1974 455 Rebuild

Well, I finished my project a couple of days ago. Took just over 4 weeks to go through the engine and transmission. I had a local shop do the tranny,
and I had a Stage 2 shift kit installed along with an Allison 18-2100 stall converter. They said the transmission had some sludge in it and third gear was about gone, but no metal shavings to speak of. (My '74 TA has 69,400 original miles on it.) Inside the engine, I found the #4 connecting rod bearing to be a little rough, but the crank only had a couple of very minor scatches on it so only needed polishing. The cylinder bores had very little wear and only needed honed. I built the engine myself. I installed a Melling high volume oil pump, Comp Cams 268 Extreme Energy cam with lifters, and a high volume water pump. I put my 4X heads aside for storage, and had a set of 1978 6X #4 heads rebuilt with new guides, hardened seats, new springs and BB Chevy rocker studs. I have Hooker Competition headers and Flowmaster 2 1/2" dual exhaust to finish it off. The biggest pain in the ass in the rebuild had to be putting the headers back on. Hopefully I will never have to mess with them again.
After my initial cam break-in, I took it for a short easy drive. Doesn't take much throttle to get the old girl moving now! After that drive, I found I had an oil leak at the back of the engine. I could only think that I had screwed up the rope seal, and that meant a major pain to repair. Upon closer inspection, I found that the leak was from the back of the oil pan. I had to drop the pan, (all of 1 inch), and replace the gaskets. I found the the rear neoprene seal had split lengthwise about an inch at the bottom of the rear main. I can only guess that I had snugged all the pan bolts down, then tightened the bolts at the timing chain cover, which pulled the pan forward and stretched the rear seal. I took it for another short drive after replacing the pan gaskets, and no more leak.
I plan on taking it out to the drag strip sometime this summer after I put a few hundred miles on it. I will let you all know then how much of an improvement I got for all my work. My total cost for the engine and transmission rebuilds was right at $3,000, and numerous cuts and scrapes on my hands and arms. ;^) Here's some links to a few pictures.
HD
http://webpages.charter.net/gallen541/Engine%20Before.jpg
http://webpages.charter.net/gallen541/Engine%20After.jpg
http://webpages.charter.net/gallen541/Engine%20After1.jpg
http://webpages.charter.net/gallen541/TA10.jpg
(hope these work!)
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That last link doesn't seem to work. Let's try this one. Just a picture of my car.
http://webpages.charter.net/gallen541/TA10.JPG
HD
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I had the same problem with my friends '74 T/A. Everything went well but a leak at the back of the engine showed up. I pulled the engine again and installed new oil pan gaskets and installed the rubber seal around the main cap dry this time around. Seems to have a much tighter fit. Maybe I'll get everything back together tomorrow and see if I still have a leak(I better NOT!!) Pontiac had problems with the three finger seal which is why it was only around for a couple years. They blow out easily from crankcase pressure.
Watch that rear rope seal on your engine. Due to federal regulations the new ones don't have an asbestos core and don't last very long. Its causing a BIG PROBLEM with engines that use rope seals. I went with a BOP Engineering viton rear main seal that is made for Pontiacs.
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Dennis Smith
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I was just looking at the picture of the engine in the car. The vacuum lines don't look right. There isn't suppose to be a rubber line running down the drivers side. Its attached to the port on the carb for the charcoal canister. The TVS on intake has a rubber line on the top port which is for the vacuum door in the air cleaner. I got a '74 vacuum routing diagram I can e-mail if you need it.
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says...

lines
the
canister.
vacuum
if
Dennis, That vacuum line you are referring to goes to the vacuum advance on the distributor. That is how it has been routed since I got the car in 1980. I will check the vacuum line routing again. I have the factory service manual. Is the diagram in the manual? I would look now, but am on my way out the door to work. :^( HD
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The vacuum diagram is in the '74 Emissions Service and Diagnostic book which is separate from the normal service manual. There is also a diagram in the Pontiac master parts book that the dealership parts department used.
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which
the
Dennis, I did find the emission control diagram in the factory service manual, (section 6D), and it is also in the emissions control pamphlet that is in the glove box. (I was lucky that all of the original paper work and manuals were left in the glove box. I even have the original warranty with the buyers name and address on it, along with the dealers name, address and date of sale.) I will probably leave the lines hooked up the way they are now for awhile, and put them back to factory configuration at a later date and see if there is a noticeable change in idle or performance. Thanks for the heads up on this. HD
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The way you have it hooked up now is how it was pre-emissions days which is more geared towards performance anyway. The way the '74 was set up is to only provide vacuum advance when the engine was warmed up and in high gear or overheated.
Its kind of neat how it works. When the engine is cooled off some but still warm and started it idles right around 1000 RPM until the 30 second delay relay on the firewall closes and then it goes down to normal idle speed. Its almost like its computer controlled. High tech, 1970's style!
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HoDad wrote:

<snip of majority of post>
Now that you Got-R-Done (lol), and spring has aravied. You should go out and rack up some miles, burn a little rubber, maybe hit the drag strip.
Beleave me, there is nothing better then a clean car, with a freash driveline on a summers evening after a hard days work. Especially for crusin home in. Gets you there in a better mood. Charles
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Damn straight, Charles! And I'll be grinning all the way!!
HD
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