I'm contemplating using a gasser style axle on a project that will subject the front end to extreme off road duty (rally vehicle). There is a variety of hardware sold for this purpose and presumably those pieces work fine on street vehicles but what I'd like to have some opinion on is just how strong forged 37-41 spindles might be. I've seen countless pics of the typical wheelstanding behavior beloved of gasser fans everywhere and it's likely that a Speedway or a custom axle will take the stress of whalloping back to terra firma but will commonly available spindles survive such extreme behavior? Main reason I'm asking is that the intended use would greadly benefit from the much lighter weight of a 2'' straight axle but not at the expense of spindle strength. This approach would also make brake hardware selection much more flexible than, for instance, using an old 2wd Jeep DJ postal axle in front. What sayeth the assembled multitude?
Seriously look into dirt track (Sprint cars & Dirt Mods) axles and spindles as those are designed for abuse, stay away from street rod parts
There was just a thread on here about using 2wd Jeep Cherokee axles. Most said they were ugly and bulky. A few guy chimed in and said they were strong and they ran them on their off road projects.
Cherokee axles are undoubtedly strong enough but they may be too wide for the notional application. I can't seem to find a width for them online. A postal Jeep front axle will fit fine but converting to disc brakes is, from what I have been able to gather, on the difficult side. DJ axles, drum brakes and all, might be the easiest way to go since although they are hardly lightweight they do weigh less than, say, a Dana 30 with all the guts pulled. BCCHOPIT is likely to have valuable input on this.
As a former professional Rally Driver, I can't imagine building a Rally car with a straight axle. I would love to know what you are building .......
Hotroddon this is a notional build for the Peking to Paris rally where the more unlikely the vehicle the better the participants seem to like it. It's unlike most international vintage rallys in that the high speeds that "normal" rally vehicles can obtain are not really necessary but stoutness of drivetrain is at the forefront of considerations. This buildup would be a Jeep CJ6 which would ordinarily be fine as it came from the factory but there is no reason a RWD version would not work as well or even better since there is considerable pavement driving in addition to the massive punishment meted out by traversing the Gobi Desert. There is plenty of sand to deal with as well as some rocky terrain but the primary equipment destroyer is motoring smartly along the moon cratered landscape of northern China loaded up with gear. Thus it is helpful to reduce a vehicle's weight as much as practical, without compromising strength, in an attempt to keep the rugged course from pounding a vehicle into scrap metal. Converting a CJ6 to RWD would yank several hundred pounds off the vehicle and the 4WD aspect would not be much missed, especially on the paved legs. Sure the choice of vehicle is a little nutty but no more so than most of what ends up actually running the event.
Class 1 is single seater Class 2 would work a little better A trophy truck would be better yet, but it sounds like he might be bound by some "Vintage" class rules
He didnt say he has to carry a passenger-- trying to save weight Spent many hrs in the right-hand seat during the late 70's
The serious offroad/rally guys don't use a solid front end with 2wd. They sacrifice overall weight, and complexity, for reduced unsprung weight.
Some of the dirt guys used IH spindles. Strength and steering arm attachments are plusses. We raced a class 8 '78 ford and used 1 ton ford spindles and hubs with big GM rotors and calipers adapted. Twin I beam was the hot setup back then , class rules on suspension mods. have changed ,mucho !
On the Chevy Class 8's we use to build tubular A-arms for the front and then weld some stock sections (very little) to them because the rules stated "Stock arms, but may be strenthend with tubing"
The class rules, and the rules in general for that matter, are very much up to the discretion of the P2P organizers and they frown on vehicles with hardware too much out of line with the era of any specific car. For instance a 40 Ford with an independent front end and a 5 liter cammer or a Tri-five with a Heidts IRS and an alloy LS 7 would be right out. A 40 Ford with almost any flatty would be fine and a Tri-five with a mild 350 would likely be okay. Basically a lightly modified stock drivetrain in most all respects is what makes the grade. In any case I'm not at all sure that huge power would be of much use in an event that barely breaks an average speed of 35mph over 8000 miles of wildly varying and extremely punishing terrain. Plus I'd like to see someone run a trophy truck or a blown Group 5 car on the crap gas available in many of the seriously remote locations of the event. 8-1 compression or lower is recommended. In short the P2P is a very peculiar event even by the standards of "conventional" vintage rallying. This years entrants ranged from a 1917 LaFrance Touring car with chain drive to an Aussie 1973 Leyland P76 large sedan.
If you need any info about the rally give us a shout as we did the 1940's Ford this year that came 3rd. Cheers Jim [email protected]
Thanks a bunch bjj. Don't hesitate to point out anything I've gotten wrong about the nature of the event and the vehicles that participate in it. And oh yeah, curse those Fangio Coupes!
One other thing bjj. I notice on the 40 coupe's build page that what looks very much like 37-41 spindles were used. The original thrust of this thread was to ask if those would be strong enough for what the P2P had to dish out. It appears that you thought they would work okay. Did that turn out to be the case?
MGene they use screw-on snouts to accept 3/4 ton bearings new hubs with the hubs are used today check any circle track supplier.light weight is always a plus except bonneville
You want tough?? A lot of dirt-track modifieds still run '60's-vintage 3/4 or 1 ton International truck spindles due their strength. You can even get aftermarket 37 Ford-style "Wide-5" hubs with lots of different brake options to fit them. Mart3406 ===================
Mike bent 3 axles before he got the super heavy duty axle I built him. Before I sent him his new axle I had him send his spindle out for testing to see if they where cracked and they passed that was 2 years ago. He drags his bumper almost every time he brings it to the track. I think he wants his front tires to last for ever FYI his axle is made out of 2.5" X .312 wall moly. with my custom ends to make it all work the the ford spindles. Mike and I call it the dump truck axle...
The 2wd Cherokee axle is just like the Dana 30, just without the pumpkin. Imagine an axle with a tube that just keeps going, all the way to the other side. It is ~58" wms-wms, and can be narrowed easily.
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