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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Timing after headswap

  • Thread starter Thread starter 97GTSTANG
  • Start date Start date Nov 12, 2004

97GTSTANG

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May 25, 2000
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Nov 12, 2004
#1
  • Nov 12, 2004
  • #1
I have a 02PI headswap on my 97GT and I am currently running the steeda T/A, i have it set at 13degrees. I was wondering if thats too much since the car has a higher compression ratio (is it 10:1?). Will raising the timing cause it to lean out or get richer? Or should I just keep it back at 10degrees? I do use 93Octane
 
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chimchim

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May 14, 2004
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Nov 12, 2004
#2
  • Nov 12, 2004
  • #2
97 Stang, Do a search on this subject. I just asked this two days ago and there were many helpful answers. Pretty much most people said to leave it stock 10*. One guy that can only get 91 Octane actually got a custom tune for -2*. You'll make up in compression what your buddy with a stock 99-04 will gain with a TA.
 

97GTSTANG

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May 25, 2000
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17
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Nov 12, 2004
#3
  • Nov 12, 2004
  • #3
Thanks Chim, so is the compression now a 10:1?
 
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chimchim

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#4
  • Nov 12, 2004
  • #4
I've seen anywhere from 10.0 -10.5 to 1 on here. I guess it depends on your block and your heads and how they come together.
 

97GTSTANG

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Nov 12, 2004
#5
  • Nov 12, 2004
  • #5
I will bring the timing back down to 10 and see how much difference it makes.
 

CanadaStang

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Sep 7, 2003
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Nov 12, 2004
#6
  • Nov 12, 2004
  • #6
97GTSTANG said:
I will bring the timing back down to 10 and see how much difference it makes.
Click to expand...
If you have no pre detonation issues, I wouldn"t be concerned.
 

CanadaStang

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Nov 12, 2004
#7
  • Nov 12, 2004
  • #7
97GTSTANG said:
I have a 02PI headswap on my 97GT and I am currently running the steeda T/A, i have it set at 13degrees. I was wondering if thats too much since the car has a higher compression ratio (is it 10:1?). Will raising the timing cause it to lean out or get richer? Or should I just keep it back at 10degrees? I do use 93Octane
Click to expand...
Advancing the timing has no effect as to rich/lean.Although richening the a/f mixture will cool the combustion chamber a certain amount, which in turn will help pre detonation if the timing is too far advanced.
 

97GTSTANG

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Nov 13, 2004
#8
  • Nov 13, 2004
  • #8
i dropped the timing back to 11 degrees and the car seems to drive a little better and less ticking and ratling from the engine, i dont know if its in my head but seems like it helped.
 

CanadaStang

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Nov 14, 2004
#9
  • Nov 14, 2004
  • #9
97GTSTANG said:
i dropped the timing back to 11 degrees and the car seems to drive a little better and less ticking and ratling from the engine, i dont know if its in my head but seems like it helped.
Click to expand...
Well thats good to hear. Just noticed you have the zex 75 shot, I was doing some research on the Zex, seams like a good system. How do you like it?
 

97GTSTANG

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May 25, 2000
852
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Nov 14, 2004
#10
  • Nov 14, 2004
  • #10
LIke the Zex kit, it was really easy to install and u can change the jets and get up to 125HP shot. I am just using 75hp shot now. When i get it tuned I will boost is up to 100Hp shot.
CanadaStang said:
Well thats good to hear. Just noticed you have the zex 75 shot, I was doing some research on the Zex, seams like a good system. How do you like it?
Click to expand...
 

CanadaStang

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Sep 7, 2003
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#11
  • Nov 14, 2004
  • #11
97GTSTANG said:
LIke the Zex kit, it was really easy to install and u can change the jets and get up to 125HP shot. I am just using 75hp shot now. When i get it tuned I will boost is up to 100Hp shot.
Click to expand...
Is that the dry shot? It's great to hear from someone who has tried the Zex, it sure seamed like a nice system but I was holding off till I had chance to ask someone who had it, just to see if it was as good as it looks on paper. Thanks for the info
 

97GTSTANG

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May 25, 2000
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Nov 14, 2004
#12
  • Nov 14, 2004
  • #12
Yes, it is a dry kit. Got an MSD on the way so its rpm activated.


CanadaStang said:
Is that the dry shot? It's great to hear from someone who has tried the Zex, it sure seamed like a nice system but I was holding off till I had chance to ask someone who had it, just to see if it was as good as it looks on paper. Thanks for the info
Click to expand...
 

CanadaStang

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Sep 7, 2003
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Nov 14, 2004
#13
  • Nov 14, 2004
  • #13
97GTSTANG said:
Yes, it is a dry kit. Got an MSD on the way so its rpm activated.
Click to expand...
Very cool indeed.
 
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