SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: santeerob619 on August 23, 2013, 10:33:27 AM

Title: 540 build advice
Post by: santeerob619 on August 23, 2013, 10:33:27 AM
I'm looking at a bow tie block right now with a 4.5 bore. I already have a brand new 4.25 Molnar crank and 6.385 rods. With that bore and stroke it will make a 540. The guy is also selling a set of 681 casting bow tie heads. They are 105cc open chamber heads with 380cc intake runners! Will that be a good head for a 540? I want to run a tunnel ram with dual 850s and a roller cam. Possibly a blower, but most likely a tunnel ram. I'm looking for advice.

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Title: Re: 540 build advice
Post by: 81sprint on August 23, 2013, 06:09:43 PM
Ask madskillz he's running a blown 540


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Title: Re: 540 build advice
Post by: Just Electric on August 23, 2013, 10:33:02 PM
What are the cam specs with this combo and what is trying to take you for on $ end of it


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Title: Re: 540 build advice
Post by: santeerob619 on August 24, 2013, 07:26:15 AM
I am no where near choosing a cam yet. All I know is that I'm going with a hydraulic roller set up from Crower. The guy is asking $1800 for the bow tie block. I'm not interested in the heads anymore. I think a 540 will really get the tunnel dragster to scoot.

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Title: Re: 540 build advice
Post by: obnoxious001 on August 25, 2013, 08:57:45 PM
I'm looking at a bow tie block right now with a 4.5 bore. I already have a brand new 4.25 Molnar crank and 6.385 rods. With that bore and stroke it will make a 540. The guy is also selling a set of 681 casting bow tie heads. They are 105cc open chamber heads with 380cc intake runners! Will that be a good head for a 540? I want to run a tunnel ram with dual 850s and a roller cam. Possibly a blower, but most likely a tunnel ram. I'm looking for advice.

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Yep,, those heads are not for you. 

Is $1800 for a new bowtie block, or used?  If not, do some searching for Dart blocks, there have been some really good prices in the past couple of months. 
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