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-   -   Those With Mini-Tubs...Would You Do it Again? (https://forums.maxperformanceinc.com/forums/showthread.php?t=880224)

JLMounce 05-02-2025 10:34 AM

Those With Mini-Tubs...Would You Do it Again?
 
Question is the title. I'm considering doing mini-tubs on my 69 as it's in need of more tire with the new engine I built.

It was never something I intended to do because of issues relating to the back seat, the amount of surgery it actually is on good factory metal in my car.

If you've done this, or had it done, what were the pitfalls, if any that you ran into? Hidden costs or issues you didn't know about?

My back seat rarely ever gets used, so losing it isn't the end of the world if that would become necessary.

Any experience on this would be helpful. Thanks in advance!

Gator67 05-02-2025 11:01 AM

I've done two second gen's, no regrets. Both are pro-touring type cars with aftermarket 4-link suspension and 335 18 sized tires. Not sure how wide you can go on a first gen without interference with original leaf springs. Both cars have back seats--just modified the rear seat frame and had new the covers made/modified by an upholsterer for a finished look. On one I modified the armrest panels to fit, on the other I just stretched the armrest panel to fit. The former looks better, but was a lot more work and might not hold up over time.

JLMounce 05-02-2025 11:38 AM

Quote:

Originally Posted by Gator67 (Post 6563016)
I've done two second gen's, no regrets. Both are pro-touring type cars with aftermarket 4-link suspension and 335 18 sized tires. Not sure how wide you can go on a first gen without interference with original leaf springs. Both cars have back seats--just modified the rear seat frame and had new the covers made/modified by an upholsterer for a finished look. On one I modified the armrest panels to fit, on the other I just stretched the armrest panel to fit. The former looks better, but was a lot more work and might not hold up over time.

69 Model year cars can fit a 335 with leafs if they have offset shackles and a notched fuel tank. Some lip rolling may be necessary at that width. I'd probably convert to a SpeedTech torque arm link setup in the rear at that point.

I would probably run a Corvette C6 GS wheel size as it has a plethora of tires available for it. 19x12 with a 325 section width. That would give me 50mm more contact patch in width and would increase roll-out patch from the 27" overall height compared to my current 275/35/18's with a 26" height. Both would significantly help traction without the need for a drag radial.

65madgoat 05-02-2025 01:59 PM

ZERO regrets on a first gen. A must. Get on it! Been waiting for your to do it. And no need for 335s. I'd stick with 315s in back since you are only so wide up front. 18x9 front and 18x11 rear is ideal in that case.

265 front
315 rear


And yes SpeedTech torque arms kits are the ticket these days as their kits put power to the ground the best.

hojs69 05-02-2025 03:28 PM

Same here. Zero regrets using the DSE version.

I also kept the backseat, aesthetics only. Not much work to "notch" corners and such.

Rear tires 390 / 45 x 15
Section is nearly 15 inches
Tread 12.5 inches
Wheels 15 x 12" (Budnik Arrowheads of course)

https://www.summitracing.com/parts/M...kaAo2oEALw_wcB

You can "stretch" the width of the tubs slightly during installation without harm.

JLMounce 05-02-2025 09:05 PM

Appreciate the experiences.

madgoat how are you fitting a 9" wheel with a 265 up front? I have a 245 on an 8.5 right now and do rub slightly.

65madgoat 05-02-2025 09:22 PM

Stock subframe but wilwood discs and 5" backspacing on 9" rims and no rubbing. Have over 5° positive caster and -1.5 camber.

JLMounce 05-02-2025 10:50 PM

How low is the front end? That's part of my issue. By car is very low, it limits how far out I can stick the wheel.

Current alignment is at -1 camber, +6.5* caster 1/16th toe in.

65madgoat 05-02-2025 10:56 PM

I mean I'd have to check fender height but I feel sits right with coilovers. 265/35 tires with fender about 1/3 over the top of the sidewall if that helps

JLMounce 05-02-2025 11:20 PM

1 Attachment(s)
Oh yeah, my car is functionally lower than that...by a lot.

I can put a 255 on this wheel though, I just like a little bit of stretch on the tire to help turn in feel.

Attachment 651160

65madgoat 05-02-2025 11:46 PM

Yeah that is low. I gave up going a half inch lower so I can drive everywhere with no issues.

JLMounce 05-02-2025 11:53 PM

Quote:

Originally Posted by 65madgoat (Post 6563152)
Yeah that is low. I gave up going a half inch lower so I can drive everywhere with no issues.

I actually don't scrape everywhere I go. I don't even really have to worry about how I drive the car. This angle makes it look worse than it is because the car is straddling a fairly sharp bend in my driveway.

The front wheels rub the large inner fender washer at full lock, that's about it.


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