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formula31 10-28-2005 05:32 PM

Re: Head advice on BBC
 
http://www.flatlanderracing.com/
$1349

ratman 10-28-2005 05:54 PM

Re: Head advice on BBC
 
JEFF, the heads are on the cover of the summit catalog i got in the mail about a week ago. give them a call, ratman

hondatv 10-28-2005 07:13 PM

Re: Head advice on BBC
 

Originally Posted by amer3
cp has them for 1500. just need springs 880 6155 rec Edelbrock i have flow chart on them. had my flow when i got them.i can email it to you.


http://www.cpperformance.com/detail.aspx?ID=4094

amer3 : can I get a copy of the flow chart? I'm thinking about buying a set for my 540.

IRONMAN 10-29-2005 07:52 PM

Re: Head advice on BBC
 
I have used the edelbrocks on 454's and 509's with good results. On the 454 I had changed from rectangle port closed chambers 105cc to the edelbrocks at 110 cc's so I lowered the cr and still picked up about 200rpm's but I had to increase the timing to 40 with the flattops to get the power due to the change to aluminum heads and 8.9 cr.

jeffswav 10-30-2005 06:54 PM

Re: Head advice on BBC
 

Originally Posted by Pat McPherson
Probably 20-30HP. Not really worth the time and $$.
If you cut the heads to install hardened seats for larger valves, the bowls will likely need to be ported again.

Hey Jeff,
How did you get to 8.5:1 with flat tops? Did you deck the block and mill the heads?

Also are you sure your intake won't seal against rectangular port heads? Some oval port intakes do...

I have a stroker kit, the extra displacement give a higher compression ratio.
I called Holley and the ports could not be ported on my oval port EFI intake to match the Rec ports.
Thanks,
Jeff

ratman 10-30-2005 07:05 PM

Re: Head advice on BBC
 
if you weld them up you can probably port them to match. back in the day when the were racing 900cc z1 kawasakis they welded up the intake port to go from a stock 28mm carb to 44mm carbs, there was no material left from the original port after all was said and done cuz the new ports were huge. id lay a gasket from a rect port on the intake and see how much you would have to build it up with alum welding before port matching it! if there a will there's a way. merc doesn't look at it that way, nescessity is the mother of invention

jeffswav 10-30-2005 07:18 PM

Re: Head advice on BBC
 
Thanks for all the great input.
It sounds as though the edelbrock marine ovals are the best bet. If I add them to my setup how much HP, RPMs, and Speed do you guys think this would add to boat?
I have a Bravo 1, 1.5 drive, 25 pitch Lab finished Mirage running 4600 RPM 66 MPH GPS.
Thanks,
Jeff

Pat McPherson 10-31-2005 09:53 AM

Re: Head advice on BBC
 

Originally Posted by jeffswav
Thanks for all the great input.
It sounds as though the edelbrock marine ovals are the best bet. If I add them to my setup how much HP, RPMs, and Speed do you guys think this would add to boat?
I have a Bravo 1, 1.5 drive, 25 pitch Lab finished Mirage running 4600 RPM 66 MPH GPS.
Thanks,
Jeff

I would think that changing to the Edelbrock heads would gain you 50+HP. Would be a great choice if you have the $$...
I would guess 3 to 5mph increase... :drink:

RLW 10-31-2005 10:51 AM

Re: Head advice on BBC
 
Does anyone have the flow numbers for the Edelbrock Marine heads?
Where is the substantiating information that warrants this recommendation?
Anodizing, Inconel and price sure makes them sound attractive but what are you getting beyond that?

Pat McPherson 10-31-2005 11:00 AM

Re: Head advice on BBC
 

Originally Posted by RLW
Does anyone have the flow numbers for the Edelbrock Marine heads?
Where is the substantiating information that warrants this recommendation?
Anodizing, Inconel and price sure makes them sound attractive but what are you getting beyond that?

Edelbrock does have flow numbers on their web-page. How accurate there are ???
I would say that they have to be a hell of a lot better than peanut port heads... :rolleyes:


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