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LGAFF · 01-05-2015

The LT-5 Plenum is know to be too small.....on a manual trans car you really want at least 1X the CI of the motor, some say 1.5X. I also know that in testing larger plenums did better during engine development....approximately 55-80 additional cubic inches are needed.

A lot of people told me the plenum roof would not clear the hood, however I have 1.14inches in the front and 2" in the back. I think the issue is raising the entire plenum and not just the plenum body....the runners might hit the outside of the raised section of the hood; but the plenum box has room...I also have no AC.

I would like to have unshrouded the #7/#8 runners but the fuel rail is a challenge

01-05-2015	#3
LGAFF Join Date: Mar 2007 Location: Crystal Lake, IL Posts: 7,191	Re: Frankenplenum The LT-5 Plenum is know to be too small.....on a manual trans car you really want at least 1X the CI of the motor, some say 1.5X. I also know that in testing larger plenums did better during engine development....approximately 55-80 additional cubic inches are needed. A lot of people told me the plenum roof would not clear the hood, however I have 1.14inches in the front and 2" in the back. I think the issue is raising the entire plenum and not just the plenum body....the runners might hit the outside of the raised section of the hood; but the plenum box has room...I also have no AC. I would like to have unshrouded the #7/#8 runners but the fuel rail is a challenge __________________ LGAFF 90 #966-150K miles-sold 92 #234-sold 1987 Callaway TT #17 1991 ZR-1 #1359 Last edited by LGAFF; 01-05-2015 at 10:43 PM.