Why 10psi?
06-13-2009, 01:15 PM
#7
Limited by turbo.
The little IHI RHB5 has incredible spool characteristics, but for the volumetric flow rates of even the 1.6L at redline this turbo falls off the deep end of efficiency past 10psi.
I could turn it up (to 11...these go to 11), but IATs would surely go up, and the rotating assembly would be at the top speed line of the compressor flow map.
10psi is nice though. It's certainly fast enough on the road. I walk G35s, Mustang GTs and dust F-bodies. I hung with a GTO yesterday despite some ignition problems over 5500rpm (had paper plates, guy obviously couldn't drive). This is probably a wee bit over 200hp on my setup (I envy y8s), which keeps me in safe territory for the rest of the drivetrain. I still have an open 6" diff and stock 5spd.
We do build for headroom for a reason though. If I ever get a torsen the next step will be a compressor swap. Nothing else in my setup would have to be upgraded.
The little IHI RHB5 has incredible spool characteristics, but for the volumetric flow rates of even the 1.6L at redline this turbo falls off the deep end of efficiency past 10psi.
I could turn it up (to 11...these go to 11), but IATs would surely go up, and the rotating assembly would be at the top speed line of the compressor flow map.
10psi is nice though. It's certainly fast enough on the road. I walk G35s, Mustang GTs and dust F-bodies. I hung with a GTO yesterday despite some ignition problems over 5500rpm (had paper plates, guy obviously couldn't drive). This is probably a wee bit over 200hp on my setup (I envy y8s), which keeps me in safe territory for the rest of the drivetrain. I still have an open 6" diff and stock 5spd.
We do build for headroom for a reason though. If I ever get a torsen the next step will be a compressor swap. Nothing else in my setup would have to be upgraded.
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06-14-2009, 02:52 PM
#12
Cpt. Slow
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What PSI are you running through the greddy for 247hp? I still really need to get mine dyno'd, I vary between 6 and 10psi depending on how how well the rest of the setup is working, I really need MS.
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06-14-2009, 03:16 PM
#14
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The greddy is not so puny compared to some of the turbos guys use in miatas.
I run 10 psi because I wanted headroom and reliability... and because my original plan had been a goal of 8 psi - the 10 psi I have now make sthe car quite quick... but the reality is, with every component I put together for this setup, given a motor that could handle it and the right turbo I could do 20, so I think I'm going to bump up to 13 or 14 soon... even though it's the stock motor, some guys are doing 16-18 on the stock motor so.. why not?
I run 10 psi because I wanted headroom and reliability... and because my original plan had been a goal of 8 psi - the 10 psi I have now make sthe car quite quick... but the reality is, with every component I put together for this setup, given a motor that could handle it and the right turbo I could do 20, so I think I'm going to bump up to 13 or 14 soon... even though it's the stock motor, some guys are doing 16-18 on the stock motor so.. why not?
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06-15-2009, 01:53 PM
#20
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220rwhp @ 13psi using my Greddy, but I need spark tuning for moar powar.
10 psi feels good, 13 better - when you have an EBC, Link ECU and 550 injectors more boost is simply a case of dialing in higher numbers.
10 psi feels good, 13 better - when you have an EBC, Link ECU and 550 injectors more boost is simply a case of dialing in higher numbers.
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