RA24 + MA70 suspensions

[tacoma_kyle]

Hello everyone. While back I was lucky enough to be allowed to this forum but have mostly lurked.

Soooo I will say first and foremost that this is a SLOW CONVERSION. I did accomplish a bit this summer in the last month, but school is starting again and I have a senior project this year....will get time in on this when I can.

I have a RA24 and had a predicament. Weak ass rear end and I am not a fan of live axles. Solution, 150 bucks got me a entire MA70 IRS with a LSD in fucking good shape.

300 bucks got me a car shell with the IFS.

MA70 suspension (and powersteering... nice) in my RA24. USing FSM's I am trying to replicate the suspension assemblies alignment with Toyota's factory set-ups. Figured they knew what they were doing...

I am just going to add some photo's and explain what I am doing tomorrow. I need to go to sleep.

I WANT FEEDBACK!

All of you here from the future just generally have better practices than people in the US when building your cars. Input on chassis strengthening, alignment advise, etc is wanted!

Having said that, I think I have a good handle on this. But let me know whats on mind.

Prior to hack. Dont ask on the suspension, it was modded and not stock. By me. I has changed though...obviously0


IRS layin under the car. Nothing special, just a good sitting place for it.


IFS...prior to cleaning.


IFS where it is staying. I havent welded it in yet. Maybe tomorrow if I get time.


The rear of the MA70's chassis that will get fabbed into the car eventually. Hopefully before winter (3 months).

[tacoma_kyle]

Oh yeah...questions as to what I am doing, why, etc are great. There are peculiarities that I chose to do.

[MWP]

Hey Kyle, good to see you on here

We didn't get the RA24 in aus, just the ta22, ta23, ra23 and ra28.
I wonder what the difference is to the RA23.

Anyway, won't be much of the ra24's running gear left by the time you've finished.

Using the a70's rear will be a big improvement, but I wonder about the front.
Double arm front instead of the mcpherson strut will be an improvement if you can get it right. Youll probably end up needing adjustable arms.

(written on my iPhone, so excuse any spelling mistakes, etc)

[twentyEight]

Kyle,

A guy in Canberra here in Aus is doing the exact same setup in his RA28, so the following threads should give you some info for your conversion.

Part 1 - http://www.toymods.net/forums/showthread.php?t=5785
Part 2 - http://www.toymods.net/forums/showthread.php?t=7107
Part 3 - http://www.toymods.net/forums/showthread.php?t=24607

[brett_celicacoupe]

isnt there a mega track difference between the 2 cars?

[tacoma_kyle]

Ok...more

MWP, I think the differences are minor. Other than you guys got some different engines, tranny's, nicer bumpers and thats about it. Oh and the right hand drive thing. Well I guess those are some pretty big diffs lol.

Thanks for the links twentyEight. I got a kick outta how at the end of #3 he decided to just cut up a Supra. I kinda went that route....'oh I can modify it....but....this....this....that....' It added up. I am extending the wheelbase though. Primarily because I have a 1UZ+W58 that is sitting patiently to get put in. I needed to be sure the sump would clear, so I gained about 3" on the wheelbase. Yeah....fender mod time. Comes later toward the end though.

brett_celicacoupe, yeah there is a pretty big track diff. Probably 12-16cm over the entire width of the car. Flange to flange. I am going to be doing some body work.

I am also lowering the CG. That is one big objective I have. If I just tried to attach the subframes to the chassis rails, the car would look like a AMC Eagle. Crap load of ground clearance. Or at least thats my suspicion based off on the fly measuring. I figured since I am cutting into it, I should drop the chassis as much as possible. Limited by the front shock attachment points.I think I dropped it by about 2.5cm. THen using the MA70 FSM online, take the body reference dimensions, make my own reference line, then align the back so that it matches the Supra's chassis. But not length-wise.

On the front, it is apparent that I could have made a effort to more easily aligned the RA24 and MA70 chassis rails. But I needed it that long (A70 rail) to get the sway bar attachment point.

[Steve M]

I'm glad to see someone who isn't afraid to take on a big project.
Great start, I look forward to seeing the rest.

[tacoma_kyle]

Here is an update. I am keeping up on it. This is pretty much what I wrote in v-eight.com. But FYI, as ghetto as the car looks, it is leveled appropriately and there were numerouse measurements taken as well as level usage to make sure the suspension is properly aligned.

This morning I did do the final trimming for the rear Supra chassis section and have it sitting within a few mm of where it will forever. It is horizontally (acorss the width) leveled great. Just need to do some final adjustments. Project for this evening. But unfortunately I lost the angle grinder lock-nut. Fuck. Well at least I got this far before I lost it...

