So I weighed a CA subframe and a stocker

[ProdigyCustoms]

There has been a lot of talk about subframe weights. I got a killer deal on a slightly used Chris Alston subframe I bought for my street / racer (straight liner). We had the motor out and was contemplating putting the subframe in also since the motor and tranny are out. Now this is not a bolt in this car, the factory frame is VERY welded in, so this would require total interipr removal, floor cutting, fule line routing. About a 80 hour job. So I got looking at the CA frame and started doing mental math. While it looked lighter, it just did not look 100LBS lighter. So we decided if the frame was 101LBS + less then stock (which would be almost 1/10th in ET) we would change it, otherwise it was not worth the time.

So we weighed a stock rolling subframe (no tires), factory disc, manual sterring complete. 317 LBS

We weighed the CA frame rolling complete (no tires), wilwood 11.75 Dynalite disc, manual rack, complete, 255LBS

So only 62LBS lighter.

I know this has been a question for quite a while, and Chris Alston does not know the weight difference. These are still very nice driving subframes, and for a no expenses straight liner project, or just a driver, a nice piece. But for us, in a shop back logged 6 months, not worth the time right now.

So now we know the facts.

[Charley Lillard]

OK mr tester... What is the difference in weight between the dynalite and stock ?

[baz67]

OK mr tester... What is the difference in weight between the dynalite and stock ?

Just what I was thinking Charley. I would be the brake weight difference would cut the total weight difference to somewhere in the mid 50lb range.

Interesting, thanks Frank.

[wendell]

Having picked up a dynalite and a GM single piston, I'd go even further andGUESS 40lbs. Another 10# for the steering box and it gets hard to justify the expense of a fabbed subframe. It's almost impossible to justify once you know how hard a stock clip can work.

[David Pozzi]

Frank,
Thanks so much for posting this info! It has long been debated how much weight was really saved. Much of any savings appear to be in converting to a rack and pinion unit, and lighter brakes. Some of the smaller Willwood calipers and rotors are lighter but don't brake as well as stock.
David

stock 69 single piston caliper with pads 10
69 knuckle assy with caliper 46
2 pc rotor 12
2 pc hub 6

[ProdigyCustoms]

I also think the majority if the weight loss is in the brakes, and box, like the rest of you. I will have to tear it down to see. My guess is 40lbs for brakes and the rest is in the box, center link, tie rods, etc. It only stands to reason, frame for frame they would be the same. It is just one of those things, I was looking it over and doing mental math, it just did not seem like it was going to be the 100 to 125 I had always heard.

[J2speedandcustom]

Interesting...nice work Frank. So if the weight isn't going to be an advantage. What about rigidty? Is the aftermarket better for the track? Or is it going to be the same. You can run a wider tire on the aftermarket so that's where the advantage is.

[ProdigyCustoms]

In our case, it would not matter due to other bracing, even if it is stronger.

[Mean 69]

Frank, that just can't be right. Everyone knows that the aftermarket frames are WAY lighter, and WAY stronger, there must be something wrong with your numbers. Just ask any of the hundreds of folks opinions on this and other forums.

I mean, come on, hard data? Pfff! Who believes that stuff? I know a guy, that had a brother, that knew another guy from down the street, and that guy said that the setup is at LEAST 150 lbs lighter, so, I mean, really dude, do you expect us all to believe hard data? Eghads!

"What about rigidty?" A very popular Camaro used an aftermarket frame that was allegedly stronger and stiffer than the stock unit, again, as everyone's opinion stated. The dude who built it, who is basically everyone's hero here, specifically told me that it was far less stiff than the stock unit, to the point of needing down-bars to keep it from noodling around. It wasn't an Alston unit. This particular car is one that everyone has seen, and is basically the benchmark for the hobby at this point.

Okay sarcasm off, but it is true that folks are a bit mislead by how much lighter the aftermarket stuff is. I can tell you though, after hefting several first and second gen front frames around that my back seems to like moving the first gen frames more than it like moving the second gen ones! I think Chicane has a complet list of the specific weights of all of the stock components, I also think I have a bookmark of second gen stuff that some one whipped up too. Might be a good sticky, or at least a good archive thread?

Mark

[wendell]

don't you have an upright you could be measuring?

For the record, the first gen subframes have been know to have rigidity problems after a few hours as the cathode in a muratic battery.:ssst:

[Steve N 69 69 69]

Cool, thanks for the info, I was always wondering about that myself. I wish I had a way to weigh the frames when I had them out.
Weight aside, I got my CA frame because I wanted to upgrade my worn out steering, brakes, out dated poorly designed suspension, all at once. when I added up the cost of all the individual parts from various vendors, the price of the CA frame, or the other ones out there, didn't seem too bad. Plus its designed to work as a unit, with none of the misfits or modifications necessary to make a bunch of aftermarket parts play well with each other. also, I'm running 18x9 front wheels with a 3" drop, and NO rubbing lock to lock, I havn't seen that on any stock frame cars.
So the weight savings to me is just a bonus. plus, dont forget to factor in the ...ooohhh thats purrrrdy... factor.

11533

[David Pozzi]

don't you have an upright you could be measuring?

For the record, the first gen subframes have been know to have rigidity problems after a few hours as the cathode in a muratic battery.:ssst:

Yeah, what he said!

[rohrt]

I see $1395 as the price. What does it cost fully loaded?

[ProdigyCustoms]

$5000 with brakes, I may have one for sale with hardly any miles, long story. I am trying to decide if I want to keep it around since I am not going to use it.