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 »

I did eventually put in a MotoEast tune, though I need to give Mike some more datalogs to finish up that process and get it back to the dyno. Main reason for doing the reflash on this car was to get rid of the 2nd gear torque limitation that the factory included on 6speed cars, makes the car quite a bit more fun around town to have that limitation gone.
Brian Goodwin
Good-Win Racing
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Bart
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Re: Our New 2012 PRHT SS Project....

Post by Bart »

Brian,

It’s been over 1000 miles and yesterday, once again since my last few attempts, I got under the car and loosened the bolts on the lower part of the shock and upper suspension arms and drove over 10 miles trying to get the car to settle to less than 14.5 inches. The front, with the Progress sways and spring installed, has settled to 13.5. But, after all the driving and bouncing on the back of the car and torquing the bolts on the ground it remains the dreaded 14.5 inches. I’m about to give up, but an idea has occurred. The diagrams that show the exploded view of the rear suspension and the wording on the same talk about the need for the bouncing and torquing while on the ground. So it appears that Mazda knows about this problem. So, if I take it to my local Mazda shop would they be able to make it sit lower?

PS. My car is the 2010 Touring with soft top and sport suspension upgrade.

Thanks
Bart
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

Yes, stuck bushings. See it with every brand of springs and coilovers on NC MX5....because it has nothing to do with the springs or coilovers, it's stuck bushings. Yes, Mazda knows all about it, we know all about it too, that's why we included the Mazda TSB on the subject in the product description for the Progress Springs in the hope folks will read the product description and follow our tips there.

Note that in addition to the bouncing on the ground, Rocky (head mechanic here) will sometimes need to use a flat head screw driver to peel the bushing edges away from the suspension arm/link to which they are stuck. Rocky will also jack the entire car up by the spindle at each corner to get those bushings unstuck and moving. The result here is that we get the same lowered front and rear every time with these springs, week after week, month after month.... but there is no secret to getting it done, and it's not about going through the motions or using any one particular trick, results will not change until you get those bushings to release and move.

Another thread at Miata.net on the same topic today AT THIS LINK, and I notice at least one customer therein mentions same method of jacking entire car by the spindle.
Brian Goodwin
Good-Win Racing
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Bart
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Re: Our New 2012 PRHT SS Project....

Post by Bart »

Brian,

Thanks for the quick reply. This gives me encouragement. I'll give it a try.

Question: What is the spindle?

Thanks
Bart
elloco54
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Re: Our New 2012 PRHT SS Project....

Post by elloco54 »

Brian
Would that same issue cause a problem setting the camber on the front suspension. Took my car to have the negitive camber increased and the most they could get on the pass side was 1.3 deg but the dr side would get over 2 and I have H&R lower springs and the ride height is good.
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

Sorry, if heights are the same (and caster and toe the same) then not clear to me why they are having issue getting more even numbers on that camber.
Brian Goodwin
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Bart
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Re: Our New 2012 PRHT SS Project....

Post by Bart »

Update:

Well, half a loaf is better than no loaf at all. After all is said and done, I achieve 14 inches in the rear. The front is still 13.5. I wanted that number for the rear, but I'll settle for the 14 inches. Apparently the silicon spray on the bushings and anti-seize on the cleaned bolts helped.

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

Post by Brian »

Good work, that is where my wife's car was after install and it settled further to 13.8 with time at the rear.

The guys getting 13.5 rear are usually using the KONI SPORT shocks with those springs, which are lower pressure than what you have in there. Notice the title of the thread I linked you to at Miata.net a few posts above, it is all about use of these springs with the KONI shocks.
Brian Goodwin
Good-Win Racing
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JohnB082
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Re: Our New 2012 PRHT SS Project....

Post by JohnB082 »

Brian,

I just got a dyno on my stock 20111 GT PRHT (141.65 HP 130.7 TQ on a DynoJet, SAE corrected) for my baseline. I have your ceramic coated street (catted) header, mid pipe, and Super Q yet to be installed and will get the a dyno after the install. I plan on getting a tune at that point and another dyno. Exhaust-wise, my car looks like your 2012 PRHT SS Project car, albeit a year older, and I am curious as to what your dyno results are for that car after the tune.

John B
"...remember, no matter where you go, there you are."
Buckaroo Banzai
Brian
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Re: Our New 2012 PRHT SS Project....

Post by Brian »

All the gains are the bolt on changes, tune didn't get us any additional gains on this project. Some cars adapt to the header change better than others and apparently this one adapted perfectly because adding the tune didn't get us any more. Tune still helped in that it removed the 2nd gear torque limitation that Mazda included in 2nd gear on the 6speed cars. But we should do some more work with Mike at MotoEast on it, been busy and have not had a chance to give a second effort to getting gains with the tune on this one.
Brian Goodwin
Good-Win Racing
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