BUILD Shawns 1971 Impala Donk

cap42

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Do you have enough room in the wheel wells to shorten the axle and widen the wheels? Or are you just keeping the same width and just changing the mounting offset?

I have to agree on the 9", by the time you beefed up the 12" your probably cost ahead and have a stronger rearend.
 
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Shawn1112

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Do you have enough room in the wheel wells to shorten the axle and widen the wheels? Or are you just keeping the same width and just changing the mounting offset?

I have to agree on the 9", by the time you beefed up the 12" your probably cost ahead and have a stronger rearend.
Rear frame is notched already, so yes there should be enough room. Rim will be the same width, what they do for the wider barrels is just set the face of the rim deeper on the rim. So yes I suppose the offset changes with that being said
 

Dr. Jimbo

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corvette dubs GIF


do it
 

LikeABauce302

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9" is the way to go. They make life easier since the entire center section is removable from the housing. It's super easy to remove and replace axles, plus they retain the axles to the housing by design. No need to mess with c-clip eliminators.
 

strtcar

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It's super easy to remove
o you young kids sure it is on a lift 5' in the air....1hr on my back with the car 18" in the air, hitting everything, playing the balance game on the jack, trying to get in at any angle I could....not fun
 

GLADIATOR

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Is it leaf springs in the back or coils? I would legit 4 link it with coil overs if you are going with the 9”.
 
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Shawn1112

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Why a 9 inch over a 12 bolt? Go with a 12 bolt for the heritage !
There isn’t anything left on the car that goes with the heritage. So why start now lol
Is it leaf springs in the back or coils? I would legit 4 link it with coil overs if you are going with the 9”.
Double adjustable coils all the way around
 

Bob Kazamakis

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I just bought Yukon 33 spline axles and a Detroit truetrac for my 12 bolt. It was nowhere near the price of a 9”. Diff was $600, axles were $300 (thanks price match). I’ve already got gears but I think those were less than $250.


Now if your intentions are narrower for more lip then a quick performance 9” is what I’d do. They can do full custom for a reasonable price.
 

Dr. Jimbo

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If you want someone local that will build a really nice 9", VRN Welding in Lake Bluff did my rear end a few others that I know.

Otherwise you can't go wrong with Quick Performance.
They do a phenomenal job. Have used them on a few things also.
 
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Shawn1112

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Talking to people in the big rim scene including the guy who did all my suspension. Quick Performance is the way to go even more so if I’m shortening the rear end. 4.10 gear sounds like what I should be going with as well
 
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Shawn1112

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Yes to a point, but with the bigger rims/tires doesnt it effect the gear? If I had regular size rims and tires then yes the 4.10 would probably blow the tires off.
I have 3.73 now and I think that with the big rims/tires it really effects how the car leaves from a dead stop.
I by no means know as much as you or others when it comes to rear ends and gearing. I'm just going off stuff I read and input from others. So if I'm wrong, please correct me.
 

IceCreamAssassin

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Yes to a point, but with the bigger rims/tires doesnt it effect the gear? If I had regular size rims and tires then yes the 4.10 would probably blow the tires off.
I have 3.73 now and I think that with the big rims/tires it really effects how the car leaves from a dead stop.
I by no means know as much as you or others when it comes to rear ends and gearing. I'm just going off stuff I read and input from others. So if I'm wrong, please correct me.
You are correct, but you are also adding a supercharger correct? That's gonna be instant power so depends how hard does it leave now with the 3.73, because it's gonna be a lot harder with the supercharger. Also what's your rpms at like 60 mph while cruising?
 
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Shawn1112

Shawn1112

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You are correct, but you are also adding a supercharger correct? That's gonna be instant power so depends how hard does it leave now with the 3.73, because it's gonna be a lot harder with the supercharger. Also what's your rpms at like 60 mph while cruising?
It leaves like dog shit right now lol. But once them big wheels get turning, it moves pretty well.
I'll have to check on the RPM's at 60mph, I'm usually doing at least 80mph on the expressway.
 

Bob Kazamakis

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Talking to people in the big rim scene including the guy who did all my suspension. Quick Performance is the way to go even more so if I’m shortening the rear end. 4.10 gear sounds like what I should be going with as well
Makes the most sense with that rotating weight AND wanting narrower. In reality I should of oribanly just sold my stock 12b and bought a fabbed 9”.
 

Z28Camaro

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Given the power you will make, I would calculate what MPH you expect to be at at the top of the 1:1 ratio when going through the traps in the quarter mile. You probably want to set the gear ratio to match going through the traps at or just below redline.

What torque converter are you running?
 
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