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ghetto3
02-10-2011, 02:03 PM
I need to replace a bent rear control arm and lateral link on a ba and seem to remember a picture of the v6 control arms being tubular in design as opposed to the pressed steel 1.8 versions. Can the v6 ones be fitted with no mods, to the 1.8 ba? Are there any strength related benefits, or should (could) i box my pressed steel arms (new ones) like i did with my torana ones years ago?
Btw are the v6 ones hard to come by, I like my kidneys where they are!?

Rupewrecht
02-10-2011, 02:44 PM
The V6 ones are a direct fit to I4. The V6 ones are a lot stiffer than the I4 in terms of twist force, but i double you'd notice much difference in terms of driving. I wouldn't bother boxing them - they're just there to keep the wheels in place. If it was RWD then it's probably make a difference.

project.r.racing
02-10-2011, 03:02 PM
i didn't know the rear latteral link were different between the 2.
i know the rear trailling arms are different.

Rupewrecht
02-10-2011, 03:06 PM
Sorry yeah i was talking about trailing arms

http://rupewrecht.com/astina/wheels/trailingarms_comparo.jpg

http://rupewrecht.com/astina/wheels/trailingarms_comparo2.jpg


Edit: I've got my old I4 ones if you need them

ghetto3
02-10-2011, 03:28 PM
Yes i will definitely get them off you, what would $damage be and could they be sent up with the rims?

Sorry yeah i was talking about trailing arms

http://rupewrecht.com/astina/wheels/trailingarms_comparo.jpg

http://rupewrecht.com/astina/wheels/trailingarms_comparo2.jpg


Edit: I've got my old I4 ones if you need them

Rupewrecht
02-10-2011, 03:36 PM
Yes i will definitely get them off you, what would $damage be and could they be sent up with the rims?

Ah $20 for the trailing arms and they're yours.

mig360m
03-10-2011, 11:37 PM
why dont u weld some steel in them. My friend did this to his BG trailing arms to make stronger

ghetto3
04-10-2011, 04:07 AM
That was my 'torana' mod, a strip of steel was welded along the U section to form a box section. The difference was noticable as in i didnt need to keep replacing them every few months.Hard to pass up that $20 offer though.
The BA had been in a rim buckling accident before i got it and im pretty sure this was cause of bent arm, it sits with about 3mm clearance from tyre and you can hear it rubbing when cornering enthusiastically. There is a rub mark on tyre also.

why dont u weld some steel in them. My friend did this to his BG trailing arms to make stronger

project.r.racing
04-10-2011, 07:47 AM
Can someone explain the difference between the two? I look at it and think the V6 trailing arm is just extra weight being pulled around?

Latteral link prevent side to side movement of the wheel, the struts/springs prevent up and down movement to some extent (bump/rebound). But trailing arms? They do not flex, they just stop the wheel from moving forward/backwards in relation to the chassis?

Yes on a RWD car, if the forwards/backwards happens, there is gonne be dynamic handling issues as the axles twist in relation to the chassis effect your thrust angles. Especially in solid axle RWD cars.

But on a FWD car with independent suspension all round, is this gonna be a major issue? To me no. But I'm happy to be told different. As the above dribble is only a theory taken from knowledge/experience.

Rupewrecht
04-10-2011, 08:29 AM
Can someone explain the difference between the two? I look at it and think the V6 trailing arm is just extra weight being pulled around?

More clearance for wider rims - that was the only practical advantage that i could see when i upgraded them. There was a slight weight increase but it surprisingly wasn't much at all. I supposed being tubular, it'd be less likely to bend, but if you've done something to bend it in the first place them you've got other issues lol

project.r.racing
04-10-2011, 09:04 AM
Oh? Is it hollow? If so, wouldn't it be weaker due to all the bends vs straight one? Same principle as sway bars? Every bend added allows extra flex. Weight issues would be nothing. I thought is was solid for some reason. Looks like it does have extra welds on the bushing tubes.

My 7.5" wide rims are still 30mm from the straight version.

There must be a reason for the difference, but other than the wider rim theory, I cannot see it.

Rupewrecht
04-10-2011, 09:37 AM
Yeah it's hollow. A lot stiffer than the I4 one though - that one can be twisted by hand.

As to why? I have no idea. Maybe something to with the extra G side loads put on it by the bigger tyres/wheels of the V6...but i can't imagine that being much different in the real world.

Clean_Cookie
04-10-2011, 09:56 AM
There must be a reason, why spend twice as much on r and d and have more parts to make...