leaking gas from cyl 3-4 with stock manifold and Header

[davidkontra]

has anyone had problems leaking gas from cyl 3-4 with stock manifold and Header? The felpro gasket with the metal tabs for the ports is the gasket Im using. Is there a better one?

[baz]

sounds like you have an uneven pinch between the inlet and exhaust flanges
if the inlet is smaller then it will not tighten properly and you get a small leak

[BQS4]

Someone, somewhere wrote a good way to stop leaks on header gaskets and it seems to hold true. the tip was to soak the gasket in water and install it wet. When it dried, it would conform to all the irregularities of the header flange.
JMTCW,
Gene

[davidkontra]

do the peopel with headers use the metal tabbed gasket? or paper only?

[GTJIM]

I see you list stock (intake?) manifold and header.
The usual problem is that the header flange is made from "inch" thickness steel and is a different thickness to the machined areas on the stock intake where the washers contact. This is 12mm thick, on stock manifils, and often header flanges are only 3/8" thick. This makes a 'step' there that means the header flange is not properly clamped. So check that the thickness is the same. Add weld-on half-washers if necessary to get both bits the same thickness where the washers under the manifold bolts clamp.

[davidkontra]

Im not leaking from the header though. I solved that problem of the thickness with washers that clap on the intake and exhaust that were oversized to fix that. My concern is my intake flooded with gasthat pooled then. and washed out on the intake side. from what you said, it would be that the header isnt tight, but the manifold would be.

[RallyBob]

Im not leaking from the header though.

Then the header is probably thicker than the intake manifold. Tighten the bolts and the header is snug, but the intake is not. Not uncommon on aftermarket headers at all, most of them are incorrect. This is why I went through so much trouble two summers ago to weld up my flanges to the proper thickness.

BTW, did you ever try getting the EFI manifold I sent you together?

Bob

[davidkontra]

yeah i have the manifold together, and the megasquirt is in as well. I have not installed them yet though. I did not weld the bungs for the fuel injectors, instead i am using the plastic plates. I have the TP sesnor, o2 sensor, and map sensor. Intake temp sensor did not spike when the megasquirt tried to find it.

I need the timing in order first before the FI goes on though, so i have to use the carb in the meantime, ANy suggestions?