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Hates: Liver. Loves: Diesel
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Discussion Starter · #1 ·
Started tearing into my 67 LeMans convertible project. Headed in a sorta pro-touring vein; Body will remain mostly stock, custom interior, 500-hp LS6/LQ9, T56, insert axle here (maybe a 9" if the one I have isn't too narrow)

The vehicle itself has 276k on it, and the frame has had a rust repair done. It's mostly a wet noodle, so something needs to be done. At bare minimum I'm thinking brakes and a refreshed/upgraded suspension, but there is also the option of big-dollar aftermarket stuff.

I don't think I need to go full-on Schwartz chassis since I've never needed 1G cornering, and since this is also going to be something I want to actually drive whenever I want, I don't want unobtainium/expensive parts. For instance, I would rather have some LS1-era F-body discs up front and off-the-shelf brake parts out back on an 8.8 or 9" so I'm not ordering Brembo or Wilwood every time I need to do maintenance. This will be a driver, not a HPDE or trailer queen. (Ok, maybe some HPDE stuff) I want to be able to drive cross country with it, not hide it in a garage.

Do I get an aftermarket frame, or try to stiffen up a stock frame?
 

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Race it, Don't rice it!
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AFCO makes a nice aftermarket version of those that you jig up and weld together so that might be something to look at for repairing yours.
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #3 ·
I had seen that, but they only list 68-72. The 64-67 were specific, especially when it came to convertibles. Any insight?
 

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Two things: First I like your statement about using "off-the-shelf" parts. While on a road trip replacement parts are just around the corner and not have to be flown in. Second, can't build a house on shifting sands. Rather you get an after market frame or repair, upgrade, fix and paint you will never be happy unless you have a sound "foundation".
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #7 ·
Techinspector, thanks for that resource.

39 master, I agree. I can engineer a decent suspension geometry and I'm an above average welder. I'm just curious if I can get any significant additional stiffness from modifying a stock frame versus the weight savings and rigidity of an aftermarket frame.

I have already spoken with Schwartz and they are very eager to help out with parts choices if I decide to buy just a bare frame and put my own components on, but even just the bare frame is $8000-10,000. I'm hoping for a middle of the road solution. I don't need the 1G that Schwartz frame can offer, nor do I want a $10k price tag. I'm hoping for a $5k price tag and a good, solid improvement over the wet noodle I have now.
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #8 ·
Just got off the phone with AutoWeld. Fantastic resource, but he said that since they've never done that A-body, I would have to absorb some of the cost of making the jig and he quoted $15-18k since it would be a complete custom job start to finish. We both agreed that they were more toward the Pro Street, Mustang2 end of the spectrum and I'm more on the Pro Touring, C4 end of the spectrum.
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #10 ·
Welll… I have the welder and I can build a jig with some wood, but I can't duplicate mandrel bends and the R&D that goes into an aftermarket frame. I also have a one-car garage full of motorcycle and tractor. Suffice it to say, it's worth $5k or so to upgrade instead of starting from scratch.
 

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I passed the thread title over because I do body work at a shop that puts various aftermarket frames under various bodies. Finally read it though, and I think I may have something to add without anyone yelling advertising.

First off, be it known that few whiz-bang new frames "bolt up". Bodywork required. That being said, the fact that you have a 67 LeMans convertible made me think...

A job came through a few years back which is pretty much your exact scenario. Last time I knew, and I don't know the current owners, they were calling it the Sugar Shack GTO (a 65 convertible) and it was every bit of a quarter million dollar build if not more, but we were the shop who finished it, and it came to us with a frame which might interest you already under it. I have plenty of pics, but the idea seed may be all you need.

They took what I would call the stock torque box corners... basically just the curved kickup areas, and built onto those. Seems like an easy way to go about what you're after. You can fix and reinforce the reused sections to the moon if you like but they keep the stock dimensions in place and you are free to graft on what you wish.

Of course, this puts your car down the whole time. Unless you can find a suitable donor frame. Since you have read through the whole disclaimer part now ha ha, I will see about digging up some images. I think there was quite a bit of overkill on it but am no chassis designer. Stand by for a couple inspo pix.
 

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Capt Mike
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If your frame is reparable, I can tell you from experience it will probably be less expensive and less labor to repair it and bracing. But, it'd really nice to work with an all new frame and set up everything without any mods to a frame.

AME (Art Morrison Enterprises in Fife WA) will Fab a perimeter frame or frame rails. They have quite a large selection.

