I have a .30 over flat top pistons, stock crank, Dove c heads,comp cam kit k34-330-4, magnum roller rockers 79 block 460. It doesn't leak or burn oil motor has always had the oil changed less than 10k miles on it.

ran it for awhile...always ran good, and made good oil pressure and made no noises until notice a valve train noise(tick/clatter) like a valve noise. It was two bent pushrods. They bent because the factory pushrods weren't change with the upgrades. Change them for stronger pushrods but noise still persist but engine runs strong and doesn't loose power.

Funny thing is it that the noise is non existent at start-up until the engine is hot/engine temperature and seems the hotter the oil gets the louder the noise.. AND only around the 2000 RPM range. Anything higher or lower it wont make the noise. (I hope this makes sense.)

Also, properly broke this new cam in with a high zinc content oil....

I have tried everything from 5-30, 10-30, 10-40. 15-40 and 20-50. Nothing

ANYONE HAVE ANY IDEAS?

 

Valve springs are tired and should have been replaced with the cam and rocker mods.... mods will tend to find the weakest link which you have already found with the pushrods.

 

Actually that was my next step but before I did that I thought I would post my situation.

Would worn spring make noise only when engine is warm and at certain rpm's?

 

Well, when metal is warm it tends to be looser than stiff, cold metal.

 

One more thing I forgt to mention, after the engine is hot and I come to a stop or come under 1500-200 0 rpm's or just park it while the engine is hot & running of course it doesn't make the noise.

Only when running at around 1500-2000 rpm's.

I apologize if I'm not making sense.

 

Ok guys,so I'm being told it might be a wrist pin or ticking lifter both of which sound expensive.

What are your takes?

To clear up last message, the ticking only happens under load at about 1800-2300 rpm's when the motor is hot.

Sorry for the confusion.

Oh one more thing I forgot to mention was that I had to replace all the push rods because it bent 2. They bent because the were factory push rods. it was doing this noise before aswell.

 

Anyother comments or suggestions?

Your help is greatly appreciated.

What about air/fuel ratio? I believe this causes pinging/tapping at higher rpm's right?

Thanks

 

Anybody know of a good performance tuning shop in northwest Indiana. Especially one that specialize in ford motors.

Thanks !

 

Tigger!
Any luck with the tapping? Was it a lifter? This kind of sounds like what I am experiencing.

 

Nope , it was detonation. Timing was the issue.

 

I was going to say detonation might be your culprit. Correct timing will help, but with flat top pistons and pre '72 cast iron heads I have a feeling your compression ratio is way to high to be running pump gas.

Food for thought from what I can find....DOVE heads are something like 76cc. Later heads are 90cc+. If you do have the 76cc heads with flat top pistons and 30 over bore, your compression ratio is right about 11:1 which is really high for pump gas with iron heads. Something more along the lines of 10:1 would be more acceptable for 93 octane.

With later heads with say 92cc your compression ratio would be around 9.5:1 which would likely run with properly advanced timing and 93 octane.

 

Sounds about right. I'll be honest I don't know much about timing but I was told that initial timing was ok but when it would advance to fast and high which would make it detonate.

I hope it makes sense. Lol