340 rebuild,timing,intake manifold

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Westtexdart

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Almost finished with 69 340 rebuild.I've read so much about timing that I'm questioning myself. I had no. 1 at TDC,motor right side up,mark on cam at 6:00, mark on crank at 12:00, centerline with crank and cam,both valves closed on no.1,oil pump drive slot lines up more or less with left front intake bolt hole,now does the rotor line up with no. 1 on dist? Also I was planning to install a performer intake.From what I've read the factory 69 intake performs better ?
 
Westtexdart said:
Almost finished with 69 340 rebuild.I've read so much about timing that I'm questioning myself. I had no. 1 at TDC,motor right side up,mark on cam at 6:00, mark on crank at 12:00, centerline with crank and cam,both valves closed on no.1,oil pump drive slot lines up more or less with left front intake bolt hole,now does the rotor line up with no. 1 on dist? Also I was planning to install a performer intake.From what I've read the factory 69 intake performs better ?
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With the engine set up like you have it, you can make no.1 on the distributor anywhere you want. Just want to position the dist. in a fashion that allows you room to turn it when you put the timing light on it after you get it running. The postion of the slot has nothing to do with the timing of it. From the factory, no.1 was at about the 7 o clock postion when viewed from the top of the dist. Then wire it clockwise 1-8-4-3-6-5-7-2.
 
The rotor should face the same way the oil pump drive points,with the motor a tdc on #1 cylinder.
Directly at the left front intake manifold bolt.

Also I wouldnt use the performer intake,unless you are talking about the performer rpm air-gap or the performer rpm.It has smaller ports than your 340 heads.
 
If you had the cam gear set on 6:00 O'clock and the crank gear on 12 0'clock that is #1 exhaust TDC. You need to have both cam and crank gears set on 12 O'clock for it to be on tdc compression stroke. Everything else is right.

Note: Your valves may have been closed making it appear to be on compression stroke even though it was on exhaust stroke but that was probably because the lifters were bled down.
 
SGBARRACUDA said:
With the engine set up like you have it, you can make no.1 on the distributor anywhere you want. Just want to position the dist. in a fashion that allows you room to turn it when you put the timing light on it after you get it running. The postion of the slot has nothing to do with the timing of it. From the factory, no.1 was at about the 7 o clock postion when viewed from the top of the dist. Then wire it clockwise 1-8-4-3-6-5-7-2.
Click to expand...
I'm so glad some one else besides me understand this.
 
Can someone elaborate on what fishy said, as my book says to line them at 6 and 12 o;clock. I did this, bolted on the heads and haven't put the lifters and rockers on yet will I be 180 out? Walt
 
Hi Walt. Most books seem to say to line them up at 6 and 12 O'clock. That does put the ignition timing 180 degrees out on #1 cyl.. All you have to do is spin the engine over one full turn and drop the dist. in pointing at #1 and now your in time. Remember the cam only turns at half the speed of the crank (that's the reason the cam gear is twice the size of the crank gear) so even if you align them up at 6 and 12 O'clock you spin the engine over exactly one full revolution they are now both at 12 O'clock.
 
Fishy, thanks for the speedy reply. So all I have to do is turn my crank bolt so the timing mark on the crank goes around one time and I'm at number 1 fire. They must tell you 6 and 12 because it is easier to align with a straight edge when the marks are close. WaltO:)
 
No problem Walt. Yep that's all you have to do. And I believe your right about why they tell you to do it that way. It is easier to see when you have them aligned using the 6 and 12 O'clock method. LOL
 
I did the cam at 6 and the crank at 12 and tried to crank the motor. It would not crank. Took the distributer out turned the rotor button 180* reinstalled the distributer and it fired right up. Don't ask me because I don't know either.
 
the why is when you do the 6 12 thing it is tdc no.6 which the 5th cyl to fire in the fire order or 180 of the dist.
 
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