With all the talk of IRS on 3rd-gens, has anyone done a strut to A-arm conversion up front?

that doesn't make much sense seeing as how the car already has an a-arm on the front with macpherson struts.

I would assume you mean replacing the strut with an upper A-arm? Kinda old-school technology at work there.

uggg more parts to wear out. IRS on a 3rdgen -I personnally like live axle better. now if your talking about front suspension how about rack and pinion conversions.

Ummm, yeah. Double A-arms up front... As in, the PROPER suspension for a car.

The one so "old-school" that GM went back to it after playing cheap with struts.

You know, the kind of suspension that race cars use. Well, at least the ones that TURN do...

Yes, I'm looking to see if anyone has done a double A-arm conversion up front, with or without a steering rack conversion as well.

Just wondering if there's others, or if I'm gonna be first....

Fatal88 switched to the 4th gen from end.

CPCamaro...cheaper, faster ,lighter my friend

Why would you want to spend all that time money and effort to convert it? I'm not being a smart@ss here, just asking. Seems like you would be adding alot of weight to the front end of the car for very minimal gains if any? What is it that you don't like about the strut front end?

No need to get chippy around here, no one learns from that

Thirdgen F-bodies have some of the best lateral performance numbers out there, for the cost at least. Most third gens can out handle 4th gens, I for one plan to keep the stock setup, but its its up to you.

A coil-over kit would be more worth your time. After all, the coil over shock method is one of the things that gives the 4th gens their "superior" ride quality. The springs don't have to be as stiff, so it feels better despite the 3rd gens better handling.

But the thirdgens advantage is mostly do to the lower roof-line, and wider stance I beleive.

I know that the stock specs for my GTA place it at about a 47" roof height. 4th gens are around 50" I believe.

*edit: 4th gens are 51" tall and have a width of 74". 3rd gens are about 47" tall, and also 74" inches wide.

Which makes the 3rd gen 4" shorter on average. For comparison a Ford GT40 is about 40" tall, hence the GT40 in the name sake.

doesn't a "wider stance" go by wheel base and not actual car width? I just thought 4th gens were wider because the rear axle is 3" wider. But then again, I dunno **** about tire offsets.

I couldn't find specific information on how wide it was hub to hub. Though yes, 4th gens have a wider rear, but the hub offset is also greater in the rear.

Putting 3rdgen wheels on a 4th gen rear usually makes them stick out further. Where as putting 4th gen rims on 3rd gen rear without spacers would cause the wheels to "tuck" in under the body more.

So it may be that despite the different widths of the axel they DO have the same width wheel to whee.

Can't make up for 4" inches height difference with the stock suspension though. 3rd gens rule!!

in that case i've never seen it done and you sir would be the first to my own knowledge. i personallly wouldn't venture that way because of room. one would spend a pretty penny changing things over but i suppose no different then a tubular a arm conversion and coilover setup. too each their own, go with it if you like.

I'm pretty sure most all Porsches have MacPherson-strut style front suspension, and nobody complains about them.

What would you have to do to make a setup like you are wanting anyway?

It seems like the smart thing would be to start with a tubular K-member setup already made and then get all the locations pinpointed where you want the upper control arm on the chassis, then get a spindle that would accept the lower control arm's and upper control arm's ends. Looking inside the fenderwell there doesn't seem like there is enough height from the lower control arm to where the K-member meets the frame to put the upper control arm far enough away upward.

Or maybe you could get a 4th gen K-member setup and cut/weld it to fit in our front subframe. I haven't ever looked too closely but I think I remember the 4th gen front suspension having much less caster than ours... so you might have to cut and weld the strut towers as well.

Or, complete original fabrication.

Or, 4th gen front clip minus firewall, weld up, then you have body panel fitment issues I imagine, if you still want it to look like a 3rd gen in the front.

Where is that pic of the engine bay with the 4th gen front end on the 3rd gen firewall? Is that car a 4th gen front body style as well?

I found the pic... in here...

scroll down 4/5ths:

https://www.thirdgen.org/techbb2/sho...50#post1829650

Not trying to get chippy, just noting that real race cars that turn don't have struts.

The issue with the struts is twofold.

One, lowering a 3rd-gen ruins it's front suspension geometry. The front roll-center heads for the ground, and mine is right at ground level. A good way to salvage the struts would be with drop spindles (hence my earlier post about anyone having a set), alas, nobody has any.

Two, wheel backspacing. My car has 12" wide slicks all the way around. The front wheels can only have 4.5" backspacing before they hit the strut. I can fit double A-arms in the wheel and make a 0-scrub-radius suspension.

I'm pretty sure a new crossmember will be in order, but that part is easy. It's the upper arms (whether WAY up as on the 4th-gen, or lower as in a stock-car) that will be a pain...

Get aluminum strut mounts they help when lowering.

well ya know here's my 2 cens on it..

the long arm short arm can be done with some fabercation using a b body front k member(monty carlo)

now.. as far as the benifits... i think it's not worth the money and work, i do understand why you would want this setup but why unless you are just racing the car would you want to spend that kind of money.. i understand that in a hard corner you would benifit from the long arm short arm setup the tire to pavement would have a wider contact patch-where the modified macferson setup would loose some contact patch in a HARD corner. i think that when a car comes to hadiling that alot has to do with tire/driver/condishions.. but with "money" ANYTHING can be done..

as far as the "real car" thing. i think that's bs there is people that have a modifed macferson setup that can handle as good or better than a long arm short arm it's all about the money..

hope this helps chirs

lol please explain how they help with lowering?

now there are people that have made aluminum spacers that go between the strut mounts and the fenderwells that compinsate for the geomitry when the car is lowered.. also there are outer tie rod ends that compinsate the geomitry (bare bakes bump stear kit) in the steering.

