Great review! Was that in MPH or KPH? I really only need tires which would offer a combination of good dry/wet traction, turn-in, life. I'm sure that there are more than a few choices on the market with such attributes.

Thanks, and it was in MPH.

I would really recommend the Michelin Pilot Super Sports if you are not tracking nor autoxing. I think you could get an easy 20k+ out of the tires and Michelin provides a 30k warranty for the tires. I thought they were really great on the street in dry and wet (I live in Seattle), I just hated them on the track.

Another tire that was brought up earlier, which will be a lot cheaper are the Dunlop Direzza Z1 Star Specs. I do not have any experience with these tires, but a lot of the 8rs up in the NW where it rains a lot use this tire for autoxing. They claim it has excellent dry and wet grip. The only reason I haven't tried that tire is because I hear it doesn't hold up well on the track. I think the Dunlops will save you a good $300 over the Michelins, I just don't know how long they will last.

Good luck finding a tire. There are so many different tires, and it is a lot of money to find out if you are happy with your choice :)

The camera's depth of field distorts the perception of speed, a lot.

I have used Dunlops before, their DZ101, and did enjoy them.

I appreciate the feedback.

By the way, if anybody is looking for a good deal on Enkei wheels don't hesitate to contact me!

Slight update for those interested; I just installed the Fat Cat Motorsports shorter (than stock) / stiffer bump stops and can tell you that the car has a lot more grip. It turns out the replaced bumpstops were cut too short causing too much lean / weight transfer in hard corners and possibly change in suspension geometry as the RX8 / Miata are designed to corner on bumpstops. These new stops are amazing and a very worthwhile mod for all lowered 8s. There's definitely more grip now as they effectively increase the spring rate at the limit.

WTF.....are you thinking.....it is NEVER a good thing to be hitting the bump stops. They are there as a last ditch only. Instantaneous increase in spring rate at the limit equals very bad loss of traction and often a crash :(

I could be wrong, but isn't the Rx8 designed to corner on the bumpstops?

No car is designed to corner on the bumpstops....

Fat Cat Motorsports - Tokico products - Miata 06+, RX-8 04+

I doubt that they'd use false information to promote their brand. regardless, the stops I removed were 1/3 of the length of the "shorter" fat cat stops. Can't be good. Im not trying to argue with you, FYI, just trying to get the facts right. Also, the shock rod is only about 6" long full extended, at least the fronts. There can't be much left of it once the car is on the ground

I hate speedbumps...lol

I call BS on that site.

If you lower a car, there is less distance available until you "bottom out". That is likely why the call for shaving the bumpstop. It gives you back some of your suspension travel. Now the only question is if your shock becomes the new bump stop.

Which is why Moton's don't have them...And is why I am on Moton's!

Bump stops are there so that if a severe event causes compression it will not result in the shock bottoming out full metal on metal.....

Hitting the bumpstop is slightly better than that :)

If you are hitting your bumpstops all the time you have a problem with damping, springrate and likely with the design of the shock itself

The wording of that page is poor...and the premise is poor.....but having "tuned" bumpstops is better than hitting bottom

Food for thought, fellas;


The graphs in that video are of dyno'd OE RX8 and NC (same) bump stops. You get a rising spring rate on front bump stops. Simply cutting them would make this worse as now you've also increased the spring rate by having less of the softer initial rate and more material that's thicker (so spring rate and initial nose force are higher). If you combine this with a lowered car where the springs usually DON'T cause the car to oversteer you'll have stiffer front bump stops, stiffer front springs vs. rear springs and a car that WILL need a bigger rear bar or ridiculous driving antics to want to rotate. Very annoying situation, but very safe for makers of aftermarket springs. Granted, the car would probably not spend a lot of time on the stops, but they're not just there to prevent the shock from bottoming out only but to also play a role in the spring rates as can be seen in the dyno graph.

This might be an extreme picture but the physics of the suspension are against you by trying to kludge the factory stops. It would depend upon how else the setup is tuned, but my point about cutting OE bump stops is that they aren't designed to be linear because that would induce too much oversteer - the last thing lawyers for the OE want to see. So you would introduce even more non-linearities with random slicing. OEs are generally more worried about someone getting loose and nutty on the street, esp. in a car with great suspension design like the NC/RX8 have (and the power of the RX8 to get you loose faster than an NC). The NC has a 22mm front bar, the RX8 is 25mm or 27mm for Sport, I wonder if they chose those stiffer sizes for a reason.

The cars are quite different in weight and roll center.....so they need different bars

I watched the video...and they are talking about the rate in the bumpstop...not the spring

This still doesn't mean that you should be on the damn things in the first place.....

Stiffer sways will help keep the bumpstops out of play in hard cornering. These are on my car now and I really like them:

Progress Technologies MX5 FRONT and REAR AntiSway Bar Combo! for MX5 2006-2013

Yes, Miata bars. A modest but significant increase in rates together with being adjustable at both front and rear.

Good stuff. Would you know what the stock rear bar diameter is?

The simple truth is that most RX-8s ARE cornering on the bumpstops. Especially if you've lowered the car and run OEM length shock bodies with mild spring rates. In this configuration (which the OP has) trimming the stops too much will result in an abrupt change in roll rate once the stops engage with a resultant loss in grip at whatever end of the car hits the stops first.

Finessing bump stops can and will improve handling, and the FatCat stops are a well thought out product. To the OP, you chose well and it's good to hear you've solved the problems. Now put some good summer tires on and be prepared to be amazed.

Thanks for the input :)