SpecB alumunium control arms and trailing arms on a GT?

My usdm spec.B has a cast rear diff carrier, steel subframe though.

If you had a bunch of suspension mods already, you would likely notice the difference in unsprung weight, but it's not going to be night and day. For the price of the lca/rear trailing arm, I really don't think it's worth it on a lgt.

I don't know too many people who have done the conversion, but I have.

Let me dig up the weight differences for you, but know that it is a very small return on investment. The academic difference alone was enough for me, and the aesthetic difference is a bonus.

The subframe did not change between the GT and Spec.B.

Here are the weights for the suspension pieces. I replaced the rear "forward" (camber) and "rear" (toe) links with the Whiteline adjustable control arms, which are probably slightly heavier than stock.

The differential cradle is maybe a pound or two lighter than the steel version, but being entirely sprung weight, makes vanishingly little difference.

I did notice a subtle improvement in handling, especially with the addition of the trailing arms. The car felt more "nimble".

As an OEM parts dealer, I can provide pricing on these for you, if you are interested.

Front Control Arms:

Steel 7.5lbs - Stamped and Welded Construction

Aluminum 6.5lbs - Cast/Forged Construction

 

Rear Trailing Arms:

Steel 17.8lbs - Cast Construction

Aluminum 11.2lbs - Cast/Forged Construction

 

Upper Lateral Links:

Steel 4.9lbs - Cast Construction

Aluminum 3.3lbs - Cast Construction

Thanks for the info guys! So im looking at a 20lbs difference.

I have jdm specb rev a struts and springs with 06 specb rims going on soon so im just trying for a full spec b package.

Yeah, just under 20lb difference. For the cash though you could be well on your way to a 6MT+R180 swap, which is going to be leaps and bounds more bad ass and tangible than the aluminum arm swap.

I'll never do a 6spd swap although I do wish I had DCCD. I am looking into a front LSD though.

I picked mine up from Rallispec back in November. I was concerned that parts for the V5/V6 JDM STI will start becoming more scarce now that it has been 10+ years since production. They were able to provide it very quickly and without trouble.

You can get 5MT DCCD if you watch the JDM auction pages.

Just did it few weeks ago... and I can tell the difference.

http://i261.photobucket.com/albums/ii56/fx35bl5/89FDB4C8-3D67-47B1-BB7F-306DC52FF77A-4136-00000BEFC898639A.jpg

Maybe harder bushings make difference too.

Pricey bling unless the actual geometry is different I always thought.

But if my pockets were quite a bit derper, I mean deeper, I would say hell yeah.

I picked mine up from Rallispec back in November. I was concerned that parts for the V5/V6 JDM STI will start becoming more scarce now that it has been 10+ years since production. They were able to provide it very quickly and without trouble.

 

You can get 5MT DCCD if you watch the JDM auction pages.

theres a bunch of JDM part outs here in Canada. can I steal any 5spd front lsd and use my 4.11 ring on it?

Just did it few weeks ago... and I can tell the difference.

 

http://i261.photobucket.com/albums/ii56/fx35bl5/89FDB4C8-3D67-47B1-BB7F-306DC52FF77A-4136-00000BEFC898639A.jpg

 

Maybe harder bushings make difference too.

As DD, this statement would be false. As the track monster this car is, this would be true.

Swapping out a heavy wheel for a light wheel plus lighter weight tires will have more effect for less money.

When I did my car, I looked at doing this mod. For purely aesthetic reasons, I wish I had done it. Then again, had I had that kind of money I'd be on AST 5300's instead of cheap c/o.

i did the fronts with bushing upgrades as well

def noticed a diff.

did the rear lat. links too

but jeez those trailing arms are pricey!