I sent a CAD drawing to Brock @ Art Morrison Enterprises in Fife WA and they bent my Frame Rails for my '37 Chevy Coupe build to our Spec, was less than $1K with extra tubing sections. I chose C4 Corvette IFS and got my front cross member from Don @ Flat Out Engineering in Orange CA. The rear suspension uses the C4 Spindles and Dutchman's 9 inch IRS Center Section.

I have some experience with the Corvette C4 IFS & IRS, and I had a bunch of the components on hand. AME also bent my Roll Cage pieces. All where just about as perfect as can be had. Making the Frame Extension for the Body mounts was relatively simple.

As shown in the photos the frame rails are a work of art. We TIG welded on a frame table loaned to me by a friend.

IF your a DIY Guy and can at least tack weld, TIG Pro's can be found that will weld on location.

Michael..
 

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Chassis

FWIW department I build my own frame for the '39. No blueprints were available so I plumpbobbed the outline to the ground and made a set of drawings. Got two sticks of 2" X 4" 11 gauge and went at it. Turns out the frame was very easy to build and would recommend it to anyone who can fab. The finished product will not be as nice as a mandrel bent $10K frame but for under $500 and tucked up under the car it works just fine.
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #15 ·
If your frame is reparable, I can tell you from experience it will probably be less expensive and less labor to repair it and bracing. But, it'd really nice to work with an all new frame and set up everything without any mods to a frame.

AME (Art Morrison Enterprises in Fife WA) will Fab a perimeter frame or frame rails. They have quite a large selection.

I sent a CAD drawing to Brock @ Art Morrison Enterprises in Fife WA and they bent my Frame Rails for my '37 Chevy Coupe build to our Spec, was less than $1K with extra tubing sections. I chose C4 Corvette IFS and got my front cross member from Don @ Flat Out Engineering in Orange CA. The rear suspension uses the C4 Spindles and Dutchman's 9 inch IRS Center Section.

I have some experience with the Corvette C4 IFS & IRS, and I had a bunch of the components on hand. AME also bent my Roll Cage pieces. All where just about as perfect as can be had. Making the Frame Extension for the Body mounts was relatively simple.

As shown in the photos the frame rails are a work of art. We TIG welded on a frame table loaned to me by a friend.

IF your a DIY Guy and can at least tack weld, TIG Pro's can be found that will weld on location.

Michael..
I have given considerable thought to what you suggest. I was thinking of basically bucking a stock frame on the floor, welding in some center ladder parts, then cutting out the heavy parts on the perimeter and welding in some 2x4 tube. I have no idea if that would be any good (not a real engineer but I play one on TV).

The real draw to something like a Schwartz frame is that it (at least claims) 100+ lbs lighter, 200% stiffer, and requires zero body mods. (unless you want to tub it to fit 345mm.) I guess it's a question of whether or not I'd rather open the wallet and capitalize on someone else's engineering, or if I want to take a $500 chance on trying it myself.
 

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Capt Mike
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curtis73,

Had to say ,, not having seen the condition of your frame and suspension.

But, if you can dish up the 10k$ for a new frame and your a little hesitant and never completed a full frame build, might be a good idea,,, if you can't fix your frame or find a good used frame, DO IT.

As My Dad always told me and my friends,, The most important single area in any car frame is the front suspension, the rear is an easier choice. Most will never or can tell the difference between a custom frame and a good OEM frame in a Street Rod for a driver., it's really about whats up front for good comfortable and safe driving.

I tell my friends to either get a easily repairable frame or buy one if they don't have the experience and tools. I've assisted with long time friends in building frames and a whole long list of mods and suspensions swaps. But this is best learned along a long path of hands-on experience.

I have the advance of being a retired Engineer with years of this sort of Fabrication. And my Dad and a few family members who where also Engineers with their Street Rods. Growing up in and under Street Rods build by Engineers make a large difference in my thinking process. My Dad's driver was a '55 Poncho Safari Wagon and Mom's a '55 Olds 98. He build many Street Rods, was a passion. He drilled int o my head, do the research and do it once, correctly.

In my current build I was able to borrow a friends four rail frame table and then another friends car rotisserie. A frame table is mandatory most of the time, even a simple four beam box framework made from 2x4 steel would a blessing. Fabrication of a custom frame is not a few months of part time work, it is a true challenge. My current '37 Chevy Coupe build is a frame up with a full roll cage for safety and just because, but the body is a Carbon Fiber body and these don't come with any inner structures nor plans. So let me tell you that the frame was fairly simple, not my first. But the planning for everything else needed to bolt in suspension, running gear, steering and what makes a car was a huge challenge. And that's about what anyone's very first frame fab would feel like.

