Those gaskets will not work if the port is more than 165cc stock type heads. Aftermarket SBC heads usually take 1205 or 1206 gaskets for the larger runners.
Sportsman 2 heads have the heat riser port, but It is typically blocked of at the bowl area. One needs to drill to connect the two.
Thanks for the help. I never knew the crossover was blocked from the inside. I've owned these heads for over twenty years and never really thought about the crossover until recently with this new gas percolation thing going on. I suppose the gas just has more alcohol in it in recent years. Plus I guess I've been using the wrong stock manifold gaskets this whole time. It wasn't until recently that they failed. Guess I was just lucky prior to this last set. So anyways, I got the Fel Pro 1205 gasket and I'm about to put it on. I really appreciate everyone's help.
Would you guys use a permatex on the water ports? If so which one? I think a long time ago I used to use the ultra blue. But this last time around two years ago I used ultra grey and it failed. But the bolts also were a little loose. Maybe they vibrated loose or something.
around coolant ports: permatex #2 non-hardening pn 80016 it's neither RTV or Silicon put a dab on clean bolts as well
I use the right stuff around the water ports sparingly. I also use a tall bead of the right stuff on the ends, and toss the end gaskets in the garbage. There is also a torque sequence that starts from the center. I'll go around about 4 times.
That's exactly what I did yesterday 1320feet. Went with the right stuff and chucked the end rails. I'll find out tonight when I fire it up if it all worked. Thanks for all the help.
The right stuff ain't always the the right stuff ... it seals Very well but can be Very difficult to separate pan / timing cover / intake that was installed with THR, then cured.
I used the fel-pro 1205 and the cross over blew threw the gasket into the heat channel of the intake. I have my intake off now and would prefer to stop this from happening again. This is with Holley 300-36 intake and AFR 195 heads. Seems like I remember back in the day some intake gasket sets came with tabs you would cover the holes in the head to block it off. Factory heads had the square opening but the AFRs have a ~5\16" hole there.