Tubular rear subframe - Input needed

[99gst_racer]

Yup, same concept. Although the only studs that I've been able to find at work were way too large in diameter. They're Chevy/Ford circle track stuff. Got a line on a stud like that that will fit the 2G rear knuckle?

 

[Andranik]

Price and eta ???!!!

 

[greengoblin]

Another thing to check is tie rod ends for the s13/14 .

Like these: SPL Parts PRO V5 Outer Tie Rod Ends S13 S14

You might be able to purchase just the center adjustable pin from a company if you by a few in bulk.

I'm sure with a call you get measurements and maybe even by a replacement pin. to spec out.

Just another idea.

Edit:

It' looks just like stuff above only I know the s13 stuff is smaller. I'm not sure if it is the right size though. Also megan Megan racing makes so tie rod end for the 240 that are cheaper that might be good to try out with out spending much.

Kevin

 

[snowborder714]

Not sure exactly what you're looking for, but have you looked at Midwest Control Products? That's where Eric and I got the stuff for our sway bar end links.

 

[jdsoza]

Paul that is looking sick. Did you happen to find a way to get adjustable pickup points for the rear?

 

[greengoblin]

Paul that is looking sick. Did you happen to find a way to get adjustable pickup points for the rear?

There are two holes for both inboard pickup points in the pictures. So yes.

 

[jdsoza]

There are two holes for both inboard pickup points in the pictures. So yes.

haha thanks man. i drove all through california all night so when i saw these pictures they made sense but dint make sense

 

[talont3t4]

Looks killer

 

[99gst_racer]

Another thing to check is tie rod ends for the s13/14 .

Like these: SPL Parts PRO V5 Outer Tie Rod Ends S13 S14

You might be able to purchase just the center adjustable pin from a company if you by a few in bulk.

I'm sure with a call you get measurements and maybe even by a replacement pin. to spec out.

Just another idea.

Edit:

It' looks just like stuff above only I know the s13 stuff is smaller. I'm not sure if it is the right size though. Also megan Megan racing makes so tie rod end for the 240 that are cheaper that might be good to try out with out spending much.

Kevin

I called these guys and they want $49.95 each just for the studs alone! That's really the only part I'd be looking for as I have the rest of it in stock at work.

I did find a tie rod end from Allstar with the proper sized tapered pin, but I'm going to continue to look for something a bit smaller.

Allstar Performance - racing and high performance car parts, accessories and specialty tools.

 

[2slow4utsi]

So did you say you don't need to run the boston hatcher mounts with this sub frame? Also, any idea on exact weight and pricing? Interested to see the final product.

 

[99gst_racer]

Glad to hear you say that!

On the chromoly vs. mild thing. I know it's beating a dead horse per se', but, I just wanted to hear your reply to this:

I've got a local acquaintance that has been fabricating for the better part of 30 years. He builds some of the sickest roll cages I've ever seen. More recently on some time attack Subarus. He prefers mild steel as well. Not sure he's said that Chromoly is weak, however, a term like "brittle" was used. He says the main reason is the WELDS not neccessarily the tubing or wall thickness. And, this is a guy whose welds look like they were done by a robot. With that, he's also involved in the Rally scene where cage strength is paramount over weight reduction, etc.......

Thoughts?

Second, I know of a local car that within the last year needed to have it's chromoly cage stripped from the car, and have mild steel installed - to pass tech inspection for SCCA competition.

So, everyone has opinions, but with my above examples......there's SOMETHING up with Chromoly use........

Again, a bit off topic, but, thoughts?

Hey Phil, sorry for the late reply. I've been busy busy!

4130 chromoly VS. 1018 mild will always be a debatable topic with an indefinite answer. I feel that both materials make for excellent chassis components in the automotive world. 4130 gets the advantage for being stronger/harder, and so can be used with a slightly thinner wall thickness to save weight. 4130 is a heat treated version of mild steel that has about 2.3% of alloys added to it, so aside from that, there's really not much difference between the two.

4130 isn't one of those materials that just anybody can jump into properly using. It's not difficult to learn but it does require some extra effort to do properly. When a 4130 part fails, there can be a dozen reasons why, as well as ways to prevent it. Some people use 4130 filler, which requires heat treating afterwards, otherwise the part can be too brittle. Some people have poor fitting skills and crank up the amperage and use a larger filler to fill fitment gaps. This inadvertently puts way too much heat into the work and can weaken the heat affected zone outside of the bead. Other failures can come from guys that use too thin of a wall thickness for the part, or don't stress relieve parts that need it. Generally though, if a 4130 structure fails, it either wasn't designed to be strong enough, or it wasn't fabricated (fit, welded, etc...) as good as it could have been.

