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Head Swap! 289->351w

  • Thread starter Thread starter Jake69
  • Start date Start date Jul 24, 2011
J

Jake69

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May 26, 2011
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Paradise, CA
Jul 24, 2011
#1
  • Jul 24, 2011
  • #1
1969 coupe 302 shortblock w/ 289 heads, .280 intake .295 exhaust cam

I plan on changing my heads from stock(?) 289 to ported and polished 351w heads. I have a stock 302 shortblock. I have new head gaskets ready to go, along with the heads themselves, but as far as rocker arms and pushrods I'm not sure if they're interchangeable, and even if they are, are they're worth using to save a little cash? If I buy new rocker arms, should I go to a higher ratio? Any feedback is appreciated.
 

PoppyMod

Member
Jun 27, 2010
617
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Severna Park, MD
Jul 24, 2011
#2
  • Jul 24, 2011
  • #2
Jake69 said:
1969 coupe 302 shortblock w/ 289 heads, .280 intake .295 exhaust cam

I plan on changing my heads from stock(?) 289 to ported and polished 351w heads. I have a stock 302 shortblock. I have new head gaskets ready to go, along with the heads themselves, but as far as rocker arms and pushrods I'm not sure if they're interchangeable, and even if they are, are they're worth using to save a little cash? If I buy new rocker arms, should I go to a higher ratio? Any feedback is appreciated.
Click to expand...


Hi,
In my view, unless you are getting a very good deal (read as "almost free") on the heads, I would go with Windsor JR, if sticking with iron heads. Years ago, 351 heads with their smallish valves (1.78/1.54), were pretty much our only choice. Today, we have so many more affordable heads. The JR's with their 1.94/160 valves, is so much better "untouched" than the 351 head. If add a little bowl blending and shave to arrive at a 10.0 CR, you've got a 'killer" street head.
As far as the 1.7 rocker ratio, you should always check the P/V clearance and the push rod geometry. Sure you'll gain a tiny bit, but unless you do all of the other stuff, you're wasting your money.
Good Luck!
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Jul 24, 2011
#3
  • Jul 24, 2011
  • #3
Back when this was the trick setup, Ford offered pop-up pistons to keep the compression ratio up, otherwise it'll be lousy. Such pistons are still available, and not too expensive. I'd avoid shaving the heads to do this, if you cut them enough to matter, you'll have alignment problems with the intake.
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Jul 24, 2011
#4
  • Jul 24, 2011
  • #4
The 70s called and they want their crappy heads back.

Not to be mean, but I do agree with the others. Possibly if a pro did the port work and he's a friend that will sell them to you for $200 it might be worth it. Otherwise the odds are GT-40s are better - you should be able to get them for about $200 if they are in great condition, less with high miles.

Best way to go is aluminum if you have the cash. Heads are the one thing to spend money on if you want a good performing engine. You still have to make sure all the components match up properly, but heads are really the key.
 
J

Jake69

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May 26, 2011
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Paradise, CA
Jul 24, 2011
#5
  • Jul 24, 2011
  • #5
The heads were ported and polished by Andy Granatelli, and I already own them. They're a lot nicer than you think.
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jul 25, 2011
#6
  • Jul 25, 2011
  • #6
blkfrd said:
Where's Paradise, Ca? I didn't think CA had any Paradise anymore. I'm in Anaheim Hills.

Anyhow, what is your comp ratio now? You will loose about 3/4 of a point of compression unless the 351w heads have been decked some. Measure the chambers and see what they are. They should be in the 61cc area unless they have been shaved. What year are the 289 heads? Later 289 heads had larger chambers so you may not loose a lot of compression.

Andy Granatelli?...interesting. You can see from my sig info that there is nothing wrong with a set of well preped 351w heads.
Click to expand...

Hey Chr.....
Where have you been lurking these days?

 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jul 25, 2011
#7
  • Jul 25, 2011
  • #7
Jake69 said:
The heads were ported and polished by Andy Granatelli, and I already own them. They're a lot nicer than you think.
Click to expand...

OK. So what size valves and do you know the CCs? You'll need to know thisand few other tidbits when you start thinking CR.
 
J

Jake69

New Member
May 26, 2011
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Paradise, CA
Jul 25, 2011
#8
  • Jul 25, 2011
  • #8
1.94 intake 1.6 exhaust on the 351w heads, and they're 60ccs, my current heads are 1968s, so they're 63ccs.
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jul 25, 2011
#9
  • Jul 25, 2011
  • #9
Jake69 said:
1.94 intake 1.6 exhaust on the 351w heads, and they're 60ccs, my current heads are 1968s, so they're 63ccs.
Click to expand...

VG! So, how do you get to 10.0 CR? this will make it all pop! Depending on the cam, of course.
Nice!
 
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