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-   -   HP500 buildup questions (https://www.offshoreonly.com/forums/general-boating-discussion/252403-hp500-buildup-questions.html)

Joe308 05-02-2011 09:24 PM

I was surprised that my HP500's had std BBC connecting rods. Merc racing was nice enough to fax me a few pages from their manual last year and I see diagrams showing both std BBC and Carillo style rods. Wonder if the real "racers" got the better internals?

Griff 05-03-2011 01:48 AM

Carbed 500hp's have the Gm rods. The second or third year of the 500EFI they started getting Manley rods.

Dean Ferry 05-03-2011 06:13 AM


Originally Posted by axapowell (Post 3389972)
HP 500's came with stock Chevy rods. They are fine up to about 600hp. As for the Cam, listen to Merc, I tried the Gils on the dyno back in 2006 and it did show some signs of reversion plus they killed the hp. I have had NO problems with the CMI's, but I am in fresh water too.

You may want to rethink the blower option. You could easily get 650 with a small blower and low boost. You could also continue to run the Gil's!

BTW I run 89 pump gas!

Dave

Hey Dave,
Dean here, how's life in A-bay? Running 89 octane, what is your C/R?? I can get a killer deal on some AFR heads, I'm just trying to decide which size to get.....
Thanks,
Dean

Joe308 05-03-2011 09:03 PM

I hear AFR came out with a cast iron head, but are all you guys running AFR's aluminum? We're probably going to stick with heavy metal. :)

axapowell 05-03-2011 09:22 PM


Originally Posted by Dean Ferry (Post 3392969)
Hey Dave,
Dean here, how's life in A-bay? Running 89 octane, what is your C/R?? I can get a killer deal on some AFR heads, I'm just trying to decide which size to get.....
Thanks,
Dean

9.25:1 minus the aluminum heads, easier to dissipate the heat, so net around 8.75:1.

You will also save 60 lbs. per motor.

Dave

axapowell 05-03-2011 09:24 PM

Mine are 305...CNC'd from AFR to 315cc.

Dave

Dean Ferry 05-04-2011 05:34 AM


Originally Posted by axapowell (Post 3393880)
9.25:1 minus the aluminum heads, easier to dissipate the heat, so net around 8.75:1.

You will also save 60 lbs. per motor.

Dave

Dave,
Thanks for the info, I'll try to PM you today. My mom and step-dad, who lives in Potsdam, wants us to come up for a summer vacation, maybe we'll bring the boat, and you can show us around A-bay.....

axapowell 05-04-2011 08:11 AM


Originally Posted by Dean Ferry (Post 3394017)
Dave,
Thanks for the info, I'll try to PM you today. My mom and step-dad, who lives in Potsdam, wants us to come up for a summer vacation, maybe we'll bring the boat, and you can show us around A-bay.....


Would be happy to give you the "Tour". If we plan it out right, I can get a few of the OSO TIBBC together for a gathering!

Dave

CIG3 05-04-2011 04:08 PM

The AFR Aluminum head (Anodized) are a great investment. Also look at Stainless Marine exhaust. Will make the power and last. Less expensive than CMI and no leaks.

articfriends 05-04-2011 05:18 PM

The biggest thing that will hold your build up from making really good numbers is going to be the world heads, they are STONES compared to afr's
http://racingfeed.com/downloads/chevy_flow_data.pdf
The merlins flow 320 intake/201 exhaust at .600 lift
The afr 315's flow 380 intake/296 exhaust at .600 lift
I built my first 540 almost 10 years ago running a procharger m-3 and I used MERLIN heads, the motor did not even break 700 hp under boost , when I freshened it a few years later I made 950 hp after switching to the afr's and a cam 1/2 size bigger than previously (designed by Bob Madera/RMBUILDER). Now, I know you are not building a blower motor BUT head flow is head flow and Merlins almost identical to out of the box rectangle port factory heads. Its no secret that heads that flowed 30% better than my Merlins were a big help in gaining 35% more power, this hold true in normally aspirated applications too, it WILL help make the difference between you making 540 hp and being dissappointed and making 650 hp and being satisfied, Smitty


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