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What Holley heads do I have?

  • Thread starter Thread starter Shadrack
  • Start date Start date Dec 5, 2005

Shadrack

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Aug 2, 2005
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Dec 5, 2005
#1
  • Dec 5, 2005
  • #1
I've been trying to find out what heads I have on my car. The only numbers I can see are on the front of the drivers side head. The number reads..... 12157...... does anyone have a clue what model/size these heads are? Where can I find the serial number (or is that the serial number)?

Any help would be appreciated.
Thanks!
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
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B.C. Canada
Dec 6, 2005
#2
  • Dec 6, 2005
  • #2
when did you buy the heads? They only make 1 set of heads now it looks like for the fords a 2.02 1.6 valve ones. I have holley systemax II heads from 5 years ago they were 1.94 1.6 valves. http://users.erols.com/srweiss/tablehdc.htm#Ford scroll down to windsor then down to holley systemaxthose are the flow numbers for the 1.94 intake valve heads
 

Shadrack

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Dec 6, 2005
#3
  • Dec 6, 2005
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I bought the car with the heads already on it. I think they are the Systemax heads, not the Systemax II heads.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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Dec 6, 2005
#4
  • Dec 6, 2005
  • #4
Do they have stud or ped mount rockers?
 

Shadrack

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Aug 2, 2005
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#5
  • Dec 6, 2005
  • #5
View attachment 495348
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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PA
Dec 7, 2005
#6
  • Dec 7, 2005
  • #6
Stud mount...

They are most likely the new series head, which are very good and respond well to some porting. Biggest I have is the cheap locks they use.

The best way to confirm would be measuring the valves. Holley only makes 2 stud mount heads, 300-573 and a 300-575 they have different size intake valves. You could call Holley Tech, although I find them hit or miss at times. They will need the numbers that are cast on the head inbetween the rockers like you have pictured.
I ran the 300-575 and they are a really nice head, and if I remember correctly it had 12157 on the front. I am trying to find my old pics
 

Busted07

I need my gorilla to be about an inch longer.
Nov 15, 2005
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Dec 7, 2005
#7
  • Dec 7, 2005
  • #7
Shadrack said:
View attachment 495271
Click to expand...


do you have any other pictures of your engine bay? im trying to decide how to route some things, and i like how yours looks from that picture
 
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