I got a 3963569 LS6 intake manifold for $220 off Ebay. I ended up having to get a new carb for it anyway (Demon 750 w/ mechanical secondaries). The problem is now, that it does not fit the 454 HO. At least that is what my mechanic says. He said it was about 2 inches too deep. My question is now, have other people running this config removed the oil splash gaurd to make it fit? With the gaurd removed does it fit? Doesnt removing the splash gaurd get the manifold hot and make the carb idle poorly?

I really really want to keep my hood.

THANX
TED

 

I run an LS6 manifold on what was originally a 454 HO but mine came minus manifold and oil spash shield. I made my own spash sheild (make a model in carboard before moving up to aluminium or steel). I think the LS6 is a dog of a design with runners running deep into valley before turning up then abruptly down into ports.

I believe this Offenhauser:
http://cgi.ebay.com/ebaymotors/ws/eB...%3AWN%3AMT%3A1

might be your best bet. Its a different design that gives better entry into port without excessive height and with a good drop down aircleaner might fit.

See also:
http://forums.corvetteforum.com/show....php?t=1014597

 

The exhaust heat into manifold is more influential in adding heat. BLOCK IT. As you dont live in a cold area you dont need it. Sure a bit longer to warm up but better power with the cold manifold.

 

You'd think that in the GM Performance Parts catalog, there would be a description, or a web linkage, that you could go to, to find which cars a 454HO would fit. For GM you'd think that fit information would be very easy, Why don't they do it? For instance, I bought their Serpentine Belt kit and it doesn't fit a C3. (I think I could realively easily made achining modification to make it fit.) I wish they would provide more detailed fit information. I'm sure with their expert knowledge, and being able to access computerized blue prints, they could realitvely easily provide this information. ..Or at least provide outline/envelope drawings.

This lack of fit information is not limited to the GM Performance Parts Catalog. When looking for crate engines, I ultimately ended up trying to contact one of the really high price crate engine vendors. Their crate engines for SB engines go up into the $8000 to $10000 regions. I had trouble getting them to answer Emails and also trying to get them on the phone was really difficult. Finially I got someone from tech support. I asked if their such and such engine would fit a 1968 Corvette. I heard a bored voice say he didn't know, he thought maybe it would not. I said, well I have a BB hood, will it fit, he didn't know. The tech advice was basically a take it or leave it attitude. I was invited to come to their show room and make measurements of an engine in the lobby they had on display. Since they were in the Torrance, Ca area, I drove over. The lack of information really was a turn-off. Sometimes vendors make it so difficult to spend large amounts of money!!! Anyhow, I bought a ZZ4H from Scroggin-Dickie. They were really very helpful. I think I would have possibly been happier with the performance of the higher priced custom engine, but I just was not going to be humiliated with their selling attitude.

 

Thanx Simmo,

I had not heard of the Offenhauser manifold, nor had I seen the thread you supplied. Now I have more research (thread searching to do). Ill have to see if the LS6 will fit without the splash gaurd, and look into blocking the crossover.

Every time I have a question about my vette, I am blown away as to how much information there is on this forum.

TED