I've read through the FAQ but I am curious... how hard do you guys that have the IRS swap done drive your cars? It's a down-the-road mod i'm considering for my sedan but I want to be sure that the stresses autox and potential track time would put on the rear end of the car won't be met with the IRS ripping out of the car. (not something I want to have happn at speed mid corner)
any input?
Glad you brought this up, as a few of us were just discussing IRS swaps the other day, lol. This has been on my to do list for a while, and was going to actually do it while I have the car torn apart for the winter, but after seeing in the FAQ that the 4 "C" braces are the only contact points for the subframe to the chassis makes me a bit concerned.
I would think the the main weak point (if it is indeed one at all), would be that chassis/subframe joint. Definitely seems solid enough for day to day road time, but once you start throwing some side to side weight at it...could go either way.
I'd love to hear some feedback from anyone that abuses their set ups as well, lol
Could always bolt it and then throw a bead along both sides of it to keep it in there for good. Ive always been leary due to that as well.
I wouldn't worry about that a bit. It's fairly heavy gauge steel. The c-beam that guys have used has a thicker wall than our frame rails actually have. The lower control arms are actually more of a weak point than the subframe connection.
The other option, which I did, is to make a one-piece bracket that wraps up around the outside of the frame rails. This can be then bolted or welded in place.
This is exactly how the N-body cars have them mounted from the factory.
Planning a D-mod build? Using the GA IRS is in in way legal in street mod, SP, or P (maybe xp). I've figured out basically how I'd go about building a trailing arm setup that is legal in sm, but even its in the gray area of the rules and I'm not sure there would be much benefit to it.
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People put hitch receivers on the c channel and you don't see them pulled out. If you actually look at all the parts that make up this setup you would worry more about it.
leafy... I've already been through the rulebook... irs i believe could sneak in under prepared but not in combination with the blower... just looking at future options at this point.
just thought i'd get some input as cars that are autox'd/tracked tend to see higher loads than normal daily driving.
I've auto crossed and drag raced my 'vert.. I believe I was the second to do the IRS mod? But mine was the first to be bolted on, not modified like mcmoney did.
I drive it harder on the street some days than on the track - no problems here.
i was hoping you would chime in!
thanks lenko!
But what do you use for rear struts? To me not worth it to many things that snowball with that. Like brakes do you convert the front too wow! You almost have to!
see ya!
novaracer wrote:But what do you use for rear struts? To me not worth it to many things that snowball with that. Like brakes do you convert the front too wow! You almost have to!
We've been tossing ideas around for running coil-overs and the NWF swap isnt a bad thing......
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that and if i do the irs, i will exhaust all options to keep the 5x100
Saturn irs swap, that's what I'll be doing this spring. Keeping 5x100, as jbody hubs are swappable with Saturn hubs.
Its a little more fab work intensive, but totally worth it to keep the 5x100 imo.
The subframe mounting points are narrower on the s series, but i will be fabricating a cradle to mount the subframe to,I intend to weld the cradle to the j body frame rails. Its about as robust as your going to get. All I should have to change is the jbody strut mount on Saturn struts, or get 2 Saturn rear coilover assemblies.
Interesting....
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i don't know that anybody has looked into a 5x100 compatible hub assembly for the GA knuckles though. if you can find a bolt in hub assembly or even mod the knuckles to accept a 5x100 setup, you'll have alot less fab work into bolting in the alero rear.
strat81 wrote:i don't know that anybody has looked into a 5x100 compatible hub assembly for the GA knuckles though. if you can find a bolt in hub assembly or even mod the knuckles to accept a 5x100 setup, you'll have alot less fab work into bolting in the alero rear.
Jucnbst said he thinks he found one to work. Pm him or look in the other tread to see what bearing.
i thought he was talking front knuckle though... are the hub assemblies the same front and rear?
No he couldn't find a front one. He mentioned he had found a rear bearing already early in those post.
novaracer wrote:But what do you use for rear struts? To me not worth it to many things that snowball with that. Like brakes do you convert the front too wow! You almost have to!
Hey if you're going to do it at all, better to do it right. If not.. just stick with the beam axle.
Rear struts are N-body KYB GR2's. Rear springs are N-body Eibach Pro-Kit. Yes, I had to buy a second set of lowering springs just to "do it right" but I'm not willing to cheap out on suspension.
My front knuckles and control arms are N-body as well, and the brakes are C-body. 12" discs fill up the 16" GTP wheels very nicely. I have about 1mm of clearance all the way around.
strat81 wrote:i thought he was talking front knuckle though... are the hub assemblies the same front and rear?
Hub assemblies are completely different. Rear is a 4 bolt base like the J-body hub, but instead of being a trapezoid, they're rectangular. I've looked at modding the knuckles, but I'm not sure about it. Because of the different shape of bolt pattern, it's not a simple job.
I'm in the middle of doing a front knuckle mod, but as soon as it's wrapped up, I'll grab a spare rear knuckle and play around with it.
