2WD S10 setup for road racing

[brock1949]

As i've mentioned in a couple areas I have a buddy of mine who rents out road courses for club events a few times a year and I've attended a couple of these in the past. Trucks been down for coming on two years and its finally going to be ready to hit the road and the first event looks like its going to be end of May. I'm not sold that i'll be getting to involved with formal racing in the future but i have some really pushing me to goto autoX etc but i do want to take it into consideration if it becomes an option.

So far it doesn't do terrible, I had no problems pulling on camaro's mustangs most of the heavy RWD cars and it will by far blow all of themout of the water stopping (stock) and staying stable stopping.. not lifting the rear etc. But i do feel like it pushes the front end fairly easily and had a couple times i had to stomp on it to get the back loose enough to get the whole truckg going the direction i wanted.

currently I have:
Brakes
Ed miller C5 vette calipers using Hawk HPS pads on Ls1 Z28 rotors and pad size, Rear is factory blazer almost 12" vented rotors with vented aluminum calipers running Hawk HPS pads (was told its the same as the LS z28 rear brakes). All braided lines etc Kumoho Supra 712 tires 245 wide, 16" ZQ8 wheels (only reason i didn't goto 14" rotors Ed offers in this setup)

Suspension Front
Beltech 2" Drop spindles
Beltech 1" coils
Jimmy SLE 1.33" front sway
Beltech nitro shocks
Poly end links etc

Rear
Beltech leafs 3 leafs in the pack
Beltech 1.25" sway
Beltech nitro shocks
Cheap traction bars slightly modded
Fuel cell, Meth cell, pump &s filters all mounted in the bed

This setup is fairly tight and the trucks predictable but doesn't launch in a strait line worth crap and i'm not sold is that solid to begin with. I have a after market tubular lower A arm i planned on fitting a nice atjustable Qa1 coil over to in the front, and planned on doing a normal 4 link with a 5th cross bar in the back with 2 Qa1 adjustable coil overs.

Probably doing the rear first since its holding me back from even really getting into the strait line fun but would really like some input from you guys with more track time in a truck.

thanks in advance guys

 

[rentedmule]

Re: 2WD S10 setup for road racing

Fixing the camber curve will help with the plowing issue and give you more grip in the front. In stock form you'll get positive camber gain as the suspension compresses, leaning the wheel out and eating the outside edge of your tires.

Swap in tall upper and lower balljoints (0.5" longer stud) and get a set of UCAs designed to make the most of them. That combo will raise the roll center, give you negative camber gain in compression and get rid of most of the bump-steer. The tall lower BJs also lower the front by 0.5". If you don't have them already you should also pick up a set of the progressive ZQ8 bumpstops - it seems funny that such a small part could make a difference but they actually help quite a bit. The pro-touring G-body guys have been doing this stuff for a long time, even down to the ZQ8 bumpstops.

SC&C offers a complete kit with adjustable UCAs and Howe modular balljoints or you can get cheaper non-adjustable UCAs like I have from UB Machine and get the tall balljoints from power performance (less than 1/2 the price of the SC&C kit). The difference in grip is pretty incredible, it completely changed the feel and balance of the truck on the track. It also helps a lot with tire wear if you race regularly.

From what I've heard the Belltech coils are also pretty soft, most guys stick with ZQ8 coils. Coilovers aren't necessary - if you aren't using them to set ride height you can get the same benefits with an adjustable shock.

I have nothing useful to add about the rear end, my current setup is pretty useless.

 

[Philntex]

Re: 2WD S10 setup for road racing

Didn't see it in your description of mods, but are you running any type of "posi" in the rear?

 

[brock1949]

Re: 2WD S10 setup for road racing

thats fairly awesome info thanks for taking the time..puts allot of the odds and ends i've heard about these longer ball joints together. I'm not sure of the brands UB i'll search around and see or any links you could provide for ball joints and LCA and UCA would be cool. I have a set of lower control arms that i've been told 5 different things about not sure of the brand etc but they are 2" drop LCA tubular. Not sure if it was going to make much of a difference or not. The biggest reason i like coil overs was just ride height, Only one tech guy so far has given me crap telling me "I would kill everyone on the track with supercharged 4.3 on that high center of gravity" everyone lived.. But it would be nice to be able to really bring it down for track days seeing how it'll show up on a trailer then bring it back up for the street but i'm not saying i HAVE to go this route.

