Thread: After fix-Now I got PING or POP...SBC 400

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DAMN... I'm ready to bring this engine to the scrap yard. It just seems like every time I fix something on it something else goes wrong. Now I've got a pop or pinging sound that seems like it is coming from underneath the intake manifold. The weird thing though is I just reinstalled the intake manifold after fixing a broken pushrod and the engine fired right up after the fix. I verified the firing order was correct and everything seemed allright. I had my intial timing set at 13 BTDC w/ vac plugged and idle at 1000 RPM. The engine ran great for 15 minutes w/ no noises whatsoever. I then loosened my mixture screws on my Holley to get the highest idle less than a minute later the engine started to POP and PING. I have never had this problem before whatsoever. I tried putting some 104 plus octane boost in it but I don't think that helped either. I turned the mixture screws back but it just keeps pinging. I know this a common subject and I tried to do a search here but couldn't find a good enough answer.
Today I started the car after work and everything seemed fine until the popping started again about 2 minutes of running. When I try to retard or advance the timing it has no affect on the popping. Could I need new plugs?(there shorty accel header plugs) Could there be a problem w/ my MSD? I don't know what to check now. I'm getting pissed now and I usually never loose the cool. I haven't pulled my plugs to see what the look like as they are very hard to get out due to the fact that the heads are equipped with angle plug sockets-the headers make it very difficult to remove or install these when there on the engine. Anybody got any tips or a checklist that I can go through. All replies are much appreciated.

Originally posted by onemangang
DAMN... I'm ready to bring this engine to the scrap yard. It just seems like every time I fix something on it something else goes wrong. Now I've got a pop or pinging sound that seems like it is coming from underneath the intake manifold. The weird thing though is I just reinstalled the intake manifold after fixing a broken pushrod and the engine fired right up after the fix. I verified the firing order was correct and everything seemed allright. I had my intial timing set at 13 BTDC w/ vac plugged and idle at 1000 RPM. The engine ran great for 15 minutes w/ no noises whatsoever. I then loosened my mixture screws on my Holley to get the highest idle less than a minute later the engine started to POP and PING. I have never had this problem before whatsoever. I tried putting some 104 plus octane boost in it but I don't think that helped either. I turned the mixture screws back but it just keeps pinging. I know this a common subject and I tried to do a search here but couldn't find a good enough answer.
Today I started the car after work and everything seemed fine until the popping started again about 2 minutes of running. When I try to retard or advance the timing it has no affect on the popping. Could I need new plugs?(there shorty accel header plugs) Could there be a problem w/ my MSD? I don't know what to check now. I'm getting pissed now and I usually never loose the cool. I haven't pulled my plugs to see what the look like as they are very hard to get out due to the fact that the heads are equipped with angle plug sockets-the headers make it very difficult to remove or install these when there on the engine. Anybody got any tips or a checklist that I can go through. All replies are much appreciated.

id pull the valve covers back off and check those valves again.

Thanks fellas,
Just a few thoughts...I kind of thought it would it might also help to say how I exactly did things.

1)Valve setting: Removed all rockers from both heads and replaced 4 lifters w/ 4 new ones because 2 had popped out. Other 2 were replaced just because I thought they might have been bad because they didn't have "spring"-I then proceded to set the valves per Crane cams instructions by just starting at #1 and set them on the drivers side and then switch to pass. side.

2)Timing: Installed distributor w/ oil pump shaft pointing towards exhaust on #5 cylinder and rotor pointing directly towards #1 cylinder. The dizzy dropped right in.Brought engine up on compression stroke on #1 cylinder. The engine timing tape read 8 degrees BTDC. Started the engine and it fired right up. Put a timing light on right away and the timing tape read somwhere between 5 and 10 "AFTER TDC"-to the left of the 0 on the tape.Then turned dizzy counter clockwise to advance timing to 13 degrees BTDC and idle was at 1000RPM. Ran fine for 15 minutes Is this correct?

