Miata Turbo Forum - Boost cars, acquire cats. - My turbo specs

Quote:

Originally Posted by evank (Post 379352)

I base most of my turbo opinions from my education at the School of Paul.

LOL, but we haven't gotten to the chapter about "safety" yet, except for urgent stuff like AFR. :)

Paul's manifold is a "if you have to ask the price you can't afford it" so I don't know that its a reasonable standard. If it had a real price, I and a few others might run it with the promise of some longevity.

Quote:

Originally Posted by Project84 (Post 379343)

Hustler, 1 bar as in 15psi? And, I don't know what turbo you have, so if you could provide that info I could get the full picture.

I realize the quality of the BEGi parts is higher than my ebay parts, no doubt there, at least if the old saying "You get what you pay for" holds true.

I'm not sure if this person is wanting to trade a BEGi DP or just a custom one, that part wasn't made clear.

I guess the real question here is, being I'm wanting to stay on a tight budget w/ this car (for now anyway) and have no plans of rebuilding or upgrading the bottom end, which turbo would suit me better? My T3/T4 .63 A/R w/ OBX manifold, or a gt2560r w/ Begi mani? I wasn't really considering the trade at first because I just want to drive the car and not mess w/ anything I don't need to, but if this is widely suggested, maybe I'll spring for it.

EDIT: This is tough! Seems like some people don't mind lag, particularly those who live with it, and some people hate it; those who don't have to deal with it.

What is safer for the 175k mile bottom end? To roll into the boost, as with a smaller turbo? Or is it more of a boost is boost, it doesn't matter, kind of situation?

Lag and "positive MAP threshold" or spool are 2-different things and you need to learn to differentiate them. I have a gt2860rs with a .86AR turbine. My turbo makes target boost at 4000rpm and that's fine, even on the auto-x. I'd love for it to spool sooner, but that's not going to happen. That big turbine housing and the horsepower friendly turbine allowed for some awesome spark table #'s that I haven't seen replicated on this site which gave much more torque than most see...substantially more. People wig-out about it making target boost at 4k rpm...but that's slightly more than half of the effective rpm range of the car. Pretty hard to argue with that.

Lag is how long it takes to make the turbo spin up to target speed to make boost, once in the "positive map threshold" in the rpm range. This is a bit of a problem on my car right now, and Steph from BEGi commented emphatically that something was weird on mine to make it build boost so slow. I need to check the exhaust gasket that I "fixed" with a dremel...

With all that said, I wouldn't change anything on my car. I got exactly what I wanted, which is exactly what Corky recommended.

I had a t3/t04e on my 482whp/488wtq corrado, but I probably had a different compressor wheel and turbine. You could probably shrink-down the turbine housing and get away with using it on the recommendation of someone who knows more about this shit than I do.