Turbine Housing Porting - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

CamaroCracka · 11-28-2021, 08:27 AM

I want to make any improvements I should before I put this back together, and one of those is porting the turbine housing to increase flow.

Engine is LS3 with forged pistons and rods and cam specs are in my sig.

I just got the Comp Turbo 78/80 and see that there is about a 1mm lip on the turbine exit behind the weld line. I'm thinking that lip should be smoothed. That is the easy part.

The housing is a divided T4 and I know I should at least grind that divider to a dull knife edge. I'm thinking I should also at least port match it with the gasket.

The real question is how much should I mess with that divider or the turbine housing ports. The divider goes all the way into the turbine housing so I can't imagine getting rid of it completely, but I'm pretty sure I had back pressure issues with the 76/75 and am wondering if there is any benefit to removing some of it or porting the T4 side of the housing. What is the potential downside?

The turbo manifold is divided up to about six inches from the flange and then the right and left side combine before going into the turbine housing.

Before anyone asks why I did not get a bigger turbo, the answer is that it the biggest turbo that fits that kit without modifying the AC condenser and/or the radiator. Also, the 1.15 AR housing from Comp only comes divided, there was no other option on turbo housing for this turbo.

stevieturbo · 11-28-2021, 02:54 PM

Get drunk instead, it will feel faster that way.

Certainly it is nice to have it all matched, smooth flowing etc etc. In reality it will make no measurable difference.

RealQuick · 11-28-2021, 06:03 PM

I agree with Stevie…

11-28-2021, 08:27 AM	#1
CamaroCracka Drives: 2010 Turbo LS3 Join Date: Dec 2009 Location: Palm Bay, FL Posts: 2,736	Turbine Housing Porting I want to make any improvements I should before I put this back together, and one of those is porting the turbine housing to increase flow. Engine is LS3 with forged pistons and rods and cam specs are in my sig. I just got the Comp Turbo 78/80 and see that there is about a 1mm lip on the turbine exit behind the weld line. I'm thinking that lip should be smoothed. That is the easy part. The housing is a divided T4 and I know I should at least grind that divider to a dull knife edge. I'm thinking I should also at least port match it with the gasket. The real question is how much should I mess with that divider or the turbine housing ports. The divider goes all the way into the turbine housing so I can't imagine getting rid of it completely, but I'm pretty sure I had back pressure issues with the 76/75 and am wondering if there is any benefit to removing some of it or porting the T4 side of the housing. What is the potential downside? The turbo manifold is divided up to about six inches from the flange and then the right and left side combine before going into the turbine housing. Before anyone asks why I did not get a bigger turbo, the answer is that it the biggest turbo that fits that kit without modifying the AC condenser and/or the radiator. Also, the 1.15 AR housing from Comp only comes divided, there was no other option on turbo housing for this turbo. Attached Images __________________ 2010 SS - On3 kit with downpipe cutout, CTR 78/80, CompCam 239/251 620/632 122+4, E85, Z28 suspension and ZL1 diff with Outlaw axles. Gen6 ZL1/1LE brakes. 2011 Vert - 416/w 230/236 .612/.602 115lsa, 1LE suspension w/32mm rear bar. Z28 diff. ZL1 brakes.

11-28-2021, 06:03 PM	#3
RealQuick Drives: 2010 Camaro 2SS M6 - Intake/Exhaust Join Date: Sep 2014 Location: Bridgewater Posts: 693	I agree with Stevie… __________________ 2010 Camaro SS M6 - 416ci TT 989rwhp/1031rwtq @ 20psi 2014 ZL1 A6 Vert - Headers and CAI

11-28-2021, 02:54 PM	#2
stevieturbo Drives: it changes Join Date: Nov 2010 Location: Norn Iron Posts: 1,126	Get drunk instead, it will feel faster that way. Certainly it is nice to have it all matched, smooth flowing etc etc. In reality it will make no measurable difference.