I am checking for interest in a replacement Front Upper and Lower control arm setup with replaceable ball joints. I am working with a company and it would be cost effective way to have a great part with serviceable items. If there is enough interest I will proceed with moving forward. Pricing hasn't even been determined but substantially less than OEM is for sure.

 

im interested

what would the arms be made of?

 

It will be great with camber adjustment too.

 

Would they be milling oem arms to take aftermarket ball joints or making compleat new arms

 

Others have proposed this very same plan, but I have yet to see anything materialize. This is the closest I've seen so far: https://www.rx7club.com/group-buy-pr...oints-1061125/

 

Wouldn't be a fan of "strong" wishbones as per the 7075 ones. Stock ones will bend with a reasonable impact, minimizing other damage.

If you find a car won't align one side to the other (nearside kerbin' fer instance), might find they're bent....not visible to the naked eye.

 

These would be all brand new set-up. Tubular and adjustable. Would be similar to the V8Roadster setup. What I would need to get started is a Left and Right LCA and I should only need 1 upper. To get good solid measurements and have it ready to go into prototype stage.

So if anyone has an old STRAIGHT set laying around................

 

I might have a set have to dig through the parts pile and bins

 

These control arms are still on the table but we didn't get enough solid interest to move forward with production.

Price will be $1200 a set and if you're serious about getting a set of billet adjustable control arms and are willing to put down a $600 depsoit, Mark's Engineering will make it happen.

 

Those look cool, but I don't see how that's cheaper than stock, I think I got all four front arms for not that much more than that.

I'd warn against a full hiem joint suspension on anything but a pro race car. Most of the track guys still run some sort of isolated/rubber bushing, and they wear quickly as well. Realistically if you were to replace with new arms, they would probably last the life of the car as much as most are actually drive these days.

P

 

Wouldn't be a fan of "strong" wishbones as per the 7075 ones. Stock ones will bend with a reasonable impact, minimizing other damage.

If you find a car won't align one side to the other (nearside kerbin' fer instance), might find they're bent....not visible to the naked eye.

Your impact would have to strike the top of the wheel/tire in order to bend the upper front wishbone.

In my opinion and experience the impact is almost always on the lower wheel/tire area and transferred right though the very strong forged lower arm right into the bendy front "frame rails".

 

These control arms are still on the table but we didn't get enough solid interest to move forward with production.

Price will be $1200 a set and if you're serious about getting a set of billet adjustable control arms and are willing to put down a $600 depsoit, Mark's Engineering will make it happen.

Did your analysis show completing the triangulation at the inboard side wasn't necessary?

It looks like those would be super bendy under braking.

 

At that price, those control arms will always be on the table. Right this very second, you can go to Mazdatrix and get a SET of OEM stock front LCAs for about $1130 plus shipping. With that, you get a shiny set of brand new OEM LCAs with actual engineering behind them. As I stated in your interest thread, Mark's set are for the more show-off crowd (who would probably use OEM anyway). Aftermarket replacements for these must be comparable in performance and material, and be cheaper than OEM to make them worth mass producing for the few who would be willing to buy them over OEM.

 

for sprint races we have run full hiem joints, but any impact gets transmitted into the body/subframe, and as such the alignment moves around, because its bending stuff, slightly.

for enduros we either run stock rubber or poly, because it isolates impacts.

 

Can't say I've seen a top one bent, pick-ups either bend or are ripped off the body.

If you believe some of the past stuff on here, there's been a couple of manufacturing methods for the lowers. Can assure you the arms can and do bend, before the subframe and rail...having swapped arms to fix an incurable castor issue which had us scratching heads for a while.

 

Are these items still available...? How can I order one set?

 

Are these items still available...? How can I order one set?

 

If you are willing to spend that much on UCA vs buying good used, why not get these?

https://www.rhdjapan.com/nagisa-auto...rx-7-fd3s.html

 

Hi, Are you selling them? How much?

 

Fabricated suspension arms with welds/heim joints that haven't been stress tested would worry me. I'd rather see a service that simply removes and machines the OE arms to accept an replaceable/aftermarket ball joint, like the Moonface arms did in order to use a longer stud for roll-center correction.

The stock arms are fine, but the non-replaceability of the joint was really stupid/cheap. I wonder how many sets of otherwise-good arms there are out there because of it.

 

You buy them from RHD Japan as per the link I posted

 

Are those available?
I’m also looking for Front lower control arms.

 

I have Nagisa front UCAs. Tubular steel with hiem joints and no provisions for the wheel speed sensors so mine are attached with race car magic (zip ties). I am told by my local race car shop that stock LCAs better control camber, FWIW.