The rear end is a 8.5 30 spline 54" 2wd 5spd 01 big bearing blazer rear, 3.42 gears wtih the G80 gov lock/gov bomb rear.. Once i know what gear ratio this new motor/turbo/and 4l80E swap is going to like i'll probably be changing gears and going with eaton posi or some kinda true trac etc. I might dump the whole thing before its messed up and go with a ford 9 but its hard to walk away from these 8.5 setups when they come with a 11.8"? something close to 12 vented rear with parking brakes if i ever find someone who can crimp cables decent.

 

[brock1949]

Re: 2WD S10 setup for road racing

also i planned on mounting fuel cell on pass. side towards the front of the bed i figure it really should be over the axle but i don't know if i can talk myself into it. Planned on facing them backwards so the fuel lines were safe between the front of the bed and the tanks that way if i leave a folding chair or something in the bed and slam the brakes on i don't split a fuel line etc. I have a 5ish gallon fuel cell for meth injection in the bed which is an overkill for this setup but i used to run a TON of it to get enough fuel for a supercharge vortec 4.3 with TBI injection. So the game plan is lighter meth tank (whole setup is about 30lbs on the drives side front of bed then fuel cell 16 gallon on the pass side since i'll already be holding down the drivers side with plenty of weight.

 

[rentedmule]

Re: 2WD S10 setup for road racing

Marcus at SC&C is a guru for G-body suspensions and he's a really nice guy. If you want to spend some money call him and tell him what you want to get out of the truck and he'll set you up. He'll also talk your ear off so be prepared!

http://scandc.com/old/suspensions.htm#streetcomp2

A few of us 2wd guys were too cheap to go that route so a member on a few of the different S-series forums, dusterbd13, had UB Machine build a non-adjustable, best-compromise version of the tall ball joint upper control arm for much cheaper (~$65 per arm powdercoated). They're harder to get now because the guy who did the design work at UB Machine was laid off but they can still build them.

http://www.ubmachine.com/

An extra benefit of the UCAs is that the bushings are steel-on-steel and they're infinitely smoother than the stock rubber things. The new suspension geometry makes the ride much better on the street too.

Power performance started offering the tall BJ's after the S10 and G-body guys bugged them for a cheaper version of the Howes. They are good quality pieces and compare well to the Howes in strength from the numbers I've seen (although Marcus would argue differently).

http://www.powerperformancemotorsports.com/category.sc?categoryId=29

You'll have to change your alignment specs to suit the new geometry as well.

I don't know much about the LCAs. Most of the pro-touring guys feel that there is limited benefit to changing out the stock ones unless you want the extra mounting strength for coil overs. They can give a bit more caster as well but I'm not sure that's absolutely necessary.

My truck is probably much higher than yours (I'm at ZQ8 height plus 0.5" lower BJ drop) and I've never had an issue with being too high on the track. It corners extremely flat for the stance. I still wouldn't risk it with slicks though, I'd rather slide than roll! I'm not happy with my G80 - it's a lot better than nothing but it's hard to keep it locked on corner exits.

 

[brock1949]

Re: 2WD S10 setup for road racing

again .. great info i just found the UB site when you sent that i thought for sure it was short for something i would never find.

how much of the G body stuff compares to the S series, I've heard some people say allot of its the same etc its hard to follow.

If i stick with the normal coil route what spring is the heaviest? Zq8? factory? I could actually run a factory coil i have 2" spindles, 2" coils now and the control arms i have are supposed to be 2" drop that i'm considering running and i've got stock springs. I need to keep the spindles since i've already got those fit with the C5 brakes and i think they are a quality unit but right now i'm thinking i go as long as i can without notching the rear frame (which the backs almost at) however with the current setup the fronts a hair higher then the back. And i THINK its 2" spindles, 2" springs but might be 1" its been to long..

for the rear i really want to do a 4 link with coil overs, one of my buddies is going to be an engineer and wants to weigh the truck from a couple spots find center of gravity and somehow calculate brackets and heights etc so we'll see how crazy we get with it but at least i'll have the space to do whatever back there.. no fuel tank or lines etc.