The main concern of mine with any custom frame anyone purchases from a builder are the "Got Ya's" The other area of parts that are needed to make a Rolling Chassis,,, suspension components for one.!! There are lots of frame fab shops, some better than others. But if their front suspension, for example, Brake options are often limited to the Big Companies, the buyer best have deep pockets.

I like the C4 Corvette suspension because the custom front cross members can be purchased at a very reasonable cost and pretty simple to weld onto frame rails. And that's what I did.. The C4 suspension has many strong points, great IFS anti dive during hard braking . But the biggie is you can easily bolt on C5 / C6 front caliper front calipers @ $250. Wilwood has their 1.25 thick performance rotors that are slotted and dimpled for $100 each. Try to find such large dual piston calipers anyplace else for $250 a pair. Great for DIY builders

One of the things that I like about AME, is they do utilize the Vette parts. The C5 / C6 Corvette IFS, a great low cost suspension. and low cost ancillary parts, Rack, calipers, coil overs or air bags.

And any frame maker can supply a 9 inch housing, so there no worry there with high price additioal high $$ components. And many makers of the 3rd members with a large host of gear ratios, and other options. I'm using a Dutchman's IRS aluminum housing with a 9 inch 3rd member. It was a PITA to Fab all the parts for the rest of the IRS, but I was set on an IRS setup.

My point is that here are many options, So try this,,,

Select a few frame suppliers and price out their base frame and with suspension, have them email you a complete build sheet and the cost.

Then complete a list of ALL the parts and pieces needed to make a full DONE rolling chassis. Now you can compare.

If need more help, send me a PM and we can exchange info. Happy to assist..

Michael..
 

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My father has a 65 skylark convertible frame off the chassis. One of those back burner projects.

I dont know if it was boxed from the factory or not. But this one is and is more then strong enough. Brakes and suspension upgrades are things you can fabricate mounts for later. Fix the frame.

In a driver I perfer drums easy to run, service, and cheap. But I also drive old cars/trucks like a old car/truck. I dont use the brakes much in a cruiser. But I do try to leave enough room(usually by passing) to stop in what I know it takes (usually 150-200ft).


Fix your frame, get the body on, electrical, drivetrain, interior, etc. It is a long and costly list as it is. Finish it.

Once the thing is driving down the road you can decide if the suspension and brakes are adequate or need to be upgraded.

Dont let a upgrade be the projects wall that stop the build for years.
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #19 ·
You guys are full of good advice.

I'm currently chatting with Schwartz about non-Brembo/Wilwood options. Initial discussions have been positive... that is to say, with careful ball joint/front arm choices, they can get nearly any knuckle I want in there. I do get the feeling however that I'm ordering an F1 chassis and then putting street parts on it.

I can find good, rot-free frames for $500-750 on the used market. Careful inspection of mine shows that it has a large rust hole at the driver's side rear kickup that was repaired with some steel treadplate. It looks strong-ish, but the 270k-mile frame plus rust plus 40-year old ragtop body is just floppy.

So maybe I do a mix of suggestions? I'm not happy about a $10k expense for a frame, nor do I think I have the skills to fab a complete frame myself. I think I DO have the skills to modify a stock frame, but I would need some significant education. Michael, I'll be PMing you.

Looking at the track width for C4s, it looks like they might be a bit wide for my LeMans unless I keep the high-positive offset wheels which I'm not keen on, but I'll research it a bit more.

Seriously, if I can buy a good frame, jig it up, and weld in stiffening and a C4 front cross, that might be the way to go here.
 

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Hates: Liver. Loves: Diesel
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Discussion Starter · #20 ·
My father has a 65 skylark convertible frame off the chassis. One of those back burner projects.

I dont know if it was boxed from the factory or not. But this one is and is more then strong enough. Brakes and suspension upgrades are things you can fabricate mounts for later. Fix the frame.
Mine is mostly boxed, not fully. I think that was the main difference with the convertible frames.

In a driver I perfer drums easy to run, service, and cheap. But I also drive old cars/trucks like a old car/truck. I dont use the brakes much in a cruiser. But I do try to leave enough room(usually by passing) to stop in what I know it takes (usually 150-200ft).
I don't mind drums, but I prefer disc. Plus with the 550-hp I'm putting under the hood and the potential for HPDE every once in a while, discs just make sense. If I'm going to have the potential to go fast, I want the potential to stop fast.
 
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