manifold gasket

[datdrift]

i finally got around to doing my head to manifold gaskets yesterday, it went well with no helicoils needed it dident seal straight away, but after it warmed up a bit it was fine, its the first time ive driven it with my big bore without it blowing, and its sounding sweet but im only running around 7psi cos of my fueling problem, which allows me to rev to about 5.5rpm before it starts poping.....
all was going well until i needed some fuel and wasent near a shell garage, so i put £10 of esso 97ron supreme in, with probably £10 worth of optimax left in the bottom of the tank, and now it would only rev to 4.5rpm so im gonna use that up and go back to optimax......im getting a fse fuel reg soon so maybe that will help a bit?

[PukkaSilvia]

It sounds like a problem with the fuel pressure regulator and/or your timing