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I am building a 6.0 lq4 ,more for my son than me.
I am kinda relentless and I have been around the block before with combinations. This is a street/strip car. That means 6400-6500 peak power to me with alot of bmep. And great curve
I know a guy did a intake test on here.
I in the process of doing the sort of the same thing.
But I am changing heads and throttle body's and soon intakes as well.
I only checked peak lift flow in these test.
With the truck intake and truck throttle body.
I am so far from where I want to be. There is no point in checking at lower lifts.
No intake , peak lift flow
862. 222cfm
243. 266cfm (with 100% good vj)
862. ported 309 cfm.
Truck intake and truck
throttle body installed peak flow lift
862 222cfm
243 249cfm
862 ported 269cfm. 243 head.
When I set out to do this. I had some different oem heads here I and I knew the shape of the port in the head and its cross section area and the intake manifold and how it aims the air, will change the over all flow curve. You may or may not be suprised by this test.
1st. about my flow bench. Its calibrated with specific orfice plates. Ages ago these plates where sent around and alot of big names tested them. They are dead on. Not going to bore you with calibration details. But when you calibrate a bench you are calibrating the orfice plate and your gauges.
So 1st thing I did was calibrate my bench before this test Hasn't been calibrated in a while and my kid and his friends use it as well. Bench was about 4cfm off.
So I tested a stock 243 head with and without a TBSS intake manifold. And I also tested a 862 head with Minimal port work and a 2.0 sealed power rebuilder valve and 3 angle vj. Nothing crazy.
.This is NOT even my good 300cfm plus 862 port.
If I had to guess the port volume in this 862 port is 208cc. It's not fair to do this test with the 862 having a 1.89 valve, its just terrible like that.
what I am trying to show you is.
The truck head flowed way more with intake than the 243 with the intake. Same valve size, about same runner volume. I am not suprised.