Been long time reader but new to the site, I picked up a 76 Tahiti super tiger last year, the previous owner said it would run over 80 @ 6K on GPS.
I've taken it out a few times and have blown both bowl and nozzle gaskets out and have reversion problems with water in the exhaust when I try to run water thru the headers. (it runs great dry but cooks the sides of the boat and melted the carpet!)

The engine is a 514 (4.44 bore with 4.14 stroke) 10.5:1 compression with large valve 2.25 / 1.97 bowl blended & ported Dove "C" heads. the cam is a Erson JB300 but I don't know what the spec's.

I'm guessing it has a "B" impeller but will find out when I pull the pump apart.

Anybody have spec's for the cam and will the water restrictors that mount in the header -8 line help me with the reversion problem. I'm hoping to just allow enough water to get a LITTLE steam thru the headers until I can set it up with Lightning or other double wall versions. Look forward to your insight and help.

Thanks LakesOnly
I'm also running an Offenhauser turbo thrust tunnel ram with two 6109 750 double pumpers. I did leave a inquiry with PBM a few day ago...I also found the '99 Erson catalog on line however it listed JB100 & JB200 with 108 LSA maybe the JB300 was a later grind or my reciepts are wrong? Erson#260281 JB300.
I have the basset headers although they're chevy headers mounted on aluminum adaptors and the exhaust ports had some type of insert with a "tongue" going up into the port.
The ports have been worked alot ~ I've run it with and without them and can't really tell if there's difference. I've only driven it about 1 hr so far.

In regards to the header plumbing I have a functional "t" valve and have cleaned / replaced the water lines. I'm running two 5/8" lines of the thermostat housing, one to header "t" fitting and the other to a dump line with a gate valve. The gate valve is wide open and I have the other gate valve off the jet pump set to maintain 160. degrees.

Last time out it would begin to mist the headers at 2400 rpm and when I stood on it I had pretty large streams of water pouring out between 5000 -6000 Rpm and then it started missing ~ stopped the boat and no water at idle. I'm thinking the restrictor jets for the -8 lines should really limit the volume and help me?

if I can get this water issue resolved I'd like to pick up some Ford headers and eliminate the adaptors. If not I'm thinking a larger solid roller something in the .255 /.265 @ 50 with .720 lift and ceramic coat the headers and forget the water!

Not real sure what rods are in this other than 6.8 length so I don't know if I should twist it anymore than 6K.