For example: the landing gear of some small airplanes uses heat treated 4130 material. If they used mild steel, it would have to be a very heavy wall to compensate and it would add unnessacery weight to the craft. But if they used regular thin-wall 4130 material, it would probably eventually fail. So, they heat treat 4130 to increase its yield strength to around 200,000 psi, which results in a product that is lightweight and strong enough to handle the specific type of abuse. Material selection is all about overall goals and uses, so there never is one universal answer between 1018 and 4130.

The issue of it being brittle refers to the HAZ. Reducing the ratio between the temperature of the welding and the temperature of the work can really help here. This is why many fabricators pre-heat 4130 prior to welding. Also, using the least amount of amperage to obtain fusion and penetration helps immensely. Many longtime and skilled welders can't even get that right and they just throw a ton of heat at it "just in case", not understanding how they could be weakening the structure. In case you haven't already read it, check out my post regarding TIG welding 4130.

One common misconception of 4130 is that it's harder, so it will break, whereas a similar mild steel part would simply bend and stay together. This is completely false provided the part was made properly. While it's true the 4130 is substantially harder and stronger, its level of elongation before breaking is actually about 5% higher than that of 1018 mild. 4130 will stretch more before failing. Also, their elasticity (flexibility) properties are almost identical. So, 4130 has a higher level of toughness to resist cracking, as well as excellent elongation properties to be able to absorb energy and deform without breaking.

In short, I like both materials and I'm a big fan of 4130. I just feel it gets a bad rep sometime due to a lot of misconceptions floating around. IMO, design and craftsmanship are far more important attributes than material selection with something like a subframe.

 

[greengoblin]

I called these guys and they want $49.95 each just for the studs alone! That's really the only part I'd be looking for as I have the rest of it in stock at work.

I did find a tie rod end from Allstar with the proper sized tapered pin, but I'm going to continue to look for something a bit smaller.

Allstar Performance - racing and high performance car parts, accessories and specialty tools.

Ouch. Was that for one ? I guess they weren't saying much about where they get them from either.

 

[greengoblin]

Also the problem with some of those other tie rod ends like you pictured is they are HEAVY.

 

[greengoblin]

PDM Racing - Suspension

 

[99gst_racer]

Also the problem with some of those other tie rod ends like you pictured is they are HEAVY.

I just weighted it. Came out to 17.7 oz. It's not as light as I'd like, but it sure is affordable.

Ouch. Was that for one ? I guess they weren't saying much about where they get them from either.

Yup, for one. He even chuckled knowing that I wouldn't pay that price.

It sucks too because the larger diameter studs are plentiful at about $15 each.

I currently use a Howe joint on my car for the toe arms, but I had to ream the spindle to fit. I assume most people wouldn't want to ream theirs, nor drill out the taper.


EDIT: I just found a bump steer stud here at work that should fit!

 

[greengoblin]

Nice. Glad you found something. That will also make building a bump steer kit easier. PM with info on it once you make sure it will fit.

I here you you about reaming the hole. Most people would not want to do that or pay for a good reamer.

Also I'm going to start pulling my x-memeber to ship to you this weekend.

 

[99gst_racer]

Schweet!


Here's the plan. It's a bump steer stud that bolts into mono-ball, which will bolt up into a housing that gets welded to the tube. The housings are out of stock until next week, so this is all I have right now. This should weigh about 7-8 oz. less that the tie rod end I posted above.

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[jw4free]

Wow. I love it. Serious attention to detail, parts selection and end user fitment.

 

[greengoblin]

That is great. Why did decide to use a bearing and housing over a rod end Paul?

 

[99gst_racer]

That is great. Why did decide to use a bearing and housing over a rod end Paul?

I originally assumed that a bearing and housing would offer more (needed) misalignment. But on second thought, I'll also pick up a rod end and find out for sure. A heim sure would be cheaper and easier if there isn't a binding issue.

 

[greengoblin]

They make some high misalignment rod ends that should work just fine I'd think Paul.

 

[99gst_racer]

I found a teflon-lined, heat treated heim that offers 26* of misalignment, which will be more than enough.

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I'll have final pics of the assembly tacked up by tomorrow night. And we'll start welding it all together on Saturday.

 

[greengoblin]

Where was this part when we built our toe arms Paul! That is great looking.

Kevin

 

[fjm9898]

Awesomeness. keep it coming.

 

[99gst_racer]

I got the last bar bent and fit underneath the pinion. My next pictures will be welded up and out of the jig. Time to get started on control arms and toe arms!

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