Dennis Moore's thoughts on heads

AdamB

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Does anybody have a small-block marine performance book for sale, or at least can tell me what Dennis moore suggests for heads? I have an 1985 Chevy 350 that I want to work a little.

Does he recommend aftermarket, port/polish or???

Thanks
 

FreeBeeTony

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Re: Dennis Moore's thoughts on heads

Don't know what kind of money you want to spend but.........I think the most HP/$ would be to convert to the Vortec heads.

I could be a little partial though................d:)
 

John_S

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Re: Dennis Moore's thoughts on heads

I have the book, but will not sell it. I'd gladly share what it has on head recommedations, but the book is 3 hours away, and won't be able to check it until Labor Day weekend. :'( The good news is that many others that follow the forum have it as well, and you will probably get the answer before I can provide it.

He does provide specific guidance based on what heads you have and on other modifications to engine. I don't remember the specific guidance for your year heads. In general, he recommended cleaning up the ports on most heads. He also recommended going to larger valves. I wouldn't go there unless you are building the rest of the motor to hit higher rpms above 5K, and have a much freer flowing exhaust.

I do remember Dennis liked the '87-'96 head better, because of the relocated spark plug and he considered the '96-above vortec head to be the best production engine head available. Going to either of these heads, requires a new intake manifold. The '87-'95 has canted center bolts, and the vortec has taller runners and no center bolts.

If you have flat-top pistons (w/valve reliefs) vortec heads will put you up in the 10:1 compression range. Might not be an issue for you, but expect to be buying premium gas only. If you have the dished (smog) pistons, then the compression is about 9.5:1, which is the same as current marine 350s. Also given its an '85, probably not worth it unless the rest of the bottom end is fresh. Also make sure your drive condition will be up to the added hp. Before going vortec also make sure it will work with your cam, which I believe is standard hydraulic lifter, not roller.
 

AdamB

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Re: Dennis Moore's thoughts on heads

the alpha one is freshened up, and I changed over to mpfi which utilizes a Holley intake which has the center bolt pattern for both angle of bolts.

I thought about the vortecs, but also was thinking about an after market iron head like world product dart heads that will flow even better then the vortecs and I wouldn't have to change anything else.

For the price of a street/strip port/polish and valve job on my heads, I could probably get aftermarket heads that'll be better.

Was just curious what Dennis Moore thought. I would buy the book if I could find it anywhere.
 

John_S

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Re: Dennis Moore's thoughts on heads

Adam, Dennis does talk about aftermarket cast-iron heads in the book. I believe he does talk about the world product heads. Also, other GM cast-iron heads that can be purchased, but didn't come in any production marine engine.

As far as modifying fuel injection or adding after-market FI, he does not cover that.

PS: I did a quick check around the house just in case it didn't make it to my container of boat manuals. Its not here :'(
 

AdamB

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Re: Dennis Moore's thoughts on heads

Thanks, it'll be a late fall project. I want to pull my heads anyway to get them checked, and if I can find a cheap pair of aftermarket heads that'll work with my set up that is how I'll probably do it.

Still, I'd like to buy a copy of the book, even a photo copy 8)
 

AdamB

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Re: Dennis Moore's thoughts on heads

That link doesn't work for me, but you can email them to me at adamborz@aol.com. Thanks.
 

FreeBeeTony

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Re: Dennis Moore's thoughts on heads

Will have to wait until I get home tonight.
 

FreeBeeTony

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Re: Dennis Moore's thoughts on heads

Having trouble emailing you..........

And the PM's aren't working either.......I don't think.
 

AdamB

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Re: Dennis Moore's thoughts on heads

I emailed you back.
 

AdamB

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Re: Dennis Moore's thoughts on heads

thanks, you're the man!
 

AdamB

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Re: Dennis Moore's thoughts on heads

Do these 4 pages cover it all, or does he mention after market iron heads?
 

180shabah

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Re: Dennis Moore's thoughts on heads

I have to agree with FreeBee's first post, the Vortec heads are hands down the best value out there. The flow as well as(and in some cases, better than) many aftermarket heads. If you need even more performance, you can get them on the used market set up any way you like(port polish, 3 angle valve job, larger valves, single or double springs....) and still save a handful of cash.
On a standard Merc 350(260hp) the change to Vortec heads(with no modifications to them) will put you well over 300hp.
I had planned on doing the conversion on my boat, but we have decided to get a larger boat.
Good luck.
 

Bondo

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Re: Dennis Moore's thoughts on heads

I have to agree with FreeBee's first post, the Vortec heads are hands down the best value out there.
Ayuh.................

And I'll add,..........
Anymore than the Standard Production Vortec Heads are a Waste of Money,.......
Unless you're willing to throw the Money for a set of True Headers,+ an Open Exhaust.........

Btw,..... Old School thoughts on Allowable Compression Ratios go Out the Door with the Vortec Chambers,.....
10:1 is Not unheard of..... Without Denonation.....
 

FreeBeeTony

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Re: Dennis Moore's thoughts on heads

When I go to WOT..............it sounds like a damn speed boat! It's gotta be 300+ HP......pushing this Grady past 35MPH........
 

AdamB

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Re: Dennis Moore's thoughts on heads

Update. I purchased new Dart iron eagle heads with heart chambered combustion chambers (like the vortec). The seller said will up my compression about 1/2 point and should add approx 30 hp.

My intake manifold and my valve covers will fit right up. Plus, I'll have new heads, not some 20+ year old ones that were rebuilt who knows how many times. When I changed my intake manifold out earlier in the year, I couldn't believe all the build up in the coolant passages of my heads. Was gonna take mine to the machine shop for refit, but decided to go with new ones with larger 2.02/1.6 stainless valves. factory hardened seats etc. BTW, Dennis Moore recommended 2.02/1.6 valves, that's why I went that route.
 

Bondo

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Re: Dennis Moore's thoughts on heads

I see a major Disappointment in your future.............

As stated in your Other thread,............
Stock Vortec heads would be a Better Choice........
 
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