When I did the HG's last spring I port matched the intake side of the heads making them all the same size and opened them up enough to have the "entrance" into the heads larger than the end of the passageway before the bowl, so creating a "funnel" down to the valves which promote acceleration of the air mass into the cylinder (in theory of course ).
On the exhaust side all I did was smooth it up a bit, and took the ridge off the exit side of the valve sleeve (its the darnest thing I've ever seen with that ridge right around there) and thats it... no gasket matching the head to manifold or anything. The exhaust manifolds I opened up at the exit getting rid of the ridge there and got it opened to almost 2".
Nothing done to the cumbustion chamber except cleaning and smoothing.
Here's what I've notice all summer........ the car blasts away like a bat outta hell like its never done before, and she'll even light up the tires on drive pavement doing 30mph and flooring it..... there's no mods like od pullies etc, and the exhaust is stock except no resonator, and the air silencer is removed.
When I plant the right foot from a stand still (barely chirps the tires new Michelin Hydro Edges), the boost gauge hits 8psi right away, then climbs up with RPM's hitting 11 psi as the rpm's go through 5000. The car seems to lag a little when its below 1800 RPM's but really starts pulling at 2100 and just keeps on pulling harder and harder blasting through 5000.
Now don't get me wrong as I'm not complaining the way its running, but only hitting 8 psi then climbs as the RPM's go up... is that normal? I don't think I have vacuum/boost leaks as I've done the tests on this site for such and everything passed beautifully.
Before the HG's went, I'd floor it, and it would nail 11 psi right off the bat, and stay there till about 4500 RPM's then start dropping off a little. Now I do know when things are opened up boost will drop, and you can OD the blower.... but THAT much????
Anyways, I'm thinking of getting a 5% Jackshaft pully but I'm hesitant..... it just seems a little wierd the way its behaving right now... and my wife would kill me if I killed the car .
Frit
On the exhaust side all I did was smooth it up a bit, and took the ridge off the exit side of the valve sleeve (its the darnest thing I've ever seen with that ridge right around there) and thats it... no gasket matching the head to manifold or anything. The exhaust manifolds I opened up at the exit getting rid of the ridge there and got it opened to almost 2".
Nothing done to the cumbustion chamber except cleaning and smoothing.
Here's what I've notice all summer........ the car blasts away like a bat outta hell like its never done before, and she'll even light up the tires on drive pavement doing 30mph and flooring it..... there's no mods like od pullies etc, and the exhaust is stock except no resonator, and the air silencer is removed.
When I plant the right foot from a stand still (barely chirps the tires new Michelin Hydro Edges), the boost gauge hits 8psi right away, then climbs up with RPM's hitting 11 psi as the rpm's go through 5000. The car seems to lag a little when its below 1800 RPM's but really starts pulling at 2100 and just keeps on pulling harder and harder blasting through 5000.
Now don't get me wrong as I'm not complaining the way its running, but only hitting 8 psi then climbs as the RPM's go up... is that normal? I don't think I have vacuum/boost leaks as I've done the tests on this site for such and everything passed beautifully.
Before the HG's went, I'd floor it, and it would nail 11 psi right off the bat, and stay there till about 4500 RPM's then start dropping off a little. Now I do know when things are opened up boost will drop, and you can OD the blower.... but THAT much????
Anyways, I'm thinking of getting a 5% Jackshaft pully but I'm hesitant..... it just seems a little wierd the way its behaving right now... and my wife would kill me if I killed the car .
Frit
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