 

[rentedmule]

Re: 2WD S10 setup for road racing

The control arms, shocks, and spindles are the same on the 2wd s-series and G-bodies as far as I know. The G-body spindle may be a bit different but I know that crowd is fond of swapping on the 2wd blazer spindles so they can upgrade to the blazer's dual piston brakes or do an easier 'vette brake swap. The G-body frame is wider though so steering components, frame braces, and swaybars aren't the same.

I think the Z85 option (towing package) factory coils are the stiffest but they'd need to be cut to give a reasonable ride height and they may be too stiff after that. I originally had those and when I swapped to ZQ8's it felt much softer. Some guys are using circle track coils and a spring jack to adjust ride height instead of coil overs. The parts are cheap and there's endless coil selection.

Check out protourings10.com. It's not a big site but there are a few serious suspension builds happening there and a few with link setups in the rear. There's lots of archived info on things like factory coil specs, swaybars, etc.

 

[brock1949]

Re: 2WD S10 setup for road racing

I also just noticed your running the vette wheels.. I love those but i was under the impression those only worked with the 4wd/AWD because of back spacing. Do they tuck into the wheel wells ok no trimming etc?

I was looking over at Protourings10 your right thats got some great info.

The circle track springs are interesting because i had those LCA that just have a flat steel 1/4 plate with a single tube welded to locate springs so i could easily modify it to take those springs. Do the circle track springs fit into the upper pockets?

 

[rentedmule]

Re: 2WD S10 setup for road racing

I run 2.5" spacers/adapters all around with 17x9.5" front with 265/40's and 18x10.5" rear with 295/35's. They fit fine on my truck but it's not low relative to most. I winter drive it (and winter auto-X it) so I have to leave enough room to clear snow tires on stock wheels. They're about flush with the fenders on the front and a hair inside on the rear. The clearance is close enough in the front that when I put the vette wheels on in the winter for dry pavement races they'll rub the mudflaps on most turns.

I can't remember if this pic is from before or after the 0.5" tall BJ drop so it may be a bit lower now.

I'll try to find the info on the circle track springs - you can buy them in the same dimensions as the stock coils to fit correctly in the spring pockets.

 

[brock1949]

Re: 2WD S10 setup for road racing

I called and talked to Mark st SC&C.. all i can say is wow. You almost need one of those court recorder people to write it all out so you can go back later and study it.

So highlights are, my spindles aren't in it for the long haul, my C5 conversion is going to kill me, the design is 50 + years old and terrible, lowering my truck did nothing to help body roll and the only thing that did help was the giant sway bars just so the suspension stop flexing it worked so poorly.

Not far off what i thought really, all the way down to the brake kit.

The good news is it doesn't seem like its terrible to fix it and he doesn't seem to think its a lost cause building a S10 for road racing for competition even. He did confirm my fears that basically my new rear link suspension is going to be wrong for one when its right for the other but adjustable stuff should help. Any time someone ends a call telling you that properly setup with enough power you should be able to run or pass a stock Z06 vette you can't be to upset finding out how much money you need to spend to get what you want.

Amazing information though i really didn't think anyone existed that would really know this much about setting up suspension for a road course. Again rentedmule thanks for taking the time had i not talked to you and Mark SC&C i would completly be headed in the wrong direction.

 

[rentedmule]

Re: 2WD S10 setup for road racing

No problem! If you're worried about the link setup you may also want to check out hotrods to hell's truck arm kit. It's not as sexy or technical as a 4-link but it's supposed to drive great and be a really good street/track compromise. I've never heard a bad thing about it on the pro-touring forums either.

http://www.hotrodstohell.net/truckarm/s_10_kit/truckarm_s10.htm

 

[brock1949]

Re: 2WD S10 setup for road racing

thats fairly awesome i didn't see any pricing but i'll probably give them a call this week and see what they have to say about my plans.

