djsanchez2

iTrader: (14)

Ok fellas. I have not seen too much info on open road racing suspension set ups. I am interested in doing this next year and thought i would take this year to prep. My car is a M6 SS, current mods:

Long T/A w/ tunnel reloc bracket
SFC's
adj. PHB
adj. LCA's & Reloc. brackets
KYB AGX shocks
Stock springs (looking at Strano or 1LE springs )
Stock F&R sways poly endlinks & bushings

And i would also like to know about safety equipment.

So far I'm thinking:
6pt. cage
5pt. harnesses

Viper

iTrader: (6)

Dump the shocks, get Koni's. Dump the relo brackets for road race.

What ends are on the PHB and LCA's?

If you're sticking with the stock springs, the stock bars are OK. But you'd be happier with a 35mm bar, 21mm rear.

If you're going Sam's springs, I highly recommend 35/21 bars.

6 point harness, helmet, driving school, seat time.

Tires?

Stock brakes? If so you may want to at least upgrade to Brembo blanks and better pads, and look into front brake cooling ducts.

Finally spend some time on www.frrax.com, you'll learn a ton more than here.

djsanchez2

iTrader: (14)

Thought about switching to the Koni's, but i don't have the funds for that and everything else right now. The PHB and LCA's are UMI Poly/rod. The reloc brackets are bolt-on so easily ditched.

Brakes- Hawk HPS, Edge slotted & steel lines.

The bars, i thought about it, but would they be too much?

Tires, not quite sure about yet. But it will be my first event i will have to be in the lowest speed class. I know a few guys that have been doing it for over a decade, but they don't really know anything about the newer chassis' So anything that needs to be changed WILL be changed for the following year.

Another question is offset wheels? Good idea, I have 17x9.5/11? Or should i get a set of stock SS wheels? all 9.5 ?

Viper

iTrader: (6)

For road race get all 4 wheels the same. For tires use street tires if money is an issue and just take your time, don't overdrive it. Nittos are a great alternative (NT-01 or 555rII's) as you can drive on the street with them to and after an event. I did several events on HPS pads, they worked fine for me. I don't think the bars are too much at all.

djsanchez2

iTrader: (14)

That's the plan lol. I'm not expecting to be able to go all gung ho and run 200 mph the first event out. Hell no!!! I get overly excited at 150mph as it is.

If i went with a nitto, i'm leaning toward the NT-01.

As for the shocks I just got them brand new, and installed last week. So i'm sure it won't be too much of an issue to sell them for most of the $$ back to help with the Koni's.

I was kind of afraid to go with huge f&r sways, i wasn't sure if it would make the car react to steering input too harshly at speed.

Oh and as for the reloc. brackets, if i'm lowering the car on Strano srpings/konis later on, Should i not keep them to correct the LCA angle?

Viper

iTrader: (6)

No, not for road race. The stock location is fine when lowering. Again, the bars were not too harsh at speed. And selling the shocks for koni's will be the biggest/best thing you do.

cookba

iTrader: (10)

this is all good info cause i want to eventually do this too. but im having a hard time understanding the pro's and cons of using relocation brackets for the TA and LCA.

djsanchez2

iTrader: (14)

Long arm-
Con: Possible tail shaft breakage issues, (reloc. addresses this issue.)
Pro: retains stock location. Softer on hard launches from what i've heard form the drag guys.

Short arm:
Pro: better instant center
Con: Possible rear wheel hop under hard braking

Viper

iTrader: (6)

As far as LCA, you want a downward slope from the body to the axle for drag racing so you get bite coming out of the hole. But you want the opposite when doing twisties; an upward slope from the body to the axle. To much of a downward slope makes the rearend VERY squirrely at high speeds ( turning ).

z28bryan

iTrader: (7)

How would stock springs make you feel at those high speeds and transferring weight? I would think you would want at least around a Strano springrate. I haven't road raced yet... but I have tried some higher speed autox events with very far spaced gates. On stock springs I kind of felt like I had to focus a bit on easing the car from one bumpstop to another so my rear end didn't instantly break free and lose control.

It is quite a rush though when you are doing that

zlover129

iTrader: (10)

I had never thought of this, i had put the Relocation brackets on my car and it did help with straight line traction a lot...but if it did start to slide it immediately wanted to kick out. Also you think that is enough rear bar on that 35/21?? I have some pretty evident understeer at the limit in my car and im running 32/21 ...i also do need camber up front pretty bad as im sure its set to maybe .5* max. That and i may need to play with the valving on my front shocks. Is it more front compression that will counteract understeer or rebound??

