Suspension Mods

[fjm9898]

hey guys. i need a quick hand.
I am not around much and havent really looked around this forum much although i have been a member for a long time.

Can anyone point me to a bunch of aftermarket suspension stuff for a 2g gsx?
i know there is a company that makes a tubular rear sub frame that is $2500 and billet front knuckles

SPC (or something like that) had aluminum front UCAs but they no longer make them.

what else is out there? i am basically looking to replace all the heavy suspension components and upgrade the others for a road course track car. so that means i am looking for a good sway bar setup front/rear. tubular arms and adjustable linkages where even possible. i will probably be getting the billet front knuckles, are there rears?

any info you can point me to would be great.
thanks for the help guys.

 

[snowborder714]

I'm guessing you don't have a budget?

Have you ever done road racing, or are you just building a car for it, then getting into it? Do you know what class you want to run in, as a lot of these parts will immediately put you up with the big dogs.

As a note, with the billet front knuckles, you have to custom fab all of the control arms, mounting points, etc. so you better know a thing or two about suspension geometry before using those parts.

If you have no budget and don't care about what this does towards your class, I can provide a ton of links to you. But some of these basic questions should be addressed first before you go dropping the equivalent of a new car on just suspension stuff.


I'd suggest starting with reading this thread front to back. Kevin has A TON of great ideas and is definitely putting time and thought into his build and not just throwing money at it.
Goblins AWD project - Mitsu-Media

 

[fjm9898]

You make alot of good points on the needed information

I will start by reading over the thread you linked me with.
But until then here is some information on my plans

Right now i am looking at an open budget. the car will be built first and running stock for practice/fun/learning and then receive the suspension overhaul.

i dont have any plans to run in official class. this would start as more of a weekend track car for fun. maybe some time attack if the car is allowed. it will also run drift at my local track (literally a mile down the road) i know i know i said drift, but i have seen evos and STIs toss down on the course for fun. as i gain experience and skill the ultimate goal will to run a series, but i am not getting my hopes up for that.

i read through the time attack FWD widebody thread (the car in the banner) i am sorry i forgot his name. i didnt see much else besides the UCAs but i am sure they have done more

I did not know those billet knuckles needed that much modification i thought they were direct replacement.

my original thought was to get as much weight reduction i could in the suspension components as well adding adjustability for messing with tow/caster/camber and roll centers.

so what do you think i should be looking at getting?

 

[snowborder714]

I would personally say the parts you're looking for are totally unnecessary, unless you really have that much money to throw around.

Also, I have never heard of anyone doing that much suspension work to a road race/TA car as most people don't want to be in that unlimited class. It's fairly rare for someone to really look that hard into a car and suspension and not be thinking somewhat competitively.

The money you'd spend on the rear tubular subframe and billet front hubs would probably net you very little gain without all of the other parts. I would suggest start looking into the following:

1. Coilovers.

The DG Konis are a great starting point for someone getting into autox/road racing, while the KW Variant 3 are a next step up, but with the additional cost. You can see both Kevin (from thread above) and Drew (white TA car from site banner) both used KW V3's with most of DG'sparts (uipper hats and standoffs, obviously adjusted to fit the application, as I believe they both use a 2.5" spring).

2. Sway bars.

The easiest way to get started with these is buy the RM DSM bars. They are a great price ($300) for the set and are direct bolt on parts. Or, if you want to get fancy, you can check out what Kevin did with his sway bars. I'm not positive with what Drew is running, but I do know they're pretty thick pieces.

3. Camber/caster adjustment.

You had the right idea on looking towards the SPC arms, so if you can find a set, they're a decent investment. Make sure to read up on all of the flaws in the arms though (ball joint issues, arm contacting strut tower, etc.). I have yet to see anyone make a custom UCA, as much as I'd love to. I've only seen one other person modify a stock UCA to give them more camber while utilizing an SPC bolt in ball joint.

As for more caster, this is another modification to the arm, while making sure you get the most amount of caster from your compression arms (do some searching and I'm sure you'll find some info).

4. If you want to address roll center, you can have the front subframe modified by RobiSpec. You can read a bit about it in Kevin's thread.

5. Wheels/tires.

You'll want something light, but still of good construction. Obviously the widest tire you can safely fit is what you want. R-comps are ideal for road racing.

6. Corner balancing and alignment.

This is big step once you get some decent suspension items. You'll want to take advantage of the coilovers and camber/caster adjustments, so you'll want to corner balance and then align the car to your specs, not the factory ones.


