Does anyone know what Cometic head gasket to use with the Dart205cc heads?

Bill

 

Agree. The CC is 3.970 at the widest point so the GM 6.0 MLS will work fine. Head gaskets Dart recommended to me in order of preference:

1. Fel Pro 1161L and 1161R
2. GM 6.0L MLS
3. Cometic

Bill,
You need to call Cometic and discuss the requirements to find out which gasket best fits your needs.

 

After calling Dart, and not getting much help, I called Cometic, and they specified one they make that is for a 4" bore. Part # H1295040S but keep in mind that is for a .040 gasket thickness. I layed a set of Cometics for a 3.901 bore on my Dart heads and they do overlap the chambers. I don't know if it matters any, but my heads have also been milled to 59cc's.

The only thing I could get out of Dart is that gaskets for a stock bore will not work correctly on Dart heads. I even layed down a set of GM MLS gaskets on my Dart heads, and even they overlap the chambers.

 

Would I have to get that gasket from Cometic direct? I do not even see that part number on their web site or anyone's web site. Sounds like a special order. Did they tell you?

Bill

 

I would recommend just using OEM replacements for your 5.7 Ls1. They will be the right bore size... Just my 2cents

 

It's not a special order, he said they have them in stock they just don't have it on their website. I talked to Kevin at Cometic. They are $82.85 each I believe.

Well.. it might be the right bore size, but it won't fit the chambers of the Dart heads. Like I posted earlier, I laid a set of GM MLS 3.901 head gaskets on my Dart heads and it still went over the chambers. I know it's not the cheap factory head gaskets that came on our cars, but it's still a GM replacement part.

 

Thanks for the info. I will call them and order a set. Are they 4.100" bore or 4.000" bore?

Bill

 

4.00 bore

 

mr. gasket .040's here... about 2000 miles and no leaks...

 

I know the Fel Pro 1161L and 1161R are 4.100" bore. Did Cometic have a 4.100" bore gasket? They were already closed when I tried to call. They closed at 5:00pm EST.
I just want to make sure I get the correct gasket.

Thanks.
Bill

 

As far as copper spray goes... the best I've ever used is VHT. Way better than mr. gasket or permatex.

 

Where did you get VHT copper spray? Autozone, etc.

Thanks,
Bill

 

Here is the info from Cometic:

H1518SP1040S is the part number you will need. They sell for $82.85 each.

Kevyn Kistner
Technical Sales
Cometic Gasket

Hope this helps someone else besides me.

Bill

 

What is the bore diameter on this gasket?

 

It's all about surface prep and the finish (RA) of the head and block. The smoother you can have the two parts the better the gaskets work for both sealing and preventing blow outs. The copper spray seems to help seal the water/oil passages as it does nothing to help with combustion sealing. I wouldn'tbe afraid to use a light coat of copper spray as insurance.

 

The bore is 4.100" which is the same as the Fel Pro 1161L and 1161R which is Dart's first choice. The problem is the Fel Pro does not come in .040 thickness.

Bill

 

Yep, tell me about it. I went with the Fel Pro as recommended by Dart.

 

Thanks everyone for your input. .040 gaskets ordered. I can live with 89% with no leaks.

Bill

 

I had Cometics leak on my stock block and yes the block and heads were meticulously prepped and the gaskets were sprayed with copper spray. I'm not having any problems on the 403 with the .040 Cometics. Fingers crossed.

 

transfers heat well. copper coat is some good cheap insurance.