98_1LE

iTrader: (17)

I have open road raced my T/A a couple times, and like how it handles at speed.

Highlights are:
Koni single adjustable shocks
LG Motorsports G2 springs
Strano 35mm front and 22mm rear hollow sway bars
LGM aluminum PHB and LCA's with aluminum rod ends

My car does not have relocation brackets.

On an LS1 F-body in otherwise good condition, all you would really need to start open road racing (you will be limited to 140 mph tech or max speed as a newbie) is harnesses and an alignment. Of course a roll bar is a very good idea.

As you go faster cooling becomes an issue, including the trans and diff. I use an AAM/SLP diff cover that provides some cooling, as do many others running a 168 mph tech (which is where I run).

Alignment for an open road race fourthgen F-body should be the following IMO:
0 toe
-.4º camber
max out positive caster and make it equal per side.

z28bryan

iTrader: (7)

You definitely could use a bigger front bar. You probably already know, but the bigger bar preventing body roll also prevents the wheel from rolling, meaning more tire contact with the pavement. 0.5 degrees negative camber also doesn't help you too much. I ran that for a long time and I got lots of understeer even on 315 front wheels. When I went to -1.5 degrees it was like a night and day difference. I would say the bigger front bar and the extra 1 degree of camber will be quite noticeable for you.

If you crank up the rebound real high, then the car will stay lower longer. When the front tires are compressed then you gain more negative camber. I've heard some of the autox drivers talking about doing this in F-Stock since you need to use stock springs, though I don't know the cons of doing this. I'm sure there is some since you have less suspension travel right after a turn.

Viper

iTrader: (6)

I agree, the -1.5 is night and day.

zlover129

iTrader: (10)

yea, i've been planning on getting bigger bars when i get a chance to, at the moment i have literally $30 in my 32/21. And when i first got my alignment i wasn't present so they set it pretty close to 0. What about a little bit of toe in? I was thinking about trying that as well. I'll go ahead and see how taking the relocation brackets off works out. I'd eventually like to buy a 24mm rear sway bar from a 3rd gen for cheap and throw that on there and add some camber and see how that works too.

As for my shocks and springs, im on stock springs right now, i'd like to add a bit more spring rate and then adjust the shocks accordingly and see how that works out as well, i think with camber, tweaks to the shocks and springs, and my bars then i'll be very happy. Hell i have trouble taking it to its limits now without scaring myself, only certain roads im willing to throw it into a corner and dance on that edge.

z28bryan

iTrader: (7)

Since you have a solid rear axle, you don't have any camber, caster, toe settings in the rear.

Also the 21 is generally a good matchup for a 35mm front. Either that or a 22 hollow Strano bar. Anything bigger will induce more oversteer. 35mm front and 21/22mm rear is a well proven combo by many who have raced the car.

If you are road racing and still using the lower hole on the relo brackets, then try putting them back in the upper hole. The geometry of the LCA's when lower at the axle can cause turn induced oversteer, aka your axle points slightly to the direction opposite that you are turning.

zlover129

iTrader: (10)

Right, the adjustment in the rear i knew of, i've heard of several putting rear camber in but they were just pure track cars and that is a completely different discussion. I was talking about front toe, but again just a guess. And to be completely honest, i'd much rather error on the side of oversteer then understeer, understeer is scary as **** atleast oversteer i can do things to correct.

Do you think the changing of the LCA's will promote wheel hop under hard acceleration? Biggest thing i need to buy next is really a trq arm

hpjunky98

iTrader: (3)

Good explanation of Rollsteer

Not going to notice it DDing, but its definitely going to be an issue while open road racing at high speed. You want all the stability you can get.

If your camber adjustments don’t compensate for your understeer and you don't want to switch bars, you can always try to increase transitional oversteer by slowly increasing front compression and rear rebound.

Do the camber adjustments first, and leave toe neutral at 0 for a combo of high speed runs and corners.

hpjunky98

iTrader: (3)

Must have had IRS setups then because your not going to get any adjustment out of a solid rear.

Mojave

iTrader: (4)

You can camber a solid axle; you just need to use the 'hot' wrench (aka torch).