up pointsâ€Ã, must remain in the stock, unmodified
location

and

3.3.4 Front cross member and/or front or rear sub-frame
Front and rear sub-frames and cross members must be stock and available
on the exact model that is competing in Formula Drift. The subframe must
also be mounted in the exact stock location, without being moved in any
plane.




Because the SRA never came with a subframe. You can't add one.

(IF you plan on going any higher with the S12, and into the D1 pro-am, anyway)

wow!
iirc a year or two ago, they allowed pickup points to be moved up to an inch or two.

[Jay]

wow!
iirc a year or two ago, they allowed pickup points to be moved up to an inch or two.

Yep. And then this happened.
http://www.autoblog.com/2009/04/13/tanner-fousts-v8-rwd-scion-tc-formula-drift-car-unveiled/


In D1GP you can do it. But for Pro-Am. They decided it was best to not allow it. It would allow someone who would fabricate something leaps and bounds above the rest. So in the sake of actual competition, it better that you can't do it.

[David B]

look guys, im doing it because i get 240's like everyday. i bought a parts car in my back yard to have all stock parts for this swap,
i also want strut towers, true 240 coils etc. camber, shits gonna handle boss if its done right

Keep in mind what David is trying to do here, 240 subframes and arms and coilovers are incredibly plentiful and cheap as shit in the real drifting community. It is a no brainer.

-dan

i can cut the whole rear floorpan from my parts 240,

i was thinking using the s12/s13 frankenstein drive shaft bolted up to the carrier bearing would determining the length and pinion angle of the diff id want right? i have a factory fsm for reference, and my own DD too.

selling these t3 links and theis caliper setup will help pay towards it too...


i dont care about FD or D1 lol.
if i were to ever drive in those events id be driving a sponserd car i bet! its the only way.. lol. i just want a crazy ass car that will give me alot of seat time

[Jay]

Make sure it will fly. because up here, the midwest cup is governed by Clubfr. They follow the Pro-Am rulebook.
If I were to do that. I couldn't drift on the track again for the cup. I'd be limited to Ddays and lapping days.

But if you don't care. You don't care. I offered my input.

[CamInHead]

I think David just means he has no interest in building to specific set of rules - he just wants to improve his car.

[sam31183]

I still wonder how the old rwd tc has been allowed to drift for so long in fd after the rule change...they even built a new rwd tc this year for aasbo....but they wouldn't allow konstantinov last year to use an r32 rear end in his s13...its fucking stupid.

[D-sport S12]

I still wonder how the old rwd tc has been allowed to drift for so long in fd after the rule change...they even built a new rwd tc this year for aasbo....but they wouldn't allow konstantinov last year to use an r32 rear end in his s13...its fucking stupid.

FD is stupid