Hi, folks ... my name is Jon. My 92 Miata has been offered up to the testing of things that are not supposed to work reliably. I am here to share whatever knowledge i can.

 

I'm not sure what you are up to, but welcome.

 

Ok

 

Wut?

 

Thanks for the welcome, What have i been up to? I acquired a 92 miata with 192K on the clock..... My wife purchased it for my b-day (twas intended to be a joke,.. like a haha,... here honey,.. drive this turd hahaha,... kind of joke). Then, I go to the web to find some sort of glory in my gift and boom.....MiataTurbo, ClubRoadster..ect......Apparently, there is a following for this cheap, upgradeable, track thrashed car. I remember driving one in my youth and quickly recalled the lack of forward momentum provided in stock form. So,..I read of great wonders of turbo enhancements. Tho, I am more familiar with bottle feed engineering. I have been working out a turbo setup, I did spray the original engine,....to much delight until failure. Then, I acquired a used engine, a wobbly *** short snout for a gift of nothing. I rebuilt the engine then installed the CX racing turbo kit,.( go ahead and giggle)., just to see how long it would actually last, And, the fact that ebay kits are mostly frowned upon on this site, and others. I thought why the hell not... lets just see. So.... with some many alterations my setup is a intercooled T28 at 14psi ,440 injectors at 28 psi with 1:1 reg, at 9 degress static timing, altered the afm, with stock ecu and internals. I've been letting the ecu set long term fuel trims as i incrementally raise the boost and fuel pressure. The stock ecu has not the ability to compensate for any more. I have no idea of my output numbers.

 

Wait, how are you using 440 injectors with a stock ecu? You don't have a fuel card or one of those begi regulators or anything, right?

 

He did say he was at 28psi fuel rail pressure, I believe. The sentence structure and phrasing was a little difficult to follow.

MBTech, is English your second language, perchance? You have an interesting setup with the stock ECU. I don't know of others doing it the way you have. You would probably pick up many horsepower by switching to a programmable ECU.

 

I am currently running 28 psi on the fuel rail at 14 psi boost . I started at 23 psi on fuel and 8 psi boost. I incrementally increased both as the ecu set long term fuel trims altering the afm a few clicks as needed along the way. I agree that a piggyback or a aftermarket ecu is the best way, but that is missing the point of my testing that is based on what can actually work without all the electronic platforms that are mainstreamed as the solution to boosting a stock miata. Yes, English is my language of choice, Though,.... I do apologize for my substandard form of typing and grammar. I tend to type as if i am talking rather than reading. I am mostly here to share any data I can for those who are attempting to boost on a budget or wanting to avoid going the piggyback or ecu upgrade route. My tactics for tuning are not the best by any measure. They are crude,simple, but effective. It does take time.

 

Well it sounds like you made it work, so that's cool. How many miles on it so far?

 

I would worry that lower fuel pressure would result in poor atomization of the fuel.

 

I installed the engine and turbo kit about a year ago.I was also concerned that the injectors wouldn't produce well at low pressures, but ,when I tested my injectors at 20, 30, and 40,psi. there was no noticeable difference in spray pattern only the increase in collected volume.

 

Good to know.