I've always thought gassers were cool, but just watched Two Lane Blacktop and my interest is definitely peaked. I've been wondering how the straight axle affects the car. What are the benefits? How does it affect a real street car? Bad handling? After researching the movie cars I found out that they all had olds rears with 4.88 gears, but I can't find any info on olds rears. Why an olds rear? What years? I've been trying to figure out the defining characteristics of a gasser, but I'm a bit stumped. Is a straight axle a mandatory trait? Thanks, Rex
Straight front end is a defining characteristic as well as radiused rear fenders. 57 Olds rear ends are popular because of their larger ring gear. I forget but I think 9 1/4 or bigger. They can be made to handle very well on the street but they can also ride like a cement pad and slam the crap out of you. 4:88 gears is pretty steep on the street even with a 30 inch tire. I run a 4:10 under my 55 and a 29 inch tire and at 55mph, I'm turning about 3000rs. Hope that helps a litlle.
there were plenty of gas class cars without straight axles. the old guys here seems to remember more without than with.
Key points on gas class cars: 1. Full bodied, maximum four inch chop/channel/section. 2. Stock wheelbase. 3. Maximum 10% engine setback. 4. Suspension required at all four corners. These classes were (at least in the early years) "street" classes. As the level of competition escalated, the specifications (or at least the interpretation of them) got looser, and the cars became more purpose-built race cars. Keep in mind that the exact requirements changed almost every year. Straight axles were used to save weight, and sometimes to elevate the stance. Street applications vary widely; some handle ok, while some can only be described as scary. The Olds rear was used extensively in all kinds of drag cars. It was strong and widely available. The nine inch Ford design became dominant through the 70s.
What trans do you run, Rich? Got a link to pictures of your car? What are the differences between a good handling straight axle and a harsh one? I mean, if you were setting one up on a car to be driven regularly, could you be certain that the setup would be streetable? Would you guys still consider an olds rear to be a good choice or are there better (reasonably priced) options available? Sorry for all the questions, I appreciate the help.
Rexkarr, Just some comments as I've been thinking about this a lot lately. I had three '57 Olds rear ends at one time, but sold them all off. As I wanted street rigs I was finding it difficult to find street gears (I run 3.50 gears and a posi most of the time) for the Olds, race gears and spools are more available. Plus I kept running into lots of abandoned old Ford trucks with nine inch rears just waiting to be liberated and moved to my shop, so have standardized on that. Am building my first straight axle gasser now, but have helped others build up quite a few, and the usual issues of correct spring rate, shock specs, correct camber/caster/toe-in, good quality bushings in the spring ends, shackles set up properly, steering set up properly, no (or minimized anyway) bump steer, all if done correctly will give a decent ride and handling. Do some searching of the threads here, there is a lot of info you can learn from. I've been going through them lately refreshing a lot of ideas I haven't thought about lately, and want to make mine ride and handle well. I am starting with fairly stiff front springs, 6 leaf Posies, as I am going to run my blown Olds big block and it's heavy, will soften it up from there if it is too stiff. Read everything you can find though, it really helps clarify the issues you will need to consider. Good luck and let us know how it goes. 2loose Willy
I used the axle and springs from a 69 Dodge van under my Valiant and it drives as well as most pickup trucks. I think the longer springs make for a smoother ride.
www.gassermadness.com Everything you ever wanted to know about gassers. Cool vintage pics plus reader rides and for sale. Mine rides ok, like the old 60's vans. Streetable, yes.
So I read the link and the history of gassers, and found out that I have a gasser... circa 1958 rules it would run in the C/G class. I've been wanting to build a gasser for a couple of years now and I already have one... well me and everyone else who drives a street legal traditional hot rod...
Rex, I took and old 39 Studebaker that was built as a gasser back in the 60"s and made it street legal. The first thing to note is that it was made to go straight and fast. It took a bit of carefully driving it into corners to realize that this was no touring car. If I let off going into a turn,and then turned the wheel, and gently got back into the gas, it was just fine. If you didn't let off going in, it just wanted to plow forward.(Glad nothing was in the other lane) Those real narrow tires don't like to turn well at higher speeds. It was one of the most interesting car I ever drove on the street! Attached are some pictures of it way before I got it.
About the only info I can toss out has to do with cost of a straight axle... The used setups I have been seeing out there are 300-600 and will need fabbing/some new parts probably. If you have access to parts and do your own fabbing (shortening the axle, creating mounting tabs/brackets) great...but if you have to farm that out and buy a bunch of parts sometimes it is cheaper to just buy a hub to hub kit for around 1100 bucks. For used I have seen quite a few old vans/truck setups mentioned that can be used. But I have a question about a used setup to. What about a straight axle out of the 2wd postal jeeps. Have any of you ever used one of those?
