350 merc. Intake manifold gone, not sure where to start...

[jonoman69]

I have a 97 crownline 210 ccr. It has a 350 merc with a 2 bbl stock setup on it. At startup this year I noticed my intake was bubbling through, must have rusted through from the inside. So while trying to find a new intake to put on it. I found out that the heads on it are swirl port heads instead of the vortec heads that are suppose to be on it. Of what I read these arnt very good heads to have. So my question is where do I start... Should I put different good used heads on, intake and maybe a 4 bbl carb. Or do I just put a new intake and get a 4bbl carb on it and haul it out in the fall and see what I actually have for a motor and freshen it up. I have no way of finding out what else the previous owners done while changing the heads, liek maybe cam or why they were changed. The boat is no powerhouse, pretty slow out of the hole and no top end. I'm assuming when it had the vortec heads from stock it would have been a bit more powerful.

 

[Bondo]

Re: 350 merc. Intake manifold gone, not sure where to start...

I have a 97 crownline 210 ccr. It has a 350 merc with a 2 bbl stock setup on it. At startup this year I noticed my intake was bubbling through, must have rusted through from the inside. So while trying to find a new intake to put on it. I found out that the heads on it are swirl port heads instead of the vortec heads that are suppose to be on it. Of what I read these arnt very good heads to have. So my question is where do I start... Should I put different good used heads on, intake and maybe a 4 bbl carb. Or do I just put a new intake and get a 4bbl carb on it and haul it out in the fall and see what I actually have for a motor and freshen it up. I have no way of finding out what else the previous owners done while changing the heads, liek maybe cam or why they were changed. The boat is no powerhouse, pretty slow out of the hole and no top end. I'm assuming when it had the vortec heads from stock it would have been a bit more powerful.

Ayuh,.... While the earlier heads don't flow, 'n make Power like the Vortecs,...
They both suffer from bein' Lighter castin's that crack or rot out sooner...

There's an honest 20 horsepower increase from the Vortecs,...
So, I'd probably go that route, Now, rather than later, myself...

Of the Vortecs, last I checked there's 2 castin' numbers available, the 662s, 'n the 906s...
The 906s Usually have bigger, stronger exhaust valve seats...
For the same reasons the Hot Rodder's don't care for the 906s, they're Perfect for a Boat motor...

 

[jonoman69]

Re: 350 merc. Intake manifold gone, not sure where to start...

Unfortunately I don't have the 2 grand it would cost me to put vortec heads and intake and carb on. Not to mention I don't know if the cam was messed with. Would it be worth while me putting a 4 barrel intake and carb on those heads or am I just wasting my time. It wasn't to bad last year with the 2 barrel. Bit pokey gettin out of the water and top end is only 40 miles but it is a heavy boat to.

 

[jonoman69]

5.7 what to use for carb??

5.7 what to use for carb??

My intake just went on my 350 in my 97 crownline. I'm currently running a 2 barrel stock carb. Since I have to replace the intake should I go with a 4 bbl carb to? Also my heads are swirl port heads which shouldn't be on the motor anyhow, defiantly not helping the lack of power the motor has for the size of boat.

 

[achris]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

Using it in saltwater, get an iron manifold and an Edelbrock 1409 carb. In freshwater you can use a dual plane ali manifold, with a 1409 carb...

 

[jonoman69]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

Is it worth putting a 4 barrel on with those heads, they are swirl port heads.

 

[achris]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

I have no idea what a swirl port head is.... Sorry...

EDIT: Just did some reading up on these heads. Doesn't sound very good, but remember you're not revving your engine beyond about 4800... At that speed I don't see there being much difference... Might be worth finding some different heads???.

 

[Bondo]

Re: 350 merc. Intake manifold gone, not sure where to start...

Unfortunately I don't have the 2 grand it would cost me to put vortec heads and intake and carb on. Not to mention I don't know if the cam was messed with. Would it be worth while me putting a 4 barrel intake and carb on those heads or am I just wasting my time. It wasn't to bad last year with the 2 barrel. Bit pokey gettin out of the water and top end is only 40 miles but it is a heavy boat to.

Ayuh,... The 4 barrel carb, 'n matchin' manifold is Still good for 'bout 20 hp,....

Add in the Vortec heads, you'd be talkin' 'bout 40 hp....

 

[achris]

Re: 350 merc. Intake manifold gone, not sure where to start...

Errrr, this is duplicate thread.....

Already asked in this thread -> /5-7-what-use-carb

 

[Bondo]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

Is it worth putting a 4 barrel on with those heads, they are swirl port heads.

Ayuh,... Those aren't Vortec heads, but they were the Best Chevy built durin' the '80s, 'n '90s, til '96 when the Vortecs came out...

They Not that bad, just not as heavy as the previous Chevy heads...

 

[steves86ta]

Re: 350 merc. Intake manifold gone, not sure where to start...

Unfortunately I don't have the 2 grand it would cost me to put vortec heads and intake and carb on. Not to mention I don't know if the cam was messed with. Would it be worth while me putting a 4 barrel intake and carb on those heads or am I just wasting my time. It wasn't to bad last year with the 2 barrel. Bit pokey gettin out of the water and top end is only 40 miles but it is a heavy boat to.

