Primary size vs collector size
That being said, I would try get the right size collector for the primary you are running. A good collector with a converging/diverging exit makes a notable difference in power. I played with this on a dyno some years ago, and the difference a good collector made were really surprising.
Joined: Apr 2006
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From: Grand Rapids, Michigan
Turbos work with heat, not exhaust velocity. You need a certain size not to choke the engine, but it's not nearly as critical as it is with an N/A, nitrous, or supercharged combo. Case in point, there are guys who have ran well into the 8's in the 1/4 mile using stock truck manifolds. Overly large primaries and collectors aren't needed when the choke point is the turbine housing on the turbo. Sizing those too large only adds to the surface area where heat can dissipate, and you want to retain as much heat as you can pre-turbo.
That all being said, as LS1formulation said, a turbo messes all this up and on a street/strip car you are usually better served picking something that fits nicely and keeps the turbo as close as reasonable to the engine.
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I truly appreciate all of the knowledge this forum has to offer.
I am planning to use the car occasionally in nice weather and giving Roll Racing a shot.
My intentions were twin 6766 vband due to clearance, 2.5 each to the intercooler, 3.5 out.
Any advice on primary, collector size, turbo size & A/R, hot piping would be a Godsend.
Thanks in advance for the help
I am planning to use the car occasionally in nice weather and giving Roll Racing a shot.
My intentions were twin 6766 vband due to clearance, 2.5 each to the intercooler, 3.5 out.
Any advice on primary, collector size, turbo size & A/R, hot piping would be a Godsend.
Thanks in advance for the help
