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Top Dead Center

Old Jan 13, 2012 | 09:28 AM
  #1  
GreenCamaro13's Avatar
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From: IDAHO
Car: 89 rs
Engine: 2.8 v6
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Top Dead Center

ok so i was getting help from this very smart guy but im sorta stummped on what or how to even do the top dead center part. here is what he posted:

Normally the factory faces the rotor in cylinder ones general direction. But considering how you don't know who's been in this car or what they've done, it can be anywhere. Just set it to TDC and see where the rotor is pointing, and that post is your #1.

--Thank You Bradley--
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Old Jan 13, 2012 | 11:34 AM
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Re: Top Dead Center

What exactly are you doing?
Is the distributor out for some reason?

He is talking about Top Dead Center - top of the compression stroke, NOT TDC for the exhaust stroke. Both of these TDCs will have the 0* timing mark on your damper lined up with your timing tab.
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Old Jan 13, 2012 | 12:08 PM
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Re: Top Dead Center

i removed my intake manifold to reach the injectors and he said i should fix them while im there.
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Old Jan 13, 2012 | 01:38 PM
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Car: 1988 IROC-Z Camaro, 1981 Trans Am
Engine: 350 TPI, 301 N/A
Transmission: 700r4, 350thm
Re: Top Dead Center

To get the correct TDC, i always tell people the thumb trick. Remove spark plug 1 and put your thumb over the hole. Have someone turn over the engine in short intervals until your thumb is blown off the hole. This way youll know you are in the compression stroke. Try not to put your thumb IN the hole- baddd idea. lol

Also very important, confirm TDC by using something like a flathead screwdriver. Put it thru the sparkplug hole to check for TDC. The balancer can slip causing false TDC readings. This is very important.

What he means by:

"Normally the factory faces the rotor in cylinder ones general direction. But considering how you don't know who's been in this car or what they've done, it can be anywhere. Just set it to TDC and see where the rotor is pointing, and that post is your #1."

Hes saying that when youve confirmed TDC on the COMPRESSION stroke, which ever post on the cap that the rotor in the distributor is your 1st cylinder. So you do your firing order from that post on - clockwise. Usually, and thats factory setting, the rotor will face cylinder 1. But technically it doesnt have to. if youve pulled the dizzy out tho, its best to put it in facing cyl 1, so you know for future reference.
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Old Jan 13, 2012 | 03:40 PM
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Re: Top Dead Center

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Old Jan 13, 2012 | 04:55 PM
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Re: Top Dead Center

Originally Posted by GreenCamaro13
i removed my intake manifold to reach the injectors and he said i should fix them while im there.
??? Injectors aren't under the intake manifold.
... and "fix them" fix what ?
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Old Jan 13, 2012 | 04:58 PM
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Re: Top Dead Center

Originally Posted by 305sbc
??? Injectors aren't under the intake manifold.
... and "fix them" fix what ?
He has a v6, the injectors are under the upper intake manifold.

I think he wants to pull them and have them cleaned.
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Old Jan 13, 2012 | 05:02 PM
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Transmission: 700R4
Axle/Gears: 3.25:1
Re: Top Dead Center

Originally Posted by bradley23150
He has a v6, the injectors are under the upper intake manifold.

I think he wants to pull them and have them cleaned.
That's fine. So why did the distributor have to come out for that?
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Old Jan 13, 2012 | 05:11 PM
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From: Charlotte, NC
Car: 1988 IROC-Z Camaro, 1981 Trans Am
Engine: 350 TPI, 301 N/A
Transmission: 700r4, 350thm
Re: Top Dead Center

Originally Posted by 305sbc
??? Injectors aren't under the intake manifold.
... and "fix them" fix what ?
I wondered the same thing until I looked at what engine he had, then i knew what he meant. So you werent the only one. lol

But you cant really "fix" injectors per se, do you mean clean them? Have you ohmed them out? If you did, what were the results? You may need a new one(s). (beyond repair)

Can I ask what made you do all this? I mean, what problem(s) you were having.

And, "So why did the distributor have to come out for that?" Another good question lol

I will say this: if you did pull the distributor, IMO you should change the pickup coil while you can. They arent fun to test, and if that does fail on you youd have to pull the entire distributor again anyways. So jump the gun and "fix" the problem before it happens! lol they arent expensive anyways, and well worth the frustration saved too. Thats just what i would do tho.
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Old Jan 13, 2012 | 05:20 PM
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Re: Top Dead Center

Lol, the distributor didnt come out for that, I was telling him how to ensure that his firing order is correct after being adjusted.

Here is the thread:

https://www.thirdgen.org/forums/tech...-camaro-2.html

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Old Jan 13, 2012 | 05:30 PM
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From: Fairview Heights Illinois
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Axle/Gears: 3.25:1
Re: Top Dead Center

Holy crap!
..."adjusted firing order"

AFAIK rotors are designed so that they can only go on one way.
...but I'm going to have to stay out of this one.
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Old Jan 13, 2012 | 06:12 PM
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Re: Top Dead Center

i just explaioned everything in my thread as stated by bradley, if nyone could shine some light upon me
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