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Topic Review (Newest First)
10-20-2012 06:39 PM
Too Many Projects Thanks Todd, I'll check into the mods you suggest and weigh the cost against swapping in a 8.5. I located 2 about 60 miles from me. They would need a power trax or similar installed for posi.
10-20-2012 08:58 AM
big gear head The Malibu 7.5 is 58 inches wide. That's 2 inches narrower than a Nova rear end. The 7.5 is not very strong, but you can help it by installing a 28 spline Eaton Posi, 28 spline Moser axles, T/A Performance cover and correctly setting up the gears. If your 7.5 is mounted by the axle tubes then you need to strengthen them too. The 7.5 has 2 5/8 inch tubes, which are not as strong as the other GM rear end's 3 inch tubes. You can fully weld the tubes with nickel to help hold them in place in the center casting. The plug welds tend to break when the rear end is mounted by the tubes. Nickel is the only material that you can use to join steel and cast iron. Welding them with steel will look fine, but it will break away from the cast iron if it's stressed.
10-20-2012 06:14 AM
Too Many Projects
Quote:
Originally Posted by big gear head View Post
It's going to depend on how wide you want it. The X body rear ends are 60 inches wide and the 2nd gen F body rear ends are 61 inches wide. (....If you don't need strength you could use a G body 7.5 rear end that is 58 inches wide.....)

That chart has been around for a long time and is in serious need of some corrections. The '67 to '69 Camaro, '64 to '67 Chevelle and '68 to '79 Nova rear ends are all exactly the same width at 60 inches. The chart has them all different. Also the '68 to '72 Chevelle and '70 to '81 Camaro rear ends are 61 inches wide, not 62 1/2 like the chart says.
Todd, I am getting a '38 with an '80 Malibu 7.5 axle already in it. Is there any way to increase the strength of the components and add a posi ? It may be easier to modify it than hunt down an 8.5 Nova axle.

Thanks !!
10-10-2012 08:08 PM
spacytracy I will try to pull the rear wheels off my coupe in the next couple of days and get accurate measurements for you. My tires have almost no sidewall buldge. Anyway, I'll try to get back with no question answers to your questions.
10-10-2012 03:44 PM
big gear head Wheel width is not measured at the outside of the wheel. It is measured on the inside where the tire bead seals around the edge. Back space is also measured here.
10-10-2012 01:06 PM
Too Many Projects
Quote:
Originally Posted by Leakie View Post
Hey spacytracy, how are you measuring the "backset"??? I have the same width 8 inch rearend in my 37 and I have a pair of steel wheels from a Crown Vic that have 3 and 3/4 inch backspace. The tires just barely clear the frame, no where near enough for driving but they work for rollers. I was thinking I would need 3 inches or less of backspace. Maybe I am not measuring right? I thought you put a straight edge across the back side of the wheel and measured from the straight edge to the back of the wheel where it would butt up to the brake drum. Are you doing something different? If I had 4 inches of backspace I would not be able to mount the wheel because the tire would hit the frame. Thanks!
You're doing it right. If the tire is wider than the wheel, the sidewall bulge needs to be considered in the off set too.
10-10-2012 10:42 AM
Leakie
Quote:
Originally Posted by spacytracy View Post
I used a 8" 72 mercury comet gt rear in mine. Think it was 58" wide. Used 8x16 saltflat special american racing wheels with 4" backset with 225 55 16 tires. I have about 3/4" inside and out clearance.
Hey spacytracy, how are you measuring the "backset"??? I have the same width 8 inch rearend in my 37 and I have a pair of steel wheels from a Crown Vic that have 3 and 3/4 inch backspace. The tires just barely clear the frame, no where near enough for driving but they work for rollers. I was thinking I would need 3 inches or less of backspace. Maybe I am not measuring right? I thought you put a straight edge across the back side of the wheel and measured from the straight edge to the back of the wheel where it would butt up to the brake drum. Are you doing something different? If I had 4 inches of backspace I would not be able to mount the wheel because the tire would hit the frame. Thanks!
10-02-2012 05:07 PM
Too Many Projects Well, that turned into a BUST. I drove 18 hrs straight thru to TN and the car is much rougher than described or seen in the pics. It's still there...

