Gauging Interest: Tubular Rear Subframe... 5 people minimum

As some of you know I'm building a racecar and R&D'ing some of my own parts. I'm going to be building a rear subframe jig shortly and am wondering if anyone's interested in purchasing a subframe and helping me to absorb some of the upfront expense involved with taking on the project.

I'm going to start this as a gauging interest thread and if the numbers come in were I think they will then the commitment I'm asking for from everyone is going to be roughly $1300 or so. If I can get a minimum of 5 people to commit, we're good to go and should be able to keep within $100 of that number. The more involved and pieces produced, the less the overall expense for everyone.

The $1300 estimated cost will cover a portion of the forum payment requirement, jig material and conceptual part construction, all custom CNC'd work for specialized pieces and laser cutting, 3d measurement for Q/C and possible solidwork loading for cnc laser tube cutting on future runs, and one powdercoated direct bolt-on stock replacement tubular subframe.

The subframe will be approximately 35-40% lighter than the OEM subframe and will be modular so you can swap from OEM mounted ends to FK Rod Ends or something similar. There will be no pics prior to purchase, this will be a build jig and go, so it's going to be a one time shot. A run of 5 and that will be the end unless future interests allow.

In the event the demand is there for another run, the 3d solidwork and design rights will be royalty to the original contributors and a royalty fee will be paid and distributed evenly to all parties involved in the first run.

It will take approximately 6 weeks to produce the parts from the time the last person signs up. I'll be asking for all setup, jig, 3D imaging, and raw material costs upfront. Somewhere around $300 per person for 5 people. I'll be asking for everyone to be paid 75% when the jig is complete and the conceptual frame is fitted on two chassi's which I currently have available. One is a stock 93RT-TT, the other is a 2nd Gen VR-4.

If you back out, the upfront R&D deposit is non refundable.

I will provide the actual production cost to all involved.

Additionally, I'll require a confidentiality and trade secrets agreement filled out and notarized if I'm abe to provide 3-D CNC images for future copyright.



That's pretty much it.

Soooo, Custom Rear Tubular Subframe

1) J. Fast

Looking/hoping for 4 more...

PM sent

Sigh... I wished for this years ago and now... I just can't justify it anymore. Good luck with this, I hope you get enough people.

1) J. Fast
2) Fearpb
3)
4)
5)


3 More...

All PM's answered... This is the real deal guys.

This would be great, but other mods call at this time. :(

Good luck

Its something I would look into the vr4, I plan a fair amount of weight loss for it.... Would be sweet if someome made one that bolted directly into a fwd car for a reasy awd convert... Justtt saying

You have a rough idea how much weight this would take off?

is this for front and rear?

Gauging Interest: Tubular Rear Subframe... 5 people minimum

Reading comprehension fail lul.


Get in on this Coop!

Thought hard about it, but... I have been side tracked too much from my plans as is...

This is one well worth being side tracked by.

It's going to drag my build on longer lol.

Sigh, I know. :sad:

It would also put a "Definitely Not Gonna Make It" on my might make NG hopes...

Thinking... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. ... ... ... ... ... ... ... ... ... ... ...

PM sent

oh lol how did i missed the rear lol.damn this is good deal. too bad my car needs an engine now and i just bought a car. i'll definitely get one, most likely on summer time.

ahhh!!!!! sucksbeingbroke!!!!!! J. Fast you have PM.

Wow, I want this. It's just so low on the priority list... Can't wait to see pics of this when people start installing them.

Do it Adam!!!

Interested to know estimated weight savings as I don't know what the stock assembly is to work out the %

If there is a front........ Our understeering cars would benefit more from the front tubular assembly surely.....or both!

André

The weight is an advantage but the real reason for wanting one is the unbelievable amount of adjusts you have now. Not to mention making all the rubber in the suspension go away.

My car will be a drag/highway car.

How do you see this performing for me Erron?

I think it would be just fine. For a drag car, the real benefit would be the weight. For us road guys it will be the adjust-ability and the lack of rubber.

:bump:

Alright so here's everything laid out so far.

1) 8 hrs of chassi probe work and tracing of front and rear subframes for solid work loading $750

2) 3R Racing Optimized Suspension Geometry Analysis $750

3) CAD design for front tubular subframe, control arms, and upright adaptation $2250

4) CAD design for rear tubular subframe, control arms, and upright adaptation $2250

5) Cost to build 5 full front and rear subframes, provide new control arms and end links, and a Moton, JRZ, Penske, or Bilstein upright adapter $6500.

6) Materials $2600

Total: $15,100

Split between 5 people and that's $3020 for a set. That will be for a front and rear subframe, control arms, suspension links, and upright adaptation.

