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Discussion Starter #1
Tuesday I put in NGK 4177 plugs. they are a cooler plug than the ford platniums. I was hoping tby changing the plugs i could get better times....WRONG!!! Not only does the computer not know what to do with them i FEEL the power loss difference. I not sure on HP numbers but it it a difference. hey JB when I put the plat's back in maby we can do it again. That might have attributed some to that spanking i took.................
 

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Discussion Starter #3
We tried resetting it all night on wensday to no avail....good thing i numbered all the plugs when i took them out
 

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Okay...so what happens when it comes time to change the plugs? Stick with OEM?

John
 

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thank god someone finally asked. I've been wondering the same since this thread started. Maybe we can never change the plugs.
 

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Discussion Starter #11
well i ran the plugs for three days and when i took them back out the car had been running extreemly rich and the plugs were fuel fouled.....go figure. i put the stock ones back in and it runs fine now
 

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I saw that in the Owner's Manual,about putting the original plugs back in the cylinders from where they were pulled. I will have to see what the reason is behind that. A colder range plug,just gets rid of it's heat quicker,which can help in high load/rpm situations. But they can cause fouling at lower RPMs. Maybe the computer was picking up more unburned fuel,and made an adustment....That is one tricky box!!
 

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When I installed my nitrous I went with a colder plug (autolite 764)and put the gap at 35. Been running the plugs for 3 weeks now and not having any problems.Runs strong on motor and very strong on the juice.
 

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This is from the maintenance manual

Note:
If an original spark plug is used, make sure it is installed in the same cylinder from which it was taken. New spark plugs can used in any cylinder.

If you follow the instructions completely, they want you to disconnect the battery when removing the Coil On Plug. This would mean your PCM would get reset of any learned settings. It doesn't say to reset the brain just remove the battery but if you leave it off long enough, around 15 mins that is what is going to happen. I guess you could make a case for resetting it if you have new plugs going in but not sure if I would with just checking them. I had these exact plus in my 95 T-Bird. Tried all kinds of different plugs just for the heck of it and NOTHING burned as even and clean as the factory Ford plugs. I ohmed the resistor plugs out after like 15,000 and they were all within .1 Ohms. Other ones I tried were not even that close when they were brand new.
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Mid Life Crisis #388



<font size=-1>[ This Message was edited by: Mid Life Crisis #388 on 2001-10-28 20:05 ]</font>
 

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Putting the "original" ie "used" plug back in the same hole is standard practice, always has been. The ECU will not know or care what pluge ins in the hole however. In Black's case, the colder heat range was probably too cold and you had poorer performance and fouling. I would recommend you try the Denso Irridium plugs. They seem to be the plug of choice on high output engines, especially forced induction. They have a very fine irridium electrode and supposed to work well. I'll give them a try when /if I go with a turbo, but for now, I'll stick with the stock heat range on the stock motor.

Brian
 

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How do the splitfire and rapidfire plugs work in the bullitt?

Is it worth the hassle?
 

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In a different car,I did try the splitfire plugs.I was a police officer then in Houston,Tx.The night before I clocked my parol car, a 1989 Ford Crown Victoria with the 351 HO motor and top end was 118mph.After changing to the splitfire plugs the next evening I made multiple attempts to reach my top speed,but to no avail.115 was all she would do.At that time those plugs where 9.00 a piece.I was not happy with my purchase.Dont waste your money.
 

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I had the rapidfire in my last car ( a 93 t-bird 5.0) and they were great!

I'm just worried about changing any plugs in this car after reading this post
 

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i never heard of denso plugs?
 
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