Im putting a set of weld pro stars on my 89 Firebird drag car. Will not see the street ever. The rears are 15x10, 6.5” backspace, with a 28x10.5 slick. We cut the bump stop area to fit the wheel and we have plenty of clearance now. But we cut both layers of metal above the bump stop which exposes the spring and rear shock. I’ve read on this forum to only cut the first layer. We cut them both but left 2 layers of material up near the top spring perch.

is cutting only 1 layer a structural issue or is it purely aesthetic. I don’t care if it looks stock, just don’t want to compromise the rigidity of the frame. ( I don’t think we did). I would just like some opinions. I’ll post pics later today. Thanks.

 

 

It is structural, id plate it back in with 11ga as close to the spring as you can.

 

Agreed. You want to box that in.
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Yup. Just some heavy gauge sheet metal and weld it back in to fill the hole will be fine.

You may want to test fit your tires to see how much clearance you have at the front inner radius of the wheel well. That tire rim combination may have clearance issues.

 

Thanks guys. I’ll box it back in. AlkyIroc, so far the tires fit pretty good with 12psi. Im going to massage the passenger side a little more just to be safe. All in all they fit better than I expected. Lowering the front end is next.

 

Not really needed. When mini tubs are done on these cars you leave that open anyway. Id say you are fine

 

I'd still box it in. I'm tubbed and boxed that in due to the thin steel out in place of the wheel well. These cars are flimsy enough . A simple plate secures it nicely.

 

I agree with the plate it in idea. Chances are on a drag car that sees no street it would be fine left as is. Only thing really back there is the panhard rod reinforcement mount. That being said, still seems sketchy so I would plate it over.

I am mini tubbed and plated over mine with some thick flat stock from the local hardware store. Easy day job. Doesn't have to be pretty either.

 

Back when guys first started removing the bump stops. I forget who started removing only the first sheet / cutting. but it is best to just cut it all out like you did. has the 2nd sheet is beer can thin. lol.
then take sheet metal. and with a slight bow. outward away from the spring. just cover/replace. what ya removed. some do some. don't. I did. but then I removed all the inner lip.. the end of the ribs you have left. slice/ cut horizontally top of rib. back about 1" inch and fold over tapping with hammer. the weld the lips together. this folds the rib back together making a better-looking fix for what you just cut out. (my opinion).
sheet metal used can has thin has Dubble body skin. not too thick. for some reason .064 is stuck in my head. . lol.

below this pic shows rib removed


THIS Layout IN YELLOW showing the shape of the plates and cuts made to fit the tires. on both sides.


below what it will look like (note rib left in I removed it later on) for more room. show in a pic above few pics back. (this is a before photo)






below removing the first skin. this is a complete waste of time DO NOT DO IT! has the sheet left is beer can think and flexes with your fingertip... not joking. also showing yellow line the lip you will push back adding room. clean up.



below passenger side. top strap is 1/16 thick steel added to top of sheet steel. bowed out. to clear coil overs going in after this mod. (there is plenty of room). is one wants to add the same 1/16th plate to replace what you cut out. then go ahead. in all you could just leave the plate in and just cut out the bump stop lips has this plate is not taking much if any room for tires.


below. showing at that time welds new RTS wheels. and how fitment works.


when I did mine. I took all the outer sheet metal in the wheel well. and moved it right up to the interior plastic. so inside it looks stock. but you can fit 13.5 wide tires on the car.
shown below. micky Tompson sportsmen 29x13.5x15 under the car. or 325/50/15 are my others.




also, offset lower control arms. (note bushings) off set/ moves arms in so the section width of tire fits better. something to look at if wanting the widest tire foot print.


by the way there is disk brakes inside this 15inch rim.


with a 1/4inch clearance. they fit (even the E brake cable paw.

most guys don't run this wide a tire. but you can. if you want. I can only go 29" tall. has the ground FX limit me 1992 Z28. Below. this shows tire at lowest suspension hang. and how close it gets. tires at speed will grow. and could get sketchy.

but in the end, they just look good with the tires tucked under the lip. (no joe dirt) some time ago I did a full post on doing this.