Pinging engine

S

Scarab155

Member
Grump: Just got done with getting my 1967 Olds Cutlass 442 ready for the street. It was a long and (at times) painful struggle. Not being an Ace Master Mechanic I usually had to do everything twice -- first the wrong way and then the correct way. Well, I took the car out for a brief test drive to see if it would go, steer and stop -- Yes, everything works - however, the engine is pinging when I apply throttle. Not floor it -- just accelerate. The engine is a .030 over Olds 400 big block with 9.5:1 pistons and an Engle cam that has lift of 310 intake 320 exhaust and @ .050 duration 226 intalke and 230 exhaust. lobe centres 110. Installed striaght up. Set the initial timing at max vacumn since the pointer only goes to 10 degrees BTDC and this cam wanted more. So, do I advance more or retard more. I know I could just try and run down the road a bit until I get it right -- I'll still do that but I'm looking for some starting direction. Thanks in advance Craig
 
Scarab155 said:
Grump: Just got done with getting my 1967 Olds Cutlass 442 ready for the street. It was a long and (at times) painful struggle. Not being an Ace Master Mechanic I usually had to do everything twice -- first the wrong way and then the correct way. Well, I took the car out for a brief test drive to see if it would go, steer and stop -- Yes, everything works - however, the engine is pinging when I apply throttle. Not floor it -- just accelerate. The engine is a .030 over Olds 400 big block with 9.5:1 pistons and an Engle cam that has lift of 310 intake 320 exhaust and @ .050 duration 226 intalke and 230 exhaust. lobe centres 110. Installed striaght up. Set the initial timing at max vacuum since the pointer only goes to 10 degrees BTDC and this cam wanted more. So, do I advance more or retard more. I know I could just try and run down the road a bit until I get it right -- I'll still do that but I'm looking for some starting direction. Thanks in advance Craig
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start by setting the ignition advance ,idle timing at 6-7 degrees btdc and work from that point, adjustable timing tabs and timing tape should help, just because its designed for a ford, chevy, chrysler, doesn,t prevent its use on an olds, retarding the cam 4 degree's won,t hurt either ignition spark should be bright blue and impressive, if its, weak,narrow, yellow or red theres a problem so research the cause, verify the coil and voltage

viewtopic.php?f=70&t=1015&p=1864&hilit=+tabs#p1864

without a fuel pressure gauge and an adjustable return style fuel pressure regulator with a return line installed your basically restricted to guessing, and chances are very good youll have major problems, you need the engine timing set correctly and you need to learn how to tune carbs and correctly read spark plugs
step one is getting the fuel pressure rock steady at 5 psi, then get the carbs floats and jets set correctly, so you get plugs that look like this

good
14.jpg


too lean
24.jpg

too rich
7.jpg



http://forum.grumpysperformance.com/viewtopic.php?f=55&t=211

http://forum.grumpysperformance.com/viewtopic.php?f=55&t=635

http://forum.grumpysperformance.com/viewtopic.php?f=70&t=202

http://forum.grumpysperformance.com/viewtopic.php?f=70&t=1015
 
Grump:- Once again -- you 'da Man !! -- I started it down around 5 degrees BTDC and ultimately ended up around 8 degrees BTDC ..no more pinging and (like magic) the power has returned !!
 
IM,ALWAYS GLAD to help you gentlemen AVOID the learning curve hurtles, and get to the answers faster when I can help :mrgreen:
 
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