Hi Guys.

I'm at the point where I will either get my 64 trailing arms rebuilt or buy new ones.
I'm mostly set on rebuilding the arms, but, I keep looking at the offset ones and wondering if....
I know I can stuff a bigger tire in the back with the offsets, but, what would the down side be.
The engine is a 454 and will have about 500hp so I don't want to cook the tires constantly.

I did a search on the forum, but, nothing comes up, or, I haven't put in the right search.
( which is more probable )

Any suggestions will be helpful.

Thank you 1
Dom

 

What rear gear are you running?

 

What size are your wheels? If 15" you'll benefit from the offset arms. If you have larger diameter wheels, look at relocating the parking brake bracket and keeping your existing arms. You might find doing that will give you enough clearance for wider wheels. Also, look at the bump stop on the frame. That sticks out to the outside of the frame and may cause an interference. If so, it can be cut flush to the frame and a '65 or later bump stop can be used to mount it inboard.

Patrick

 

856666

I'm running 3:73's with the original Muncie Trans.

Thanks,
Dom

 

Patrick.
I am/was running the 15's. I wasn't thinking about going larger, just wider.
I have 3:73's in the rear and the original Muncie.

Thanks,
Dom

 

Without going to a later Muncie and later C3 rear I would think your going to break parts with wider tires

 

Excellent point. As usual.

I'll stay with the original Trailing Arms and have them rebuilt.

Thanks,
Dom

 

Hi Dom,

I was pondering your same dilemma a few years back.

I decided to do both and so I ordered a set of 2 inch offset trailing arms from Year One and sent my originals to Bair's for rebuilding. While the originals were being rebuilt I put on the offset T/A's. I did have the intention of switching them back but I never did. I really like the look of larger tires on my car and the offset T/A's allows me to do that without having to modify the body or move the parking brake bracket. They are a bolt in item. I am running 245/60R15's in the back and 235/60R15's in the front and IMHO they look good and I have no body or frame rubbing issues at all.

I wouldn't worry too much about breaking anything with your current motor and wider tires. You are the only one who drives your car and you decide when and how much to get into it. If you don't constantly nail it or drag race your car at a drag strip you will suffer no damage. You are the one driving. I am running a 427/480hp motor with a 4:11 rear and have no issues because I no longer drive like I did when I was 19. I would be dead now if I did. I vote for offset trailing arms and wider tires. Good Luck with it. C.J.

 

You know C.J. - we sure would like to see some pics of your set up! C'mon man!!! 😜
Tom

 

This is the extra bracing that was installed by the mechanic that owned the car before me.

 

Dom
I have examples of stock and offset arms in my shop if you want to see them.

Looking at your picture I see some things you should be aware of in case you aren't. The axle seals are leaking in the diff, you have to check to see if they have crashed into the diff.

That looks like a homemade traction bar so the car was probably pushed hard at some point. The 64 diff may be gone by now since they were weak and came apart with some power and abuse, same for Muncie cases. If there is a stock C3 diff in place they have soft face axles that will crash into the diff if left. If you are unsure about any of the parts in the car let me know and I will go over them with you.

If this is an old school street car from the 70's you probably have a few things that took some abuse and may be ready to go at anytime.

The spring has a shipping strap on it.

You still have the stock 64 trailing arms and drum brakes.

If you are looking at 500hp under the hood with a drivetrain designed for 300hp and one that has some weak links you should think about some mods.

The stock arms, if not rotted or bent are strong. We ran them on the track no problem. The offsets will allow a wider tire but you might want but you might want to consider changing to a disc setup front and rear, it will make a difference.

Stock 17 spline outer axles are good to about 450 hp, which is subjective to several things. They usually will break at the base of the threads.

If that is a 64 differential it would have 370 gears and 64 diff's had terrible pinions, spiders and posi cases. You can look at the date code, see if the front bracket bolt is tapped or through hole, see if the upper 2 cover holes are blind or through holes. Looks like the body is off the frame? You will want to use a69-79 diff bracket as well. 63-4 were junk.

So your plan of use needs to be thought out otherwise you will be revisiting things in the future.

 

 

Tom,

Thanks for asking. There are a few pics of my car on the recent "Happy 427 Day" thread ( https://www.corvetteforum.com/forums...y-427-day.html ) and a lot on my profile. Let me know if you want to see something specific and I will be happy to post. Looks like you are only about 50 miles from me. Hope to run into you at the large car show in September in Gaithersburg (if they have it this year). There were too many shadows for a decent picture but here is a quick one (sun was going down) of the 245's from a low rear shot. Take care and stay safe out there. C.J.

 

I don't have offset arms so I had to relocate the parking brake, the largest tire I could fit with a 15 inch rim was the 235/60R15 in the rear, what mods did you do to get the 235 to fit the front?

 

I switched to a 1968 Rally Wheel (7 inch - one year only) in the front in order to accommodate the wider tire and I sanded down (from the inside) the half inch lip of fiberglass at the inside/top of the wheel arch.