Advise on turbo size for FM kit on Mazdaspeed
 

Hello fellas I was just wondering If anyone on here has ran a Garrett gt2876r on the Flyin Miata manifold? I've currently got a Gt2560r and I'm about to get the car tuned I've got a person selling me a gt2876r .70 compressor .86 hot side and I was wondering if it will fit with the fm manifold it's ok if I need to notch the frame I've included a pic of my current setup to show what I'm talking about.


https://www.miataturbo.net/attachmen...ine=1398227355

Yes. It will.

you dont want that turbo and you want to keep the 2560.


/thread.

Why do you say that? I'm looking to get around 280-300whp I'm not on built internals yet I do know I'm maxing out my stock internals. But I don't want the gt2560r to be chocking on power or to be at 280-300 on like 25 psi I don't want to be over 16-18psi max

Yeah, and?


Even if it WOULD take 25psi, what does psi have to do with anything?

I don't think the msm motor will handle 25psi

I don't understand what psi has to do with anything.

The MSM motor won't handle 300whp on a 2560. It also won't handle 300whp on a 2876.

What's the question, again?

I like this chain you have going. Reminds me of the old reddit switch-a-roo.

[fedora tip intensifies]

*tip fedora* m'miata. ;)

+/u/dogetipbot 5 doge verify

Are you plain stupid, boy? Or are you just happy to see me?

I have seen a handful of 2560's make 275whp+ on stock motors between 16-20psi. None of them were on cast manifolds though. I honestly would not want to have a 2876 on a log manifold, the spool will not be great at all. You can check y8s old dyno threads and see how his spool was with and without vvt.

I appreciate it! I've made my decision to keep the gt2560 I'm just waiting to receive my Haltech and see what kind of numbers it puts on the dyno.

Once again I gladly appreciate it!

Why boost is meaningless by itself: Its just a pressure, and on the intake side of the engine only.

20psi into a 3L engine from a 40R is probably a lot cooler IAT than 15psi into a 3L from a 2860. In other words, that lower psi 2860 is likely making for a hotter IAT than the 40R at 20 psi.

More to the point, an engine that cant handle 300WHP due to weak rods does not really care if that 300WHP comes from a low boost supercharger or 50PSIG from a GT45. Its still more than the rods can take and the boost pressure does not really matter.

Your engine on stock internals will puke regardless of what turbo you use to hit 300WHP. You could throw some huge T4 footprint unit on there and have the capability of making 300WHP at 10psi and it will still fail. A smaller turbo may make a 'sharper' increase in TQ in certain situations, hastening the fail, but in the end its just going to happen. Buy rods. Ask Miata or 1.8T VW people about this.

I get exactly what you mean great advise! Now how much power is that I should stay around. I'm planning on building the internals and head in a couple of months.

Before or after? Very strange questions considering your background.

What is safe level for a msm engine and what's pushing it and what is too far? I'm talking about whp on stock internals

It's not whp that breaks motors, though.

250ftlbs is the "magic" number. Can get away with more or less depending on driving habits, condition of your motor, and tune.