Are these manifolds better than stock?

[Skyhead22]

What is a GIL exhaust manifold? Including a picture. Will these provide better flow for a built engine? Rather than having a water hose top and bottom, it has a loop on the top and only 1 water line hooks to the bottom of the manifold. They have a y-pipe (not pictured) to hook the 2 water lines into 1 line where they would both originally fit onto the manifold (1 top 1 bottom). But this manifold setup turns the 2 lines into 1 line and it hooks up at the bottom. Why is this?

 

[Skyhead22]

If they meant for high performance why on earth are they designed to not accommodate high rise valve covers? I'm forced to use roller tip rockers rather than full roller with standard height valve covers.

 

[Skyhead22]

I cannot find these manifolds anywhere at all using Google! I can find them similar for big block only. What the heck??

 

[Skyhead22]

Really hope somebody replies soon! I'm going nuts I cannot find a set of gil exhaust manifolds built for a small block any where on the Internet yet I have a set sitting right in front of me!?!?

 

[NHGuy]

Hi, Gils are better.
You can fit roller rockers under a short valve cover, but if you want to go all stabilized valve train you might want to arrange some sort of exhaust manifold fat gasket/spacer to get the mani's out far enough for tall covers. Or try to find some tall covers that curve at the top.
I put some aluminum rollers under some OE center bolt covers. Had to cut out some of the interior structure to fit the rockers. That engine is still running the same way 4 years later.

If you plan to go high performance and run extended high rpm look up your ring gaps and open them appropriately. Also consider short travel or solid lifters. Standard lifters can pump up at extended high rpm and bleed off your compression.

That water system is great, the cooling liquid goes in the bottom and out the top. Don't worry. It's significantly better that stock.

 

[NHGuy]

The Gils are mainly better because you can run more cam. OE risers revert water at idle if your cam is too aggresive. The Gils,and all HP marine exhaust, add the water to the exhaust downstream. That means at idle the water is farther away from your valuable engine. And has farther to come to cause troubles.
Check out Comp Cams marine stuff. They give you info about which cams are OK with stock risers. From that you can work out your own choice of which suits your design. Doesn't have to come from them, but the info is a little easier to digest than some other sources.

 

[alldodge]

I cannot find these manifolds anywhere at all using Google! I can find them similar for big block only. What the heck??

Edit: take that back you trying to find Gil V6 exhaust, and I don't think they make them anymore

You didn't get much response probably because of when you posted, it started at 1053PM EST, folks probably sleeping.

There are also other brands as EMI, Stainless, and others. The performance exhaust use dry joint fittings as NHGuy mentioned to help keep water away. The newer Merc exhaust uses similar setup

 

[Skyhead22]

No Title

Edit: take that back you trying to find Gil V6 exhaust, and I don't think they make them anymore

You didn't get much response probably because of when you posted, it started at 1053PM EST, folks probably sleeping.

There are also other brands as EMI, Stainless, and others. The performance exhaust use dry joint fittings as NHGuy mentioned to help keep water away. The newer Merc exhaust uses similar setup

.....

 

[alldodge]

Guess I'll take back my take back. I googled "gil exhaust" and came up with a full page, here is the first on the list.

http://www.cpperformance.com/products/exhaust/gil-exhaust.htm

 

[Skyhead22]

Ya I've found all I can that they offer. I got ahold of the guy who I got them from. They have since discontinued their small block line. Stinks. Just having the engined freshened up that they were on. Cam .218 .224 duration at .050. Hydraulic roller. I've read .230 duration is the max to avoid reversion. I'm contemplating going larger if the manifold design allows for it.