The ride height and exposed shaft length of where it sits now is all I really need to know. It’s more of a double-check to make sure I’m not overlooking something.

A bit disappointed that nobody else seems interested in contributing information lately. This should be a two way deal ...

I guess I’m missing the question... mainly because I have mine and I’ve shown the modification I did to make them work. You can contact lex and get an exact copy of mine if you want.. I’m not keeping any secrets with my setup.

Well I’m just trying to get some rear race shock reference position measurements. If you were to tell me the ride height from axle center to fender lip and the remaining rear shock shaft length (assuming no bumpstop) at that height it’d be sufficient. I know where the OE position is and I know where my Koni 28 shocks are relative to that. I think the Koni body might be a bit too short. So I’m considering going with a longer body to then also get more droop. Going to give up some compression travel in exchange, but at the anticipated higher spring rate I don’t think that will be an issue. A remote shock is always going to have a bit of a travel advantage with the divider piston out of the main body, but then most of those are using the shorter MX5’ish length and are instead limited that way to even it out some.

Pics with both inside wheels off the ground may look cool, but that’s the opposite of what I want to achieve.

Team, I'd get under my car tonight and take some measurements for you, but unfortunately my car is in another state at my codriver's house. Will be a couple weeks before I get it back.

I'm VERY eager to get new shocks on my car, and I just found out about this inverted MCS endeavor from RE-vision. Please keep me in the loop!

distance from axle center to fender lip could vary based on total tire diameter, shouldn't be much tho. my car is on the trailer and i could crawl under to measure but i have ohlins RT so i don't think i can even see the exposed shaft to measure it.

Actually I’m probably good, but if you want to confirm body length from mount bolt center and ride height it will give me another data point.

Axle center to fender dimension doesn’t change with tire OD. That’s why it’s a preferred measurement. Tire OD changes fender clearance and chassis to ground clearance.

yeah you're right.

Well Ohlins lists the lengths on their application-specific shocks, so not really any need for you to measure. I wasn’t expecting them to use a longer body length on both shocks (13-15mm) for the NC fitment. Being 500 lbs lighter is likely the reason

Sorry, just busy trying to keep my car running this past few days.

No problem; you already said it would be after Spring Nats before it could be checked, so that wasn’t intended towards you :)

Working out the final details for my application and should be pulling the trigger soon. Just some added details; the 2-way non-remote shock comes standard with dual-digressive valving pistons and standard rebuild service is $240./shock including all seals etc and service. You pretty much have to send them to MCS for rebuilding and modifications, or rather through their distributor network.

will you be using unmodified oem rear top hat?

I have 5/8” spherical bearing cups welded into the top of the steel RX8 shock hats. It raises both the pivot point and body end position slightly over where the OE shock is. I would not recommend using high end racing shocks with an OE type rubber shock bushing configuration. They side load the shaft & shaft seal too much. So this set will be slightly custom for my fitment, both in the size of the top pin connection through the top bearing, but also in the spacers on the bottom mount. Or at least I think it will be. The shock will also be longer in body and droop lengths than my current Koni shocks. Still waiting to hear back on that though. As it was originally proposed, they were about 9mm shorter, which is maybe ok in the NC MX5, but too short for the full height RX8 shock hat imo.

I suppose it’s not clear to me if they’ll do something different as a standard configuration or if there will be such a thing. You might be able to get a smaller pin connection and use the screw in type spherical mount like on the Ohlins maybe. I don’t really follow those parts and am not sure what sizes are being used. I’m just pioneering this through to work with some of the configuration I already have. The final cost isn’t 100% yet, only because the 18mm spherical lower shock mount piece with the DA adjuster is in production for the first time and not quite finalized yet. I don’t expect it to be a big cost difference though, just unknown at the moment.


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do you have pictures of your rear top hat setup with the spherical bearing.

Any word back from MCS? I'm a dealer for them and starting my track rx8 project soon, but haven't really talked to Wyatt about them yet in detail. Following along here anyway.

I bought a set and am working through it with them now. Only issue is they presently only offer a protruding gas fill bolt that has an interference issue up inside the OE rear shock hat. The ideal solution is a countersunk fill bolt if we can pull it off. Otherwise the shock hat top has to be modified, which is not that big of a deal for a fabricator, but not as simple as just cutting the top bushing cup off having some bearing cups welded on. It’s happening on my car one way or the other though. :)

It really comes down to what shock connection you have. For the standard 10mm OE size shaft you can get the 2-pc screw-on monoball/uniball/spherical bearing adapter from Sakebomb Garage. I suspect it may have a 1/2” ID bearing though. You would need to talk to them to verify this, but if true then you could use it up to the 1/2” shaft size with the proper heim adapters.

However, a lot of higher end race shocks use a 14mm shaft or stud connection size there. Then it’s more typical to use a 5/8” bearing and adapters. Which the larger the bearing the higher it’s load capacity. The rear inverted shock setup is carrying the actual spring loading, not just the damping force load. It’s a bit more work to fit the larger bearing such that the bearing is easily serviced.

I’m researching and working on a threaded or bolt-on adapter solution for using the larger bearing there. It would eliminate the need for welding, but will require at a minimum cutting the dished bushing cup off the top and also a larger opening. It’s fairly do-able and there’s some similar solutions out there for other applications, but they aren’t exactly what we need. If it pans out I might have a run made and offer them up for others. Not really trying to make money, running off a few just brings the cost down a reasonable level. Or if I find something that readily works and is available I’ll post it up for everyone else to know.

So the gas bolt solution is likely going to be custom cap-ends on the rear shocks. Waiting to hear back confirmation on this. But this isn’t going to be the lowest cost option. I’d guess maybe $4k for just the shocks with perch & mount hardware (no springs or mounts), but won’t know for sure until this is finalized.

What you do get is a true rear coilover setup that’s not side loading the rear springs or binding the shaft motion with easy dual adjust access at the bottom of the shock.

how big is the gas bolt, and can you just drill a hole on the hat to allow clearance for the bolt when the shock move side to side. you can use a rubber cap to cover up the hole or weld a steel cap.

I don’t care for Russian roulette, but be my guest ...

Well it looks like Plan B is required; modifying the shock tops instead.

The shock top itself is easy, the upper chassis support bracket mount will require some finesse, but not really that big of a deal fabrication wise.

I am getting quote on mcs
Eventhought they are in middle of moving shop, they said they can still build the set in week

I am thinking I am pretty max out on my current spring shock set up (mint condion mazdaspeed shock and spring)

Update, just place my order , wonder how many sec I can improve by suspension alone

My mcs had been made
Will test it at dec's track day
Wonder this set up will be improve 1.5 sec@😀

Rear spring package looks very long.