And there's a host of other things such as safety equipment, racing seats, harness, possibly a roll cage, etc. that you'll need to look into. Some of these things won't really seem important until you get out on the course. Once you do, you'll be able to start prioritizing what you want/need based on how the car drives. For example, I had seats way down on my list. But after my first HPDE, they got bumped way up after looking at the bruises on my knees from holding myself in place.



But the main thing you'll want to do is get behind the wheel. Throwing all of these parts at it can help, as long as you know what the car is capable of before modifying it. There's no real point of throwing all of these parts on if you have no idea what the car does when you drive it. It could be driving fine, you throw on everything, and it oversteers like crazy. Now how do you determine what caused the oversteer? If this was my weekend fun car, I would not want to take the time to troubleshoot 6 different possible causes.



Just for more info, here's the link to the billet hubs.
Magnus Motorsports » Blog Archive Magnus Billet Wheel Hub |

I sent Marco an e-mail a little while ago to see if he had a list of anyone running those, as I was interested in what it'd take to fab up everything. He provided me with one name, and here is the link to his build thread so you can see what he has gone through. Keep in mind he drag races the car.
Getting ready for showdown

 

[fjm9898]

Thanks.

I wasent going to purchase that sub frame as its more geared towards drag race and seems like more then i would need. I have a good Fab weld shop here i am working with and we were thinking about making tubular subframes for the weight savings. we have even spoken about redesigning the front subframe to change the car up to RWD. but digress, haha.

As far as going nuts with parts, i want this car to be an example of something built right, not some hack job. With that comes the ability to run competitively at a high level in the end. so i dont want to be purchasing parts now only to replace them in a year or two when i go to step up later.
Yes i want to start slow in the goals of what kind of competition i am running in but i want to start with a solid foundation to learn from and advance with into those higher levels of motor sport and bring the car with me.

At this point i would agree things like those knuckles would be over kill, but i am willing to open the checkbook for extreme parts.

Thanks again for the insight. Once i get done reading that Goblins thread i may ask about some more fancy over kill suspension parts. not that i may be buying them but i would like to see whats out there for the future. maybe buy them now in case that go out of production like the UACs did.

 

[snowborder714]

If you can build a car once and done for road racing on your first shot, I'd commend you. It's a never ending learning process. Heck, I've only done one road racing event and have already changed some stuff (suspension and UCA's being main items). So don't look at it from trying to build the car once. I agree, don't buy shit parts to know that you'll have to upgrade them later. There are some very knowledgeable and talented road racing/TA people on this site, and others, that you should be able to build at least a solid first go at the car.

I believe the subframe is geared somewhat equally towards drag racing and road racing. One issue you'll find is there's no sway bar mounting points on it, so that's one thing you'd have to add, if bolting it to the subframe is how you plan on going. But I seem to remember Marco saying they've used that subframe in both types of cars and it's performed great.

 

[fjm9898]

Sounds Good.
I agree that going from Zero to Hero is just not going to happen but as we spoke about i surely dont want to have to buy things 2 or 3 times.
My local fab shop might give this sub frame thing a try seeing how i would like both a front and rear, might as well have them do both, and i could have them add in the mods to play with roll centers.

are there any must have parts you can think of that i should look into down the road that i should buy now even if i wont use them at the start. like i said i dont want to see more parts go out of production on me like the SPC UACs did.

 

[snowborder714]

Nothing I can think of at the moment. As I mentioned before, even the SPC arms aren't perfect. There are plenty of known issues with them and the company has no plans on fixing them. Everything else that I've mentioned is either going to be custom or will always be available in some way, shape, or form.

 

[fjm9898]

reading kevin's thread he put spherical bushings in the SPC UACs. that fix the issues or are their others that would need to be addressed?

 

[snowborder714]

That is just so he can remove all bushings from his car and gain full movement/travel of parts like the control arms. That doesn't address it possibly contacting the shock tower or the ball joint issues they tend to have.

 

[jtmcinder]

My $.02. There are two kinds of suspension-related weight reduction: sprung and unsprung. The latter is close to an order of magnitude more important. I would only be thinking of custom subframes if you need to move the inboard pick-up points, such as when you need to fix the roll center height on an overly-lowered car; I wouldn't go that crazy if all you need is to drop weight. Dropping sprung weight off the bottom of the car is not that useful. When it comes to sprung weight, you start at the roof and work downwards.

 

[fjm9898]

i understand that point. the reason why i was going with tube sub frames mainly was just to do it, push the boundaries, have some fun, as well as have the few gains of adjustment and weight savings. This isent going to be a budget build by any means so might as well toss the whole book at it huh? haha.