spark plug wire mixup
11-17-2016, 08:46 PM
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spark plug wire mixup
5.7l 350 tpi
Mixed up the spark plug wire order.
Re-wired them based of one wire that I didn't take out and was in cylinder 8 (based of the diagram i was using). Idles with no problems but i want to be 100% sure its correct because im not so sure about the random online firebird diagram I found.
Does anyone have the real firing order for this motor?
Also how am I suppose to know the orientation of the distributor?
theres no indication of front or back, do I just assume the last guy who owned the car put it in facing the correct way?
i think i was following the picture from this thread
https://www.thirdgen.org/forums/tech...new-motor.html
Mixed up the spark plug wire order.
Re-wired them based of one wire that I didn't take out and was in cylinder 8 (based of the diagram i was using). Idles with no problems but i want to be 100% sure its correct because im not so sure about the random online firebird diagram I found.
Does anyone have the real firing order for this motor?
Also how am I suppose to know the orientation of the distributor?
theres no indication of front or back, do I just assume the last guy who owned the car put it in facing the correct way?
i think i was following the picture from this thread
https://www.thirdgen.org/forums/tech...new-motor.html
Last edited by truckguy; 11-17-2016 at 08:49 PM.
11-17-2016, 10:48 PM
#2
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Re: spark plug wire mixup
The diagram in the link you posted is correct. Just confirm that the wire you didn't remove is actually on the No. 8 spark plug ON YOUR ENGINE.
Once you confirm this, it doesn't matter where on the distributor cap the No. 8 wire is plugged into. Just use that wire as your starting point and plug the No. 4 plug wire into the next tower CW from No. 8, No. 3 CW from No. 4, and so on.
You cannot assume anything. That will get you into trouble every time.
Once you confirm this, it doesn't matter where on the distributor cap the No. 8 wire is plugged into. Just use that wire as your starting point and plug the No. 4 plug wire into the next tower CW from No. 8, No. 3 CW from No. 4, and so on.
You cannot assume anything. That will get you into trouble every time.
11-18-2016, 01:15 AM
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Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: spark plug wire mixup
1-8-4-3-6-5-7-2 ALL gen 1 sbc use this firing order. Doesn't change, always will be (unless you have a special grind cam). So, if you know for sure that one wire is correct, just use the firing order to locate the rest of the wires correctly. If your engine is idling good with no pops or "missing", you can be pretty sure the sequence is correct, but as Paulo says, never assume anything and check to be sure.
11-18-2016, 10:57 AM
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Re: spark plug wire mixup
1-8-4-3-6-5-7-2 ALL gen 1 sbc use this firing order. Doesn't change, always will be (unless you have a special grind cam). So, if you know for sure that one wire is correct, just use the firing order to locate the rest of the wires correctly. If your engine is idling good with no pops or "missing", you can be pretty sure the sequence is correct, but as Paulo says, never assume anything and check to be sure.
Well thats the thing Im not exactly sure that the no. 8 was correct.
The reason I have to believe is to assume the guy did a correct job, which is not the best reason. Im also not sure about his work because he had numbered the wires with tape and they are in some CRAZY order
...
11-18-2016, 10:58 AM
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Re: spark plug wire mixup
The diagram in the link you posted is correct. Just confirm that the wire you didn't remove is actually on the No. 8 spark plug ON YOUR ENGINE.
Once you confirm this, it doesn't matter where on the distributor cap the No. 8 wire is plugged into. Just use that wire as your starting point and plug the No. 4 plug wire into the next tower CW from No. 8, No. 3 CW from No. 4, and so on.
You cannot assume anything. That will get you into trouble every time.
Once you confirm this, it doesn't matter where on the distributor cap the No. 8 wire is plugged into. Just use that wire as your starting point and plug the No. 4 plug wire into the next tower CW from No. 8, No. 3 CW from No. 4, and so on.
You cannot assume anything. That will get you into trouble every time.
I know for a fact I didnt move 8. but the only thing is how do i know that the last guy wired 8 was correctly.
I need to know some way to check if 8 was correct... and thats the big dilemma bc theres not really any way of checking to my knowledge.
11-18-2016, 02:37 PM
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Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
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Re: spark plug wire mixup
Check your timing. Disconnect the timing connector and see where your base timing is reading. If at 8 BTDC then you know the number 1 plug is correct and go from there. As stated before, if you don't have a noticeable miss or any backfiring then the wires are correctly laid out. If the wires were mixed up, you would certainly notice it when starting and accelerating. HTH!
11-18-2016, 04:34 PM
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Re: spark plug wire mixup
Check your timing. Disconnect the timing connector and see where your base timing is reading. If at 8 BTDC then you know the number 1 plug is correct and go from there. As stated before, if you don't have a noticeable miss or any backfiring then the wires are correctly laid out. If the wires were mixed up, you would certainly notice it when starting and accelerating. HTH!
since Im still learning how motors work, I thought of the possibility that theres a change maybe two spark plugs being swapped may cause a small noticeable issue.
If thats not the case the motor is prob fine since I just drove it around the block. The only weird thing is sometimes after I fire it up for the 3rd time it fires up REALLY fast, which to me would seem like spark plug related...but it did that before I bought the truck. TBH I just want a new motor and dont really care for this tpi.
Again I dont know much about motors and it seems pretty challenging to crank the motor and look at/analyze the piston strokes. Idk I guess I can give it a try.
thanks