Im so glad i never found out that RS makes the cylinders 3 thousandths higher than the block deck. I found out when i went to start up my car and blasted coolant from under the head.

I called Earl and he informed me about the Cylinder situation, so i pulled the head and looked at the cylinders, and indeed they were higher. So he told me to get an Cometic MLS and everything should seal up fine.

Does anyone have experience with this?

 

Why not go with an OEM head gasket?

 

Yeah you should never use a Cometic HP gasket with a Stepped deck or O ringed block. I found thisout a long time ago when I got my Golden Eagle block, they informed us if you we keep the step deck use the Cometic MLS or Factory overbored gasket, this goes for all stepped decked or o ringed blocks. Change the gasket and good luck! Easy fix though. At least it wasn't anything major.

 

So idf i get a factory head gasket can it be bored to 85mm? Or should i just get a MLS 85mm?

Its an ITR, so i dunno if the B20 head gasket will have the proper "holes" oil pasages and coolant etc.

 

GEM offers overbored head gaskets. I have one for my 84mm B16a. I'm not sure about 85mm though. BoostFed probably knows.

 

Yeah they offer basically any bore you need but also RS Machines has overbored Factory headgaskets too. You want a VTEC headgasket that is overbored. I use and have used Cometic headgaskets but will admit that they are not the same as stock, I like mine because it is a Cometic HP with the extra fire ring for high boost apps but they are a bitch to get on the dowel pins on some and others they are easy so it shows that each gasket is different. The tolerances are not as precise as stock but ARE still great imo.

 

So whats the verdict? Cometic MLS or Factory overbore?

 

Either will work well. You could probably get the Cometics quicker, however.
BTW, which gasket did you use and what pounds did you torque the head?

 

I've been through both and the factory overbore is where its at. Especially if you have a o-ringed block. If not then it really shouldn't matter if you used a MLS, HP or stock. Block being .003 higher really shouldn't make too much of a difference in my opinion but I just don't like cometic as much. They couldn't answer **** for questions when i called them.

 

i used the cometic HP and i torqued em to 65lbs, kinda scared to go to 78lbs like everyone says

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIReg9 &raquo;</TD></TR><TR><TD CLASS="quote">i used the cometic HP and i torqued em to 65lbs, kinda scared to go to 78lbs like everyone says</TD></TR></TABLE>The combination of an o-ring in the gasket added to the raise deck is just too drastic. Use the Conetic MLS or Stock gasket and you should be fine. Keep your head bolt torque to within 5 lbs of stock. Too much torque will warp the head over a period of time.

 

Hey Earl, do you happen to sell either of these head gaskets, I would like to buy from you since you helped me out so much. Let me know, And thanks for talking to me over the phone yesterday also!

 

No I don't sell head gaskets but thanks for asking.
Call Cometic directly 1-800-752-9850, ask for Jason if you want a Cometic.
If you want to use the stock gasket bored to your size, try Vince at GE or maybe RS Machine.

 

Thanks alot, i will hopefully get this cured by the weekend

 

I am running 84mm Cometic MLS with no problems. GE Block.

 

Grave digging on this fine Hump day.

I would like to add to this old thread by saying I had sealing Issue's with an RS sleeved .004 Stepped Deck Block and a Cometic .045 head gasket. The Large center steel gasket did not seal right i guess due to the size. If you are using a Stepped deck motor the Cometic .030HD 3 ply is the biggest head gasket you can use! the next size .040 has this steel center layer gasket and you will have problems. I had to take this block back to RS to double check everything got the head pressure checked and i find myself doing this swap twice. This is the 11th block ive built with RS sleeves and never had this issuse until i started using the larger .04, .051 head gaskets on Boost Stepped Motors. long story short use a Maximum of .030 MLS Cometic or laser cut OE gasket on a Stepped Deck. ive been using Cometic for almost 10 years now and they are Excellent! never any leakage issues. I have decided to Deck this Fresh Motor with only 20 miles and get another Cometic MLS. Thanks for reading.

 

Interesting. Nice bump

I think we used a cometic hp on my build but it was a bunch of years ago so I don't know off the top of my head. Either way. The block has always seemed to seep a bit of coolant from time to time. Thought I had a head gasket issue a couple times but just ignored it since the car didn't smoke or mix fluids...

Starting to all make sense now... Will start digging for receipts.

 

for real bro all making sense like 4 days later, what puzzled me was there was no contamination in the oil or coolant system. never the less you always learn something new everyday and in most cases its the hard way

 

Well, to tell the truth. I have been ignoring the little bit of seepage for something like 6 years so I really can't complain. Motor doesn't smoke and barely works to get out 460whp. Its pretty minor but it makes sense. I know I had been using the cometic hp gasket for years at that point so it is probably what was used. There also was some oil in the antifreeze at first but after a flush had cleaned itself up so I just assumed it was from the build.

 

Ever since I started going to RS, Dave has always recommended OEM hg's or Golden Eagle (which is also OEM).

 

I have a .002 stepped deck b16 and are using the .051 Cometic Head gasket. The engine hasn't been put under any load yet so I'll have to see how I get on.

I needed to use the .051 head gasket as my piston to head clearance was to tight with the stock gasket. If it fails then what head gasket do I go for?

 

3 choices

Cometic. 0030 hd oem gasket

Or deck the block flat like i did and stay with your thick boost gasket

 

I'll see how I get on. I'm only at 81.25mm and I gave the head gasket a coating in Hylomar blue so hopefully I'm OK . If it comes down to it I'll probably just get the pistons machined down a tad and run the stock head gasket.

 

Are these RS sleeves "o ringed" as well? I'm using Darton flanged on my setup.

 

i dont think they are O-ringed. From the way he makes it sounds. He had it stepped , not o-ringed. you really cant do both it would be too high. When i mentioned stepping the block my machine shop wouldnt do it. They were against it so i went with Copper o-rings. I was going to use stainless wire with a reciever grove in head (coppper headgasket) Thats is most common outside of the honda world. Since everyone had great success with copper i went that route. No problems since (besides my cometic head gasket i intially used not pointing fingers but went OEM gasket and zero problems)

Why hylomar blue Vs. Copper spray? Jsut curious. Ive used copper spray but never considered using anything else since copper is great for heat transfer. How will hylomar blue handle those heat conditions? im not familiar with that stuff at all

I hope the Cometic works out for you! If you have issues are you going to go to OEM? Did you have the block milled? why was piston to head clearance to tight? Youre certain you cant use OEM? or just playing it safe?