Ok, now if you havent figured that im on a quest for handling and hooking at the strip, i have yet another question. I read that the Guldstrand mod more effectively uses the coil spring so you could typically run a softer spring than with the stock geometry and get good handleing. I was thinking that since the moroso coils are made for greater weight transfer(240# springs) that they would help provide the traction i was looking for while the guldstrand mod would aid in cornering. Im considering using the HAL 12 way adjustable shocks with this combo. Now am i completely wrong in my assumptions. Im obviosly not going to get road racing type handleing, but i thought what i lose in spring rate i could make up for with shock adjustments.

The Guldstrand mod raises the front roll center, which stiffens the front end in a cornering mode only. It makes no change in acceleration and only minor in braking due to anti-dive changes. Anti-dive is reduced on the guldstrand mod because the front bolt is lowered more than the rear bolt.

The slightly reduced anti dive of the Guldstrand mod would make the car dive a little more than stock under braking. (that's a whole different subject)

When you bring the roll center closer to the center of mass in the front of the car, more weight is transfered lateraly (without creating as much roll) when cornering.

The books talk about it as a "lever arm" The center of mass has less leverage over the roll center than before the mod. When that happens the cars roll "torque" is inversly proportional to the lever arm length.

So, a shorter lever arm transfers weight in cornering more directly to the front tires, without generating as much roll force to the chassis.

A long lever arm (non Guldstrand) generates more cornering roll because the center of mass has more leverage over the chassis.

If the front roll center were raised up to the center of mass, the car would not roll in cornering even if the swaybar and springs were 10% of stock rate.
If the roll center were higher than the center of mass, the car would lean the other way!

The cornering forces are resisted by the springs and swaybar together. If the roll center were raised way up, the sway bar would have almost no effect on handling and you would not be able to tune the handling balance front to rear.
The front end will act stiffer in roll only, and the springs, swaybar and shocks will see less load. The cornering forces still cause weight transfer, but the suspension get's bypassed in part and has less to do with absorbing cornering shocks.
The tires will break loose easier, the car more twitchy.
I'm talking about an extreme case above. The Guldstrand mod just moves a little in that direction, not to a point where it's harmful.

It does affect the tuning of the cars handling.
Chicane67 stated that a 1" swaybar is plenty if you have the Guldstrand mod done.
If you had a bigger bar along with the Guldstrand mod, the car would probably understeer and might be too stiff in roll to the point where the tires would break loose more easily if even a small bump were encountered while cornering.

I wouldn't go softer than stock on a street car.
I think chicane67 will have some very useful comments on how to get off the line traction for your car.

It would help if you posted here what equipment, springs, shocks, engine/HP, and trans, you have now.
Any traction bars, single leaf or multi leaf?
David



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Check my web page for First Gen Camaro suspension info:
David's Motorsports page (http://ourworld.compuserve.com/homepages/David_Pozzi/)
First Gen Suspension Page (http://ourworld.compuserve.com/homepages/David_Pozzi/first_gen_suspension.htm)
67 RS 327
69 Camaro Vintage Racer
65 Lola T-70 Can Am Vintage Racer

By the info ive received from past posts, i am going to go with cal-tracs tractin bars, multileaf rear springs,eventually a blown 383 small block,t-56 or tremec 5 speed, fiberglass hood, cowl panel and valence panel. Like i said in the first part, i am trying to see what the feasability of the moroso coils are when combined with an adjustable shock such as the hal promastar and the guldstrand mod.

[This message has been edited by jvolk81 (edited 01-19-2001).]

If you get a properly designed rear spring, you might not need the traction bars and would still get a good launch.

The chrysler drag cars were very well developed in this area. They needed no add on traction device as they had the proper rear springs.
The company that developed these springs is designing them and selling them for all cars. I saw a story on it a while back.

chicane 67 knows how to do it too.

I guess it's my autocross and road race background that makes me shy away from the traction bars. They will usually hurt the handling. and are not needed if you have the right rear spring setup.
David

------------------
Check my web page for First Gen Camaro suspension info:
David's Motorsports page (http://ourworld.compuserve.com/homepages/David_Pozzi/)
First Gen Suspension Page (http://ourworld.compuserve.com/homepages/David_Pozzi/first_gen_suspension.htm)
67 RS 327
69 Camaro Vintage Racer
65 Lola T-70 Can Am Vintage Racer