[J-Ville VR-4]

Its not that advanced tech, but this section of the forum is a little skimpy lately and could use some new topics.

I had lunch today with my friend Dan, who started a company that sells kits for mounting LSX engines into miatas. Dan and his partner Richard (both good friends of mine) designed and build all parts of the kits, which include a tube steel front subframe. Anyways, I threw out the idea of making a new front subframe for my car since I'm tearing it all apart now anyway, and he said he would be happy to take on the project. He knows his way around a 3/S - his wife owns one, and he has helped me out with my car and other 3/S's from time to time, so this should be no real problem. Dan has some cad software that he uses to design the subframes, so they are easily duplicated, which means he will be able to make more to sell if any of you are interested.

I started this thread to discuss what improvements could be designed into a new front subframe. I'll start out with the obvious: it will thankfully drop some weight off the front end of the car, I'm estimating around 15-20lbs maybe. It will be mild steel, chromemoly is not an option.

The control arms mount to the chassis, so I assume changing suspension geometry is out of the question. Would it be worthwhile into designing control arm mounting points off of the subframe instead of using the stock chassis points?

I'd like to provide a little more room in the rear to accomodate room for 4" exhaust to fit back there correctly, this shouldnt be a problem at all. Also, I will be sure to make this design much more friendly regarding the tight clearances involved when removing/reinstalling the transmission if possible.

The steering rack: Would there be any benefit to repositioning the steering rack at all? I thought I read awhile back that moving the rack forward/back affects the amount of ackermann steering a car will have, would it be beneficial to mess with this? I guess I need to dust off my old Carroll Smith books.

Engine mounts: I have maximal performance solid mounts in my car now, and I am very happy with their performance, so I plan on designing solid mounts into this design as well. I remember the stock motor mounts that bolt to the block are hideously oversized (isnt there turbo clearance issues with these for some TD05 guys?), I will consider making new pieces that are smaller and less obtrusive.

Bushings: The stock subframe has bushings, correct? I see no real need for bushings anywhere on there. I really wish I had my car torn up right now to the point where I can access my subframe better at the moment so I could be more certain about some of the things I bring up, but I'd rather start planning this asap.

Anything else anybody can think of?