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  • 1965 - 1973 Classic Mustangs -General/Talk-
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302 heads

  • Thread starter Thread starter 67Flashback
  • Start date Start date Jan 4, 2010
6

67Flashback

New Member
Jan 4, 2010
2
0
0
Jan 4, 2010
#1
  • Jan 4, 2010
  • #1
I have a 71 coupe that needs the valve seals replaced. The motor is not the original and it has an Edelbrock performer cam and intake. It also has headers with flowmasters. What I was wondering was, since I need the heads done, is there anything I can do to get more performance from them without spending a lot of money or is it even worth it? any help would be appreciated.
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Jan 4, 2010
#2
  • Jan 4, 2010
  • #2
Valve seals or guides?
You can replace the valve seals with out removing the heads.
You may be able to get a set of fresh performance heads, cast or aluminum for less than a stock rebuild.
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Jan 4, 2010
#3
  • Jan 4, 2010
  • #3
is there anything I can do to get more performance from them without spending a lot of money or is it even worth it? any help would be appreciated.
Click to expand...

Yes! Port-match the exhaust to the manifolds/headers, and remove any Thermactor bumps from inside the ports. It'll feel like you got a better cam. You can do this yourself in a couple hours, I did mine.

The exhaust ports of the 289/302 had an adequate design, but in practice there was usually a lot of casting flash around the opening, and the Thermactor bumps added later were so bad you'd think spies from Chevy put them there.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Jan 4, 2010
#4
  • Jan 4, 2010
  • #4
2+2GT said:
Yes! Port-match the exhaust to the manifolds/headers, and remove any Thermactor bumps from inside the ports. It'll feel like you got a better cam. You can do this yourself in a couple hours, I did mine.
Click to expand...

He can also replace the valve seals too himself. But if they need guides too................ and seats, & valves, springs.....................might as well buy new or secondhand aftermarket heads. It's a slippery slope with 40 year old heads.
 
C

C0V3R

Member
Feb 14, 2003
524
0
16
Australia
Jan 4, 2010
#5
  • Jan 4, 2010
  • #5
If you need to recondition the heads, I would get a quote/price before doing anything. It is likely to cost you a good portion of what a set of brand new aftermarket heads would cost.
 
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