440 ordeal!

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66dartman

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I rebuilt the 440 from my co-worker's 71 Chally with a new crank, H beam rods, KB pistons, etc. I bought a Comp XE 268H cam & lifters for it. Block was not decked and the heads are out of the box eddy's. I installed the cam straight up. put the engine back in the car, no compression. comp says stock pushrods too long, but I don't see how since nothing was changed. Deck height and heads are the same as before. Pulled it back out after much talk with Comp techs. Any ideas? I am going to try a hughes cam. Checked timing marks several times, tried to get the cam to the 106 int. centerline but found it to be 27" off. comp says I'm full of it.
 
i agree. it sounds like you have the timing gear setup wrong. also did you check your lifter preload? you just might have too much and are keeping the vavles from closing.
 
What rocker arms were used? You didnt check rocker geometry from the sound of it either. No compression is somethign major overlooked. Not the cam. Even with lined up ring gaps it would have something. And Comp Cams are nver that far off. The worst I've ever seen from them was 2°. Out of many, many cams. I have found timing sets with mismarked or improperly placed keyways before. You also mention KBs... If they are hypers, did you gap the rings properly?(just an FYI there...) It sounds like maybe the valves are hanging open if there is no compression at all and you didnt check the sweep.
 
but I don't see how since nothing was changed
Click to expand...
Except the pistons, cam and heads.

Hyd. lifter cams are a pain by compare to a solid cam to time for some because they do not take into account the lifters movement. A possible couple with the timing gear on the wrong setting and your wacky way off.

Go over it again slowly and you'll find what your looking for.
 
What brand, type, style of timing set are you using? If you that cam 27 deg off, something is way wrong. Using the wrong timing mark on the crank side with a 3 keyway crank spocket maybe?
 
Thanks for the replies! The timing set is from mancini and it looks like a sealed power. I compared it to the original gears and it is right on. I gapped the rings according to the KB recommendations. Heads were on the engine when it was running before, and the same KB piston# was used. I have some years of experience but am baffled by this one. It almost seems that the cam pin was drilled in the wrong place. Moper, how do I check & change rocker geometry?
 
It sounds like your valve timing is out? I`ve seen many people put the crank timing gear on and align it by the woodruff key slot and not the corresponding mark on the gear. You can check the valve timing by rotating the crank around so that #6 ex. valve is closing and #6 intake is opening. Insert a 1/4 " spacer in between #1 intake rocker arm and the valve stem tip. Install a dial gauge so the plunger is just contacting the spring retainer and as perpendicular as possible. Allow the spring load to bleed down the lifter and then zero out the dial indicator. Rotate the crank clockwise until the dial indicator reads around .035. Don`t rotate the crank clockwise any more than necessary as you may bottom out the valvespring. The timing mark should be somewhere between 10* BTDC and TDC. If it doesn`t fall somewhere in that range then the valve timing is off. When you`re done with the check of the valve timing just rotate the crank counter clockwise to zero and remove the spacer. If you need help with rocker geometry there`s a tech article here in the archives by Dan Dvorak that`s really good.
 
66, Geometry is checked during assembly. I know you've gotten greasy before. You need to pull two valve springs and replace with checker springs, get two adjustable pushrods (I have two Comp Cams sets to check them) and you just rotate the engine thru it's cycle and see what the rocker tip does as it contacts the valve stem tip. It should start just inside the centerline of the stem, pass thru the center and go to the outside of centerline, then back during the lift event. It means basically at 50% lift, the rocker is perpendicular to the valve stem. My impression is, your pushrods are effectively too long and the valves are hanging open. What rockers are on it? They may be hitting the retainers and hanging them open too. On a mopar, the only way to adjust the geometry is rocker shaft location. Shims are cheapest way if you need to go up, which is the most common issue. Mancini has them in different thicknesses.
 
Moper, you are right on. I got my hands on a real big mic and checked pushrod length. It's 9.330. I have a length checker and to get zero lash I need 9.230. mancini has 9.250 pushrods, which they say are the stock length for a 440. as far as the cam not degreeing, I think I just didn't take into account the hydraulic lifter. So with the 9.250 pushrods, that should give me 020 preload. Lesson for me: Keep It Simple Stupid! Thanks to all for the help!
 
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