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LS6 vs our stock intake

17K views 30 replies 17 participants last post by  KKDZ28 
#1 ·
stock for stock which flows better the LS6 intake or our factory intake. i have looked everywhere but i can not find flow numbers for our stock intake does anyone have them? what about LS6 flow numbers?
 
#3 ·
When I bought my ls2 intake (car) for a project I did a little reading. Even though the ls2 intake has a larger (90mm) tb bore, the flow characteristics of the ls6 are/were better. With that being said, the (newer) truck intakes have that same size bore. Our intakes make more power down low, as compared to a car intake that makes its power up high. The ls6 intake makes power higher (in the rpm range) than any of the rest, if I'm not mistaken.


Someone correct me if I'm wrong.......
 
#4 ·
The flow #s are actually quite interesting, between the two intakes. They are even until .200" valve lift, then the LS6 shows a 10 cfm gain up to .350". From there to .450" lift, the LS6 is 12 cfm better. Then our manifold recovers nicely and stays within a couple cfm until .650" lift, where the LS6 gains 7 cfm, and that's where the test ended. The #s at that point were 256 cfm for our manifold and 263 for the LS6.

I don't have any data on the LS2 vs the LS6, but all the comments I've seen suggest that the LS6 is slightly better, overall.
 
#16 ·
I know you have stated in other threads that you only flow manifolds attached to a head. For your stated results above what was the CFM of the heads you flowed the manifolds on? I am also curious to know if you have seen the flow of an intake increase with the flow of a head? In theory a manifold would only be able to flow so much air no matter what is pulling on it. But in practice, better heads make more power with the same intake attached. That could be soley due to CFM gains at lower valve lifts under the peak flow of the intake manifold since the manifolds flow is not dictated by valve lift, only flow capability of the runner. I would like to know if you have any data backing either up. I think it would help in head selection or head porting options is one is inclined to port their own heads. Because, if an intake can only flow 256cfm then what is the point of a head under it that can flow 300cfm? I remember working with Brian Tooley about fourteen years ago on this with a L98 SuperRam and Miniram on a set of AFR 210's but I can't remember what we came up with.
 
#11 ·
It's the vette guys! They think their cars worth way more than it really is.
 
#14 ·
I'm using an Edelbrock Victor Jr and am very pleased with it. It could be a great fit for your turbo application! It flows 24 more cfm, compared to the LS6, @ .500" valve lift. The manifold is only around $340 new, but you'll need some type of elbow, of course. It's a racier piece and certainly would have performance advantages over the LS6, though it would give up some low end. Might be worth investigating.
 
#15 ·
What about a ported stocker from peak speed? Would that not flow better than the ls6 and be comparable to the edelbrock intake?
 
#18 ·
I might be able to find you an LS6. Let me email a buddy of mine.

I think it was Matt or some one else on here in the FI section that was against the Vic jr. for FI. Uneven distirbution I believe. The middle four runners end up lean and the outer's end up fat. I think the posted in my turbo build thread.
 
#20 ·
Sorry man, my guy just said the same thing you are saying $350-400 they are in VERY high demand. We stopped using them as cores for porting due to the cost.
 
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