Back half advice

[a1953mdl]

I am needing to back half my truck. The previous owner has already cut off the frame.
The frame has been boxed from the cab forward. I am planning to use the trailing arms and I am thinking of just adding 2X4 from where it is cut to the back. What would I need to use for bracing?
It may be a season or two before I "need" a cage, but I want this truck to be pretty stiff and go straight.
What are your suggestions?
Here is some pics of what has been done.






I plan on using coil overs on the rear.

Lee

[rookierodbuilder]

I do not know much about chassis work, but if that were my truck, I too would keep the trailing arms, I would put the frame rails closer together for wider meats and set it up with an adjustable anti-sway bar and some adjustable coil-overs. A quick and dirty way of doing that would be to order the back halve kit for a four link from a race parts supplier and modify it for that purpose.

[joeys66pickup]

Dude that chassis looks sweet! is that diamond plate for your frame boxing?

[a1953mdl]

Originally Posted by joeys66pickup

Dude that chassis looks sweet! is that diamond plate for your frame boxing?

Thanks, Diamond plate it is. All of this was by the PO that got bored and went on to another project. At least most all of what he did was nice and we got a good deal on it too.

[a1953mdl]

The back half will need to "kick up" 10-11" to get the rear to match the fronts height. .
I'm wanting to use 2X4 rect tubing. just angle it up, then run it back to the back of the bed. I will need at least a cross brace for the coil overs.
Would running 2X4 for the coil overs be good? Too much, not enough?
What other bracing would help to make it strong and reduce flex/twisting, without adding unnecessary weight?
It doesn't seem like much is used when you back half a car and with the trailing arms cross member mounted in the original frame area, I'm not sure what else is necessary.

[djracer]

I would just use 2x3 here's how mine looks.

[a1953mdl]

Kevin, I often check back on yours to check out what works. Thanks for the great build thread and pics.
I may not go with a cage for a while. Wondering how that would affect my frame and any twist.
Most drag cars I have been around that have been back halved also have cages.
I may have to bite the bullet and cage it, but wanted to get going soon with a NA engine and work into things.........

[djracer]

the cage strengthens the chassis but I think the rear frame would be fine without a cage for awhile.

[hotrod 80]

I agree with the 2x3 square . Looks like the trailing arms are just tacked in the truck to move it . I would build the kick up with upper shock mount , buy or build ( i would buy ) a set of ladders , fab a front mount cross member and hang a 9" under it . No offense to the trailing arm guys in the group , but your this far just finish the rear and go racing .

At this point the tire choice needs to be made . I would pick a tire and rim combo with a common ofset or back space and build the backhalf for it . This may not be the correct way , but it is the only way i know . I built mine to factory specs and wish i had done some research first . I would have narrowed the rear axle to take 5.5" back space that way i would have the same wheel most mustang and camaros use . You'll probably run a bigger tire than me . There are alot of true 10.5 race cars down here so 29.5 x 10.5 x 15's can be had with 8-10 passes on them for $100-$150 a set . A guy could set his rig up for a popular tire like that and and get tires on a budget . just a thought . Raland

[a1953mdl]

The tack on the trailing arms is just to be able to move it. No where to put the springs or coil overs. But the front is mounted securely to a custom crossmember.

29.6X10.5 Seems like a good size tire for me, even tho I am full size. Is there a commonly used size that you think would work better. I like the idea of using cheap available barely used slicks. But i have no idea what is commonly used.

I will need to be over tired for a while....until I can get the horsepower up a bit more. I would rather be a bit big rather than too small.

I have a 9" available and a fair selection of gear sets. So i can work ratio out after i select a tire.

Thanks for all the help.

[djracer]

I run take off 33x10.5w tires. They are cheap.

[hotrod 80]

I don't know if There is a big outlaw class in Dallas , but you could always look at a 10.50 W . It is like 11.7 " wide and they can be stiff sidewall or regular . They also can be up to 33" tall . Any "bracket/sportsman" race size tire is going to be used until it's dead . Alot of the grudge race guys use these take offs .

[a1953mdl]

Looks like 10.5 wide are popular.
Would you think that laying out the back half to have room for a 11.75-12 inch wide (sidewall) with 5.5 b/s wheel would give me the best chance for finding good cheap used slicks.
Also, Would a 10" wheel be the correct width for the 10.5 wide slick?
Lee

[djracer]

I run a 10 inch wheel but I want some 12's! A twelve is a better fit for the w tires!

[hotrod 80]

Originally Posted by a1953mdl

Looks like 10.5 wide are popular.
Would you think that laying out the back half to have room for a 11.75-12 inch wide (sidewall) with 5.5 b/s wheel would give me the best chance for finding good cheap used slicks.
Also, Would a 10" wheel be the correct width for the 10.5 wide slick?
Lee

Yea , i'd lay it out for a 33x13 and run a 10.5W . That way it would just be a tire change not a rebuild . The W's come in 29.5 , 31 & 33 . The true 10.5 are popular in 28 & 29.5 . Giys down here are running below the 4.teens on W's and like 4.66 on true 10.5's .

[a1953mdl]

Don't think I will be able to start on this before I leave for another job (and be gone for a WHILE). But this lets me start gathering parts. I will go of the 12" wheels and allow for "up to" a 13 wide slicks.
Thanks for all the help.
I have more questions and will start a new thread for those.
Lee