roadster sport11

Miata Parts, Intakes, Superchargers, Headers, Exhausts, Shocks, Springs, Sway Bars, Brake Kits, Autocross and track mods.
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ronc
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Joined: Fri Jun 11, 2010 6:10 am

roadster sport11

Post by ronc »

hey brian; i am seriously considering the roadster sport11 for my 07. i see that its adds about 8 horsepower, is that at the wheels? this would be the only performance mod to the car other than the dynotronics tune i am also considering. if i could get 18-20 horsepower at the wheels between the two i will do it.what do you think? thanks ron
Brian
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Re: roadster sport11

Post by Brian »

The big gains are found with a header....but click on the exhaust blog from the listings in the website of that exhaust to see the dyno details and discussion.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
ronc
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Joined: Fri Jun 11, 2010 6:10 am

Re: roadster sport11

Post by ronc »

i am not interested in any other part of the exhaust system. your site says a gain of 8 hp for the roadstersport duals; can i expect a figure somewhat near the eight at the wheels. you make and sell the product you should know. thanks again
Brian
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Re: roadster sport11

Post by Brian »

Yes, as much as 8 hp at the wheels on 06+.

But the point I was trying to help you discover was that ANY of our highflow exhausts give you gains, which leaves you making a choice based on SOUND preference. And answering the SOUND preference question depends on variables such as, but not limited to, whether a header change might be in your future. Very common that folks start with Roadstersport II, appreciate the gains enough to want MORE, and then add the header.....at which point the Roadstersport II suddenly becomes too loud, and then they buy a Roadstersport Q. Thus, I usually help folks find the sound file blog and dyno charts so they can plan ahead and think about where they want to end up.

Assuming no header in the plans then the RoadsterSport II is a fine choice for manual transmission MX5. However, as also explained in those blog and forum dyno discussions, even if no other exhaust mods are planned we prefer the Q on automatics and any MX5 with the PRHT.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
ronc
Posts: 23
Joined: Fri Jun 11, 2010 6:10 am

Re: roadster sport11

Post by ronc »

thanks brian and i do appreciate your insight on all the variables that come with your different mufflers. its nice to talk to a vendor that knows and understands his product. the roadstersport duals sound just about right for my taste from all the clips i heard. i just wanted to hear from a pro like yourself that the 8hp is attainable and not just some marketing gimmick. you will be getting my order very soon and with the dp tune my 20hp gain will be very real.(dynotronics claim 10-14hp but i will be happy with 10,11 or 12). again thanks for an honest answer and looking foward to doing business with you in the very near future.(but i have bought from you in the past) btw i did read the blogs and graphs but i gets to complicated for me, i'd rather just get a flat out answer from someone who has extensive knowledge with the product, YOU! thanks for all your help. RON
Brian
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Re: roadster sport11

Post by Brian »

Your mileage may vary...and I suggest that your focus on the end number misses the nuance in the data and the dozens of variables that may lead to a wide range of results. See, for example, customer dyno results posted on page 6 of the dyno thread wherein he got 11.8 at the wheels from just our RoadsterSport Race and a K&N Drop in....but our results from just a K&N panel drop in were consistently zero to negative (which suggests he was getting more from the exhaust than we have ever got here, or?). Each car is different, lots of variation in dynos, some motors assembled better than others, Mazda has about two dozen different ECU calibrations and some respond better than others (some add the header and get perfect air fuel ratios without a reflash and others are too rich and need a reflash to optimize the results), and on and on. Thus, if your expectation is that every NC will get the same precise result that we got, or that any one customer got...then that expectation is NOT realistic and I can burst that bubble now and guarantee you will not get the same gains on every NC. That's a conclusion that you would find in that long dyno thread over and over....as I wrote in that dyno thread back in 2007:

"That dyno above is on our 2007...which is not stock. For reference, our 2007 started out stronger than our 2006 by nearly 10 horsepower (141 for the 2007 stock versus 132 at the wheels stock for our 2006 peak) on the same dyno. Why? Don't know. Perhaps our 2006 was just too new and tight when we did the baseline, perhaps Mazda has changed the flash program they are putting in the ECU now and the fueling is now a little tighter than the pig rich we saw in the 2006, or perhaps even a little more spark advance; or perhaps our 2007 motor is just screwed together better, don't know. On a separate but related note I will add that we are consistently seeing weaker results with mods to the Automatic transmission NCs. Why? Don't know but it is reasonable to theorize that they have a more conservative state of tune...perhaps a more conservative timing curve or fuel curve. Either way, I understand that for 08 Mazda is going to re-rate the auto equipped cars down a few HP from the manual transmissions and I suspect this is merely acknowledging the more conservative tune that our results have been evidencing. I don't think this means tuning an automatic is a waste of time...but our experience so far suggests that those with the auto trans may expect small gains...at least until such time as we have ECU control over timing and fuel."

The funny thing about my 2007 is that motor did turn out to be a REALLY STRONG example. Further in the thread we get to when the Cosworth supercharger gets added and we turn about 260 hp at the wheels....or about 50 more than anybody at Cosworth expected or even hoped to see. We were so alarmed by the results that we ran across town to another dyno the next day and repeated the tests....and still hit way over 260. To this day I have never seen a Cosworth powered NC on stock boost level repeat that result. My 2007 later got a hot Cosworth built motor (using stock crank) and it could not repeat that strong showing on stock boost with same ECU calibration, same dynos, etc.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
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