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  • SN95 4.6L Mustang Tech

not exhaust issue - DETONATION

  • Thread starter Thread starter Torinalth
  • Start date Start date Apr 18, 2005
T

Torinalth

Founding Member
Jul 16, 2002
952
0
16
Clayton NC
Apr 18, 2005
#1
  • Apr 18, 2005
  • #1
well.... i was on course to replace my entire exhaust system due to either a loose header or busted cats, ratteling and all, but after working under the car this weekend and finding NOTHING, it dawned on me.... oh damn, thats detonation..... so yeah, few questions and concerns.

I will be replacing my plugs with autolite 764s before this weekend, seafoam is going in the tank tomorrow when i fill up with premium to see if it goes away, after that and the plugs i think i should be ok... if not i'll be doing the coilpacks..... also, something is kinda bugging me.... i was rear ended a bit ago, and remember one thing that has kinda faded, but now might be pertinant.... the shop guy said (as he handed me the keys) "everything is fine, suspension was aligned, dyno showed 231 (before mods) and 14:1 AF. at the time i thought cool 231 hp... but now with my new breathing mods (sig) i wonder if this "14:1" AF he mentioned is causing me to be WAY to lean with my mods and pushing my detonation?

1- knowing i have been detonation for a while i think (just never realized it was det) what did i prolly screw up

2- when i do my plugs do i need to coat them with anthing? threadlock? lithium grease? or just go in bone dry? any tips?

3- when i drop the seafoam in, is there anything i should look for as signs for issues with the block/heads/valves?

4- is my AF (if it is 14:1) a REALLY bad thing and warrent some emergency tuning? i wasnt planning on getting a preditor till another 5-6 months...

anything else i should be thinking of?

Torinalth
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
134
Apr 18, 2005
#2
  • Apr 18, 2005
  • #2
I use light anti seize on plug. I also use silicone dielctric compound on electrical mating surfaces.

Great article on changing plugs at www.bullittarchive.com
 
T

Torinalth

Founding Member
Jul 16, 2002
952
0
16
Clayton NC
Apr 19, 2005
#3
  • Apr 19, 2005
  • #3
bump for hopefully some help on the other issues

Torinalth
 

ADRENLN

Active Member
Apr 16, 2003
2,342
3
49
NJ
Apr 19, 2005
#4
  • Apr 19, 2005
  • #4
i was wondering the same thing about my 02 gt. ive had a light ticking for a year and a half that i thought was exhaust leak or somthing. detonation didnt even cross my mind.now i dont know. what did yours sound like. oh and why was your a/f so high, isnt that high for an 02 gt?
 
T

Torinalth

Founding Member
Jul 16, 2002
952
0
16
Clayton NC
Apr 19, 2005
#5
  • Apr 19, 2005
  • #5
well, i think i remember a preditor thread that said ideal was like 12.5:1. so that would make the AF a good bit high, then whatever my mods did to change it from that point. my car was tuned by the repair shop when i was rear ended (pretty sevear).

my detonation sounded like a light metalic clinking. my immediate thought was tht i had a tock in my heat shield for my cats (had a small rock lodged in my cover of the cats on my old thunderbird) so it is kinda like putting a pebble in a empty soup can then just kinda shake it around. its not LOUD and does NOT stand out as "Oh crap something is wrong with my engine" my biggest issue was that it sounded like it was under me, hence my thought of exhaust.

but yeah, if anyone else has any input i'd greatly appreciate it.

Torinalth
 
T

Torinalth

Founding Member
Jul 16, 2002
952
0
16
Clayton NC
Apr 19, 2005
#6
  • Apr 19, 2005
  • #6
well the seafoam is in the tank (bout 2/3 can) and dropped in 93 octane and the detonation seemed to disapear... so i will prolly be using midgrade for a bit and try 87 again with the new plugs to see if i still need to run mid or high test. anyone else have any thoughts to my issues above? please?

Torinalth
 
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