Our New 2012 PRHT SS Project....

Miata Parts, Intakes, Superchargers, Headers, Exhausts, Shocks, Springs, Sway Bars, Brake Kits, Autocross and track mods.
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

That chart compares totally stock.....and after install of complete exhaust setup (RoadsterSport Street Header, RoadsterSport Midpipe and RoadsterSport Q exhaust).
Brian Goodwin
Good-Win Racing
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jkjcorp
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Re: Our New 2012 PRHT SS Project....

Post by jkjcorp »

Under Guard (1x needed, Mazda Part # n121-56-1e0c)

Under Guard bolts (5x needed, Mazda part # 9946-30-616). These screw into existing holes that already have nuts welded on opposite sides of the OEM braces. If you changed out the OEM steel brace for one from IL Motorsports or Beatrush, then you will have to get 3 nuts to hold the screws that go on the new braces. IL Motorsports supplies the nuts and also the long, thin plate that holds the little flap on the Under Guard. Check their PDF instruction manual NC0-0963 for complete info.

Transmission Cover (1x needed, Mazda part# ne85-56-1a0b)

Transmission Cover screws (2x needed, Mazda part #9946-30-612). Like the Under Guard, these also screw into existing holes with nuts already on them. But if you changed out both the OEM front- and X-braces, then you will have to supply 2 nuts. Again, the IL Motorsport braces come with the nuts, but not the screws. These are the same sized screws as the one for the Under Guard, except a little tiny bit longer. You can forgo ordering two different screws and just go with one as I didn’t see any difference when I installed them. These screws are metric sizes you can get from the hardware stores, except they have extra wide washer-style heads so you don’t have to use a washer. Probably available from Mazda USA.

Transmission Cover flange cap nuts (2x needed, Mazda part# B100-68-615). These are plastic nuts that go into existing bolts sticking out from the car. There are some already holding other parts under the car, so I think Mazda USA probably has them.

I got all the parts from MX5Parts.co.uk for about $300 delivered, with the BP exchange rate currently at $1.5, which is extremely good. The parts they sent me came from Wolverhampton Mazda in England. You might be able to get it from them directly but their shipping might cost more.
Ranfy
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Re: Our New 2012 PRHT SS Project....

Post by Ranfy »

Brian, I have a 2007 PRHT GT with the Bilstein sport suspension package. I had a Mini Cooper which had flat, no body roll, cornering but a very harsh ride. I don't like the amount of body roll on my MX5, but don't want a harsh ride on my daily commute. What do you recommend?
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

Ranfy wrote:Brian, I have a 2007 PRHT GT with the Bilstein sport suspension package. I had a Mini Cooper which had flat, no body roll, cornering but a very harsh ride. I don't like the amount of body roll on my MX5, but don't want a harsh ride on my daily commute. What do you recommend?
The 2007 sits HIGH....my suggestion is start with just the Progress springs. That alone will make a big difference because it will fix the center of gravity and give you enough spring rate to reduce squat, dive, and quite a bit of the roll in the turns. If after the springs you want more, then let's talk about HOW MUCH more you want. If just a little then I would say our Racing Beat sways. And if you want a lot more reduction in body roll after the springs then I would say add the Progress Sways. My wife's car rides great with both, yet is very flat....but our roads are good here in San Diego and every choice is a compromise and might as well take it just one step at a time.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
projectrally
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Re: Our New 2012 PRHT SS Project....

Post by projectrally »

Brian,

Earlier on in this thread, you mentioned working on an Air Dam for the NC2. Any progress on that front?
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

projectrally wrote:Brian,

Earlier on in this thread, you mentioned working on an Air Dam for the NC2. Any progress on that front?
Sorry, that idea not forgotten but has not gone far yet. I still hope to get it done this Fall.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
JamesD840
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Re: Our New 2012 PRHT SS Project....

Post by JamesD840 »

Brian wrote:
Ranfy wrote:Brian, I have a 2007 PRHT GT with the Bilstein sport suspension package. I had a Mini Cooper which had flat, no body roll, cornering but a very harsh ride. I don't like the amount of body roll on my MX5, but don't want a harsh ride on my daily commute. What do you recommend?
The 2007 sits HIGH....my suggestion is start with just the Progress springs. That alone will make a big difference because it will fix the center of gravity and give you enough spring rate to reduce squat, dive, and quite a bit of the roll in the turns. If after the springs you want more, then let's talk about HOW MUCH more you want. If just a little then I would say our Racing Beat sways. And if you want a lot more reduction in body roll after the springs then I would say add the Progress Sways. My wife's car rides great with both, yet is very flat....but our roads are good here in San Diego and every choice is a compromise and might as well take it just one step at a time.
Brian,

What combo of springs/sways/shocks would you recommend to reduce body roll, improve handling, & yet keep ride quality high? Would you stick to the same plan for an '08 PRHT GT without the factory Bilstein sport suspension package or take it in a different direction? Interested on hearing your thoughts on the Eibach PRHT springs versus Progress springs also - would the Eibach's higher spring rate be an unacceptable compromise to ride quality?
Chuck H
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Re: Our New 2012 PRHT SS Project....

Post by Chuck H »

JamesD840 wrote:
Brian wrote:
Ranfy wrote:Brian, I have a 2007 PRHT GT with the Bilstein sport suspension package. I had a Mini Cooper which had flat, no body roll, cornering but a very harsh ride. I don't like the amount of body roll on my MX5, but don't want a harsh ride on my daily commute. What do you recommend?
The 2007 sits HIGH....my suggestion is start with just the Progress springs. That alone will make a big difference because it will fix the center of gravity and give you enough spring rate to reduce squat, dive, and quite a bit of the roll in the turns. If after the springs you want more, then let's talk about HOW MUCH more you want. If just a little then I would say our Racing Beat sways. And if you want a lot more reduction in body roll after the springs then I would say add the Progress Sways. My wife's car rides great with both, yet is very flat....but our roads are good here in San Diego and every choice is a compromise and might as well take it just one step at a time.
Brian,

What combo of springs/sways/shocks would you recommend to reduce body roll, improve handling, & yet keep ride quality high? Would you stick to the same plan for an '08 PRHT GT without the factory Bilstein sport suspension package or take it in a different direction? Interested on hearing your thoughts on the Eibach PRHT springs versus Progress springs also - would the Eibach's higher spring rate be an unacceptable compromise to ride quality?
Not Brian, but figured I'd toss in my 2 cents. First, Eibach springs aren't higher rate than the Progress. They're lower rate with more drop, so they're actually going to ride worse than the Progress springs. If you're on a super-tight budget, I'd think that your best bet would be Progress springs with a set of low-mileage NC2 OEM Bilstein shocks that somene took off their car when upgrading, plus a swaybar upgrade. Pretty much any swaybars are better than stock. RX8 bars are the cheapest, but adjustables ones like Racing Beat are still pretty reasonably priced.
2019 Arctic White RF GT-S
SmartTop, coilovers
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

Indeed the listed rate on the Eibach is higher than Progress but our simple tests here suggest the Progress is higher rate and with less drop it will have better ride than the Eibach....primarily because there is more travel with the Progress springs BEFORE we hit the bumpstops.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
JerryM396
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Location: Coastal North Carolina

Re: Our New 2012 PRHT SS Project....

Post by JerryM396 »

I had the Progress springs and Tokico HP shocks installed on my 2007 PRHT per Brain's recommendation and am totally satisfied with the results. Resulted in about a 1" drop and the ride has been fine with us on several multi-week trips. Still too much lean but for my purposes I can live with it.
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