I'm in quite a dilema. I'm having ETP 215 heads, custom built cam & 150 wetshot added to my car. I originally wanted a LSX fast 90/90 setup but decided to just go with the LS6 intake since it'll be less expensive and alot easier to tune. Now I'm being given an option between two head gaskets which are:

1). Cometic (hope I spelled that right). This is supposed to be the better of the two performance wise. However, I have been fore warned that this gasket is very hit or miss. If you hit your rocking but if you miss your in a world of hurt.

2). Fel-pro. This is supposed to be a quality gasket with no known issues. Down side is It'll leave 20 HP on the table.

Lose 20 horses and feel safe or roll the dice to gain 20 horses? I all ready feel kind of guilty for leaving 15 horses on the table from the LSX thing. 15 + 20 = 35 OUCH.

I originally said to go the safe route with fel-pro but now I'm starting to second guess myself. Can I really leave 20 horses on the table????

What would you do and why?

Thanks,

Darren

 

Cometics are great when your working with perfectly flat surfaces. Some people have had them leak on them while others have not. I just put a set of Cometics on about a month ago (new block & new heads) and they are working just great. Now I did coat them with the copper spray just to be on the safe side.
Fel-Pros are suppose to be more forgiving for slight imperfections.
But as for Fel-Pros leaving 20HP on the table??? I'm not sure where you got that information from but I highly doubt that your going to gain/lose 20HP by using the exact same thickness head gasket but using different brands.

 

Yeah, any differences in power are going to be due to size and not necessarily the brand or material. Also, 20 HP is a stretch.

 

I don't know much about head gaskets but that is just what I was told. 20 HP (not sure if he meant FW or RW) and about 1 mph in trap is what I would be leaving on the table to go the safer route. Whether it's true or not I have no idea. Like I said, I know nothing about head gaskets and the search I did here had very little information to offer.

But thanks for the replies. If the difference between the two is in deed less then 20 HP then I would feel comfortable with staying with the fel-pros.

 

You gotta give us the sizes youre talking about.

Personally, why not go with the GM MLS 6.0L gaskets? Theyre .054" gaskets. Some poeple take their cometics down to .040. That would likely ammount to about a third of a point of compression and a little tighter quench. Togather, id be surprised if it came out to 10 HP. The GM ones are about 30 bucks for teh pair, much cheaper than cometics. Plus it gives you an extra .014 piston to valve clearance for a cam.

 

I'm going with the Cometic MLS Gaskets at .040 thickness.

 

Make sure to pick up some copper spray.