07bluelbz

iTrader: (1)

I have an LS1 block and just put a ls6 valley cover on with my stock ls6 intake and I used the bolts pictured above and had no clearance issues other than having to clearance the block as shown in the LS1 how to article.

Paul Bell

iTrader: (9)

Illegal, revisiting your original post, it looks like the valley cover was fitted properly. Plus, as it's considered a LS6 block, it should be able to fit a LS6 valley cover without clearancing the block.

I suspect the vacuum leak you describe in not related to the intake manifold being sealed to the heads.

Have you examined the fittings on the rear on the intake where the MAP, brake and AC/heating vacuum lines go?

sjsingle1

iTrader: (1)

you did not mention.......where is the front vacuum port on the LS6 VC plummed to ?

vatechguy3

iTrader: (4)

any updates?

tony

Illegal Vette

So I made a discovery today, I had the intake manifold and valley cover off because of an unrelated problem and found 2 of the big square gaskets for the valley cover, the old one and the new one. I clearly put the new one on top of the old one not knowing what I was looking at. This caused a cascade failure of issues, vacuum leaks, interference fits etc. I have no excuse, just a big old fail.

Paul Bell

iTrader: (9)

Hey that's great that you found the problem! Sometimes it's the simple things.

Years ago, I was doing a quickie oil change on my car in a friend's shop. I didn't realize the oil filter gasket stayed on the engine and on start up, it blew out spraying oil everywhere. Some mistakes you make only once.

KCS

iTrader: (20)

Cool, good to hear you found it.