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Quote:

Originally Posted by Raylar (Post 3409751)

Uncle Dave:

Those are excellent numbers and results from a 406 small block!
If this boater can get at or close to those numbers from his small block using your specs and examples, he will be a very happy camper!
Learn and profit from someone else's excellent design and results and you will be way ahead, don't re-invent the wheel!

Best Regards,
Ray @ Raylar

Thanks Ray.

I have to give the credit for the combo to the engine builder. An old drag racing guy named Dick Gazan thats been doing it since I was forming eyelids.

Your LSM 550 is an awesome package I would love to have the money to buy!

UD

Quote:

Originally Posted by HaxbySpeed (Post 3409957)

No it was great down low and idles strong. That dyno didn't have enough water supply for long pulls. The 406 is a great combo the 434 works good too. I like small blocks :coolcowboy:

Wow thats a nasty piece for sure! Big fun.

Im guessing it needs race gas and is setup for car though.

I asked my builder about a 430+ setup and he told me they make great power but have issues with wear which I thought was strange, but recited stuff about getting there with stroke causing rod angle issues.

I was originally interested in 454 SB short block with my heads, but stuck with my old "garage special" 406.

UD

Quote:

Originally Posted by Uncle Dave (Post 3409414)

Lets back up a bit.

What kind of drive system in a "stinger 202"?

How much does it weigh? If you get past 70-75 with a heavy boat it want to run anymore without hydraulic steering - have you provisioned for that?

What kind of HP and torque are you expecting to get at what RPM range. what kind of exhaust are you going to be running - the factory stuff will flatten your engine and choke it so you will need a good aftermarket exhaust.

Aluminum vs Iron heads will either save you possible detonation if you get a tank of lousy gas (always a possibility with a boat) r let you run more static compression to begin with.

If you have the short block apart you might as well build in some bigger cubes.

I have much experience with small blocks and boats.

Uncle Dave

The boat is quite a project.. and I am taking it one step at a time. from the inside, out

Im not sure what the boat weighs... but I towed it home at 80 mph behind a 4cyl toyota tacoma.. And it was lifting off the trailer. So, lets just call it light...

I will be dealing with the drive system later, it had through hull exhaust and I will be looking for higher flowing manifolds later on in the project.

I have a displacement limit on my lake at 360Cu in..

Id rather pay a little extra and get an all new head than deal with digging parts out of boneyards that have been well used up and need a lot of work done to them.

So let's limit this to aftermarket Iron heads.. 165's might be a tad small and 230's are probably too big. Am I wrong on this?

Quote:

Originally Posted by Uncle Dave (Post 3410583)

Nope, pump gas hydraulic roller. Going on it's fourth season now. The 454 small block isn't a great combo but if you do the
434 right it's no problem. For forced induction I like the 406 better.

Quote:

Originally Posted by zerotact (Post 3411112)

I think you are right. 165's will be too small - and 230 too big.

I wouldnt expect any real gains until you do the exhaust manifolds with a quality aftermarket unit - so Id try to save up and time it so they both get done.

( SB marine exhaust is one of the harder components to find used)

I ask about the drive because Im suspecting its an i/o which means the unit needs to idle at around 800 RPM which means no big cams/ head ports or runners.

UD