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Old 03-30-2011 | 09:37 AM
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Usually factory jetting is pretty close on the marine 600 carbs. You might step up a couple of sizes on the primaries. This is mainly due to the fact they tend to run a little lean at the point just before the secondaries open up, which is most likely where you'll cruise a lot. Other than that it's just a crap shoot without an 02 sensor.

Bob

Originally Posted by donzi matt
What would your suggestion for a module be? Either a 20R or V8-HP would allow me to run 10 base and 30 total, but the curves are totally different.

Also, I am still not sure what I should jet the 600 double pumper with to start. Any suggestions would be good, as the motor is in the boat and will not be going on a dyno anytime soon.
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Old 04-03-2011 | 04:59 PM
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Good progress this weekend. Motor is nearly all back together. I need to locate a throttle linkage adapter for the Holley, any ideas what I need? Looks like a Holley 717-7 will work, but seems like a rip off for $34.00.

Things left to do: prime the oil system, install the distributor, hook up the throttle linkage, modify the fuel line to fit the Holley carb, charge the battery, and clean up the bilge and engine compartment.

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Old 04-07-2011 | 04:48 PM
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Well I'll be damned, it runs. Idle is smoother than I thought it would be. You have to listen to hear the cam. I took a quick video, this is with the base timing at 8 degrees. I will set it based off of the advance when it is in the water, I don't like revving it too much on the hose.

http://www.youtube.com/watch?v=Y02ps...er_profilepage
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Old 04-08-2011 | 09:45 AM
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Cool, I'm sure you'll be happy with the performance too.
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Old 04-13-2011 | 03:59 PM
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Nice! Looks like she went back together pretty quickly, too!

I went pretty much the same route with my backup motor (in the boat now)... Vortecs, Performer RPM, Holley carb but I used a GM LT4 "Hot" cam with stock Z06 springs along with the MSD set up that I already had. Runs really well for what it is, and I'm still boating while waiting to have my 383 redone (if I ever get it redone... divorce kinda put a damper on that one). Stock truck short block spinning 5200 max and about 63-64 on GPS.

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Old 04-13-2011 | 04:01 PM
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Did you get your throttle bracket issue straight? I used a Moroso bracket that I got from the local speed shop. It worked with my Morse cable and everything.

Tom
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Old 04-13-2011 | 06:30 PM
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Originally Posted by TomZ
Did you get your throttle bracket issue straight? I used a Moroso bracket that I got from the local speed shop. It worked with my Morse cable and everything.

Tom
Yes, I straightened it out.

I modified the bracket from the Weber carb to fit the Holley stud, then installed a pair of bushings in the carb linkage and the original stud from the Weber. Works perfect. The only other thing I have left to do is rig the overflow line from the fuel pump since the Holley does not have provisions for it. I am thinking of making a piece of tubing in a U shape and threaded through the flame arrester to divert fuel into the primaries. I will flare both sides of the tube so it can't somehow pull through the air cleaner.

About a week away from ice-out here then I will splash it and start prop testing. Hope to get in a good day of cleaning this weekend and install the seats I had redone over the winter. I am hoping this little 22 will be a lot of fun this year.
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Old 04-21-2011 | 05:31 PM
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Took my first run out in the boat after work. The conditions were less than ideal, but so far I am impressed. With the same prop, last year the boat ran a best of 49 mph at 4400. With the same prop, 25 gallons of fuel, and just me in the boat, it runs 56mph at 5000 RPM's. With the old setup, switching the silent choice from closed to open made no difference, now it makes about 150 RPM's difference, how is that for increasing airflow through the motor? I think I would like to try some different props, as the boat feels like it is running pretty wet even trimmed out.

My current intake is a Kodiak marine vortec aluminum intake. It appears to be slightly less of a high rise than my old GM intake was. Would I notice a benefit to switching to an air gap style manifold? Or will the benefit not amount to much?

The only other thing I would like to do down the road is upgrade the exhaust. I am thinking Stainless Marine but would be open to ideas on any other good exhaust systems that will allow me to retain my silent choice.

Thanks again for all of the advice and guidance on this project.
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Old 04-21-2011 | 06:05 PM
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The intake is probably worth 200 RPM. I don't know thT I'd mess with it, though there may be some additional quality in going with a genuine Edlebrock intake.

Exhaust... I went with GLM split runner aluminum manifolds and IMCO stainless risers (I also extended the pipes to the transom tips). This is more than anyone would need on a small block. I have less than a grand in the whole thing.

Boat sounds like she's running great! Good job!
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Old 04-22-2011 | 09:44 PM
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in terms of manifolds, Imco powerflows get the nod for making a little more horsepower... unless you go with true headers.

an airgap rpm is a hard manifold to beat... or a victor jr...
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