Hey ppl, I haven't really had a good chance to take a look at the internal structure of the car, but I was wondering what would be involved in doing a mini tub on a 4th gen car. Mind you this will be an open track/street car, all the suspension pickup points are braced with a roll cage so structurally, the car is quite stiff, but how much of the car's stressed structure lies within the rear wheel wells?

I'm looking to fit a 28x14.5-18 Good Year in the rear.

Thanks.

 

You building this to fit within certain class regulations? If so, which class??

-Mindgame

 

No regulations whatsoever... open track days and such.

 

This is more appropriate for "drag racing" or "LT1 Tech"..

Moving to Drag Racing.

 

I take it that you want to maintain the stock rear suspension?Measure from the inner wheel lip to the closest suspension point or frame rail in the front of thewheelhouse middle and rear..The smallest measurement is you maximum allowed room..You want to stray away from chopping up the frame rail if you can..You want to at least buy the wheels and tires you plan to run so you can tuck em up under there.. You may find that the 1/4 panels may need to be enlarged a little unless you tuck the tire deep in the body..

If you plan to still run the stock unequal 4 link setup..This being the easyiest way..You can go to 1/2" away from the control arms with tire..Trim away the wheelhouse and replace it with a set of standard wheeltubs..The 90* design of the wheeltubs will allow for a taller tire and also by the trimming you will have the width you want..Depending on how tall of a tire you have and how the car sits at ride height you may be able to keep the outer edge of the factory wheel house..Tie your tubs into it and seal it up with tack welds and eurothane commonly used for windshields..Dont use silicone as it holds and attracts water..The eurothane will help stiffen up that section of the car a tiny bit too..If you want more height then you will have to trim out the factory tubs completely as well as some of the inner walls of the car..No big deal at all..Just a little harder to trim..Wheel houses dont support that much but when you remove them the cage will handle it for you..In the rear along with the standard kicker bars have an X brace installed..From you kickers about mid length i would run some tubing to the main hoop..Its all about triagles here..Make sure that the rear bars are directly on the rear frame rails with a good abount of plate..

Put the tallest tire that you can fit as long as it looks good to you..I favor 13X31s for open track cars since going smaller doesnt look that bad if you run a 10.5W..Look into 30X9s or the common 28X10.5s.Put the widest wheel you can on them too..That will help at the big end.

That being said and you wanting a street car thats about as far as i would take the rear suspension..Ladder bars would be a great choice if you didnt want to drive the car around..4 links are better for teh street as they will allow for true free movement of the rear axle but the cost of rod ends will kill you..Consider them wear items if you drive around and junk if you get caught in the rain..Priced at $50 ea for a decent one you will have to replace 10 at the least with a panhard bar and 11 with a wishbone..the packageing gets more costly since you need a fuel cell coilovers rear axle 9" or common 12 bolt etc etc..

If you can do without driving it much then id say ladder bars but its best to do that with a new rear frame section..It can be done with the stock floor but performance will suffer and the chassis wont be as predictable..

 

I greatly appreciate the input, I figured it would be a pain in the ***. This is for road racing, not drag racing, but anyhow, I will take a look under there and see what I can do, if it looks like it will be too much to deal with I will sell it and just build my own damn project.

Thanks again man, much appreciated!

 

Not a 4th Gen but a mini-tub non the less. www.azsupersport.com/minitub.htm

Mike

 

www.madmanandcoracing.com

he does minitubbing for about $2000. give him a call.

Basically what he does is uses tubluar LCAs with an offset spacer to push them inside more, then he also uses 2.5" diameter rear springs instead of 5" diameter ones, and lastly he cuts out the tub and puts in a new one to take advantage of the newly created space.

All of the suspension attachments stay the same and dont move.

hope that helped

thats a pretty cool link and should give you a couple ideas but just remember we dont have frame rails back there like an impala does. The act of minitubbing a f-body is more like creating space in a closet with one of those organziers. You really aren't chaning the size of the closet much but rather creating more room for things to fit

 

That reminds me why I am glad I'm too big and have too many kids to fit in an Fbody....
:P

Mike

 

lmao @ mtxpert