Rack and pinion steering.

[B.R.E.Demon]

70 dart. Doing a pro-stock tribute car

Message me privately I will work up some of the notes from them this weekend and get them over to you so if you wanna try doing it yourself, I will say I recommend doing it with a tubular cross member to start with. It’s a lot easier.

 

[HPP]

For a competition only car, certain design parameters can be utilized that may not necessarily transfer well to a street going car. No ackerman, no anti-dive, more or less aggressive camber gain, alternate instant centers, higher or lower roll center location, and more or less scrub radius are all fair game when designing race suspension and steering systems. In a drag car, a number of these can be compromised for straight line performance. in a road race system, some of these parameters need to be enhanced, and for oval, a completely asymmetrical set-up that turns itself will be most productive.

It all varies based on need and is not a case of a one size fits all approach that most of our more knowledgeable and experienced members understand. However, if a rack is simply swapped in for convenience or light weight without understanding the impact of the changes, then unintended results can come about. Like someone else mentioned, Unisteer R&P conversions are a good example an popular idea done in a questionable manner that created more problems than it solved.

 

[gregsdart]

For a competition only car, certain design parameters can be utilized that may not necessarily transfer well to a street going car. No ackerman, no anti-dive, more or less aggressive camber gain, alternate instant centers, higher or lower roll center location, and more or less scrub radius are all fair game when designing race suspension and steering systems. In a drag car, a number of these can be compromised for straight line performance. in a road race system, some of these parameters need to be enhanced, and for oval, a completely asymmetrical set-up that turns itself will be most productive.

It all varies based on need and is not a case of a one size fits all approach that most of our more knowledgeable and experienced members understand. However, if a rack is simply swapped in for convenience or light weight without understanding the impact of the changes, then unintended results can come about. Like someone else mentioned, Unisteer R&P conversions are a good example an popular idea done in a questionable manner that created more problems than it solved.

A well thought out article on drag only applications would be it's own book. Anyone written it up?
As for me i feel i got lucky, pretty much copied the factory 65 dart front suspension but with zero ackerman, coilovers, and used stock A arms, but eventually custom making upper A arms that allowed more caster.

 

[HPP]

Doorslammers by Dave Morgan might be such a book. Its been a long time since I looked through it and I know there is a chapter on front suspension, but I forget how in depth it goes on the subject since the book covers many aspects of drag race vehicles with doors.

There is also the old stand-by DC or MP Chassis Book. While many of its recommendations tend to be on the conservative side of modifications, it does go into some good explanations and ways to check and verify front and rear suspension along with explaining why the factory set-ups are configured the way they are. The companion Oval Track Modifications is also good and gives additional data points about suspension set-ups that can be applied to right and left turns.

 

[weedburner]

I used to design anti-ackerman into my dirt latemodel front geometry.

True ackerman typically aligns the front/rear wheels to a common center point, which makes less friction as a car rolls thru the corner. But when a car corners with the tail hung out, true ackerman will have the angles of the front tires fighting each other thru the corners, causing drag in the front that slows the car and makes it more likely to spin out. To keep the front tires pointed in the right direction with the tail hung out, they need to be aligned to a point in the infield, as the rear will be operating at a big slip angle.

Anti-ackerman will increase casual driving tire wear and reduce mpg, but it can make the car more drivable when it gets out of shape. Zero ackerman is basically a compromise between the two.

Grant

 

[gregsdart]

Not being used to the tems used in racing circles, my use of "zero ackerman" was meant to convey my front tires stay perfectly parallel at all points of steering travel. Thanks to all who have contributed here!

 

[MOPARMAGA]

Not being used to the tems used in racing circles, my use of "zero ackerman" was meant to convey my front tires stay perfectly parallel at all points of steering travel. Thanks to all who have contributed here!

Zero Ackerman does sound like the safest for going fast in a straight line. Thanks Greg