Explain ? what dont you understand. They are taller so you get more strut travel when its lowered they wont be as compressed. You dont want the shock to ride out of the sweet spot in normal conditions. Most shocks will have a by pass channel that will be fatter in the center so during normal driving more fluid goes by for a softer ride. Then when they compress it gets smaller= less fluid goin by and stiffer shock for a hard corner.

These medium height mounts provide extra travel for lowered and non-lowered cars. A must for those looking to do some serious corner carving, and you can't beat the trick look they provide to your engine bay! qutoed off the spohn site..

sorry.. i was not aware of this i was under the impression that they where of stock dimentions..

Ha yeh ill get some eventually they're kinda exspensive dont yah think.

yea i got the black one's last year when i did mine.. and i thought that was alot.. im thinking of makeing some spacers for mine..

You've been watching tooo much NASCAR. Many a car that will turn circles on a road track around a NASCAR with upper controlarms. Lets see- Audi, Porsche, BMW, Mazda, to name a few that have been seen on quite a few world reknown road circuits holding lap records with strut suspensions.


I'll help you out and solve your 1) roll center problem, 2) lowering (lack of drop spindle) problem, 3 gain neg camber from increased strut angle- all with one miricle product


Whaa laa- Longer stud lower GM balljoints
http://www.colemanracing.com/section/index.htp?id=1337

There goes another one of my until now guarded secrets.

what dean, no mention of that helping bump steer, or the fact that the billet strut mounts will also help raise the roll center slightly.

Hey thanks... I was looking at those, but it looks like they only go 1/2" longer than stock. Now, if they made them 2" longer, that would be ideal (at least for spacing, not sure how strong it would be).

I know Porsches, et al use struts, and that they handle... But, they're also production chassis in classes that only allow that. They don't have the option of converting.

If an engineer has a choice, I have yet to see one pick struts for better handling. When I do, I'll reconsider...

I've had extended upper strut mounts for some time now. They're similar to the Spohn silver ones. My my car is low enough that I can't use the Spohn torque-arm crossmember because the angle plates he uses stick down lower than the crossmember (and anything else under there). I modified the stock crossmember to pickup the Spohn torque-arm mount.

Just so y'all know, CP in my name stands for C-Prepared, as in SCCA autocrossing. It is more of a race car than anything else.

there is some fudging room with the a-arm angle, before things get really bad. It will of course lower your roll height no matter what. but you should be able to get at a point where you can make it work, with a PBH relocation, and the right springs and sway bars.

hmmm, being in CP, you can do pretty much anything you want. i wonder if you could get creative with the strut/spindle mounting area, and raise the roll center back up.

My choices with the stock arrangement is to either relocate the lower A-arm mount points upwards on the chassis, or use a drop spindle to raise the wheels, enabling me to extend the spring.

Problems are, the stock K-member is not friendly to relocating the arm, and Belltech no longer makes their 2" drop spindle for 3rd-gens.

The extended lower ball joint would help some, but not enough.

The tubular K-members for 3rd-gens might enable relocation of the lower arms, but then, converting to A-arms would enable me to use any arm angles and spindle I want.

Hmmm....

CPC, I am curious to know how far off the leaders in your class your are locally and how much time you expect to be dropping with such a convertion. Assuming you do pull it off with hours of fabricating- it will take several events if not a season or two to dial the bugs out and TRY to perfect the new setup. You are getting into black forrest stuff and unless you have access to very sophisticated programing and measuring scales, you are going to hurt yourself more than help yourself (mostly finacially). I have a streetcar right now that will clean up on any third or fourth gen car in the corners on the local tracks here in So. Cal "on street rubber"- I just don't have the power behind it yet to makeup for the long straights. These cars can be dialed to perform very well if you know what do. I do

ps, ran it once about a year ago in ESP against 10 other cars. I was only a V6 with aprox 165hp on street tires against the competition all on racing rubber and 300-500hp range. I took 5th of 11 and .18 behind 4th. I only have this car dialed for fulltime street use, not track.

Well, There are 2 top-10 national cars in my region, and 5 of the top-10 national cars are in my division.

I'm not that far behind them, but I know the car isn't right. The torque-arm arrangement is only half effective (it really needs a 3rd-link instead) and the front roll center is so low, it feels like a bus.

Frankly, I'd love to find a set of 2" drop spindles, leave the struts in, and beef the strut mounts. That would be cheapest.

However, if I can't do that, I have to get that roll center back up somehow, and it's lower than a 1/2" longer ball joint can fix.

The struts are OK, but I don't think anyone here runs 12" wide tires up front with them. Like I said, I can only use 4.5" backspacing before the wheel/tire hits the strut. This also makes coilovers up front impossible, unless I stick the wheels out even more. As if I didn't already have enough scrub.

If I have to convert it to use a more common set of spindles, I might as well make it take advantage of double A-arm camber/caster curves as well.