S13 front end in RA23/28

[TA-022]

What a interesting idea Lambo ...

Im keen to see what comes out of this ... ive got the shell at home so if measurements are
needed gimme a holler.

[The Witzl]

no need for a custom front sump for the 18R - there were a few cars that came factory with an 18R front sump arrangement.... i even have one with the oil pickup at home

There are some very interesting and valid points raised here, definitely worthy of a deeper look

[Hen]

If RA23/8 and AE86 arms are interchangeable (and the same length) as suggested by Joel, then the options for the S13 conversion are basically the same as those for an AE86.

They are:
- Keep normal LCA length (possibly using TS Magna balljoint) and suffer positive camber.
- Keep normal LCA and adjust camber using camber tops. Hopefully enough adjustment possible.
- Lengthen your LCA to correct camber and increase track.

Hen

[Steve M]

Just checking here, LCA is for lower control arm, right?

I am looking forward to seeing what comes out as the best option here so that I can do it myself.

[Norbie]

no need for a custom front sump for the 18R - there were a few cars that came factory with an 18R front sump arrangement

While not technically necessary, a custom sump would be a very good idea. As correctly pointed out by Justen, the baffling in the stock sump is quite poor. Imagine destroying your brand new (and expensive) bottom end the first time you take a high-G corner. There would be tears.

- Keep normal LCA length (possibly using TS Magna balljoint) and suffer positive camber.
- Keep normal LCA and adjust camber using camber tops. Hopefully enough adjustment possible.
- Lengthen your LCA to correct camber and increase track.

I'd like to add option number 4:
Keep normal LCA length (possibly using TS Magna balljoint) and correct the camber by bending the base of the strut tube. This is precisely what I did in my MA61 (using MX83 struts) and it worked very well.

[TA-022]

But also not legal. i know its used in race applications blah blah ...stupid RTA.

[Norbie]

Hmmm didn't know that. Doesn't really worry me though, there's no visual evidence of bending so no-one will ever know.

[Hen]

I'd like to add option number 4:
...correct the camber by bending the base of the strut tube.

Bending the strut tube may not be an option given the S13 strut design. However the same effect can be achieved by slotting one of the 2 mounting holes where strut bolts to steering knuckle as shown in pic below. This always sounded a little suss to me, but should work.



Hen

[TurboRA28]

With an S13 strut could you not get some ecentric bolts to adjust the camber?

[Norbie]

Very interesting, thanks for the info! I wonder if it would be possible to use an eccentric bolt as used to adjust the rear toe in an MA61? That would probably be more secure than simply slotting the hole, and it gives you the option of adjustability.

EDIT: jinx! Same thought posted at almost the same time.

[TurboRA28]

This is all appealing.. But i get upset using non-toyota parts in my car.. So thats been the main thing holding me back from doing this conversion for years now. Even though there are many benefits.

Plus I never could get an answer on if the height of the outer tie rod would change, as then this will change bump steer.

[barned01]

I have been racking my brain on this for a little while as i want to use R33 brakes on my ra40.
also i want a 1uz so i need rack and pinion steering (possibly requiring the interim solution of a front sumped 18r from an rt130 or 140 or something) and 5 stud wheels.
(and in the back of my mind i knew the s13 strut solved almost every issue i wanted to reslove in my celica including 5 stud, r33 brakes and coilovers).
now as i think it is Cruz that has created an r33 brake upgrade using ra60/ma61 strut, i have been looking at options to use that strut on the RA40 (knowing that i will have to solve the positive camber issue somehow).
I took a couple of measurements of the ra60 front end (to work out how the geometry of the ra60 strut compares to angles and stuff), the KE70 front end (as i was thinking of Joel's upgrade), and of an RA40 front end (my setup and what i compare the numbers to).
I am not that familiar with all of the parts in a front suspension so you may have to correct me on my statements but looking at the picture below, these are the measurements i took of each of the systems.
what i call the lower control arm (the diagonal bar that goes to the bottom of the strut), this was the same approximate measurements on all the 3 setups.
the only things that changed were the distanced of the top hat and also the distances of where the lower control arm meets to the crossmember (and obviously the bolt holes for the crossmember to chassis rails).
I will get the rest of the measurments tomorrow as i hope this will all help to make this all easy.
If i have missed some required measurments, please let me know and next time i go to the wreckers, i will get those measurements as well.

[oldcorollas]

With an S13 strut could you not get some ecentric bolts to adjust the camber?

the S14 has larger holes, so if you use S14 steering knuckle (but a different ball joint again... we should look for both options S1/S14 is abotu same size but different taper.. go figure)
and there are offset thingies to allow use of S14 knuckle with S13 struts..

i'd be more interested in S14 conversion for the 5 stud. makes it even easier to upgrade to Z32/R32 brakes.

[jonra23]

The S13 has camber adjustment built in to it, it has a pair of eccentric washers that work in a slot, similar to inside of falcon LCA for camber, if not enough adjustment i planned in drilling one of the two strut to spindle bolt holes oversized in the spindle and pressing offset bush into it.

again if no-one has done it next 2 weeks will post some results.

Barned01, do you have the measurements from centre to centre on of struts and centre to centre on bottom ball joints?
That way can work out the angle of the struts, will get a mate to measure same on cefiro (same as S13) so can compare to give an idea if camber adjustment is going to be close enough.

regards
jon

[jonra23]

Probably all seen it but gives some of the measurments Barned01 was chasing plus a fair bit of other celica data
http://ourworld.compuserve.com/homep...m#Crossmembers

regards
jon