sounds like dist locked already, 40 is to much in a boat

I agree. 35 even sounds aggressive for a 10.25/1 static comp ratio.

Should idle great. With that much timing at idle. ? Isn't that why you lock them out. To calm big cammed motors. I'm confussed here

We weren't told about the cams.

If there is a decent cam, then those carbs are even more out of their league.

Cap the breather line coming off back of carburetor. The valve cover breather should be an open elbow both sides connected to the flame arrestor. If idle still to high back down secondary adjustment to lower idle speed. See if it will take a load and not stall after that.

Unfortunately, I don't know much abt the hyd/roller cams installed. Prev owner did say the entire valve train is Crower but he couldn't recall the cam specs.
It's nothing wild. No lope and has strong vac @ idle.

Adj'ed the timing on both engs to 34 degs.
It didn't have much of an effect on the idle quality, but makes me feel better.

I re-adjusted the secondaries some more. Wound up with the secondary transfer ports almost disappearing and now have a pretty solid idle at 775 RPMs on both engs (with normal idle speed screw backed off completely). Then adj'ed idle up to 800-825 rpm with normal idle speed screw. Both engs seem happier now. Thx for suggesting that SB!

The PCV issue still needs to be addressed. I kind of like the idea of having a PCV sys to evacuate the corrosive blow-by gasses. I'm planning on replacing the "extra" PCV valve with an elbow (hose going to flame arrestor/air filter) and hopefully will still have a solid idle in gear. If not, I'll plug off the vac port used for PCV and have both valve covers vent to the flame arrestor.

After adj'ing the starboard eng timing, I noticed it didn't seem to adv with rpm like it did before.
Wanted to pull the dist caps and see what's up with the mechanical adv mechanism but ran out of time.


It will be next week before I can lake test, but I'll let ya'll know how it turns out.

without a wideband or plug check how do you know its too much fuel and not not enough? normally a high idle after revving is LEAN, when richer they drop back easier to idle, is timing locked out? if so its easier to idle but hard on starters, what is timing at idle? I would turn mixture screws all the way in and start at 3/4 to 1 full turn out, that's normally right on the money, if carbs are old you can also have issues with things sealing like the body and flange allowing issues, many guys tighten the carbs too much and warp them...

I suggest a wideband for tuning, I cannot stress it enough it is by far the best tool I added to my boat to keep things checked out and rule out issues, without your just guyessing a lot...

if you are running a msd dist. take the cap off and check for rust !

I agree that WB02 is the way to go. I've had one installed in my street ride since the days you had to build the p/s and controller yourself then convert the 0-5v output to AFR in your head. Putting one on the boat is definitely on my short list.

These 4010's are not your normal looking Holleys.There's no float bowls and metering blocks hanging of each end which is where most over tightening issues occur with the traditional Holley carbs.

Yeah, I've heard a few stories abt that. I'll check them this weekend.