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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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1 1/2 or 1 5/8?

  • Thread starter Thread starter 5oh4fun
  • Start date Start date Jul 14, 2004
5

5oh4fun

New Member
Apr 8, 2004
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Delaware
Jul 14, 2004
#1
  • Jul 14, 2004
  • #1
I was wondering if there is a big difference in power between shortie headers? My engine is stoch with the typical mods: CAI, cat back, 75mm MAF, underdrive pullies, and 3.73's. I don't know that it will make that much of a difference. Thanks for any help.
 

RacEoHolic330

I like to dress like a pretty girl
15 Year Member
Mar 4, 2003
4,014
1,698
203
Allentown, PA
Jul 14, 2004
#2
  • Jul 14, 2004
  • #2
If you're gonna buy new headers, don't even bother with 1 1/2". You'll get much more out of the 1 5/8" with room to grow.
 

drgn5.0

Founding Member
Mar 13, 2001
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Jul 14, 2004
#3
  • Jul 14, 2004
  • #3
agreed
 

maverick0716

Founding Member
Jan 12, 2002
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Chilliwack, BC, Canada
Jul 14, 2004
#4
  • Jul 14, 2004
  • #4
On a stock engine the 1 1/2" headers will make the same if not more than the 1 5/8s. But if you plan on modifying the car more (h/c/i) than the 1 5/8 are the way to go.
 

04sleeper

Founding Member
Jun 22, 2002
2,674
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89
Dallas, TX
Jul 14, 2004
#5
  • Jul 14, 2004
  • #5
I put 1 1/2 inch equal length shorties on my car and lost 4 hp and 3 ft lbs.
Also tried 1 5/8 inch shorties and lost 5 hp and 6 ft lbs. Went back to the stock headers and picked up the HP again. I would wait until you get some heads before you get the headers. They will just hurt you for now.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
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128
Saint Louis, MO
Jul 14, 2004
#6
  • Jul 14, 2004
  • #6
89sleeper said:
I put 1 1/2 inch equal length shorties on my car and lost 4 hp and 3 ft lbs. Also tried 1 5/8 inch shorties and lost 5 hp and 6 ft lbs. Went back to the stock headers and picked up the HP again. I would wait until you get some heads before you get the headers. They will just hurt you for now.
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90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
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Dallas, GA
Jul 14, 2004
#7
  • Jul 14, 2004
  • #7
I'm not a fan of equal length shorties, they tend to loose bottom end with no real gain over standard shorties, plus the other issues, nevermind.

A 1 1/2" runner won't flow as much maximum airflow as a 1 5/8" runner, but the velosity in the 1 1/2" runner will be higher. Your setup won't max out the flow of the 1 1/2" shorties, but you will get more volosity out of them which will mean more power down low.

Unless you have replaced the factory H pipe with thier old style cats with at least a 2 cat midpipe, your better off with the stockers.

If your going to replace both the headers and midpipe, I wouldn't even think about shorties of any kind, just get longtubes.
 

cleanLX

Founding Member
Jan 17, 2001
976
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Jul 14, 2004
#8
  • Jul 14, 2004
  • #8
I would not spend the money to put aftermarket shorties on a stock motor.
Long tubes on the otherhand...
 
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