Any 40R #s yet?
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Joined: Dec 2002
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From: cali
T66 1.0 Q trim is good for 500rwhp @25psi on a street ported motor , Chris Roths ITS67mm DBB(basicly a pt67/TO4R makes 467@19psi on a large street port with a .84 hotside fully divided. The 67 flows~5-10% more than the 66.If you don't mind the revs, try the GT40 with a 1.06. What are you looking for ~rwhp? BTW, These turbos really come into their own at 25-30 psi, so those #s can be improved upon. These are hard #s from dynos I have seen. Hope that helps, Carl Byck
FWIW, you can spec a GT40 to be almost exactly a T66 .81 (.84) Q trim. The T66 .81 Q trim is what I am trying, but I am waiting on a .81 Q trim Hot side w/a 4" V band to arrive.
FWIW, you can spec a GT40 to be almost exactly a T66 .81 (.84) Q trim. The T66 .81 Q trim is what I am trying, but I am waiting on a .81 Q trim Hot side w/a 4" V band to arrive.
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Joined: Jul 2001
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From: Cary, NC
Originally posted by in2twins
T66 1.0 Q trim is good for 500rwhp @25psi on a street ported motor , Chris Roths ITS67mm DBB(basicly a pt67/TO4R makes 467@19psi on a large street port with a .84 hotside fully divided. The 67 flows~5-10% more than the 66.If you don't mind the revs, try the GT40 with a 1.06. What are you looking for ~rwhp? BTW, These turbos really come into their own at 25-30 psi, so those #s can be improved upon. These are hard #s from dynos I have seen. Hope that helps, Carl Byck
FWIW, you can spec a GT40 to be almost exactly a T66 .81 (.84) Q trim. The T66 .81 Q trim is what I am trying, but I am waiting on a .81 Q trim Hot side w/a 4" V band to arrive.
T66 1.0 Q trim is good for 500rwhp @25psi on a street ported motor , Chris Roths ITS67mm DBB(basicly a pt67/TO4R makes 467@19psi on a large street port with a .84 hotside fully divided. The 67 flows~5-10% more than the 66.If you don't mind the revs, try the GT40 with a 1.06. What are you looking for ~rwhp? BTW, These turbos really come into their own at 25-30 psi, so those #s can be improved upon. These are hard #s from dynos I have seen. Hope that helps, Carl Byck
FWIW, you can spec a GT40 to be almost exactly a T66 .81 (.84) Q trim. The T66 .81 Q trim is what I am trying, but I am waiting on a .81 Q trim Hot side w/a 4" V band to arrive.
so would the gt40 1.06 88mm 54 trim make more power than a t66? i would like 500+ at 20-22 psi and more if the boost is increased.
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Allrotor, Search CARX7s posts, that is about the max you will see from a GT40R, they are similar in size depending on exact configuration. The T66, and the GT40 are almost identical, but you gain more efficient wheel geometry, a better surge line, and faster boost responce with the GT40 R, for not much more money(than a Q trim). Carl
I switched for a few reasons...curiosity for one and two, the turbine seal went bad on my unit. Not sure why as it's never been under hard useage. I'll be sending it back to Majestic for a diagnosis and full rebuild. I'd also like a bit more response which I'm hoping the more efficient turbine and BB CRHA will provide. Durability too, and it's water/oil fed/lubed/cooled as opposed to just oil only. I know GReddy is big on this but with the extreme temps down here in Florida, me thinks the water cooled center section will be a bonus for longevity. I already know what a great compressor the 40R 88mm wheel is, as do you :-) I figure this turbo will provide the best in terms of streetability and killer top end rush. It'll be interesting to see how the turbine housings compare in size.
LOL, I think Seans going to figure something out for me...my turbo is about to take a big dump and go to turbo heaven. Thanks to the leaking rear turbine and my vented hood, it looks like I am purging huge quantities of nitrous every time I leave a stoplight. Except it smells like oil


