Vortec Head Swap

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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primary cutting is of the valve guide for .530 seals

the spring pocket is just a kiss.

since the company is asking questions, my guess is they dont do much head work. my guy simply asked me which rockers i was running so he knew what studs to install, and if I had springs or did he need to supply.
 

scoflaw

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Jun 2, 2010
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Buy the parts Comp recommends. Drop everything off at the machine shop, he can mock it up to determine what and how much needs to be cut
 

FreeBeeTony

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May 15, 2002
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Not sure I could get enough $$$............I enjoyed it though!
Proof will be when I launch and put it under load.........sounds great in the backyard on the hose!
 

Chrisravosa36

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Aug 16, 2015
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Buy the parts Comp recommends. Drop everything off at the machine shop, he can mock it up to determine what and how much needs to be cut

I think thats what il have to do, il print out the cam spec sheets and see what he thinks.
 

Chrisravosa36

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primary cutting is of the valve guide for .530 seals

the spring pocket is just a kiss.

since the company is asking questions, my guess is they dont do much head work. my guy simply asked me which rockers i was running so he knew what studs to install, and if I had springs or did he need to supply.

I get the point now...

I was more worried about the valve coming into contact with the piston, but it seems coil bind is the bigger issue here.
 

Scott Danforth

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I get the point now...

I was more worried about the valve coming into contact with the piston, but it seems coil bind is the bigger issue here.

yep, coil bind leads to broken rocker studs, and broken springs and mashed oil seals.

even with .600" lift cam, only way valve can hit the piston is if you break a timing chain or the cam shaft breaks.
 

Chrisravosa36

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yep, coil bind leads to broken rocker studs, and broken springs and mashed oil seals.

even with .600" lift cam, only way valve can hit the piston is if you break a timing chain or the cam shaft breaks.

Gotcha,

Heres a few more questions in the meantime.

For the carb spacer should I get one that has the 4 holes in it lined up with the throttle valves or one that is open all the way? I'm guessing the 4 holes?

Also, once I get this all together and running, I understand I have to retorque the cylinder heads, how long do I have to wait to retorque them? WIll running it for 5 minutes and letting it get up to temp do the trick? Or should I take the boat out for the first time and run it for an hour and retorque them? Its sorrta a PITA because I have to remove the manifolds to get access o the bottom head bolts to retorque them, but it is what it is.

I also read on other peoples forums that apparently there is a coolant bypass on the vortec intake??

Im guessing I can get intake plugs at any auto parts store for all the holes I wont be using on my intake.
 

Chrisravosa36

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Aug 16, 2015
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Set it n forget it. Retorque not necessary.

Ive seen on many threads and forums that if not retorqued people have had there head gaskets fail prematurely? Is this claim false? Id rather not retorque, but if necessary I will
 

Chrisravosa36

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Aug 16, 2015
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Also had my heads machined and they took seven thousand off, will I still be able to use stock pushrods?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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50,327
buy good head gaskets and you dont need to retorque

as for the carb spacer, a phenolic 4-hole that transitions to your specific intake manifold (2 slots or open plenum)

I like to blend mine with a die grinder. as like this
fetch
 

Chrisravosa36

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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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50,327
buy fel-pro gaskets at your local parts store or from summit or Jegs, etc. vs unknown gaskets from fleabay.
 

Bondo

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buy fel-pro gaskets at your local parts store or from summit or Jegs, etc. vs unknown gaskets from fleabay.

Ayuh,....... I can get 'em right at my local Napa, especially if I give 'em the Fel-pro part #,.......
 

Chrisravosa36

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Aug 16, 2015
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Quick question, how do I bar over the engine if I have the water pump on the front? I cannot get onto the crank pulley??
 
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