You guys that have installed a MP inboard spring kit...could you give me an idea on how big of wheel and tire,and back-spacing, my '69' GTX could use? I can only fit an 8" wheel,with 4.5" back-spacing..using a 9"x30" slick! I need to step it up and get more rubber under the car! Thanks in advance for your answers! Randy B.

15x12 with 3.5 back spacing for the rims. M/T 31x10.5W's or 13x31's with a "little" trim work to the front of the wheel lip.

Jeff

Randy,It's your car,but I wouldn't cut that GTX at all.Our 70 Road Runner used a 10" wheel with a 5" offset,and we had 10.5x29.5 Firestone(Phoenix) in that car with a bit of trimmimg of the front edge of the wheelwell.Lips were trimmed too.I don't think you'll gain a whole lot by going to a larger tire that you have in mind.In fact,on my A-body,I'm going smaller after I have the car painted.From 31.8 to a 29.5 tall tire.

This isn't necessarily a direct answer to your question, but it is more of an response that may have you looking at other areas of your car.

What are the particular specs of your suspension package.
- Front and rear.

Do you run Cal-Tracs and Monoleafs?


For a good example of hooking a 540 stroker B-body using a small tire, look at ActionAnge.
He hooks his 3750lb 1967 Belvedere to the tune of 10.27 @ 132 with a 1.44 60ft, using a 9x28 slick on an 8" wheel.

Brent...that's one impressive Belvedere AA has! I see he uses Cal-Tracs out back. Do you know what else he's done to the suspension to make it hook so well? My 3500 lb. GTX has NO front sway bar,.840 Race T-Bars...and Calvert Racing 90/10's..which work GREAT! Out back are 002-003 A-Body Super Stock springs,as used on the '68' Hemi Darts and Barracudas. The shocks are Rancho 9000 9-way adjustables. Rear gear is a 8 3/4..4:56 ratio. I believe the pinion angle is 5* angled down. Thanks for the info! Randy B.

Why do you need bigger tires? Just want the look? Many NHRA stockers and Super Stockers go into the 9's on 9 inch tires.

Rod..yes,a big part of it is "the look" I would really prefer a mini-tub...but budget(and wife)most likely would frown on it,I'm sure!

..... She'll never know!

Randy

Not sure if my uncle moved in his springs on his 68 RR but he runs 28x14.5 QTP's with NO tubs!!!!

Mikes Duster,,,,NICE car,,,

http://www.youtube.com/watch?v=u8wb7JAM5wc The top of the rim is above the wheel opening.Wanted the lotsa rubber look without the downhill angle. 315-60-15 Mickey Thompson radial http://i355.photobucket.com/albums/r461/FriedDonuts/P1000654-1.jpg

I have a 67 b body with a stock width 8 3/4 and run a 28x14.50 quick time pro on a 12" wheel with 6 1/2" of backspace. If I went to a 7 1/2" back space I could go with a wider tire, There is alot of room behind the tire to the spring due to the stock width rear end.


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Randy..you're so creative! ....Mike...LOVE your uncle's RR!..could you find out what he did to fit such a big tire under it? Thanks! .....Eric,BEAUTIFUL Satellie! Your springs are moved inboard? What size wheel and tire are you running?....Matt..NICE Charger! I'm REAL surprised 14.5" wide tires will fit after installing this kit! That's more than enough tire to make me happy! Thanks for your help,fellas! Randy B.

The bolt on inboard spring hangers won't even bolt on!

The front hangers are already right next to the frame rail on your/our car. There isn't anywhere to go, no
wasted space to use up.

The bolt ons work much better on an A body, but you still have to punch a hole in the frame to clear the fasteners with those.

The weld-on spring relocation kit, which is the only mp setup that will do much of anything on your/our car(s)
requires chopping a chunk out of the frame rail to weld in the mounting boxes. Then after the spring is relocated, the next obstacle is the wheelhouses....

If you only relocate the springs
and don't relocate the inner tubs, you're only going to gain about 1" of tire even though you moved the spring 3", which is not a very good payback for the effort.,,,,but it could be done that way if a guy wanted?

Since the quarters and various other sheetmetal needs to be cut off mine anyway, being rusty junk....and the frame rail is already cut for the subframe connectors, I'll probably go the extra mile with it when it's time to replace the quarters. It would be kind of a shame to cut yours, but I wouldn't blame you if you did!

I also like the look....big car, big tire...why not

I think cutting the frame is not so bad if it's done well, as it's not easily seen but i wouldn't cut the body on your car for bigger tyres.
Mick

Thanks for all the GREAT info,Angelo and Rich! Looks like I'll have to find out how involved and how costly it's going to be to do the wheelwells as well as install the kit! Zippy..if I only gain 1" out of it,I'm not going to have it done! I'd like to be able to put at least a 12" tire under it. Thanks again,guys!

Mick..NO WAY am I cutting into the body..not even the wheel well lip!