Mech5700

The background: 10AE, 153k miles, was supercharged at one point in its life, was used primarily for autox before I bought it, I track it a few times year + it's my DD, and has ~210 psi in each cylinder. I've had it for almost 10k miles. It runs strong, sounds great, and the engine has never given me any mechanical problems, so now I'm looking to boost it.

I have a MS3x coming this thursday. Will obviously lrn2tune before I attempt to run a turbo. duh.

I am looking at a EFR6258 setup with ARTech all the way back, ID1000's, yada yada yada, you know which setup I'm talking about...

Am I thinking crazy? I know this little engine can handle a decent amount of power, but is this too much? I'm not looking for 300+, I'm talking 2-250 max whp here. I read threads of people putting holes in their block with this thing, but what was the real cause? Bad tune? Detonation? Too much boost?

Will this turbo be ok at the lower HP levels I'm looking to go for? Or should I be looking at a different turbo?

For specs: BorgWarner EFR 6258 Turbo - Full-Race.com

Just some clarification is what I'm looking for, any input will help.

Thanks dudes.

Mech5700

For more specs on the car: https://www.miataturbo.net/meet-gree...sh-meat-77383/

Savington

iTrader: (31)

The turbo is irrelevant. The stock engine can safely handle 225wtq. A low-boost EFR with a soft timing map will make less power than that, so you can safely run a 6258 on a stock engine.

Mech5700

Ok that makes sense. From what I gather, the EFR6258 wouldn't be overkill for my goals then?

18psi

iTrader: (76)

there are no guarantees
and it will likely pop your engine because you'll likely get addicted and keep raising the torque

but yeah, what sav said

Leafy

iTrader: (1)

Didnt someone pop a stock engine with a 6258 on waste gate pressure? I know I was making enough on the 6758 to be pushing it into the danger zone on just a 7psi iwga and the base map timing map from TSE.

18psi

iTrader: (76)

99mx5 did. at 9-10psi or so

99mx5

iTrader: (16)

Mech5700

I know 99mx5 did, but what was his root cause of failure? I have been going thru his thread and it seems like he blew it up and just dove into a full out rebuild. Didn't dwell much on what happened lol.

I did see Brain comment on his timing and AFR's from his log files tho...

Mech5700

lol oh hey there!

I guess now that you are here, did you find out why this actually happened?

JasonC SBB

You should get the fastest spooling turbo for your power goals. If you won't be building your motor down the road, that might be a GT2554 or GT2560.

JasonC SBB

From that page...
What the hell does this mean?:

**will not shuffle in twin turbo configuration like twin garretts** C

99mx5

iTrader: (16)

Too much power + stock engine + heavy foot = boom!
I was around 300WHP and pushing it on the track. Rod #3 was also giving out when #2 let go.

18psi

iTrader: (76)

that looks like a snapped rod.

not much guesswork there.

*edit: he beat me to it.

tasty danish

iTrader: (9)

That's a nod to the RB26 community. The stock charge pipes suck and with larger turbos could cause a condition where turbulence from one turbo undergoes reversion and stalls the other. Since it's essentially surge, it's the same as if you had turbos that were too large and actually surged at idle.

I have no idea why these goofy brits and aussies call it shuffle but just think surge with 2 turbos.

Mech5700

Lol I see that, but 99 gave me what I was looking for... 300 whp on a stock motor on the track, of course it was gonna let go sooner or later!

Mech5700

From what I can tell, this thing starts building boost just over 2k rpm, is that not quick enough?!

And a motor build is definitely not out of the question, just not happening any time soon. *Unless I have to do a forced upgrade like 99mx5 did...

HHammerly

iTrader: (3)

Put your turbo in, get it tuned to 6-7 PSI and start building a short block right away; It only gets more expensive if you just let it blow up when you start crancking up the boost and it granades... You may need a head as well if you wait that long...

Braineack

iTrader: (62)

conservative tune. keep torque under 250.

Leafy

iTrader: (1)

And get the light weight actuator. Which will be blow open at higher rpms by the exhaust, but that'll help you keep the power low.