I'm still looking for a street rod...
09-30-2012 06:57 AM
Too Many Projects Dave, I was thinking the same thing about the originality of it. I have been looking for a turn key rod or at least a project well along but didn't find anything that met my goals. I did find a couple that were close but I couldn't afford the 27-30k price tag...

I will most likely keep all the original drive train parts on the shelf. Many of the mods necessary to rod it can be had as bolt on.

I have ample room to store stuff but I need to purge a lot of what's here now to make room. I will be working on a '67 GTO basket case over the winter to sell as a roller next spring. I also have a '69 GMC K10 that will get sold and all the extra parts I have to convert it to a Chev. Those 2 vehicles and all related parts take up the area of a 3 car garage.

I'm leaving here in about 45 minutes to go look at and, hopefully, bring the '38 home from TN. If it's not what the owner described or the pics show, I will drag an empty trailer back with me.
09-30-2012 06:13 AM
Irelands child Looking at that car, almost a shame to change it, but why not! Just makes it better.

A 9" may be overkill, the 8" is a good compromise - that is if you can find one. I 'ended up' 7-8 years ago with a 9" simply because I just could not find an 8" that wasn't so rust pitted that it was well weakened. Also, the 9" has probably many more choices of replacement gear sets.

With that blather said above, another choice is the Ford 8.8 rear ends. Very available in salvage yards. Are 56.5(Ranger p/u & early Explorer) to over 61" (Crown Vic, etc) wide, depending on the source vehicle. Many have disk brakes, gear ratios go from the high twos to the low fours. Every part is still available at your local parts store (drum brake parts for an 8/9 incher are virtually impossible to find at 'local' stores)

Dave W
09-30-2012 05:56 AM
Too Many Projects You have a great car. I don't plan to spend 7 years converting mine but then I'm sure you didn't either. Things always come up and take time and money. I like the bumpers and running boards on these cars. Many I see don't have them. We are the home of MSRA here and have the Back To the 50's every year. They set a record attendance this year with around 15,000 cars 1964 and older on the state fairgrounds. Quite the spectacle to see...

I hear ya about riding like a truck.....I brought this back From Pagosa Springs CO last December. 1952 2 ton. This is like having NO suspension and with 6.13 rear gear it's goes a whopping 48 mph...



This was my daily driver for the last 17 years. 42 years of driving some type of commercial truck. I just parked this for good 2 weeks ago. Know anyone looking for a '92 Pete ...

09-29-2012 10:41 PM
spacytracy Great looking car! When I bought mine in 2003 for 4500.00 it was a running driving southern Idaho car. Thought I would just clean it up and drive it as an original car. First time in it I changed my mind. It felt like a truck! I now drive mine every day that the sun is out. So much more fun than original. Keep us up to date with photos as you build and hopefully it wont be a 7 year project like mine was.
09-29-2012 06:22 AM
Too Many Projects
Quote:
Originally Posted by spacytracy View Post
I used a 8" 72 mercury comet gt rear in mine. Think it was 58" wide. Used 8x16 saltflat special american racing wheels with 4" backset with 225 55 16 tires. I have about 3/4" inside and out clearance.
Thanks, that's good info.
Here's a pic of the car from the seller to change my "last pic".

09-28-2012 10:34 PM
spacytracy I used a 8" 72 mercury comet gt rear in mine. Think it was 58" wide. Used 8x16 saltflat special american racing wheels with 4" backset with 225 55 16 tires. I have about 3/4" inside and out clearance.
09-28-2012 07:30 PM
Too Many Projects
Quote:
Originally Posted by RWENUTS View Post
Sorry for the confusement. I'll dump that.
Here's a long tested method for finding out how wide your 38's rearend is.
diy d e s i g n: January 2011
I can't find my 1020 mile tape measure either. I will be going to get the car next week. Just trying to do research on what to get early.
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