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[guppytrash]

I know there are a bunch of you that have used the .030 Cometic head gasket.
I am thinking this with the Fueling 574 cams and new lifters.
So my 2 questions are:
1. Is everyone happy with the results of the head gasket change.  Meaning you have had no ill affects... leaks, detonation,etc.??
2. Should I use the Fueling lifters?  Is there a best lifter for reliability? 
 

[2018_FLTRXSE]

No leaks, or pinging... the increase in statinc CR is a nice improvement...

[Ghost__Rider]

I've done 8 bikes with Andrews 54's, stock push rods & Cometic .030 HG's . No leaks and no pinging. I have no complaints and wouldn't hesitate to do more.

[Big C.]

  Just my .02 but from my research I have been told by many knowledgeable sources in and outside of this forum that the performance gain is so nill its not worth pulling the heads to just change to a .030 gasket.  If you decide to have your heads done then it's worth changing.  Do the cams and get it tuned and when your ready to go further start with the foundation and have the crank done and work up from there.  Oh if you have your heart set on fueling check into one of their full camchest kits, lifters, cams, rods, pump, and support plate.

[timtoolman]

get new outside sources

[MUFFMAN]

By going to the 030 cometic head gaskets you will increase combustion efficiency & the bike will burn the fuel better as well.  just my 002cents

[grc]

Just a rough estimate, but I'd guess that all you would gain in terms of static compression ratio by changing to that slightly thinner head gasket would be a couple tenths.  Not exactly worth it in my humble opinion unless you plan to pull the heads for something else anyway.  As a stand alone mod, it is definitely not worth the labor expense.

If you're doing cams and the grind you have your heart set on requires 10.5:1 CR for instance, you ain't gonna get there with a gasket change.  Bite the bullet and do it the right way.


Jerry

[Big C.]

get new outside sources

Any recommendations?

[Unbalanced]

Wouldnt use the fueling lifters personally, rather use the 99b's.   They have done well for me in all sizes of motors including 124 and my 131.

Rather than just pull the head for a gasket I think most people would be better served to find out how far in the hole your pistons are and correct your deck height to a 0 deck height.  you may also want to have the bore checked on the cylinders to ensure they are round, if they aren't you could have them mill the necessary amount whether it be .005 or .010 over and put in new pistons while your there too.  This differs on builder preference, but most of mine have been .0025 piston to wall clearance some like .003 or more for street applications.

Since the heads are off you might see if one of the named porters has an exchange program to limit your down time and thus you dont have 3 - 8 weeks of down time.  0 deckheight, proper squish, 030 headgasket and some compression and good flowing heads will make a nice package.   I typically shoot for around 185 cranking compression and move on down the road.

Also note if you are changing the cams, check the runout of your crank while you are there before you install the new cams.

[Fullsac Performance]

I know there are a bunch of you that have used the .030 Cometic head gasket.
I am thinking this with the Fueling 574 cams and new lifters.
So my 2 questions are:
1. Is everyone happy with the results of the head gasket change.  Meaning you have had no ill affects... leaks, detonation,etc.??
2. Should I use the Fueling lifters?  Is there a best lifter for reliability? 
 

If your going to reuse the stock pushrods, the gasket swap is only another hour labor. The tighter squish is what your after.
The power increase is slight, but chamber efficiency is up with less tendecy for detonation. If your going old school with the bolt cutters and
adjustables, don't sweat it. The extra clickity click from the heavier pushrods will cover up any slight pinging.

SG

[HILLSIDECYCLE.COM]

The closer you can put the piston, to the cylinder head, during normal engine operating temps, the less chance of detonation you will experience.
We used to run .018", @ 17.25 cr, on our 108" AHDRA Mod Class racer, w/o head gaskets, with precision 30* angles on both head, and pistons, but that was a different breed of cat.
Scott

[SBB]

We used to run .018", @ 17.25 cr, on our 108" AHDRA Mod Class racer, w/o head gaskets, with precision 30* angles on both head, and pistons, but that was a different breed of cat.
Scott

17.25 cr!
Bet that took a remote starter to crank it.
What 1/4 mile times Scott?
Any pictures?

SBB

[FAST380]

Is there an obvious physical difference between stock and the .030 gasket? I just wonder if a HD tech would notice this if there was an engine problem down the road. This is the first bike I have ever owned with a warranty (7 year), every time I take it in I am sure they are looking for a way to screw me..... hope I am wrong!!

[Unbalanced]

They would notice the cometic from a stock harley one. 

[Fullsac Performance]

The closer you can put the piston, to the cylinder head, during normal engine operating temps, the less chance of detonation you will experience.
We used to run .018", @ 17.25 cr, on our 108" AHDRA Mod Class racer, w/o head gaskets, with precision 30* angles on both head, and pistons, but that was a different breed of cat.
Scott

I set up a lot of water cooled two strokes back in the day at .025 squish. It would just clean the carbon off the piston top. The barrel height on the cast iron water cooled two strokes did not grow much if any. We buzzed em 9500 RPM. Between piston growth and rod stretch .025 was all used up.
How tight do you think an air cooled street ridden Harley could run? These things have to grow taller as they heat up. Maybe .030 is conservative?

Steve George
Fullsac Performance