Re: TDC Question
[Re: 6PAX]
#3169376
08/21/23 10:27 AM
08/21/23 10:27 AM
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Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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18 is excellent. pics are correct: rotor at 5 o'clock/reluctor dead even with the magnet no matter how the slot is clocked but in this case it is parallel which that is a good starting point & is correct most of the time. EDIT some dists have different bottom tang to rotor clocking
Last edited by RapidRobert; 08/22/23 11:01 AM.
live every 24 hour block of time like it's your last day on earth
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Re: TDC Question
[Re: Cab_Burge]
#3172509
09/03/23 09:07 AM
09/03/23 09:07 AM
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Joined: May 2005
Posts: 2,072 Apollo, PA.
B1MAXX
top fuel
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top fuel
Joined: May 2005
Posts: 2,072
Apollo, PA.
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Ditch the thermostat, try again a fan blowing at the engine compartment/grill is always helpful.
But that being said at 10 minutes the cam is probably broke in.
Did you check the timing during this time?
Last edited by B1MAXX; 09/03/23 09:10 AM.
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Re: TDC Question
[Re: B1MAXX]
#3172562
09/03/23 12:21 PM
09/03/23 12:21 PM
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Joined: Jan 2003
Posts: 5,731 Detroit area
6PAX
OP
master
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OP
master
Joined: Jan 2003
Posts: 5,731
Detroit area
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Ditch the thermostat, try again a fan blowing at the engine compartment/grill is always helpful.
But that being said at 10 minutes the cam is probably broke in.
Did you check the timing during this time? No, I didn't check the timing. It was running so smooth I didn't think the timing was an issue. The engine is not in the car, it is on a dolly. I had a box fan blowing through the radiator and a couple of fans blowing on the sides of the motor. I tried running it again a little while ago without a thermostat and it only took 6 minutes to overheat this time. Again, with straight water. That being said, I think the first run with the t-stat I had in it it appears to have been a bad t-stat. Couldn't get it to open doing a test in a cup of boiling water. I am going to get another new t-stat to put in it. What temp t-stat should I get, 180 or 195?
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Re: TDC Question
[Re: 6PAX]
#3172577
09/03/23 01:05 PM
09/03/23 01:05 PM
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Joined: May 2005
Posts: 2,072 Apollo, PA.
B1MAXX
top fuel
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top fuel
Joined: May 2005
Posts: 2,072
Apollo, PA.
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180 But it should cool without a thermostat. I was just curious how close you where on the timing. What kind of fan on rad? Any shroud?
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Re: TDC Question
[Re: 6PAX]
#3172627
09/03/23 05:39 PM
09/03/23 05:39 PM
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Joined: Jan 2003
Posts: 19,544 Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,544
Las Vegas
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If the timing is to retarded it will cause the coolant temp to rise quickly and significantly. Advance it some and see what it does, easy enough to try.
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: TDC Question
[Re: 6PAX]
#3173279
09/06/23 09:11 AM
09/06/23 09:11 AM
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Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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If it cranks/starts OK at 22 BTDC when hot I would limit the total (checked with vac adv (if used) plugged) at 34-36 with the FBO plate.
live every 24 hour block of time like it's your last day on earth
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Re: TDC Question
[Re: RapidRobert]
#3173283
09/06/23 09:17 AM
09/06/23 09:17 AM
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Joined: May 2005
Posts: 2,072 Apollo, PA.
B1MAXX
top fuel
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top fuel
Joined: May 2005
Posts: 2,072
Apollo, PA.
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I always set the total timing at 3000-4000. Usually with one hand on the throttle and the otter holding the gun (or get a helper). If you have 20 min run time its broke in.
Last edited by B1MAXX; 09/06/23 09:18 AM.
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Re: TDC Question
[Re: B1MAXX]
#3173318
09/06/23 11:59 AM
09/06/23 11:59 AM
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Joined: Jan 2003
Posts: 19,544 Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,544
Las Vegas
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The more initial you have the happier it will be, and as stated limit the total advance when done. But give it all the initial it wants/needs. Most racecars have the timing locked out, so they idle in the 30-40 range.
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: TDC Question
[Re: Al_Alguire]
#3173321
09/06/23 12:05 PM
09/06/23 12:05 PM
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Joined: Dec 2005
Posts: 12,318 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 12,318
Fulton County, PA
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The more initial you have the happier it will be, and as stated limit the total advance when done. But give it all the initial it wants/needs. Most racecars have the timing locked out, so they idle in the 30-40 range. Big cam, low vacuum, I don't even fool with it or band-aid around it. Lock it out and use the electronics to retard it as needed, when needed. Street car, small or stock cam? Sure.
Last edited by CMcAllister; 09/06/23 12:07 PM.
If the results don't match the theory, change the theory.
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Re: TDC Question
[Re: 6PAX]
#3173324
09/06/23 12:13 PM
09/06/23 12:13 PM
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Joined: Dec 2005
Posts: 12,318 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 12,318
Fulton County, PA
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Looking at the top two pictures, would you say cylinder #1 or #6 is on TDC? With the balancer set on TDC, the top pic are the lifters for #1 and the bottom for #6. The second pair of pics are after I rotated the balancer 360 degrees. Again, #1 is top pic, #6 bottom pic. Watch the valves. As the engine rotates, the intake will open as the piston travels down on the intake stroke. As it reaches BDC the intake will close. As the piston comes back up it will be on the compression stroke. At TDC, drop the distributor shaft in it correctly and set the distributor in with the rotor on #1.
If the results don't match the theory, change the theory.
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Re: TDC Question
[Re: 6PAX]
#3173343
09/06/23 01:19 PM
09/06/23 01:19 PM
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Joined: Jan 2003
Posts: 75,282 A gulag near you.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,282
A gulag near you.
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Ditch the thermostat, try again a fan blowing at the engine compartment/grill is always helpful.
But that being said at 10 minutes the cam is probably broke in.
Did you check the timing during this time? No, I didn't check the timing. It was running so smooth I didn't think the timing was an issue. The engine is not in the car, it is on a dolly. I had a box fan blowing through the radiator and a couple of fans blowing on the sides of the motor. I tried running it again a little while ago without a thermostat and it only took 6 minutes to overheat this time. Again, with straight water. That being said, I think the first run with the t-stat I had in it it appears to have been a bad t-stat. Couldn't get it to open doing a test in a cup of boiling water. I am going to get another new t-stat to put in it. What temp t-stat should I get, 180 or 195? I had this same problem breaking in a cam a long time ago, my headers turned cherry red and it boiled over. Found out later about the timing issue causing it, once you get the engine running and you bring it up to 2000 RPM throw the light back on it and adjust the timing so it's at 34-36 degrees and run it there. Most distributors mechanical advance isn't high enough at 2k unless you've modified it yourself. Next cam I helped a friend with he saw the samething, fired it up and the headers were staring to glow at 2k , advanced the timing and the headers stopped turning red.
Mainstream Media is the new Pravda
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