Rex, I would have to say no, a straight axle is not mandatory.....I would remember that a gasser is utimatly a race car for the drag strip ( driven to the strip or trailered)....don't worry about cutting it up, making it lighter, and changing many things.....they were cheap cars that were made to go fast...keeping that in mind, creature comforts (air conditioning, power steeringh wern't part of the mix...sure, early cars had to have interiors, but they were lite. Modifications to the suspension were for the betterment of traction, the look, just was the by product....function over form...Now I am not saying make it ugly, just think of it as a race car first, then street, and I think you will be on the right track......have fun with the build, and hopefully we can line up some day....Don
the speedway kit hub to hub is right around 1100 bucks out the door. if you bought a used setup for 300-600 bucks as I have seen them on here and other places then had to pay to have it shortened, convert it to disc brakes if you so choose, get odds and ends for it you could easily be at the 1100 mark. I mean if there is a cheaper way without knowing how to do the fabbing yourself spill the beans.
I guess the $175 bucks I have into my '46 Dodge axle is pretty good then...most of that is rebuilding the brakes and bearings and steering...must suck to cough up that kinda cash to get an axle...
This helps a lot on keeping the cost down. <DT class=shade>Occupation </DT>Machinist/Fabricator I was talking for the non fabber that was paying to have stuff done. I can weld in floor pans other non life threatening stuff but with the straight axle setup you are talking life and death if you set it up wrong. as a person that does fabbing/machine work/hot rod work. Lets say I have a axle from a 55 chevy truck that is about 8 inches too wide for my falcon. I need it narrowed, leaf perches moved to the right area for the frame. Shackle mounts welded to my car and it set up so I do not have a ton of bump steer. you going to charge someone 175 bucks... Heck to have a welder cut/shorten/weld up an axle would run more then the 175 you have in yours. I am not trying to miss inform anybody. I am just trying to look out for someone that is not a fabber/machinist. And a EDIT: I did see some of your prices in an old thread. If you lived near me you would be hired on the stuff that I could not do. Very affordable prices!
MAS has better prices on their axles than Speedway, or use your HAMB Alliance discount through Riley Automotive...otherwise find a proper width axle and make bolt on spring mounts to mount to the frame...there are tons of ways to straight axle a car for less than the price of a catalog kit axle...
getting the steering right and add a little more castor than your normal hot rod setup...ran mine without any steering dampner or panhard bar , did a cross steering setup with hairpins and a cross spring. ran about 10 degrees of castor....got the axle from mas ....worked sweet and drove really nice on the expressway.....join gas/fx group for ideas and get the larry davis and don montgomery books....... the rest has been covered a BUNCH
If you keep an eye out, you can find deals. The speedway axles are kind of an easy way out, but not always the cheapest. I owned 3 complete axle setups. The willys axle I only gave 200 bucks for, the vintage superbell 37 chevy axle with mustang box was free, and the old truck axle out from under the 1965 straight-axle falcon at the junk yard $75. My Straight axle henry J does fine on the street. I have my front end in the air, but it handles ok because the suspension is stiff. It doesn't have much body roll or suspension travel, but that's the way I want it to be. It beats the shit out of me, but that's mostly because of the hard piecrust slicks and rear leaf springs with traction bars and stabilizer springs.
in the day, nothing was tougher than a 59-64 Pontiac/Olds diff. Today, they are very period correct and guess what, they are still TOUGH! IMHO, nothing is tougher except a Dana. Don't sweat the staight axle setup. Do it if you can, but they weren't all straight axle cars. If you are doing it only to be period correct, then you need the Pontiac/Olds diff. to make it all work together.
are you trying to save money or build a gasser, i have read all of this and it seems that it is a bout money? lots of posts about gassers, i have done a lot of them in the last few yrs, and they drive well if you do thime right, use new stuff and do it right no junk or it will dirve like junk have fun with it
It would help of you would post what kind of car you have or are considering building. If you are considering a straight axle (which is by no means mandatory), personally I would opt for a parallel leaf setup over a cross steer any day - less complicated and likely to handle and ride better - especially if street driven. If you choose to add a front clip to an existing chassis, you have the choice. My 0.02c
Wow, I didn't expect so many replies. Thanks for all the help everyone. I've been in love with tri fives for quite a while, so I'm hoping to find a '55 with the quarters already cut (I don't think I have the heart to cut nice quarters, lol.) If I'm lucky I might be able to get some seat time behind a straight axle car. That way I'd have a better idea of what its like. I've driven a '55 with a stock front suspension quite a bit and was surprised how well it handled. If I can get equal performance out of a straight axle, I guess there wouldn't be any negatives, except the extra cash spent. Although, I can do my own machining and fabrication, so hopefully the cost won't be to high. But I should say, that this car will be my primary tansportation through out the warm months. Would any of you want to drive your solid axle that much? Thanks Rex
i drove mine a couple days a week when i had it.....the cage was more of a pain than the straight axle deal....it was a real fun car to drive....miss it
I installed this narrowed 65 Chevy Van axle set up in my Chevy II back in the mid 70's. It handles just fine, runs straight as a string on the highway.
...I think you mean "cross spring" (transverse)setup, not "cross steer"....cross steering setups can be used with transverse spring or parallel leafs; cross steering setups are better and cause less bumpsteer if set up correctly.
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