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WydRyd WydRyd is offline
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Join Date: Mar 2002
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Candy is right... decide where you want your power-band and then match a turbo appropriate to that application. Smaller A/R's will move the power-band lower in the rpm range, but will top out sooner, whereas a larger A/R will move the power band higher up the rpm range but will sacrifice responsiveness in the lower range. It's all a compromise.

My headers has a divided collector, so I decided on a divided inlet turbine HSG to match the header design. It's suppose to improve response/spool-up and I've been pleased with the results. Car is purely street and what minimal lag IS there is negligible.

A GT30R has a 500HP capable compressor, but on an older 911 motor, you're looking at around ~420HP capability. This is perfect for your application and will provide a very streetable setup. It will get up and go very nicely. If you want a bit more top end HP and sacrifice a little bit of response (it won't be much), go with the GT35R. That will give you up to around ~510HP capability and won't run out of breathe in the upper RPM band

OR, if you want to go a bit crazy, go with a GT40R for ~600HP capability. It won't be as responsive, but you'll make a tonne of power You can expect full boost to be in the high 3K rpm range I'd say, but it will give you a nice punch in the chest when it kicks in The 40R isn't available with a T3 HSG, so you'll need to modify your headers with a T4 merge collector to run that baby.
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition
Old 04-28-2007, 03:15 PM
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