73 C20 Performance Engine Build

[bd]

The cam timing is off....

For zero advance, the crank gear is installed properly.  BUT, the zero timing mark at the outer circumference of the crank gear should align with the timing mark on the cam gear.  With the timing marks aligned, the crankshaft key should be at the 2 o'clock position.

[LTZ C20]

I know it looks warped to me too, but only around the dowel pin area. It's a brand new cover, out of the box and onto the engine.

Also, I will rotate the engine over to #1. Just haven't done it yet. Got to late last night and I work all week. Can't be up till 12 every night, I'll fall asleep on the job!

[bd]

Incidentally, consider installing a cam bolt lock plate.  And, apply red Loctite to the cam bolts at final assembly.

[LTZ C20]

The cam timing is off....

For zero advance, the crank gear is installed properly.  BUT, the zero timing mark at the outer circumference of the crank gear should align with the timing mark on the cam gear.  With the timing marks aligned, the crankshaft key should be at the 2 o'clock position.

I tried that, but it wouldn't align with the cam gear correctly. UNLESS I'm doing that wrong, which is a definite possibly.

[LTZ C20]

Incidentally, consider installing a cam bolt lock plate.  And, apply red Loctite to the cam bolts at final assembly.

Yea I got 1 of those too, the bolt holes don't line up. It's got the alignment for a flat tappet cam gear. Isn't anywhere near close for an OE roller cam. I didn't even choose the 1 I bought, 1 of the summit guys recommended, I told him it was for an OE roller, he said his info said it would fit, yet last night it was no where near close. So I called summit and a different guy said that since the OE rollers use a thrust plate behind the gear that a lock plate on the outside face of the cam gear is not needed. The outside lock plate is for when an engine isn't using a thrust plate, such as a flat tappet cam. I'm going to call their tech department back again today though to be double sure.

Also, I did use loctite.

[bd]

Incidentally, consider installing a cam bolt lock plate.  And, apply red Loctite to the cam bolts at final assembly.

Yea I got 1 of those too, the bolt holes don't line up. It's got the alignment for a flat tappet cam gear. Isn't anywhere near close for an OE roller cam. I didn't even choose the 1 I bought, 1 of the summit guys recommended, I told him it was for an OE roller, he said his info said it would fit, yet last night it was no where near close. So I called summit and a different guy said that since the OE rollers use a thrust plate behind the gear that a lock plate on the outside face of the cam gear is not needed. The outside lock plate is for when an engine isn't using a thrust plate, such as a flat tappet cam. I'm going to call their tech department back again today though to be double sure.

Also, I did use loctite.

All the lock plate does is guarantee that the cam bolts don't loosen.  It will also retain a cam thrust button when one is used.  However, a thrust button is redundant to a thrust plate.  No need to use both.

[LTZ C20]

Well that's good to know. Guess I won't call Summit then. I used loctite, grade 8 bolts and torqued to spec, so I shouldn't have an issue. I'll just be using the thrust plate then as it is now and forget about the lock plate. Like you said, both is redundant.

[LTZ C20]

Also can someone explain to me, due to my lack of experience, what the proper lubrication method is for the intake and head bolts.

Head bolts I've read get a lite coating of oil, others says some high temp sealer/loctite. The intake I've found says to use sealer/loctite also, but only on the more inboard, center section bolts.

Not sure which is the correct method for either set.

[bd]

All but the endmost intake manifold bolt holes open into the valley and are exposed to oil splash.  All of the head bolt holes open into the block water jackets and are exposed to coolant.  Chase all of the bolt hole threads then rinse them thoroughly with Berryman's B12 or similar - blow dry with compressed air.  If reusing head bolts DO NOT chase the bolt threads - use a wire wheel instead - even better, use new ARP bolts.  Apply ARP PTFE Thread Sealant, P/N 100-9904 to all of the bolt threads and under the bolt heads.  Torque the bolts in three distinct steps following the factory torque sequence; arbitrarily ~60%, then 85%, then 100%.  Pull s-l-o-w and steady on the torque wrench at 85+%.  Pull 100% a second time through on all of the bolts in sequence.  If using aluminum cylinder heads, tighten the head bolts to the torque recommended by the head manufacturer.  Let the engine rest overnight and recheck the bolt torque.  Typically, the intake gaskets will relax and the manifold bolts will require retorquing.

[LTZ C20]

All but the endmost intake manifold bolt holes open into the valley and are exposed to oil splash.  All of the head bolt holes open into the block water jackets and are exposed to coolant.  Chase all of the bolt hole threads then rinse them thoroughly with Berryman's B12 or similar - blow dry with compressed air.  If reusing head bolts DO NOT chase the bolt threads - use a wire wheel instead - even better, use new ARP bolts.  Apply ARP PTFE Thread Sealant, P/N 100-9904 to all of the bolt threads and under the bolt heads.

THIS is the information I was hoping for! Excellent, thank you BD. I knew the second half of what you said already, but which bolts need sealant and which sealant to use I did not know.

All of the holes for the head bolts are clean already and I'm reusing my ARP bolts. I have the torque numbers on the spec sheet that came with the heads for both the head and intake bolts.

[LTZ C20]

My local O'Reilly's carries this ARP 100-9909. Would it be a suitable lubricant also? They don't carry the 100-9904 PTFE lube. Would GM PTFE lube be suitable as well? If so I can get the GM stuff from work. I plan on doing the heads and intake tonight and fixing the timing cover.

[enaberif]

The reason you need thread sealant on the  head bolts is they pass into coolant passage and you'll get seepage otherwise. Also yes a little amount of oil on the bottom of the bolt flange so it doesn't bind when torquing.

This is the stuff I use and a little goes a long ways... http://www.amazon.com/Loctite-37615-Thread-Sealant-Stick/dp/B0015PJCHG

[bd]

ARP 100-9909 is strictly a torquing compound.  It dramatically reduces thread friction.  So much so, that recommended torque values usually require modification to prevent fastener damage or clamping distortion.  I use Ultra-Torque a lot.  But, Ultra-Torque is not a sealant.

Any good Teflon paste sealant should seal the bolt threads (e.g., Loctite, 3M, GM, etc).  PTFE sealant also lubricates the threads to reduce torquing friction, just not as much as Ultra-Torque.

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And, don't forget to correct that cam timing before you button it up.  You should have no problem aligning those timing marks.

[bd]

BTW - It is prudent to check intake bolt protrusion past the intake gasket sealing flange to verify bolt penetration into the cylinder head.  Threads in aluminum heads are less forgiving than iron and will pull more easily.  Aluminum manifolds typically have a thicker flange than the factory iron.  Hence, the standard SBC 1.25" UHL intake bolts may not provide enough thread engagement to clamp the manifold w/o shearing the threads cut into the cylinder heads.  Now would be a good time to select the intake bolts for maximum thread engagement, especially where the bolts pass through brackets.  For reference, BBC intake bolts are 1.5" UHL.  Choosing an appropriate length bolt now is far easier than Heli-Coiling the head down the road.

[LTZ C20]

Cool thanks alot guys. I'm gonna see if we got some GM stuff here at work that has PTFE in it. Also, my intake bolts are ARP, they put good distance into the head and I don't have any brackets for them to pass thru, just the intake itself.

I'll be sure to adjust the crank gear also, thanks for catching that.