Can't find THE answer, Rotary Valve 720
- Thread starter Sebastian Bluecrew
- Start date
- Status
JeremyD615
Well-Known Member
Be sure to really watch your plugs for any lean conditions with those carb kits. SBT does sell Mikuni kits, but the SBT branded ones are aftermarket, and can cause problems...
Sebastian Bluecrew
Member
Well so far it is running a little more rich than i want it but trying my hardest to NOT detonate pistons like everyone else who had a factory pipe. So far no issues, and I held it wide open for over a minute to see just what would happen. Here is a video when I was running it yesterday.
If your HS needles are out 1 turn then you can turn them in to closed for some more rpm. 1/4 open on the back one maybe just in case you have an early chamber with the 34mm stinger opening. Looks like it is a ton of fun as it is though.
JeremyD615
Well-Known Member
It looks pretty solid to me! I’m glad you’ve got it up and going strong...
Sebastian Bluecrew
Member
I called Factory pipe and asked them about that stinger size, they claim someone made that rumor and in no form is there a difference in size and told me to ignore it... However, they did tell me this is one of the very first, being that my solenoid is tapped directly into the header.. But thats just what they said.... I ignored the stinger size... and right now I dont need more rpm as i cant keep it in the water and its cavitating.. a work in progress..
Glad you have worked it into a good spot.
Whoever answered at FPP is clueless and that is a shame. They used to swap out the original 34mm chambers for the newer 38mm ones. I have an old one here that I got stuck with but I could always hire a welder to fix it. There is no way to push an engine and not overheat the rear piston with the early ones. I went through this personally with them back in the day. Luckily it's a problem you obviously don't have if you held it WOT for a minute.
Whoever answered at FPP is clueless and that is a shame. They used to swap out the original 34mm chambers for the newer 38mm ones. I have an old one here that I got stuck with but I could always hire a welder to fix it. There is no way to push an engine and not overheat the rear piston with the early ones. I went through this personally with them back in the day. Luckily it's a problem you obviously don't have if you held it WOT for a minute.
Sebastian Bluecrew
Member
It was a lday, she seems to answer every time.. Curious, you got any more pipes to sell? Something that would fit on a 587 or 657?
noviceskier
Active Member
What impeller are you planning on getting for it?
Sebastian Bluecrew
Member
well i was advised by Impros that this impeller is very tall, it should take thousands of dollars on a build to push this impeller.. But It has no strugle with me, so his suggestion is I have a problem, and I am not using even half of this impeller.. I should not be going up in pitch, but correcting the problem, then when it is struggling to push this prop, I can have it lowered in pitch to something like a 15/23
- Status
