Can a straight axle be made to handle well? Im talking about numbers on a skid pad or G test. I know the MG's used them with tall wheels and a low c/g. Im asking this in reference to a fenderless truck I'm aquiring parts for and would like to do it once [LOL]. Here is the basic formula 106 to 110'' wheelbase, paralell leaf rear with anti roll bar,motor will be a sm/ block Ford or 472 Cad. I have both. Questions or comments appreciated.
Several years ago Street Rodder did a comparison of 2 similarly built 32 roadsters, except one was IFS and the other had a straight axle...the results were surprising - the straight axle car was no slouch! EDIT - here's the link. http://www.streetrodderweb.com/features/0402sr_performance_evaluation/index.html
Thanks. The only ifs design I like is the Indy rocker style, and trying to figure the geomentry is mentaly taxing for me. Maybe on another project.
Looked at the link and found good info there. Im not knocking sprint cars, but I might want to turn right at a salom course for fun.
Come to Nashville Goodguys this weekend and I will take you for a ride. In order of importance DRIVER! A ****ty driver will look stupid in a new GT3 TIRES! 10 million dollar suspension will not work with ****ty tires WEIGHT! Lighter is faster, every time. That's why they have minimum weights, skip the Caddy motor SHOCKS! Shocks are the single most important part of your suspension, spend money here and you will be rewarded with better ride quality and superior handling. Finally, suspension design. An axle can work pretty well. The faster you go the larger the difference between an axle and an IFS are. I don't know what your plans are for the car but you mentioned slalom, so I will ***ume autocross. In that case you can be very happy with the axle. The hardest part is turning it quickly and getting enough turning radius with wider tires. If you are looking at skinny tires, like excelsiors or even vintage dunlops, watch the diamter in the front as that will affect your turning radius as well. A sprint car cowl steering setup can be made to work but the drag link may cause problems with turning radius again. I went through a bunch of Vega boxes with that Jeep double eyed tie rod end and that was okay but it always turned one way faster than the other. I finally went to a 600 series power box from DSE, 12.7:1 and straightened out the geometry.....much better. Hairpins in the front are fine, you can use split wishbones but make sure you get your alignment right as there is no adjustment with wishbones. Transverse leaf is good, too. Panhard bar is a must in the front and so is a anti ROLL bar. The transverse leaf doesn't offer much in the way of roll resistance so the ARB helps immensely. Again, depending on tires, you may want some negative camber. My 235/40-17s are happy at 1.6* negative. I bend the axle in a press and set KPI at 10* and the wieght of the car gets me the other 1/2*. I would advise against the leaf springs in the rear. Give some thought to the Pete&Jakes/So-Cal ladder bar setup with coilovers. I ran this with success until I went to the 3 link the that is in the car now. It will never be a corvette but just because you want an axle doesn't mean it has to handle poorly. I don't have any skid pad numbers but I ran within a half a second of the fast cars at Charlotte GG last fall, and I drove there and back. Just about drove the tire off the rim here....
Forgot the pic.... I know its not super trad the way it looks right now, but remember tires are important.....and they unbolt. I can swap to the steelies and hubcaps in a 1/2 hour and aside from the brakes everything is the way it should be....all the ugly is hidden underneath.
I auto cross my 32 sometimes, not good guys but a longer SCCA course. I think it handles pretty well considering. Tires and shocks make all the difference. I do not have a anti-roll bar but body roll on my roadster is not really that bad. I have tried both and I do feel triangulated four bar rears work better than ladder bars for the twisties. The tires in the pictures are not ideal. To run similar times with amateurs in porches and vettes with a straight axle is so worth it!
On a smooth surface a straight axle can do very well. It's irregular surfaces where a good independent suspension can do better.
This is good info. I will concentrate on these needed parts. If I make it to Goodguys I will take you up on it ,dontlift. I am doing my research now and listening to avoid issue later.Everyone keep replying.
Yeah, bigger scca courses are way more fun http://www.ridetech.com/garage/2010/05/donny-freise’s-32-ford-roadster/ I will disagree with the triangulated four link vs ladder bar thing. It may have felt better because of the higher roll center with the tri link but the ladder bars are fast.....its a truck arm but lighter and properly setup they hook up and go. I don't use the roll bars to control body roll, I really don't worry about body roll as it has no effect on the suspension geometry, so who cares. I use the roll bar to transfer weight to the outside tire. Without it the car just rolls on the spring and doesn't really load the tire at all. Hope to see you in Nashville! Donny
If you want to see a straight axle leaf spring 32 coupe that handles watch this video - Jim Busby and Rick Knoop's car. There is a lot on here with the Jaguar IMSA car they restored, but it is worth watching - this 32 scoots! http://www.youtube.com/watch?v=X7RuLXEOnYU
Busby's car hauls ***! Top quality fab work on that car as well. If anyone recognizes the tires on that car please post, I have been trying to figure out what they are....Dunlops? There was a picture of that car floating around where it had broke a spindle, sheared the pin right off.....I'll see if I can find it.
It does use the reproduction Dunlop Sports racing tires. I have known Rick Knoop for many years, from back when I ran in IMSA in 85. I was at El Toro when they were testing that thing through the Slalom and Skid pad. Not only does it work very well, that motor is just a joy to listen to.
Do the dunlops work? If I remember they are über expensive but they sure do look better than what I am currently running. I have been thinking about a more hamb friendly wheel and tire package and these may be the answer. To the op, sorry for the high jack, I hope this is all usefull info. To
Solid axle can work well if you do not expect too much. Limited travel means it works best on smooth roads or race tracks. Not a good ride on rough roads. Cunningham race cars did very well at LeMans with a straight axle front end in the early fifties. They actually changed from a modified 49 Ford IFS to a straight axle in 54. This was a 175 MPH sports car. Frank Kurtis also did well with solid axles and torsion bar suspension. Today of course everything is IFS which no doubt is better but that does not mean the beam axle setup can't work well if set up right.
Then I guess that NO FORD or any hot rod on here ever had a Straight Axle as even model T axles had the spindle centerline higher than the beam itself.
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