A friend decided that he really wanted a straight axle under his 55 Chevy. It already had radius'd wheel wells and had been raced years back. So he yanked the motor and trans and towed it over. We put it on jack stands to get an idea of how he wanted it to sit. Looks about right. We lifted off the front clip to expose the victim. You gotta love the firewall patch. Out came the saws all and I told Greg to whack it off! The scrap guys gonna love it today. No turning back now. Clean up the rails a little and lets see what happens next.
We took some 2 X 3 tubing and tapered it down to match the 2" front tube, welded it together and slip it into the original frame. We set the front clip back on and jacked the new frame rails around until everything seemed copacetic. With the clip back off, we could see that we were going to have to reshape the original frame a bit to match. We sliced, pie cut and bent the original rails until everything lined up and then I started welding. Next came the springs. Using the axle centerline that we had measured before cutting off the old front end, we determined where the springs need to go. We actually pushed the wheels about an inch further forward because we thought it looked cooler. Now came time for the steering box. He is reusing the original, so we made tube that went through the frame and welded them in place. We jacked the axle into place, set the caster, welded the perches and ....
Bolted the spindles, steering arms and brakes in place. Had to watch the glare off Greg's head in the camera though. We bolted on some roller wheels and a temporary tie rod to see how she looks. Back went on the front clip and Larry will drag her back home to install the motor and terrorize children, old ladies and small dogs. Looks pretty good for 2 days work don't cha think?
The front axle seems too narrow.is it suppost to be that way,especially with the skinnies going back on the front? But this was a kick ass read man. Thanks for the step by step.Straight axle gassers are my bag on here!
That's the width Larry wanted. The skinnies that he is running actually have less back space then the all too familiar red rollers so they will stick out a little more, plus he just felt that it looked more era correct. I might have gone a little wider but, hey, it's his car
what did you set the caster at? and another question, how do you know what angle to set the front shackle at?
Set the caster at 6 degrees. We set the shackles so they would be approx verticle under the weight of the completed front end.
The drag link looks to be on a pretty severe angle from the pitman arm to the right front spindle. How is this not going to cause bump steer as the springs and axle deflect?
Any particular reason you cut the org front frame off as opposed to just removing the suspension? Are you going to add any more bracing, or just let the front cross member hold it all together? Seems like an awful lot of extra work to lose a few pounds on a street car. All in all it looks cool, A nice 2x4 301" Chevy would be right at home in there.
Using a stock width early ford axle does set the wheels in a bit, especially if you run spindle mount wheels. From experience with my own straight-axled '57, I would take measurements of wheels, brake components, spindles, etc to calculate the width your axle should be to end up with a stock front track width. This is my wagon with an MAS axle, I would have liked it a couple inches wider. It had 15x5 early vette type steelies on the front. When you put an axle under a tri-five, the stock crossmember ends up very close to the axle. By subbing the front, you gain tons of clearance for when the front end comes back down after pulling the wheels. It also makes mounting the springs easier. BTW, I have an article that shows how Blair's speed shop used to install axles under tri-fives and they used 2x4 tubing for the main rails so the transition to the stock frame was easier. I'll see if I can find the article & post it.
Thanks for the clarification on the axle to crossmember clearance. I didn't realize it was that tight. The pic really puts it into perspective.
Hey WHITEWALLSLICK thanks for answering that also. I hadn't had a chance to go back and review and you pretty much nailed it.
Just keep lookig at this post. Makes my heart beat alittle faster! Wonder what my '54 would look like set up like that.... hmmmmm =)
Cool post.....good job. Quick question, was there any reason to mount the shackles to the front rather than the rear, seeing how the rails are straight?
Not Really. The Off road guys sometimes claim that a rear mounted shackle rides better, but I don't know if I really buy that. Some say with a rear steer, front shackles bump steer less and vice versa. Never really mapped that one out to see if it's true. We started doing them this way along time ago after one I built had the headers real close to the tires and on a hard bump or after a wheelie that tire would rub the headers as the axle moved back wards. By moving them top the front, no more issue as the axle now moves slightly forward instead.
speedway now will sell you a straight axle up to 50 inches whick work great on a tri five. we do ours similar,we use 4 inch also, nice job.
Ahhh...yeah, that makes sense on a street/drag car....hadn't thought of that. For offroader's, the combination of big tires and the flex that happens within the shackles, will wander if in front. And the ride is better, as the axle travels back when hitting a bump, not forward (fighting against the bump, ya know?)
Wow. Very clear, staight forward installation. The only way it could be easier, would be having hotrodron do it for you!
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