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351w Top End Overhaul - Advice

Old 08-09-2013, 11:19 AM
  #31  
67mustang302
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You can get Scorpion full roller rockers for about $250 for a whole set. Otherwise the Comp roller tips.

Definitely get the right length pushrods, bad geometry causes all sorts of problems.
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Old 08-09-2013, 12:05 PM
  #32  
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Thanks guys, I'll look into full roller options but will likely just go for the roller tips with this setup.

You mentioned to get the right springs, should I not get the already assembled Victor Jr.'s? I can get the bare ones and piece together everything comp cams recommends for which cam I choose if needed.

Are there any other OTS cams that anyone would recommend besides the Xtreme 270? I've only looked at Comp Cams because I'm most familiar with them and know they're pretty good.

Payday is today so I'm looking to place an order soon!

Edit: Can I re-use my head bolts? I imagine they're fine, but don't know if I need different bolts for aluminum heads. I know the torque will be less.
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Old 08-09-2013, 12:15 PM
  #33  
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I'd buy a set of ARP head bolts.

And bare heads is a better way to go, since you can get the right valve springs rather than being locked in to what you have.
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Old 08-09-2013, 12:20 PM
  #34  
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Thanks. Are the ARP bolts needed or a recommendation? Trying to trim my budget.

Also, I just now realized that the Victor Jr's won't work for my application... The exhaust ports are raised and square, rather than the rectangular opening my hedman headers have. I need them to match up with my existing exhaust setup

Edit: also to clarify since summit's site can be confusing. When buy heads do I have to buy two or do they come as a set? Some say sold individual and some say pair without a dramatic price difference.

Last edited by 4reboy; 08-09-2013 at 12:55 PM.
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Old 08-09-2013, 12:55 PM
  #35  
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The raised exhaust ports are not a big deal.My headers fit just fine.The port opening matching the headers can be an issue though..Most all aftermarket heads have squarish ports instead of rectangular like most ford headers..In my case I even had a mismatch with my bigger 1 3/4 super comp headers...There are many things to consider when buying heads more than just looking at peak flow numbers..It looks like you are doing your homework..Keep studying..lol

As for rockers I would really go with a full on roller rocker.They aren't that much more for a decent rocker like a scorpion.. I had issues with my headgaskets leaking oil and antifreeze when I first assembled my engine..Talking with ARP they told me to increase the torque to normal ford torque values and not the lower numbers they recommended in the instructions.That along with some new felpro 1011-2s and no more leaks.

Last edited by frdnut; 08-09-2013 at 01:00 PM.
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Old 08-09-2013, 03:01 PM
  #36  
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ARP head bolts are more a recommendation, but proper torque on certain parts of the engine is essential. With ARP bolts you know exactly what you're getting, and they're very rugged. The older factory stuff was typically grade 8, which was fine for lower power levels, but as combustion pressures go up, more load is placed on the head bolts when the plug fires.

Also the stronger bolts with newer gasket technology means the need to retorque is not an issue, and things are less likely to work loose over time. Torque stays consistent.

Hardware for the heads, rods and crank are absolutely somewhere you never want to skimp in an engine. Every time I do anything, I never even give a thought to hardware costs any more....I get what it needs and it costs what it costs (incidentally, the longer you do this the more you'll realize that hardware is a big "nickel and dime you to death" part of the nickels and dimes).

You don't HAVE to get Vic. Jr's, you just need a good head that's appropriate for the engine. So TFS 192cc High Ports or FAC 190's, AFR 185 or 195, Vic. Jr's etc etc (ideal ports size for what you need is like 185-200cc intake port, but up to a 210-215 will work too). Edelbrock, Dart, AFR, TFS are some of the most common of the good heads, and you should be able to find something on Corral. Actually, since the AFR 195 is newer for SBF, you might look to see if someone is selling the 185's so they can upgrade.

And yeah, don't worry about headers too much, SBF runs the sq/rect. type exhaust ports that work with most headers fine, so unless you get something out of the ordinary, it will probably be ok. Raised port just raises the exhaust ports up on the head, but bolts the same headers up.

Look around and see what's available for used heads.
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Old 08-09-2013, 04:32 PM
  #37  
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Originally Posted by 67mustang302
And yeah, don't worry about headers too much, SBF runs the sq/rect. type exhaust ports that work with most headers fine, so unless you get something out of the ordinary, it will probably be ok. Raised port just raises the exhaust ports up on the head, but bolts the same headers up.
So using my rectangle headers agains the square ports is okay to do? It won't cause an exhaust leak? I imagine the square ports would be wider than the width of the rectangle pipe.

And on Summit the cost is for one head or one pair? This definitely makes a huge difference in the price and some wording is not as clear as it could be.

I will also look into used heads but I would hate to get something damaged and not know.
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Old 08-09-2013, 04:42 PM
  #38  
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Depends on the head listed on Summit, typically heads are around $1,300-1,600 assembled for a pair.

And as long as the header isn't smaller than the port, you're fine. The slight step actually helps combat reversion.
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Old 08-09-2013, 10:03 PM
  #39  
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What I suggest is look at the recommended header gasket for whatever head it is you are looking at..If you get the gasket number you should be able to find the dimensions for the port size if the manufacturer doesn't list the port size..Compare that to your header gasket or header port opening...I made a paper outline around my vic jr ports and then laid it over my header openings to see how bad the match up was.I would try to get this as close as possible..I would also be careful on the corral..I bought my heads there supposedly just freshened up..They were a mess when I got them and I had to have them remachined and the springs were a joke. In the end I saved a few bucks but only because I live in Canada and parts are stupid expensive up here.
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Old 08-09-2013, 10:08 PM
  #40  
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Originally Posted by 67mustang302
Depends on the head listed on Summit, typically heads are around $1,300-1,600 assembled for a pair.

And as long as the header isn't smaller than the port, you're fine. The slight step actually helps combat reversion.
I understand this theory with the intake manifold but don't quite grasp it for exhaust?..To me you want max flow out of the head and all the way to the tail pipe. This assumes correct sized primary pipes on the headers of course.
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