I think i figured out what my mystery lower control arms are appear to be DJM 3" drop lower control arms CA2331L-3. I'm really on the fence on how useful they are going to prove to be but i want to have it decided in the next week or two so if they aren't going to work i can get them sold and out of the bed of the truck, I must have moved them 10 times by this point but i got them for 50 bucks figured they were worth a shot and appear to be well built without a doubt stronger then the factory stamped.

I added a couple pictures of them on my picasa page if you or anyone else wanted to take a look and give me your thoughts on if they were DJM and what the general thoughts are on DJM.
picasaweb.google.com/carpenter.brock

I need to check what height spring i'm running now but i can't take the front down more than one more inch or it'll be to low for me. I'm thinking i've got 2" spindles and 1-2" springs. So if i could find a std length spring that the rates were ok then use the spindles and control arms i'm still looking at 5" drop, or i goto a std spindle, 3" drop lower control and if my beltech springs are 1" and a decent spring to run i could go that route.

Only thing i'm confused on is whats the best way to set the ride height... Springs, Spindles, lower control arms, which combination etc. I kinda asked Mark what combination really make the best handling setup and he started into telling me spindles 1" drop made a big improvement like the ATS spindles but then said past that it doesn't help then he said ride height didn't help that much but said S10's sit higher then G bodies etc and usually need some drop.

And last thing, whats the story with the tall spindles? Is this what the blazers run and do they yield any geometry gains? I've read a million mixed things

 

[1988Jimmy]

Re: 2WD S10 setup for road racing

www.speedwaymotors.com also offers a upper arm comparable to the UB arms.

http://www.speedwaymotors.com/IMCA-Approved-Spec-Stock-Car-Control-Arm,2120.html 42.99ea

http://www.speedwaymotors.com/Chrome-Moly-Upper-Control-Arm,4853.html 47.99ea

http://www.speedwaymotors.com/Chrome-Moly-Upper-Control-Arm,5584.html 54.99ea

I plan on running the Chrome-Moly uppers with steel crossshafts in mine when I do the tall upper/lower balljoint conversion.

You will want 2 right-hand arms if you place an order through them. They use an 8" arm on the right, 8.5" on the left in dirt track. Naturally you won't need the staggard left control arm since both sides are identical in daily applications.

 

[rentedmule]

Re: 2WD S10 setup for road racing

I'm not 100% positive on this but it was my understanding that the UB Machine UCAs that are specific for the tall balljoints have more caster built into them. They're not symmetrical like the speedway arms.

 

[1988Jimmy]

Re: 2WD S10 setup for road racing

This could possibly be true mule, I'm not positive about more caster being built into them. I just know (from a friend having a set on his bagged truck) that they are both identical.

 

[rentedmule]

Re: 2WD S10 setup for road racing

The speedway arms are also a good option because it seems like some people are having a hard time getting their hands on the UB Machine versions. The guy that did the initial design work was laid off and it seems there's some confusion there about the build specs.

 

[1988Jimmy]

Re: 2WD S10 setup for road racing

Well, it's good to know that there are other options out there for the time being.

 

[brock1949]

Re: 2WD S10 setup for road racing

Ya when i called UB machine he didn't seem to know anything about a specific arm for the S10 series etc but said he has a Gbody company constantly ordering a 8" upper and bets thats the correct one. He told me to find out what others ordered..

So are the factory uppers different side to side for caster? I'm starting to read more and more about caster angle playing a big part in these.

 

[rentedmule]

Re: 2WD S10 setup for road racing

Send a PM to dusterbd13 on s10forum or protourings10 - he's the one that helped with the design work so he should be able to give you the specs for the UB Machine arms. When I got mine they were only the 3rd set they'd made but I know at least 6 or 7 people have ordered them since then. It seems like something they should have kept on file but maybe Tony took that with him when he got laid off from there.