Is the EFR6258 too much for stock engine?
#25
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It will be difficult/impossible to match the EFR here. The trick turbine wheel reduces rotating inertia and lets the wheel spin up fast. There's no way a 2560R car matches the response. A 2554R car might come close, but give up 100whp on the top end.
#26
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rpm is a terrible unit for spool, miliseconds is much better. Over 4k aint nothing going to spool faster than an EFR I dont care how small it is.
Boost threshold wise, thats the rear question. yeah at 2krpms in 5th my 6758 can make a copule psi, got to give it a second though. But its still able to make stock block breaking cylinder pressure by 3.5krpms.
Boost threshold wise, thats the rear question. yeah at 2krpms in 5th my 6758 can make a copule psi, got to give it a second though. But its still able to make stock block breaking cylinder pressure by 3.5krpms.
#28
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It may be more work than you're looking for, especially as new it isn't much cheaper than a 6258, but it might be worth looking into the Focus ST stock turbo: https://www.miataturbo.net/diy-turbo...ler-efr-79947/
#33
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Here is some spool data I found on the collective spool data thread:
I want your spool data! - Page 11 - Miata Turbo Forum - Turbo Kitten is watching you test compression.
Post 203 and 218
I want your spool data! - Page 11 - Miata Turbo Forum - Turbo Kitten is watching you test compression.
Post 203 and 218
EFR in #203: 6.5 and 12.5 psi <-- this is a 2.0L!
EFR in #208: 4.5 and 10 psi
My 2560 data: 7 and 14 psi.
My 2554 data:
9 psi at 2500 (and 5 psi at 2000)
So GT2560 has better low end than EFR6258 even on a 2.0.
Still a pretty big difference.
Because the 2554 can make more than enough torque to break stock rods, it's a great street turbo for a stock motor. For a built street/track car, I personally like the GTX2863 on paper.
#36
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I don't think I or anyone else really needs any more than a couple psi down there and about 150-160tq, but that much alone would make the car amazing at effortless, quiet (more or less) acceleration.
I dunno
#37
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The car just isnt geared for that. And if it was it would just result in hitting boost on the highway on a slight grade like the td04 2.5L wrx. I feel like the only one around here that thinks stock power is perfectly adequate for driving on the street. And fun, you get to feel like boy racer reving to 4k just to accelerate with the rest of traffic and no one knows. But yeah the racecar has noticeably more pickup even at 2k rpms once the tarbo went on compared to N/A.
#38
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The car is absolutely geared for that. I have literally been driving this way since I got it years ago. 6sp+3.9+45mph streets most the way there, means i'm in the 2500 range almost always if I don't rev it out like a boy racer. And even when I get on the freeway I can shift at 3k and still merge on and if I keep it at 65 (I only take the freeway for 1 exit, or 1 mile) its still close to 3k.
The older I get the more appealing a corvette powerband becomes to me. I loved driving the vette to work - get pushed back in your seat and still only turning 2k rpm, and making no noise.
The older I get the more appealing a corvette powerband becomes to me. I loved driving the vette to work - get pushed back in your seat and still only turning 2k rpm, and making no noise.
#39
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The car is absolutely geared for that. I have literally been driving this way since I got it years ago. 6sp+3.9+45mph streets most the way there, means i'm in the 2500 range almost always if I don't rev it out like a boy racer. And even when I get on the freeway I can shift at 3k and still merge on and if I keep it at 65 (I only take the freeway for 1 exit, or 1 mile) its still close to 3k.
The older I get the more appealing a corvette powerband becomes to me. I loved driving the vette to work - get pushed back in your seat and still only turning 2k rpm, and making no noise.
The older I get the more appealing a corvette powerband becomes to me. I loved driving the vette to work - get pushed back in your seat and still only turning 2k rpm, and making no noise.