KleenKrew

I did a head gasket for a guy on a 99-00 civic. It has the injector air bypass stuff on it. Anyways i uses a hondata intake mani gasket. I have it super tight and i still have a nasty vacuum leak in-between the head and intake mani. I feel like ive done everything right i just dont have much experience with these year d series motors. Any suggestions/advice would help. Its just a super nasty vacuum leak.

beecee18

I dont really feel like that setup needed that mod unless you had an issue with intake air temp which ?

that paired with a bunch of people having sealing issues with them, or they develop vacuum leaks after time make it a nono in my book,
check both of the mating surfaces of the cylinder head and intake manifold and check for flat/true as some busters like to use flap disks to remove intake manifold gaskets in production atmospheres. And after that checks out obtain a OEM honda intake manifold gasket. Very unlikely but also check manifold for cracks/leaks ect.
hope this helps.

morbius18

I had the same problem with mine. It wouldnt seal correctly. I replaced it with a paper one and no problems at all. I trashed the thermal one and took the $40 lesson.

KleenKrew

The reason I put head gasket and hondata gasket in is because the kid is going to turbo the car next he was adamant on using a thermal gasket. I think I'm going to try and let it get hot and tighten the **** out of it

beecee18

I dont see that mod netting you any power in the longrun,
other than a host of problems, and 40$ missing from your wallets???
but you'll learn,
you cant reinvent the wheel brotha!

Also you do know you are slightly increasing the runner lengths of the intake manifold, I would do research as into how this affects power/tuning on a turbo setup.

KleenKrew

You didnt answer my question. As for running a thermal gasket its not for power its for heat created by the cylinder head which in return does create some power.

Hondata have developed a special high temperature insulating gasket which replaces the stock intake gasket. This and bypassing several heat sources significantly reduces the transfer of heat from the head to the intake and incoming air giving you up to 5% more power. Turbocharged cars often use an aluminum intercooler to cool the air compressed by the turbo. The intake manifold is also made of aluminum but because it is heated by the head from combustion and coolant, works in reverse to an intercooler by heating the intake air by as much as 50° C.

Fact: For every 3.3 °C (5° F) rise in intake temperature, air density drops 1%. The hotter the air, the less fuel the computer injects to compensate for reduced oxygen. HondaLogger datalogging software has enabled us to measure intake air temperature under varied driving conditions.

Around town, testing has shown an average drop of around 10 degrees C which is good for around 3 percent power increase. Remember though that 3 percent power increase is difficult to feel. You'd feel a greater change in performance getting rid of that passenger. In certain conditions a 30° C drop has been measured.

The Honda manifold is heated in up to 5 places. From the head, the interior heating takeoff hose, the cold idle valve, the idle control valve and the throttle body heater. The Heatshield gasket kit contains an insulating gasket, and installation instructions. A race version only version with the thermostat bypass blocked is also available.



I answered my own question this morning anyways. The 99-00 civics had an injector air bypass that hondata did not take that into consideration when build their gasket. Therefore the thermal gasket that hondata makes will not work for 99-00 cars with oem intakes.