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Need a new cam for my banks twin turbo set up 12 to 15lbs of boost!
468 7.5 to one
merlin cast irons
 

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I ran an Engle TCS-7 in a similar race aero setup.
 

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Why do you run such a low static compression ratio?
 

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The lower the static , the more boost you can get away with before you get into detonation.
Important when trying to run pump gas.
That is true, but you don't need to run as much boost to make some power, and you sacrafice bottom end power with the lower compression.
 

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That is true, but you don't need to run as much boost to make some power, and you sacrafice bottom end power with the lower compression.
Exactly what I was thinking, I would think it would be quite the turd trying to come out of the hole at 7.5 to 1. I am at 8.6 right now and wish it was 9.0! A few guys this last weekend were at 9.2 running 12psi on 92 all weekend long with zero problems.

Travis
 

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I hope to run 10.2 on E-85 with mega boost.
 

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Guess those must be EFI deals that were carefully tuned. I would never recommend that much boost on pump gas on one of the carbed deals.
They were big inch big blocks 548 ford and 598 chevy with chillers, roots blowers and twin dominators. Right now I am running 14psi on 92 with 30* timing locked and a PT2000 air to water cooler, being a blow through set up I can get away with a little more as well. A few guys with blow throughs and big coolers are running 20psi on 92 with no problems.

Travis
 

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That is true, but you don't need to run as much boost to make some power, and you sacrafice bottom end power with the lower compression.
Exactly what I was thinking, I would think it would be quite the turd trying to come out of the hole at 7.5 to 1. I am at 8.6 right now and wish it was 9.0! A few guys this last weekend were at 9.2 running 12psi on 92 all weekend long with zero problems.

Travis
Guess those must be EFI deals that were carefully tuned. I would never recommend that much boost on pump gas on one of the carbed deals.
Exactly what I was saying, my deal is only 7.8-1 , but the boost comes in quick and it comes out of the hole pretty hard. I'm only running 12psi on 91 right know but could probably get away with 15psi or so if I kept an eye on the tune.
Just my .02 so take it as you will but I'd think that you'd make more power with a 8-1 engine with 12-15psi on 91 pump gas than you would with a 9.5-1 engine and be limited to 7-8 psi of boost.
Also if you really want to wake it up down low, just put a small shot of nos on it with some good adder fuel, then you'll be real happy with the lower comp. and make an azz load of power.
 

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AKA Blownjet 468
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I've got a Crower solid roller for a twin turbo application for sale on racing-
better yet, pm me if your interested, 114lc , 686/629 etc......:)
 
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