Torsion bar/K frame question

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Inspector71

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This is still a little way off but I'm trying to get an idea of the parts I'll need for my project. It is a 68 Barracuda that had a slant six/auto trans. I plan to swap a 360 in using Schumacher engine swap mounts. They strongly advise upgrading the brakes to discs and I get that. They also advise upgrading the torsion bars. Are the ones sold for 68 A bodies through Mancini/Summit/etc. the right size? Will there be any problems attaching the larger ones to the slant six K frame? And, while the engine is out, should other upgrades be made to the front suspension and can they be done in a garage? I have little idea what I am doing, got tired of the car sitting year after year, and decided to just do it guided by you all. Thank you all in advance for the help you've given me.
 
I have 1.03" bars in my small block '70 Dart. Was a /6 and put stock 340 bars in it and still not firm enough for my liking. I would go with the .920 bars at the very least. I ditched the 9" drums for some 10" ones I got for free for helping a buddy install his bbp discs. The 10" drums work fine ONCE with regular linings. After a real hard stop they will fade unless you have the high performance shoes for higher temperatures.
 
MischiefDart: Thanks, that is exactly the kind of information I need. I know nothing about suspensions but figured the plan to just swap a motor was not realistic without other changes. You stayed with drum brakes? I drove them for years without anyone real problems. Again, thanks for the reply.
 
a-body torsion bars are a-body torsion bars just different diameters for different rates. Putting disc brakes on it is a damn good idea. Trouble is the large bolt pattern stuff, think later cars, is A LOT cheaper than the small bolt pattern stuff.....If you go with the lbp stuff you will need to change the rears as well, unless you are not going to carry a spare tire then who cares? Firmfeel sells re-enforcing plates for the lower control arms that might not be a bad idea, as well as finish welding up the k-frame.....again dependent on what you are doing....
 
MischiefDart: Thanks, that is exactly the kind of information I need. I know nothing about suspensions but figured the plan to just swap a motor was not realistic without other changes. You stayed with drum brakes? I drove them for years without anyone real problems. Again, thanks for the reply.

We have all driven drum brakes in the past, but with how many complete morons are on the roads now-a-days I can not imagine doing it in the present day. A friend just tied his drum braked Nova into a knot a short while back....much to my surprise he did admit that if the car had discs it might not have happened. Drums can be made to work well, but I would have to consider that throwing good money after bad....But only you know what it right for you so.....
 
Yes I am running the drums for now. Inkjunkie is right about discs having better performance. The biggest problem with drums is if you are using them hard repeatedly you never know when they will fade and just stop working. Firm feel sells sintered metallic linings for the drums to help with the fade problem. I like the 10" drums on my Dart. They have good pedal feel and stop well. They also keep me from driving too crazy because I know they will stop working if I heat them up. Been there done that with my '72 challenger I bought as a teenager. Basically for regular street driving the drums are fine if you are going to be tearing around all the time get yourself some discs.
 
Hope you get another 68 on the road.

What plans do you have for the car? Is it going to be an updated stocker, a drag oriented car, an all-around good handler? Definitely do the disc upgrade because you'll be out there driving among modern cars w/ ABS, brake assist, skid control, etc. No matter how careful you drive, it only takes a second for a texter in a Lexus to do something stupid and get you in trouble.

My 68 is a Driver. LBP 73-76 A-body discs, 10 x 2-1/2 B-body rear drums on an 8-3/4 w/ resplined/shortened C-body axles, manual brakes using a Direct Connection 1-1/32 bore aluminum MC, adj. prop. valve, 15 x 7 steelies, (4) 215-60 x 15 Kumho radials, .92 front T-bars, 73-76 spool mount K frame, reinforced LCA's, Moog offset UCA bushings, Moog rubber front end parts, poly sway bar bushings, HD rear ESPO springs w/ poly bushings, 16:1 manual steering. Before it hits the road again in the spring, I'll have the DC oval track rear springs and the frame connectors installed.

Whew, all that took awhile but it was many small projects over the winters keeping it drivable for most of the summer. And I probably drove the car 5 years (in summers only) with the BBP in the front and SBP in the year. No big deal and I don't have a jack in the car anyway. This car is so solid, it feels like it weighs 5000 lbs sometimes (actually around 3230) and tracks like a freight train, but it goes where I want and stops when I want.

The 65-72 K-H discs are good (and Summit has vented rotors) but you'll be generally limited to SBP wheels. Since your /6 car more than likely has the little 7-1/4 rear, you should be looking for a heavier duty rear end. (8-1/4 or 8-3/4) I think your very FIRST decision is which bolt pattern?

My advice would be to make a plan, collect the parts, and make it happen.
 
Hey thanks for the great advice. You've convinced me I really need to go with discs. That would mean the bigger bolt pattern right? Can I still use 14x7's? I really like the chrome rallye wheels. Like I said, I've had the car for many years, been in storage, and have no idea what I'm doing but I like learning and I like working on my old cars.
 
More great advice. You are not exaggerating about how bad driving is. I have a small car now and I can't believe how many people run stop lights, pull out in front of other cars, you name it and so many are texting. I plan to have a 360 rebuilt with more hp for an all around car. I don't plan on drag racing but I'd like it to have some muscle on the street and handle well too. It is still down the road. I'm going back and forth between a 3.55 or 3.73 rear gear set. Street driven mostly. I might take it on the highway to St. Louis but that would be about it. Stop light car I guess is what I'm saying. Fun fun fun

Your car sounds they way I want mine. I don't have a lot of help, okay, none right now, but I've gotten a lot of great help on this forum from you all. For example, I was thinking about staying with the small bolt pattern because I can get the chrome rallye wheels at a good price. But then, I started looking at the rear swap I need to make, the need for disc brakes, and that idea fell apart real fast. That is why I'm asking these questions. The slant six/tranny/ and radiator are long gone, the car is excellent shape bodywise, and it might be the right time to set up all the suspension stuff before I start messing around with engines and all that...
You all have gotten me back on the right track. I am dying to get into this project and get this car on the road. Some people don't get it but I'd climb over a forest of corvettes to get a look at an A body any day.
 
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