Powermizer

Tha is so true. I can't afford 1 engine and drive. Lol. I keep looking at the bigger boats knowing 2 of everything just isn't going to happen, so a 25' is the the best option for power to speed and price. I have seen that to many times. Even with the incomes valves. Had a head of one on a twin 509 setup I built for a friend of mine break just like that. We got lucky on a rebuild, didn't take the bore out. I didn't keep it or take a picture. It was just to sad. Lol

DrLoch

Only valves we had found that worked were inconel exhaust valve and titanium intakes even then we would do a upper after every 2 races and a complete after 4 races. With an upper we would replace valves, springs and rockers (Jesels) When we did the lower end we would magnaflux the rods and crank, replace the pistons.

When we were supported by Mercury racing they took care of all that. They even grenaded one of there rebuilds on the dyno and replaced it. At the race site they would handle everything that had anything to do with the engines, run the valves, check for broken springs/rockers, do the teardowns for the inspectors. We kept the boat at Lake X (Fla) when we weren't racing. They would change engines out and we would fly down do our setup and testing before a race then pack it up and go.

Also, also when they dynoed an engine they didn't do a sweep, they had high dollar absorption dynos and would take it up in stages to the bump box setting and hold it until it settled out. Sort of made ya cringe when they were doing it.

DrLoch

So did you give up on the motor/car and buy a boat now?

Powermizer

Engine up for sale!!

Powermizer

just kidding! I am still waiting for down pipe to be made. i am looking for boat. keep your eyes open for me. I will drive to most anywhere. I want a 250 Eliminator Daytona. fresh water. 2000 or newer.

DrLoch

Will do. I understand the fresh water thing. Will be in FL the rest of this week, will be going to Key West for the SBI race in November as well. I'll ask some of my friends.

hhrfreek

Any more fiddling with your build?

Have a question I'd like to bounce off you guys. So this clutch/flywheel transmits a lot of noise and I think it is causing some false KR. Also see periodic misfires at no load or idle. That never happened before. I've really double checked everything I can think of and narrowed it down to clutch/flywheel.

Do you think the fluid damper could remedy some of this? I know its on the opposite side of the crank, but wondering if it'd deaden vibration that much more than the stock balancer. I don't want to keep taking blind stabs at the issue. Light flywheel is great, but I think I'd go back to stock if I did it again.

On a good note and something for you to look forward to... the ported head and charge pipes really come to life with more boost. The difference between 20 and 24psi is dramatic. On 23-24psi I have logged several 3.4s 60-100mph. That is faster than my car on 24psi last year. Can't wait to really turn it up. I thought sub 3s 60-100 would be a long shot, but its looking very realistic now.

DrLoch

I think John is out boating while the weather is good, don't blame em.

A fluid damper balancer may help.... My bet would be the lightweight flywheel/reduction of inertial mass as well.

Also refresh my old memory. Did you remove the balance shafts on yours?

hhrfreek

I kept my balance shafts. I removed them in my HHR and I did not like the midrange vibrations. The kappa engine mounts are much better at soaking up vibes, but I didn't want to go that route again.

Powermizer

hhrfreek does cylinder #4 have more knock retard than the rest?