Pontiac 455 Engine Build

Main Block
Cylinder Heads
Intake Manifold
Rope Seal Tech Bulletin
Rotating Assy
Valve train
Final Assembly

The first picture on this page has to be of the Pontiac Engine "bible". Jim Hand's "How to build Max-Performance Pontiac V8's"
This book is great. If you are looking to build a Pontiac Engine you are crazy not to invest the $20. There are tons of practical tips, knowledge, and research presented in it. I cannot recommend this book enough. That and I don't think there are any other books available for building Pontiacs...

The stock engine for this car was a 2 barrel 350. That engine was pulled and installed in my brothers 69 bird after it's 400 spun a crank bearing. I got the pile of parts that was the 400 with the intention of someday building it to go in my car . It needed a crank of course, some rods, pistons, cam, yadda, yadda. A lot actually. I was planning on dropping in a small block chevy 350 because I have a nice one basically ready to drop in with the right bell housing for the muncie. But there was the whole "sticking a small block in a pontiac" thing. I thought it would not matter, because I have always believed in doing what you think is right, not what other people think. But that is not to say I did not wish for a nice Pontiac engine to come along to do it "right". The 400 I had just needed so much and as you likely know building a pontiac is easily double what it costs to build a small block.

Then along came a 1976 Pontiac Bonneville. Likely the single ugliest car I have ever seen in my life. Not that the model is particularly ugly, but this specific example of that model was the worst. I am not sure what was holding the car together. Possibly all the stickers plastered all over the dash. I kick myself still for not taking a picture of it before it headed off to the crusher after I pulled it's 455. I did not even really want it but my brother needed it gone out of his yard. It was a nice planter but they were going to move and the car needed to go. There were only two things worth keeping on the entire car when I got it: the engine short block and the front grill center for an unusual garage wall decoration. The heads were 6H's which are the hugest combustion chamber pontiac ever made (giving the big engine an anemic 7.6 cr) and they actually had some cracks in them anyway. The intake and carb were so choked back for the smog era they were good for nothing. But the block only needed to be bored 30 over because of a broken ring ridge and the crank was good. I kept the pontiac turbo 400 as well to maybe put out at a swap meet someday .

So I am building a 455. Had no intention of doing it, But I am. When the final tally ($$$) comes
in I will likely need a pacemaker installed or a new wife, but I am going to do it right and it is
going to run and look as good as a big 'ol Pontiac engine can. As they say, there is no
replacement for displacement and a 30 over 455 for 462 inches should be a pretty nice engine.
I purchased a set of 6x-8 heads which according to the book and some other sites I found online,
are pretty good heads. I also bought a set of 4x heads at the same time from the same fellow.
I got them both on Kijiji, which if you have not used it yet, is a Great site for local buying.
Very "ebay"-like but without the bidding crap. It just puts buyers in touch with sellers for no cost.
I also got a great set of hedman ceramic coated headers for a smokin good deal on the same site.

Pontiac 455 Engine Block Prep

the block after hot tanking and crack-checking at the machine shop.
The little N/C are a good thing. They mean No Cracks.

the Hand book says it is a good idea to remove the lifter galley flashing which
as you can see is plentiful.

So away it goes. The book also suggests smoothing the lifter galley area to help
oil drain back. So I did.

Another suggestion for safety is to tap the oil gallery holes at the front of the block.
The plugs that were in these holes were quite easy to pop out during block
disassembly so it seemed like a good suggestion.

the four little marks around the holes are where the regular press-fit plugs were
staked in position to help them stay.

there was a large flashing ridge on the front drivers side of the block that I cut down a bit as well.

Above: April 9, 09 got the block back from the machinist. Bored, Honed, Align Hone
Cam bearings installed.

Below is a shot of the infamous Pontiac hidden oil gallery plug. The Hand book
describes a commonly advised upgrade is to drill a .030 hole in this hidden threaded
plug before re-installation to aid in distributor gear oiling.

So where does one find a .030 drill bit on a Saturday when all the industrial supply
stores are closed? I looked on my little decimal drill size card and found there
are not even any common fractional, metric, number or letter drills that are .030.
And there sure was not any that small in my normal drill index. Then I spotted
this little welding tip cleaner I have had kicking around for close to 20 years and
never really used. I opened it up and sure enough there were a whole bunch of
tiny tip drills in it.

and wouldn't you know it? one of them was almost exactly .030"

and it even held it's edge long enough to drill the plug. My cordless drill almost
would not close enough to grab it and you have to be so careful with a bit this tiny.
One sneeze or cough and SNAP.

A little bit of Permatex thread sealant and a magnet on the end of the allen key
so the plug will not fall off as I lower it down into the hole.

the dab of red on the plug was just to make sure I did not get this plug mixed up
with the two for the front, which were not drilled.

My Machinist is a good guy and loaned me the proper tools to set my freeze
plugs in. I was going to make some up but these worked great and saved me some time.

the aluminum disc is for setting the steel back cam tunnel plug in.

here is the brass freeze plug set I purchased through my machinist. He
recommended using some Permatex Aviation Form-a-Gasket around the
inside edge of each frost plug hole as extra insurance. I happened to have
an old bottle of it kicking around, so I did it.

And here are the back plugs all set.

then I installed the threaded plugs in the front oil gallery holes. These had
previously been filled with regular soft plugs.

I ordered a special rope seal from Butler. I was not able to use one of the more
modern Viton type seals in my block becasuse it fell under the special requirements
as outlinesd on this rope seal tech bulletin my machinist came across.

Main Block
Cylinder Heads
Intake Manifold
Rope Seal Tech Bulletin
Rotating Assy
Valve train
Final Assembly


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