I just went through all of the research on this subject myself (for a 350 im building)

Here is what i have found and it will be nowhere near 2K

you can pick up a set of Summit Racing Vortec heads here: http://www.summitracing.com/parts/sum-151124/overview/ they are 310 each. These are completely built and good to .520" lift. (if i could do it again i would have gone this route instead of rebuilding stock GM heads)

You also have the option of ordering some vortecs from SDPC in their "Upgraded Vortec kit", this will come with everything you need but you will need different head gaskets
https://sdparts.com/details/scoggin-dickey-parts-center/sd8060arpm

These are the head gaskets i bought:
http://www.summitracing.com/parts/fel-17030

The Edelbrock intake is EDL-2116 for a performer intake.

this will be a solid 40+ gain for your stock engine, all you will need is a 4 barrel carb

 

[jonoman69]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

"Ayuh,... Those aren't Vortec heads, but they were the Best Chevy built durin' the '80s, 'n '90s, til '96 when the Vortecs came out..."

All the research I've done is that they were never put on marine engines stock for the reason that they were horrible heads and didn't put out any hp out. Am I wrong ??? Will a 4 bbl make enough dofference for me to notice or be worth spending the money on it, with those heads ??

 

[bonzoscott]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

My guess is you will notice the difference in your fuel bill.
Edit - I take that back. The four barrel Quadrajet has smaller primaries than your two barrel. So If you stay outta the secondaries, will be less fuel consumption. 6 Of one, 1/2 dozen of the other...

 

[jonoman69]

Re: 5.7 what to use for carb??

Re: 5.7 what to use for carb??

My guess is you will notice the difference in your fuel bill.

Anymore opinions on that. I've had quite a few people tell me that if you drive it normal and not always opening it up the fuel if anything should be less. And that a 4 barrel is more efficient until you open up the secondaries??

 

[Bondo]

Re: 350 merc. Intake manifold gone, not sure where to start...

Errrr, this is duplicate thread.....

Already asked in this thread -> /5-7-what-use-carb

Ayuh,... Good catch,... Merged....

 

[PowerAddict]

Re: 350 merc. Intake manifold gone, not sure where to start...

Ayuh,... Good catch,... Merged....

ha, you merged when I was posting and caused me tons of confusion! haha

my original response was:

I think the general concensus will be not to bother with the 4 barrel, especially with not-so-great heads, log manifolds, who knows what cam, etc.

Calulating your peak Air-flow for your set up, with the aforementioned hardware, I assumed a volumetric efficiency of 80%, and I even gave some room and made your peak RPM 6000 (even though you'll probably never see it). You're still only at 486 CFM.

Now, if it were me....I'd probably still do it, because I don't like doing things twice...but because of that very same point...I'd wind up doing heads and cam too....and wind up spending all summer working on it.

So moral of the story....just put an intake on it, and enjoy boating this summer. my .02

However, since you brought up the doing the heads. Thats exactly what I would do, but instead of buying new ones. I'd go to the junkyard and find a 96+ pick up and pull them off of for dirt cheap...THEN I would add a nice al intake (with bronze inserts if salt water) and a 4 bbl.

 

[Dawg'sLife93]

Re: 350 merc. Intake manifold gone, not sure where to start...

However, since you brought up the doing the heads. Thats exactly what I would do, but instead of buying new ones. I'd go to the junkyard and find a 96+ pick up and pull them off of for dirt cheap...THEN I would add a nice al intake (with bronze inserts if salt water) and a 4 bbl.

I don't know much about boats, but I know chevys. IMHO, I wouldn't do the junkyard thing. You buy a set of junkyard heads and by the time you have them rebuilt, checked for cracks(Which Vortecs are prone to do), and everything else you need to do to have a nice long trouble free run life, you'll be at 6-700 dollars anyway. I would (and have bought) the summit heads. As for the vortec heads, the 062s is what everyone wants, they are not as prone to cracking as the 906 heads, if you do find a good set of not cracked 906s,they with serve you well. The main problem with the Vortec truck engine is the intake gaskets like to blow and overheat the engines, that causes alot of the cracked heads.

Like Steve86TA said, grab a Edel 2116 or even the summit 226018(Edel knock off) for 143.00, then add the 1409 Edel carb and a summit 1102 cam kits, you should come in under 1500.00 max. If you can't swing that budget, just sorce a used stock intake and fix what you have until you can get the cash for everything at once. You'll spend a lot more throw a few piece at it, at a time.

As for the swirl polished L05 350 heads, thats all that was offered factory from 87-95, I'm sure they were used on boat engines. I've seen a lot of center bolt heads on 90-94 boats.

 

[jonoman69]

Re: 350 merc. Intake manifold gone, not sure where to start...

So would it make sense for me to put an old intake on it which I have access to and buy a 4bbl carb. The intake I have access to is a 4 bbl intake. Or should I just try to find a 2 bbl intake and not waste my money on a carb?

 

[achris]

Re: 350 merc. Intake manifold gone, not sure where to start...

So would it make sense for me to put an old intake on it which I have access to and buy a 4bbl carb. The intake I have access to is a 4 bbl intake. Or should I just try to find a 2 bbl intake and not waste my money on a carb?

If you plan on keeping the boat, and at some stage in the future changing the heads, then getting the 4 bbl carb now would make sense... If, however, either of those statements is false, then no, stick with the 2 bbl....