I have ran a 3 mm inlinepro headgaset on my stock motor for 3 years with several autocrosses on it. My motor still seems to be in good shape. The boost is set at 10lbs.

 

So many of you have used just the thicker HG? What about ARP headstuds and a block guard? I know these are extra precautions, but I just thought they go along with a thicker HG.

 

doesnt cometic make like a .057 and a .045 or sumthing like that and where do u purchase it at?

 

Inline Pro states that the 3mm gasket will lower a JDM B18C to 9:1. I am completing mine currently. For added assurance and since you have to replace the head bolts anyway, I decided to go with ARP head studs and Inline Pro block gaurd at the same time. Anyone using this same set up should be able to run 10-12 psi safely, considering the motor is sound. People are running up to 15 psi on similar set up without problems when properly tuned (hondata, AEM). I can't wait to put down 280-300 whp with my budget build and the GReddy 18g kit/650cc/Hondata. It should pull hard.

Further, I believe others who are building the bottom end w/o sleeving are limited to 15psi safely anyway. So what's the difference? About $2000.

 

Oh, but what's the deal with the cam gear adjustments? My timing marks lined up perfectly with the 3mm gasket. I know someone mentioned 2deg advanced int/exh. Any more input on that?

 

since the gasket is thicker, the cams are going to cause the valves to open and shut at different times now, so a little bit of adjustment may be needed to get them back to how they opened and shut with the oem gasket

 

My rule of thumb is for every .010" you add to the head gasket, you decrease compression ratio about .2-1 (two tenths of a point)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">My rule of thumb is for every .010" you add to the head gasket, you decrease compression ratio about .2-1 (two tenths of a point)</TD></TR></TABLE>

And 12 degrees of timing?

 

Is there some type of formula to figure cam timing adjustment to compensate for the thicker head gasket?

 

one degree for every .012" of change.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">one degree for every .012" of change.</TD></TR></TABLE>

Boy was it late when I posted that and I was BASS AKWARDS AS HELL!

 

O.K., thanks for the formula. What if my timing marks line up though. I have the InlinePro 3mm and my timing marks still line up almost perfectly. Is adjusting the gears still necessary?

Wait, according to that formula of .012" = 1deg adj, then 3mm = .11811", so .11811"/.012" = 9.8425(deg)

That's almost 10 deg of adjustment! Is that right? Wow, that seems like a lot. I think I did the math correctly.


Modified by ocd at 8:38 PM 9/30/2004

 

bump^

 

thanks for the bump ocd glad some1 else is interested in this too

BTW if using a gasket u lower the compression to say 9.01 how much boost could u run under it because im hoping to run 1 bar (any1 run that much or more boost dnt wanna b the first to try it and blow something )

 

^^^^^^

 

you may want to understand a concept called "squish" or "quench". Old timers call it mechanical octane. Quench pads on the piston working with the chamber is the single most important factor in engine design.

CR does not make knock. Chamber/piston shape cause knock.

When one begins to try understanding flamewave travel, they rapidly see how foolish anything that removes the ability for squish to occur truely is.

PS, 11deg per tooth, if you have a 9deg shift, you put your timing belt on off 1 tooth. It will still look nearly perfect when you do that, and it actually is nearly back where it was stock.

 

^
That's interesting stuff. So as I understand it, squish or quench, refers to chamber design at TDC. Is this true? Then I can assume that mechanically lowering the C/R of the cylinder with a thick head gasket actually changes the chamber structure and shape at TDC. Is this what allows higher forced induction pressures to be run?

I don't think anyone has answered the question about the cam timing adjustment with the 3mm head gasket. Here is what is going on. The manufacturer of the 3mm gasket told me I would need to adjust my cam gears (adjustable type) to have the engine timing correct. The 3mm gasket will offset the timing marks. My concern is that all the timing mark are almost on point. Only the crank mark seems to be off very slightly. From my experience, B-series honda crank marks are usually of by a little bit anyway.

So, if my timing marks line up, is it necessary to adjust the cam gears? I don't understand what I am compensating for. Basically, the timing marks are lined up.
Anyone?

 

^^bump, bump

 

I'm lost on your math and situation.
If you milled .020" off your head and put a .020" thicker head gasket in place, your net result is zero change and no adjustment would be necessary.
Basically you want all 3 marks to line up at zero when you do your install. You may have to adjust your cam gears slightly to do that base on any head milling, any block milling and/or any head gasket thickness change.
If you are a tooth off, something is wrong.

 

Can you give us a more detailed explanation on flame travel, quench and how it affects the B series engine.
BTW, Art talks highly of you

 

The head/block are not milled at all. Stock spec measurements. The situation is I have been told that adjustable cam gears are necessary, when using a 3mm head gasket, to compensate for the engine timing being thrown off. I have a B18c with the 3mm gasket and my timing marks seem to line up just right (only the crank mark is very very slightly off). Why do i need and have to adjust my cam gears? The factory timing marks are lined up with the 3mm gasket in place. Is there something I don't understand?

 

bump^

 

&lt;---- 3mm inline pro head gasket and block gaurd on a 98 USDM stock ITR block. I run .9bar daily and 1.1 bar at the track on 114octane. I have a 18g turbo, afc, missing link, 450cc injectors, cartech FMU, 255lph fuel pump tuned very rich....the block has 91k miles on it.

talk to jinxproof he knows a lot about the inline pro head gasket. I also think stan from inline pro did a low 11-high 10 on his stock block with their head gasket and block gaurd

 

Sorry for bringing this back but i would like to know about the timing issue?

Is it a must to use cam gears with a 2mm gasket on a B18c1 and if so could i set it to 0 until i get it tuned? Thanks.

 

i was able to get a .074 thick HG from cometic.