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Madmax 11-18-2003 02:54 PM

Edelbrock heads
 
Is anybody using the Marine Edelbrock Aluminum Oval port heads on this site? I can't find ANYBODY that has tried/used these. Please give me some real world info on what you think of them if you have. It just seems that they are a smoking deal, yet all i get is blank stares when I ask how they worked.......

I'm comparing them to Merlin oval ports on a mild (under 5100rpm) 454.

Anybody?:crazy:

IRONMAN 11-18-2003 03:25 PM

I have used them on a 454 and a 509 with good results. The ones I used were not the marine version I had to marinize them myself. The 454 had GM rectangle closed chamber heads prior to the Edelbrocks. The gain was about 3 mph even though the compression went down 110cc vs 105cc chambers. I also needed to use more timing advance with the aluminum heads to obtain more power due to the decrease in compression. You will be raising your compression so you may not need to increase the timing. They also had much better fuel economy than the rectangle ports .Good luck, The Ironman

Madmax 11-18-2003 03:42 PM

Thanks for the reply. You might be the only person in the world to have purchased these.......:D

I'm going from the Big block vortec heads (L-29) to these. My compression will actually drop, so i'm hoping they have enough power increase to at least cover that.!

If you went from rectangle ports to these and picked up power, that's promising......:)

Thanks.!

liquid lounge 11-18-2003 04:31 PM

I've got them, the GM version anyway...I did change the 11/32 ex. valve to a 3/8" inconel. I think the Edelbrock marine comes with an inconel exhaust valve[11/32 stem]. I think the 11/32 is fine if your not running alot of spring...don't know if this theory is absolutely true;) . I went from the 325 ports to the 290cc ports, so I did the opposite of what you are doing. I found a noticeable performance increase through the entire rpm range. Some of this was do to the bump in compression, but I think the higher port velocity has more to do with it...just a hunch. I think the port size is about perfect for a 500-525HP motor without too big of cam.
All is not perfect though; the "roval ports" will only match a "roval" intake. Supposedly, this mis-match is not that critical in a dry flow[i.e. port f/i], but if you are running a carb, you need to get the appropriate manifold or match the ports...more$$$.
Always glad to help a CR guy.;)

Nordicflame 11-19-2003 09:08 AM

I've run them for the last 4 years on two applications. The first was a 454 with cam and exhaust upgrades.
The latest was on my naturally aspirated 540 after I had them fully ported and larger valves installed. They reved the 540 easily to 5400 rpm and were torque monsters.
Mine were not the marine version and if you opted to just buy the non coated you could go with the 6049 head which is what I ran. It has 100cc chambers and it will bring your CR on your 454 to just over 9. Great head for your application. If your not in salt the marine version (other then the valves) will not make any difference what so ever. I have no signs of corrosion after 4 years and we have very hard water in these parts.
I just sold them and am having a set of Canfields built by JimV. A better heavier deck for my now blown 540:D

Hope that helps,
Dave

Beak Boater 11-19-2003 08:24 PM

Max...If I am not mistaken they must have been good enough for Mercury Marine, Edelbrock is the aluminum head they use on the 525's. Not sure if it is price or what, made them chose this head. The motor I saw on the engine stand in at the Miami boat show had Edelbrock heads on it. The 540's we built had AFR heads on them. Motor made good torque and horsepower, but the whipples didnt hurt either.

Madmax 11-20-2003 07:17 AM

Thanks for all the replies guys.... Sounds like maybe that aren't such a bad deal after all.!

I wasn't sure about the ones on the 525's.....didn't know if they were rectangular or oval port. Don't exactly have one laying around to tear down and see...:D

Looks like they'll be a good upgrade. If i get them, i'll be sure to let the board know how they work.

Liquid, are you originally from around here? This time of the year makes me wonder why I haven't migrated south.....:crazy:

IRONMAN 11-20-2003 04:46 PM

Nordic Heat, Who did the porting and how much did you gain bu the port job? Thanks, Chris

Pat McPherson 11-20-2003 06:44 PM

Madmax,
Those heads sure sound like a great deal for $1400...

I'll have between 900 and $1000 in my L-29s before I bolt them back on.
Oh well, live and learn. :D

I could not find the intake to match the 290 runner.
Do you have to modify one?

Pat McPherson 11-20-2003 07:15 PM

Hey Madmax,
I got the flow numbers off Edelbrock's web page.
Dyno2000 shows a 40HP increase over the L-29 heads.
Are you making a cam change as well?

IRONMAN 11-20-2003 07:29 PM

I used the Dart O-port intake, It works well and has plenty of room to port match which is what I will do next time it is off. Chris

Madmax 11-21-2003 07:50 AM

Thanks again guys....

Pat, the flow #'s on edelbrock's sight are WAY optimistic. I've seen 2 other benches do them that flowed quite a bit less then what Edelbrock says. So who knows. ??

Yes, I prob would do a cam change. Your choice is really interesting I'll be really curious to see how it works, cause Lunati is a top notch cam grinder. I'm really considering doing a motor change. I'm tired of messing with this one. My thoughts are with a 502/502 shortblock, Edelbrock heads, Crane 731 cam, Edelbrock performer rpm intake, 800 cfm hp500 carb, and my gil exhaust (i get to re-use 1 thing.!!). If I can't swing the bux this winter, i will just put the Edelbrock heads on the 454 and run it 1 more year. It'll be a good OSO tech thread to see how much I pick up over the vortec heads. My friend that has the same boat as me is going to go with Merlin oval heads. It'll be fun to see who picks up more.!

GM makes a CNC matched intake for the heads. It's 229 bucks from a dealer. I think the Edelbrock intake could be made to fit pretty easy, it's got tons of extra aluminum to hog out.

Can't wait to hear how yours turns out. My friend and I have jokingly talked about starting a company that sells a 'package' for these motors. That way we could buy boat parts at discount.!....:D There's alot of interest in them. The '330 on roids' thread shows that.! Keep me in the loop when you get yours done.

Nordicflame 11-21-2003 09:35 AM

porting
 
1 Attachment(s)
Ironman,
I couldn't tell you before and after becuas ethey never touched the motor prior to the port job.
Here's a pic sitting on the 540

Nordicflame 11-21-2003 09:36 AM

1 Attachment(s)
And here they are with a port matched MPI manifold on top of them.....

liquid lounge 11-21-2003 12:16 PM

Max- Yeah, I'm an 'ol CR guy....NE sider...Kennedy '76. Left for college after graduation and never returned. Actually, NE Iowa is one underrated place...IMO. I'm still a Hawkeye nut. Take Care, Berg.

Another plus for the Edelelbock heads is that the 454/502 MAG & the 7.4LX manifolds are already a very close match to the "rovels" and take just a little work for a good match. The runner roof on my manifold was about 3/8" less than the rectangle ports [big] heads! It would really be almost a better match on the LX!! If I were to match these heads to a true oval intake, I would flatten the floor of the intake manifold to match the head and then radius the roof on the head port to match the manifold....but we really need someone more qualified, such as JIMV to chime in.:cool:


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