Anybody slowing down from 150+ mph very quickly??

[HAULNSS]

Originally Posted by fatlife

^^^^^^^
great post and very well spoken. Oh and by the way, you won't be "racing" anyone but yourself. Remember that racing is totally differnet than an open track day. I know its hard to say driving at the track or something, but if you go to the trackday and talk about racing people are gonna look at you funny

I agree, there are a lot of good posts and tons of good info. The good thing about open track versus 'race days? Our open track days are considered 'driving schools' and most insurance companies will still cover the car. If it is timed or competetive, insurance is usually null and void.

They might look at him funny anyway......

Randy

[Blown353]

Oh, and start shopping for a good extinguisher just in case.

Don't get the standard powdered type, the powder is HIGHLY corrosive to aluminum... especially when you try and rinse it off afterwards.

Although if there's one thing Murphy taught me it's that your extinguisher never seems to be big enough...

If 1 is good, 2 are better, although a in-car suppression system AND a supplemental hand extinguisher is best. No sense in filling your interior with junk unless you absolutely have to!

[nitrorocket]

The rear suspension is good to go, except for sway bar selection. The front is stock except for the poly bushings. I notice a lot of understeer with the setup I have now in high speed sweepers. I thought B body spindles helped camber and you could get bumpsteer spacers??

[Teetoe_Jones]

Originally Posted by nitrorocket

The rear suspension is good to go, except for sway bar selection. The front is stock except for the poly bushings. I notice a lot of understeer with the setup I have now in high speed sweepers. I thought B body spindles helped camber and you could get bumpsteer spacers??

The camber gain is nice on the B body spindles, but the bumpsteer spacers don't work properly, as the spacers put the tie rod lower, and it needs to go higher. The turning radius also sucks on the b body spindle.
Best option is the Stage 2 SC&C kit, or our AFX tall spindles with steering arms. With our tall AFX spindle, you get all the camber gain you could ever want, your turning radius doesn't get effected, track width remains the same, and our bumpsteer is the best in the industry. You want to go fast on the road course, and have a C5 brake package, then we are your E ticket.

Tyler

[fatlife]

Originally Posted by HAULNSS

I agree, there are a lot of good posts and tons of good info.
Randy

Yeah this is a great thread, not only do we get to give great advice, we can stroke our egos at the same time! ...............

[Blown353]

Originally Posted by nitrorocket

The rear suspension is good to go, except for sway bar selection. The front is stock except for the poly bushings. I notice a lot of understeer with the setup I have now in high speed sweepers. I thought B body spindles helped camber and you could get bumpsteer spacers??

With springs in the weight ranges I suggested a rear sway bar should not be required at except as a tuning aid to dial in a little more oversteer (aka: driver preference.) I run no rear bar and the rear drifts ever so slightly with my setup which is exactly what I wanted.

Given the stock way of mounting a rear sway bar to an A-body the swaybar effectiveness is marginal at best which is why I prefer to tune the rear with springs rather than a bar. If it comes down to needing a rear bar a MUCH better way to do it would be to retrofit a 3rd gen F-body sway bar setup on the car, where the bar swivels on bushings attached to the axle tube then there are hard uplinks going to the frame.

My setup is as follows:

Front: B-body spindles, alignment specs of +5.5 caster / -1.0 camber / 0 toe, 1.125" sway bar, 750# springs (going to 900 or 950# when I change the spindles.) 255/45/17 tires on 9.5" wheels. The car does pull a little bit to the right on the street because I have no cross caster to compensate for road crown. Doesn't bug me, don't have any cross camber or caster in my daily driver either.

Rear: GW TBC-4 lowers, Edelbrock uppers with rubber in the rear end ears, Hypercoil 175# springs. 285/40 tires on 11" wheels.

Shocks all around are Edelbrock IAS which have better rebound control than most in the price range, but still aren't ideal. I am looking at picking up some single adjustable Varishocks from a friend who is a WD for them.

Given the weight of an A-body I chose tires that would end up being installed on the widest wheels recommended by the mfg to minimize sidewall deflection/squirm. I may try a 275/40 & 315/35 setup next time to see if the additional rubber (theoretically more overall grip) outweighs negatives of additional sidewall squirm (theoretically less turn-in feel) compared to the current setup.

As far as the stock front suspension... no wonder you're pushing! The stock suspension has terrible camber gain properties-- in fact, it's reversed! It goes positive on compression. Bump steer is so-so and the roll center is too low. It has everything designed in backwards to what you want in a performance app, but is perfectly safe for grandma (i.e. it pushes really, really badly!)

