tire size back half frame kits tire width on 70 mustang

i am looking at welded s&w frame kit for ladder bars or 4 link havnt made my mind up which yet

fram rail widths are 24,26,28 any idea what the 28 will be for tire size ??

i wanna run a 15x12 with a 315 radial or 29.5x10.5 or 10.5w without have 2ft of clearance




i dont wanna big tire stuff aka tank tracks

FWIW my old full chassis 69 Mustang had 15x33.5's and I think the 2x3 frame rails were 24" outside to outside (IIRC).

I can see not wanting too much clearance on the outside (sidewall to fender). But if you don't mind having some extra clearance between the sidewall & the frame rail you could always build it with narrow frame rails, and just use a wider housing to place the smaller tires out close to the fenders. That way if in the future you wanted to go to a wider tire/rim you wouldn't have to redo the frame rails. You would just have to narrow the housing again, (or use a wider rim with more back space).

good point

was looking as well .....there are some guys flying on split mono leaf with caltrtacs and mini tubs with d/a shock on 10 inch wheel

issue is i have to replace torque boxes so it needs to be cut up anyways

im still going to use ladder bar frame kit , but those leaf cars seem to be moving on out as well


Any reccomendations on what brand kit to use ?

now back half ing the car say 2x3 frame kit and using 2x3 frame connectors to front frame .....is this considered tube car ?

my rules say square and round tube chassis not allowed . I may be asking a dumb question but if i use 2x3 rear frame rails and to the front dont i fall in that area ? or they talking about full blown 25.2 25.3 tube chassis car like pro mod

5pointslow wrote:.......Any reccomendations on what brand kit to use ?....

I can't suggest a back-half chassis kit cuz I usually like to build from scratch.


 

5pointslow wrote:.......now back half ing the car  say 2x3 frame kit and using 2x3 frame connectors to front frame .....is this considered tube car ?

my rules say square and round tube chassis not allowed . I may be asking a dumb question but if i use 2x3 rear frame rails and to the front dont i fall in that area ? or they talking about full blown 25.2 25.3 tube chassis car like pro mod

My interpretation when a given class rule says "no tube chassis" is they are usually talking about a bumper-to-bumper full chassis car (having zero factory frame remaining), and not a back-half or mini-tub deal. Of course what some people are calling a "back-half" car these days is getting a little out of hand IMO with some cars only having a small sliver of the front frame rails remaining.

The SFI 25.1, 25.2, and 25.4 specs are more aimed at a full chassis type car (all factory frame/chassis removed, and any remaining factory body shell provides no/zero structural support). The 25.1 & 25.2 spec must be all round tube & the tubing must be all 'moly material. The 25.4 spec can be your choice of round or box tube, and your choice of 'moly or mild steel material. The 25.1 max weight is 2800lbs, and is for 7.49 & faster ET. The 25.2 max weight is 3200lbs, and is for 7.49 to 6.00 ET. The 25.4 max weight is 3600lbs, and is for 8.49 to 7.50 ET.


The SFI 25.5 specs is more aimed at back-half, mini-tub, and stock suspension type cars (some given amount of the factory frame remains, and the body shell is still considered a structural component to some degree). And with 25.5 it's your choice of round or box tube, and your choice of 'moly or mild steel material. The 25.5 max weight is 3600lbs, and is for 8.49 to 7.50 ET.


The 25.3 spec is a fairly new one. I don't have the book, but I think 25.3 is a "catch-all" spec aimed at most any car chassis/body type (full, half, mini, SS) that is a faster car and is also a fairly heavy car. I think it calls for any new (non factory) frame/chassis structure that's added must be all round tubing, and must be all 'moly material. I think the max weight is 3600lbs, and is for 7.49 to 6.50 ET.

my turd is not a "chassis" car, just a backhalf...... "tube" or "chassis" car has aftermarket framerails front to back.