But here is the front, as it sits. Need to get more sheet-metal. I believe it is about 1.5mm (1/16") or so thick. Little thicker than the Celica or Supra sheetmetal. Well some of it. Like mentioned, I am waiting on solid wire and a regulator for the welder. FC is a no-go for continuous welding.


Here is a side shot with a 17" IS300 wheel on it. Notice the length difference. Fenders will need some intense modifications.


This was the hole as of a couple days ago.


This just shows a couple angles of where the suspension is going to pretty much sit. Note that it is only the chassis section, not the suspension. That is in the garage. Once I get it legitimately tacked in place, I am going to jack the IRS up to make sure I am happy with the hub center location at full droop (with shock in place). No matter how many reference measurements you make, a visual gives you the confidence that you didn’t supremely fuck up.

[toyo-al]

Nice work mate, I'll be watching this come together

[Sagluren]

very interesting..

cheers sam.

[CELICASUPRA7M]

this concept blows my mind.
your so ballsy, your balls have balls haha

[MWP]

Awesome work Kyle, good to see your still working away at it.

[SLO-030]

AWESOME work!

Kinda got a bit depressed when i got to the end of the thread. Definatly keeping an eye on this!

[Scoobzd]

I'm sure there's sum infringement of Toyota copyright model details there but

HELL YES anyways !!!

[tacoma_kyle]

Thanks for the comments. Scoobzd, it'll be funny if I ever get it aligned. I think logically if money isn't a significant issue, it may be drivable in 6 months. Hard to say. That ignoring the Wilwood calipers, big rotors and other springs/dampeners I would like to get.

Update for today. I will do some more later on, but I wanted to bolt the suspension in place to make sure I was happy with how it was laid with respect to the front.

The photo’s below show the wheels/tires bolted in (about a inch less offset than the stock *A70 wheel, per [by that I mean narrower]) and I blocked the suspension to within about .125” of the shock at FULL DROOP. So I am guessing it will site about 2” deeper. Maybe less, as this car will probably weigh in the range of 2600-2700lb. That’s my guess. Everyone seems to say RA28’s stock are about 2200lb, so I am basing that off the addition 220lb that is probably added to the rear (the A70 shit is fucking heavy, like complete IRS about 400lb with shocks and I think no wheels, added it a while back). Probably about 80lb added to the front. +80lb from me using the A70 seats and I guess about +120 for the engine and whatever else. Then minus whatever I gutted out. Lots of light shit. So yeah.

As you may expect the suspensions are officially not going anywhere. Haven’t done shit on the front, I need tips for my welder. Going to look for some in an hour. But yeah, the rear it tacked pretty well and is fully supporting the estimated 400lb of suspension parts. Bolted up just fine. Even got it up by myself. Went a bit easier than expected, really.

Measurements…
-So before putting the tires on, I blocked the suspensions to full droop so I could measure the vertical difference between the center of the hubs. The rear is about .25-.5 lower than the front. Which I believe to be desirable. I dot know the travel numbers, but generally the rears have a little more than the front. The FSM’s body dimensions page didn’t have anything useful to find ride-height hub centers.
-The wheelbase is now about 102.75”. I don’t know the original RA28’s wheelbase, but it was probably 98-99”.
-Width-wise on the rear. There is probably about .0625-.125” of play between sliding the IRS forward, back, side to side before tightening the bolts. Using a level, I measured the distances to the edge of the body flare from the brake rotor surface on the hubs wheel-flange. Came out pretty much identical. Just an arbitrary number, but they were the same, so that’s fucking awesome. Guess this goes to show you don’t need a perfect paved garage to build shit! Makes it a lot easier and cleaner, though.

I think if I dropped the car the rear would support the cars weight fine, I have a crap-load of tack-welds. But need to do it fully and paint it before I drop it. Rather do it right the first time. The front may, but I wouldn’t want to push it yet.

Anyhow this was kinda fun. Cut cardboard shapes and made the chassis section extenders. I modeled it first for the fuck of it. Turned out pretty accurate, but it didn’t do me any good. But yeah. Anyhow, that was a little of a PITA. Abrasive cutoff discs are nice. Would have been nicer to water-jet it all. Anyhow. Went well for what it was.


Umm what else……….. Going to try and find a stock A70 gas tank and fuel pump. Think it’d be the easiest way to go. Wish I did this way back. Spent too much on random shit, Cressida parts, van parts, celica shocks, SC400 fuse box, etc. Lots of time wasted. Bleh. Especially at the fucking wrecking yards pulling parts. This, I have all of like 450 into the car and suspensions. Just a lot of fab time and buying abrasives and blades. Anyhow…