Advise on turbo size for FM kit on Mazdaspeed
#1
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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.
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#14
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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.
#15
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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.
Once again I gladly appreciate it!
#16
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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.
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.
#17
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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.
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.