Is there a better way to set your valves than that Crane Cams way? I've heard of other ways... that just seems easier for me to understand. Any other thoughts would be great. I'll try setting the valves again though or maybe pulling the dizzy out and retiming again.

Here's a stabe at timing issues. But the poping taht you described
as happen to me. Damn lobe polished right off. But that may not be ur case. When u set ur timing with a light run the engine above 3 grand and set it. Do you have the 4deg. retard/advance
crank sproket yet another thing I have learned is if it was to perform at the advance/retared side they would machine it there
set it in the stock position. What head do u have aftermarket or
stock. What intake????

I was also wondering u said crane cams and u broke a pushrod.
Check your valve train geometry your rockers should never leave the center of the valve stem.Another thing with that broken push rod did your piston smack the valve it may have bent the valve and that also might be the pop u hear if u bent the valve it may not be seating properly. Do a compresion check if u dont get it figured out maybe it will help figure out where to start if u have a valve that s not sealing. Dont junk that 400 i am building one at the moment and i may need ur info

initial timing, base timing and total timing is confussing to me,
I have always set my timing at 3 grand maybe i am lucky but it always worked for me. YOU have any site that would help me better understand timing

thanks Denny that helped out alot

Thanks guys for your replies...in response to your comments about the valve being bent.

1) wouldn't the negine make noise as soon as the engine starts w/ a bent valve.

2) I also wrote the timing procedure kinda wierd on the previos post. I meant to say that I drooped the dizzy in w/ the timing tape reading 8 degrees BTDC and when I fired the engine it read between 5 and 10 AFTER TDC. The engine was idling at around 600 rpm and running a little rough so advanced the dizzy to 13 BTDC and it ran great for 15 minutes until I messed w/ the mixture screws.

3) I'm running a Edelbrock EPS idle to 5500 intake w/ aluminum aftermarket heads w/ 2.02- 1.60 valves

The reason I ask about the heads and intake is this what happen to me


(1) Torker 2 intake


(2) dart 230 cc runner heads

they didnt mate creating a lean condtion four out side runners i could see the 1/16 gap pulled the intake and the four inside runners I could see where it didnt seal. Just a thought

Ping pop????

Did a rocker back off??????


p.s. if your gonna trash that 400, i have an open trash can...hehe.

keep us posted

Thanks guys for the replies...Denny W. I would love to set the timing again but the engine pings right away when I start it. I know it's not good to have that go on for very long. I wish I had more engine diagnotic tools like a Vac guage and a compression gauge. I guess I'm going to have to break down and get some. Thanks guys for your help. I'll get to work and see what I come up with. It's got to be either...

1)Timing issue
2)Bent valve
3)Valve setting

Nobody commented on the crane cams way of setting valves, does anyone else have a different way?

Denny W.,

Yeah thats what I did, I just brought #1 up on comression stroke and adjusted the intake and exhuast on #1 and then I just kept moving on down the line adjusting the intake and exhaust on 3-5-7-2-4-6-8...You dont have to find TDC on the rest of the cylinders each time you adjust them do you? I just adjusted the intake when the exhaust was just opening and adjusted the exhaust when the intake came full open and then nearly closed.

When you say the carbon glowing right away were is that happening? In the combustion chambers? On the plugs themselves? I guess I don't get that part. Let me know....And thanks for your time.

Denny that's funny you say that about the coolant flow....when I fired the car up after I had fixed the broken pushrod and reinstalled the intake I forgot I had drained alot of the coolant out. I let the car run like I said for about 15 minutes....I remembered that I had not refilled the coolant up until 10 minutes after the car was running. I looked at the temp gauge and it read 190 degrees. Would that have been enough time to build that carbon up? I have the coolant all the way up now. Would seafoam help to remove them carbon deposits in the combustion chamber? I'm glad you pointed that out because that seems to fit the situation.
If seafoam is an option would you just pour it down the carb or let it get sucked up by the brake booster line? I have done this on my 94 blazer. I guess I'm just really worried about the ping when I start up. I don't want to ruin anything. I know when you put the seafoam in the engine needs to be running. What do ya think....