B-body spindles help raise the roll center a bit and change the FVSA to give better camber gain but they also slow the steering ratio, screw up ackermann, and dramatically increase the bump steer. For a long time it was the "hot ticket" simply because there were no other alternatives short of custom, but now there are lots better options... SC&C stage 2 with stock spindles, ATS spindles, or the "Denny" setup with the Coleman spindles, although with the Colemans and their pin drop that setup is best utilized on very low ride heights. I believe the Coleman setup is better than the AFX setup geometry wise by a hair (and I mean a tiny, tiny bit) but for more "street friendly" ride heights the AFX has the advantage because it puts the control arms in a more favorable spot for lateral scrub because the AFX spindles have less pin drop. If used at the more street friendly ride height the Coleman setup puts the control arms at a slightly less favorable angle. If you don't mind your front X-member about 2.5" off the pavement with 25.7" tall tires then the Coleman setup is pretty badass... at least with stock control arm locations and lengths. Getting much better than the AFX or Coleman setup would likely require custom control arms and revised mounting locations.

[chicane]

Originally Posted by nitrorocket

Curious of any brake issues anyone has hauling there heavy cars down from 100-150 mph time and time again on the road course. Any recomendations on rotors, pads, or calipers?

Sure.

[nitrorocket]

Hmm, Right now I am looking at Hal adjustables in all 4 corners, HR parts rear bar, 500lb springs in front with 150's in rear(I need to tune with a roll bar to have a little more weight transfer, I have alot of power to hook), C5 front discs and calipers. Not sure on tires yet, I have to see what brands are available in my sizes.
I just need to research front suspension geometry and make some front control arms. Anyone try the longer ball joints to correct the negative camber problem?? I have not heard anything negative.
This stuff should get me going enough to make the car work pretty well I think. I also need to tighten up my steering a little, I can steer closk to lock with my pinky finger! It is so easy to steer that If I wasn't more used to the car, it could be dangerous. The wife has been complaining when she tries to accelerate or corner quick, it is to easy to over compensate... kind of dangerous for her. Anyone know of any tricks to lower the pressure in the ls1 steering pump??

Great input!

[fatlife]

Great idea, on the steering gear, that alone will make a huge differnec. Your suspension setup idea sounds good for the street/strip but not all that great for the track. However you don't have to have the super track suspension just to go. But I wouldn't be thinking about trying to go super fast like you have with that setup.

[Blown353]

Originally Posted by nitrorocket

Hmm, Right now I am looking at Hal adjustables in all 4 corners, HR parts rear bar, 500lb springs in front with 150's in rear(I need to tune with a roll bar to have a little more weight transfer, I have alot of power to hook), C5 front discs and calipers. Not sure on tires yet, I have to see what brands are available in my sizes.
I just need to research front suspension geometry and make some front control arms. Anyone try the longer ball joints to correct the negative camber problem?? I have not heard anything negative.
This stuff should get me going enough to make the car work pretty well I think. I also need to tighten up my steering a little, I can steer closk to lock with my pinky finger! It is so easy to steer that If I wasn't more used to the car, it could be dangerous. The wife has been complaining when she tries to accelerate or corner quick, it is to easy to over compensate... kind of dangerous for her. Anyone know of any tricks to lower the pressure in the ls1 steering pump??

Great input!

OK... here are some suggestions:

The HAL/QA1 shocks are old-news. For a resonably priced adjustable shock there is no better option going right now than Varishocks IMO and also based upon track experience with a friend who runs them on a couple of his Mustangs that see HARD track time. The Varishocks hold damping rates much better and the "street" versions have much better and more durable bushings compared to QA1s. Marcus at SC&C feels the same way about them too. Same price as QA1's, too. There are many better choices out there but they all come with a bigger pricetag.

No offense but your car is gonna wallow like a pig with those softy springs and I know this from experience, I used to run springs with nearly identical rates as what you suggested (550/150) and tried all different bar combinations up to a max of 1.5" front / 1.125" rear... all of them sucked IMO. Feel free to try sticking some massive bars on there to compensate for it but having done the soft spring/big bar and then the big spring/soft bar approach on my car the big spring/soft bar approach works better and is much more predictable. (If you do try the big bar approach make sure you reinforce the mounts in the front frame for the bar before that big bar tears the bolts through the tapped holes in the frame.) Counting on the springs to do your weight transfer isn't the best way, better way is through suspension geometry. This isn't the drag strip so no need for 90/10 shocks and softie springs! Swapping springs on these cars is a piece of cake anyways.

No need (or reason IMO) to make new front control arms unless you want to increase their length and run more backspace on the front wheels for less scrub radius, but unless you move the spring pocket outwards too the longer arms will have a undesireable change in the motion ratio. The stock arms with plate reinforcements for the LBJ will be plenty good, or go to aftermarket (I like GW and del-a-lums.) Marcus's kit with the tall BJ's does an excellent job with the geometry and you can still use your stock spindle.

As far as your steering... short of custom, I'm still in love with my DSE 600 series box. Superb feel with u-joints on the steering shaft and all fresh steering bits. The Lee Mfg / ATS box would be a fantastic choice too.