My 8 is stock and I'm considering what upgrade to do next.

I find that my 08 doesn't corner like my 05 did, so that's where I am thinking I want to focus my energies.

My gut says to go with the MazdaSpeed strut tower bars and better tires (the ones on there now are crap).

Thoughts?

Beyond that, I was thinking about changing the intake, but only if it's worth it. My butt dyno says my 05 with the MS intake had a little more oomph. I'm considering the AEM CAI or the RB Revi. Are either of these truly worth it?

Later on, I will probably swap out my clutch and flywheel...

 

https://www.rx8club.com/rx-8-discuss...rx-8-a-233937/
This will help you in deciding in which direction you want to go with the intake or any other power related mod, alot of helpful info in there.
I personally would go with coilovers, made a huge difference for me!

 

I know you aren't a newbie, but your question about the intakes is pretty basic. Might want to poke through this thread for some ideas of where you want to go: https://www.rx8club.com/rx-8-discuss...rx-8-a-233937/

 

Thanks... I'll read through the thread.

 

I read through that thread.

Anyone have thoughts or recommendations on strut tower bars?

Are there any that are notably better than the MazdaSpeed ones?

 

Those aren't mentioned in the thread. I'll add that. If you don't mind, I'll close this and you can ask there?

 

strut bars arent going to give you the handling that youre missing

 

Correct, strut bars counteract the flex distance between the tops of the paired front or rear shock towers. So if your chassis is flexing, then you can see an improvement. If it's not, you won't.

 

Yes... just trying to find the best ones in terms of value for money!

 

IMO, a 2-point strut bar is a 2-point strut bar. I have the 6-pt GTSPEC version ( GTSPEC 6 Point Front Strut Bar ) and consider it to be an noticable improvement. Mazda seems to agree - they went to a 6 (or 4 -can't remember right now) point bar in the Series II.

In any case, it's a secondary effect. Tires, sways, and springs/shocks or coilovers will give you bigger effects.

 

I have trouble advocating the multipoint strut bars that don't attach to structural parts of the chassis. The firewall just isn't strong enough for me to think that an anchor there is viable. The only way I could see a stiffening improvement there is simply because the shape of the bar itself resists flex more than a 2-point bar. And the other attachment points just hold it's orientation/place.

 

when you say it doesnt corner as well what do you mean exactly?
take that issue and work on it specifically
ex: if it's body roll buy a sway

I have the MS strut bar...personally I can't tell a difference...oh and your engine cover wont fit

 

Unless your car sees the track often and has a stiff track setup suspension, you'll likely never really notice a difference in upgraded strut bars. You'll likely feel a placebo effect though. The master cylinder brace the MS bar offers is noticeable on the street if your really lay into the brakes. Our chasis is already stiff and it takes a lot to flex it, unless your suspension is very stiff, your tires are super sticky and you're putting high G loads on the car (ie 100mph turns on a track), I doubt your feel any chassis flex. If anything, stiffer or mulit-point strut bars will just make highway and street driving more annoying.


They look pretty though.

 

"4 point" on the S2, and i put that in quotes because as Pearl said, I dont know exactly how much benefit the attachment to the firewall is. It does form sort of a truss style brace which may be a bit stronger than the S1 bar, but honestly the bolt points on the firewall are weak if anything. I couldn't imagine that it has remotely the "performance" or whatever you want to call it of a bar that has a brace across the entire firewall like the GTSPEC.

 

I can see the GTSPEC bar strengthening the firewall itself by it (some at least), except the side anchor points aren't really heavy duty either, since it's still part of the crumple zone.

Chassis underbracing has to be the most beneficial, and even then we already have that. It's shocking how much bracing will help other cars, my Miata for example (convertible of course is more flexible), but the 8? Not really all that much.


I think the handling difference is largely the tires first...

 

I had a 4 point system on my RX7. While the main bar helped that car a lot, I did feel a difference when I added the two bars that attached from the towers to the firewall. But, that car had a completely different suspension setup than the RX8.

 

^ I assume that was more of an "H" bar design than the "triangle" design of the S2 one right?

 

Mine no, it was more of a triangle (trapezoid).

 

The best example I can give is that I love taking those curvy freeway entrance/exit ramps at high speeds. In my old Shinka, I could take them at 55mph easy. In my 08, it's more like 45mph before I'm sliding off the side my seat...

 

So...butt grip?


And that isn't much of a description if it's car grip


When you are going through the curve, do you feel the front end plowing? The rear trying to come loose? just general loss of grip?

 

The firewall mounting points are there mostly to keep the brace from moving vertically, the fender ones for side-to-side. As long as the bar across the back cannot move, then the bar across the front cannot move either since the tapezoid is essentially a triangle. I also have the matching lower brace, and attribute about 1/3 of the improvement to that, 2/3 to the upper. Review here: https://www.rx8club.com/wheels-tires...4/#post3536450

If you really want to go whole-hog, they have a brace for those 'weak' fender attach locations: GTSPEC Fender Reinforcement Brace - Mazda RX8 (2003~2008) | www.gtspec.com

But now you're up to ~$900 in braces. D-specs + springs will give you a much bigger difference for the same money, as will a $350 set of sways. The only reason IMO for going from a stock 2-pt brace to another 2-pt brace is to get one that also braces the brake master cylinder (which may/may not be needed). Or for hood candy if you're into that.

Experimenting with rear braces (GTSPEC lowers and small strut brace inside the trunk) yielded little noticable gain on the street, though my rear strut towers are already sortof braced with the spare tire carrier.

BTW, the best brace for a Miata would likely be welding a roof on it ...

 

Well, it's both. The car just seems to not be as planted as my old Shinka.

The only differences between my 05 and 08 are:
- Better tires on the shinka
- MS strut bars on the shinka
- Tokico shocks on the shinka, bilsteins on my 08

However, I had the same tires on my 05 and still felt that it cornered better...

 

I would suggest a alignment.

 

+1 ^^^

and some stickier pants.

 

Needs to be measured with a sphincter tensiometer?

Really though, there should be little difference between the two cars. Assuming no blown out shocks, and good alignment: the 08's tires suck!