Hey guys,
I've gone through the search process and didn't really find what I was looking for.


I've got a '67 327/PG with a 10 bolt non posi. I've been trying to find a good (non expensive) 12 bolt posi rear end to swap in, but I keep missing them. So I've seen a few "how to build a bulletproof 10 bolt" and think that might be enough for me at this time.


My question is this: I have the mono leaf rear suspension. Is there a good, strong mono leaf spring I can use instead of the multi pak springs?


I've looked at the "Split springs" and I'm wondering if that's it? OR do I just go down and have a spring made?


Eventually, (Next Winter) I've got a 468 motor in the garage that will go in this car. I don't want to do the suspension stuff twice. I'm hoping I can just take my 10 bolt out, but a posi unit, add good axles, slap on disk brakes and call it a day for the rear.


Any help would be greatly appreciated. Since this car is all stock and a numbers matching car, I have a blank canvas and would eventually like to have a nice high powered, good handling, decent riding car.


Future plans are a 550-600 hp 468 with maybe a 700r trans and a 3.55 - 3.31 rear end. 2" lowered frt & back. Nothing special, just a fun car to jump in a go.


Thanks in advance.

 

JC Whitney used to sell a 3-leaf replacement spring.
Eaton Spring sells a replacement spring.
If lowering, look into sponsors here for suggestions.

You will need to get some new J-clips for the front spring eye mounting brackets as I am sure, without a bent box-end wrench made to hold the nut on the clip, you'll be cutting off the heads of the existing bolts then digging out the remains inside the frame member.

McMaster-Carr sells a pkg of 25, I think, and they do not look like original, but well hold 30 ft/lbs of torque and do the job.

One post:
rear leaf front mount picture of J-clip slots - Team Camaro Tech

Post 43 of 108:
Please Read. Sub-Standard leaf spring clip nuts - Page 3 - Team Camaro Tech

 

Everett#2390


Thanks for the information. I was unaware of this issue as the last build I did was a '91 S-10 Blazer. Dropped it 3" all around and didn't have any issues with the J-clips or bolts. But, that was only a 23 yr old car vs my 50 (almost) yr old 67.


I will do some more searching to find the leaf springs. If money was no object I'd consider a multi link set up, but not really interested in building that kind of car this time around.


Thanks again for the info. - Looks like I've got some good reading to do this weekend.

 

You're welcome, Mike.

Who knows, maybe the S10 J-clips can still be gotten from any GM dealer and those would work?

In the route taken, use antiseize - you'll appreciate it later in life

 

anti-seize for sure. Funny thing. I've bought like 2-3 tubes and packets of anti-seize and never seem to use it. But on this project I'll be using it for sure.


I know after 49 yrs it wouldn't matter much, so I'm expecting to have to fight with everything to get it apart, but I only want to do that stuff once.

 

What is your main concern, twist from the engine torque? When I had my first '67 I put in a stout 355, at the drag strip they said my car looked like a dog that had been swatted in the rear end with a newspaper. Under acceleration the back end dropped. The front left wheel almost came off the ground. Weight transfer and traction suffered.

I solved the problem easily with a set of traction bars, the good old "slapper bars" extended to the front spring bracket. With this, the car was TOTALLY different. The entire car now lifted together and lurched forward. The traction bars planted the rear tires into the launch pad.

 

This is a good article, these are what I used.

Episode 41 - Traction Bars - themusclecarguy.net

 

Coach62
Thanks for the reply. Yes, I've heard that if you put a good hi hp motor in there the rear springs would "wrap up" and get squirrely. I'll check that article out, but I was planning on using some traction bars. Actually the Caltracs set up. (Maybe) but if slapper bars will do the same thing, then that might be the thing too.


I just picked up my FRBK-BB Big brake kit from CPP this weekend. Much bigger than I was going to go, but got a great deal and had to jump on it.

 

My question to the OP is this, why do you want a mono spring?
Just because it was what the car came with?
If future plans are to put in a 468 with that much HP, those factory mono springs are not going to hold up to well.
I know what my 408 BBC was like, and that was about 500HP and if I was you, I'd be stepping up to a multi leaf, maybe a 4 leaf spring like what was on the Z's.
As for the CPP kit, I got one of their kits and they are nice!
Good luck

 

Stay away from those crappy clamp on slapper bars, they put stress on the leaf springs in front and back of where they mount to the axle. Use the bars that incorporates a lower spring plate, which attaches them directly to the axle housing.