[randyb12]

Update... loud tap after cam swap, 427w stroker

Flat tappet cam went flat so I swapped it for a Comp cams retro roller kit. I didnt use the Comp lifters: Standard Ford spider style... Instead I used Lunati link bar roller lifters.
Now I have a very loud tap that matches engine rpm.
It seems to come from the pass side of the engine. I checked lifter/block clearence, double checked rockers...
I am hopeing the bad cam didnt cause some other damage!
You all have any suggestions shourt of tearing the engine down and going through the whole thing?
Thanks.
https://www.dropbox.com/gallery/42617308/1/Truck pics?h=03f467
No sign of valve to piston contact...
Video of valvetrain:
http://dl.dropbox.com/u/42617308/video of truck motor sept 26 2011.MTS

 

[jopes]

since you went roller, are your valve springs up to the task of the roller cam?

 

[randyb12]

Yes, AFR heads, Scorpian roller rocker arms and Lanati valve springs rated for the Voodoo cam with the same basic specs as this comp cam. Simular lift and dur.
It runs and revs fine just the loud tapping.
Well I guess I will readjust the valves then pull the intake if that doesnt fix the tapping. I hope I dont have to pull the engine and tear into the bottom end...

 

[cajunrebel]

I just did a valve adjustment on my buddies 302 with adjustable roller tipped rockers Saturday night. We had to prime the oil pump while adjusting the rockers since they are hydraulic. Otherwise they bleed down and you over adjust them. Took a bit to do it but the results were night and day.

 

[BigWheelz]

Check for a broken valve spring or missing needle bearings in a rocker.

 

[randyb12]

Thanks for the feedback I willl let you all know what I find out today.

 

[randy2112]

No luck so far. pulling intake tomorrow...
sound clip: http://dl.dropbox.com/u/42617308/truck tapping noise.wma

 

[jopes]

holy hell dude. Stop running that engine.

If it did not have this noise before then I am pretty sure your timing is off. Unless your runing like 14:1 compression.

That thing starts extremely hard. Whats up with that?

 

[Sw1tchfoot]

From the description I was thinking it was probably a rocker arm but, man that's loud. Let us know what it was.

 

[goladdgrs]

Post the actual part numbers you used to see if you have the proper matched components. It sounds pretty severe. Pictures of the valvetrain setup might help too.

opc1:

 

[randy2112]

Lifters: http://www.summitracing.com/parts/LUN-72335LUN/
Cam: http://www.summitracing.com/parts/CCA-CL35-426-8/
Pushrods: http://www.summitracing.com/parts/CCA-7963-16/
Rockers: Scorpian roller/needle bearing trunun, 1.6 intake 1.72 exhaust
Heads AFR 185
I will put up pics tomorrow... I checked all the clearences and made sure everything operated correctly during assembly. I may be pushing it on the exhaust lift. The springs are supposed to be good for .60 lift. But I am pushing 0.604 on the exhaust.

 

[cajunrebel]

Did you prime the oil pump as you adjusted the lifters? If they are not full of oil then adjusting your rockers will collapse them and make your valves stay open.
I could not hear the sound clip as I am on a govt computer. But my buddies 302 sounded horrible after he adjusted them worng.

 

[randy2112]

I readjusted them today, after it ran for a few seconds... No help.
I will be tearing into it tomorrow to see what I can find... I will post pics.

 

[goladdgrs]

Prior to dissasembly check for coil bind, with the valve open you should have at least .060" of clearance.

Also, you posted a split ratio rocker arm setup, with 1.6 on intake and 1.7 on exhaust. The 1.7 exhaust actually increases your effective lift and given the fact that it doesn't sound like a "tick", and more like a "clack" and your +.600" lift, you may be experiencing piston to valve interference. Of course those are just ideas, there are plenty of possibilities.

Before tearing the engine down also check for proper valvetrain geometry between the roller rocker cup and tip. The pushrod should fit perfectly in the cup and not be offest or at an angle. The tip should ride perfectly center to the valve stem tip.

It should look like this...

Where these heads preassembled from the factory by AFR or did you assemble them with other valvetrain components?

Do you know the spring pressure? We gotta make sure your spring pressure is adequate for that camshaft profile.

opc1:

 

[jopes]

TO me that thing cranks excessively hard.

and runs rough.

thats screaming something is wrong in the timing.

 

[Fireguy50]

7.700" Pushrods: http://www.summitracing.com/parts/CCA-7963-16/

Ford 5.8L roller cam pushrods are 7.567" from the factory

My cam story
http://fullsizebronco.com/forum/showthread.php?p=560680

 

[randy2112]

Prior to dissasembly check for coil bind, with the valve open you should have at least .060" of clearance.

Also, you posted a split ratio rocker arm setup, with 1.6 on intake and 1.7 on exhaust. The 1.7 exhaust actually increases your effective lift and given the fact that it doesn't sound like a "tick", and more like a "clack" and your +.600" lift, you may be experiencing piston to valve interference. Of course those are just ideas, there are plenty of possibilities.

Before tearing the engine down also check for proper valvetrain geometry between the roller rocker cup and tip. The pushrod should fit perfectly in the cup and not be offest or at an angle. The tip should ride perfectly center to the valve stem tip.

It should look like this...

Where these heads preassembled from the factory by AFR or did you assemble them with other valvetrain components?

Do you know the spring pressure? We gotta make sure your spring pressure is adequate for that camshaft profile.

opc1:

The 0.604 lift is with the added lift from the 1.72 rocker ratio.
Springs were the ones from Lunati for the Voodoo flat tappet cam... Need to find the part no before I can tell you anything.I installed the springs before the heads went to the machinist... I got the heads used so he needed to clean them up.

 

[BigWheelz]

holy hell dude. Stop running that engine.

X2 Your base timing is off, your compression is sky high, or your starter is very weak.

Check the bottom of your valve covers....sounds like a rocker is hitting the valve cover to me..

An old ******* trick is to remove the valve covers and run the engine, you can see which rocker is ticking prety quick this way. Be sure to get some oil deflectors....this makes a heck of a mess.

 

[randy2112]

Hi, Did some checking on the math... Intake is 0.596 and exhaust is 0.576.
Plenty of spring travel, more than 0.060 clearence.
I think the springs for the flat tappet cam are too light:
Description Single w/ Damper
OD 1.450''
ID 1.080''
Seat Load,Height/Load 1.750''/115
Open Load, Height/Load 1.250''/250
Coil Bind 1.080''
Max Lift 0.610''
Rate 270
BTW:
The wimpy start is from a too small battery that is old. It starts out fine then starts to slow down fairly quick.
CR is 10.63:1.

 

[jopes]

you said you installed the springs, did you measure spring height, spring pressure on the seat and when fully open?