$1510 for the rear subframe and $1510 for the front. That's as Real as it gets for a group buy. Sorry to say 3R Racing has a minimum and they won't touch it for less than that price as it's quite a bit below their standard minimum. I wanted to do just the rear for now but it doesn't look like the geometry will work unless you do them in pairs. The front and rear will need to be swapped out simultaneously.

If there is no interest it will be an as-build and nevermind.

Only 3k for f/r? Thats something i could find the coin for given enough lead time. Im primarily interested in the weight reduction and the suspension being corrected for being 2" lower than design. Will this still accept OE struts? Any estimate on weight loss?

Jason

Jason really has me thinking about this, interested in weight loss numbers. That is my real interest in doing this.

Same here, now sign up damnit!

Hmmm...

Is there a time frame on this?

The front suspension will be modular and will accept oem struts. Can't say on the weight for sure yet. A good guess is rougly 50lbs on the subframe, another 60 lbs on the uprights if you wanted to upgrade to billets, 20lbs on the suspension links and control arms, and 50lbs on the swap to a lighter shock. I would think a range of 150-200 pounds is a fair guess.

I'm open to the idea of waiting and can shop this around a little more. It's a big pain in the ass though as I have to load up a chassis on the trailer and run it around for estimates and evaluations.

No immediate hurry as of right now. I can rock what suspension bits I've rounded up in the mean time and enjoy them for awhile if need be. I will eventually require the ultimate though and will build just one, ore have someone else make several.

There's still a few things to sort out and a few questions and concerns I have with the setup myself. I'll get back to those when I finish a few other priorities I'm managing at the moment. I will keep you all in the loop when I talk with 3R Racing again next week and I get more feedback.

If you guys are wondering who I'm retaining for the R&D and building of the subframe, the company's called 3R Racing. Here's some of the cars they've built and campaigned:

1) Red Line Synthetic Oil - Road Racing - 3R Racing

2) SCCA Speed World Challenge Grand Touring Class - Car Comparison - Feature Article - Page 5

3) SCCA Speed World Challenge Grand Touring Class - Car Comparison - Feature Article - Page 3

4) Subaru WRX-STi Build for NASA Endurance Racing


Here's their website: http://3rauto.com/

They also have a shock dyne, dynamic suspension testing equipment, and a tracing probe and 3D part upload scanner. They're Pro's, building the best stuff is what they do.

HOLY sssSSStudder! lol

For what its worth, Nelsons subframes from NRG tech dropped 387lbs off his car.

Jason

I really can't say for sure how much weight it's going to save. That number from Nelson is absolute bullshit though and I'd say it to his face. I weighed everything. The front subframe only weighs 45 lbs and the control arms and shocks weigh 50/ The rear is roughly the same... The arms in the rear weigh 100lbs tho. The subframes and arms combined dont weigh more than 250lbs so how did he majically remove more than what was there? I'd love to hear how he did it... really! I'd laugh my ass off and bust out my scale!

Sign up Coop, Jason, and Dave!

Budget is tapped this year...

Those were the numbers from NRG tech, not Nelson.

http://forums.evolutionm.net/5573881-post25.html

Jason

Did a 200lb man get out of the car when they weighed it the scond time? I could see 120. Looks like I'll have to bust out my scale. For sure the front subframe weighs 45 lbs. That approaching 400lbs of savings number is absolutely over the top. Last time Erron came by my garage when I was pulling the subframe he asked me about building it and what I thought I could shave on weight. He mentioned cutting like 300lbs. I looked and him and said "you can't be serious? How much do you think the front and rear weigh?" He said atleast 100lbs in the front. I said "no fuckin way" and grabbed my scale and hopped on it holding the entire front subframe assembly. It weighed 45lbs. With control arms and all the other jazz mounted to it was still less than 80 lbs.

So if Nelson's using a stock LCA and the front weighs even 20 lbs less, that's only 25 lbs in savings. I'm surprised no one ever checked that number. I bet he swapped his CF doors and a bunch of other shit before and after, or weighed the car with someone in it and then without them.

The front and rear assembly's just don't weigh 450lbs. They weigh just over half of that. Those numbers are wrong, don't believe them. Raukuny is going to weigh his rear subframe that he's rebuilding, and I'm going to take mine to the scale at Bandimere to confirm, and then start asking questions...

It's absoultely ludacris to think that my racecar could potentially weigh less than 1000lbs with a full suspension, subframes, cage, seats, brakes, panels, and glass. That would mean it would weigh no more than 1800lbs with the motor and CF driveshaft. You saw the weight. it was like 1385 lbs with the stock subframes, brakes, suspension, cage, panels and etc...

I think they are also counting the front subframe connectors, front crossbrace/motor mount brace, rear trailing arms, and possibly some other stuff that NRG built at that time.