Yikes, can't argue with that picture. Good to know about how the clearance changes with the advance. One of the tasks on the assembly list was to check the valve to piston clearance with clay. And that picture emphasizes the point!!
I should have mentioned the potential clearance issue with extra advance with those heads shaved so much. Paul's a good man. You won't go wrong listening to him. :TU: I know I learned plenty from him already. TA 212's intake lift will be .454 with 1.55:1 rockers, so shouldn't be a problem, but when in doubt, check it out. I'd say if you have plenty of clearance, install it at 8* advance. It'll work better that way even moreso with the stock valves and small diameter header primaries. You'll have gangster torque further down in the RPM band. Edit: this advice is antiquated and defunct. Not necessarily currently endorsed.
I did remind him about piston-valve clearance earlier on in the thread, but it's been a while back and I forgot about it. He said he's using 1.65:1 roller rockers too, so that'll make his valve lift a bit more. Best to check clearance at this point, even sitting .058 in the hole. What do you think? Either way, just check clearance and set your advance as close to 8* as you can get away with I'd say.
Pistons are .058 in the hole..........and yes, it's been recommended by you and other members that no matter what, always check the valve to piston clearance when changing cams, or other changes affecting the valve train geometry. Such as shaving heads......thanks! There's good stuff on this board............i never would have started this project but for knowledge here, and the encouragement, that gave me the confidence, and courage, to decide that "yeah Cal (my son), we can do this!" Thanks again
Yeah just check to be safe but worst case you could just add some slight valve reliefs in the pistons with a dremmel tool... I bet it will clear fine though no matter how the cam is degreed. The NHRA guys run pistons at zero deck and are not allowed valve reliefs, so I bet you have lots of clearance.
I showed the piston picture to indicate where the piston to valve issue is. This person checked the piston to valve clearance using clay and only looked at the clay thickness at the bottom of the dish. He didn't check the clay thickness at the edge of the dish. I prefer using a light spring and a dial indicator at the valve to check clearance. For pistons around 4.00" and steel rods .080" minimum clearance is sufficient. I still like use .100" minimum for margin just in case all cylinders are not the same. There were 2 occasions where I purposely advanced the cam as far as the intake valve clearance would let me. Both those cases involved turbocharged engines that had too much cam duration and spooling time against the torque converter was too long. The advanced cam helped alot. The drawback was when the engine was below cam where intake port velocity was low, having the intake valve open that early into the exhaust stroke allowed the exhaust gas to be pushed into the intake runner far enough to melt the plastic ends on the fuel injectors. With that much reversion there wasn't any torque below the start of the torque curve Paul
I had a good talk with Mr. Steve Caruso, set me on the right track with degreeing the cam. Thanks much Steve!!! I'll be ordering my degree wheel and dial indicator tomorrow.
Been a long time since an update here.......went bear hunting (no bear), deer hunting (Caleb took a 10pt 200lb) and since December it's not been above 30 degrees and frequently below zero..........anyway, I do have a question........ I was able to convert 8 of the (old) hyd lifters into solids with gorilla glue, so that I can degree the cam and check for the correct pushrod length. My question is: Can I lube the cam before I degree and measure for pushrod length? Or will the lube distort the readings and measurements? btw, here's a pic of Cal's buck.... http://www.v8buick.com/attachment.php?attachmentid=280791&d=1393883474&thumb=1&stc=1
Had a good weekend with the GS, finally warm enough to work in the garage, the kerosene heater went through a gallon and a half of fuel keeping warm. Yesterday i installed the Jegs degreeing kit, located top dead center, the degreed the new cam..........at 4 degrees advance (by lining up the dots on the timing gears), the specs were spot on with the cam card. This afternoon i installed the heads, rocker arms and lifters, and with an adjustable pushrod i measured for the correct length since i had the heads shaved .060 last fall (and the new cam). Ordering the new pushrods from TA in the morning............she's coming back together...........feels good.
Installed the rocker arm studs into the heads on Saturday...........no pushrods yet, supposed to be delivered this afternoon. Just as well, lost power over the weekend, would have been tough checking for valve/piston clearance by flashlight.
Received my new length pushrods yesterday...........the plan for this weekend is to check piston to valve clearance...woot!!!
Confiscated some modeling clay from the lady's craft supply........checked the valve to piston clearance on all pistons yesterday. Minimum clearance was .09375.........good to go. Starting the reassembly today!!!!!!!!
On Saturday we lubed the cam with the break-in paste, installed cam, timing gears and chain, fuel pump eccentric, cam gear for distributor and the oil slinger. Also installed the heads. day by day.............a little bit closer to start up.......
Question........the engine manual it refers to using "Perfect Seal" on the threads of the head bolts. Never heard of it before, is there a modern equivalent, such as non-hardening Permatex?
I use engine oil on threads. Mostly you need a lubercant more than a sealer.other wiser can chew up threads in block.
Thanks, good to know......oil is what I originally used, but I did pick up a tube of permatex thread sealer on the way home last night, applied it to the bolts of the pass head and torqued it down. Will redo the driver's head tomorrow. Thanks again!
You only need sealer on bolts that go through to the coolant passages,putting a lot of sealer or to much oil in a blind hole(a hole that doesn't go through to somewhere) can crack the block because liquid does not compress. When installing bolts in a blind hole,lightly oil the threads,DO NOT SQUIRT OIL IN THE HOLE,and a little bit of oil under the head of the bolt as well. Derek
Thanks Derek, when I originally oiled the bolts with a fingertip, I wiped the excess off. Also, when I applied the thread sealer to the bolts, I went 3/4's around one thread. Sound good?
