[PONTIAC LARRY]

I would leave it alone run Super, it will get better mpg with it and the higher TQ off idle requires less throttle to drive. A big help in driving these old 10:1 ish motors beside a good radiator with 160 stat is to not run any vacuum advance and just set mechanical total timing starting off at 32 degrees with lighter springs to where it may at a high idle at 950rpm say 18-20 degrees BTDC and the rest in by 2000-2500 its enough to idle good and have no part throttle pinging since your not using the vacuum which can cause that. Don't turn your Stallion into a Gelding before at least riding him a few times ! The 068 cam is gonna help you on this issue too.

[Engine-Ear]

I would leave the C.R. as is and install a water injection setup if you can't achieve a timing/performance compromise.

http://en.wikipedia.org/wiki/Water_i..._%28engines%29

You don't show where you are, but if it helps at all, I have been everyday-driving 389-powered Pontiacs in city-traffic since 1990...some in Dallas heat mostly in Wisconsin (which gets into the 80s between June and September).

Hope it helps.

[blueghoast]

I decided to leave the compression alone for better performance and gas mileage.
I'll try it without the vac-advance to.
What about the holes that go down into the exhaust valve stems, Should I plug those
with 1/8 pipe plugs. That's got to let a lot of dirt and grime into the valve stem area.
Sure do appreciate all the info on this. Thanks a bunch guy's.

GT.

[Bill Hanlon]

Originally Posted by blueghoast

What about the holes that go down into the exhaust valve stems, Should I plug those with 1/8 pipe plugs. That's got to let a lot of dirt and grime into the valve stem area.GT.

I thought the holes (if we are talking about the same ones) are to the intake valve stem area. I daily drove my '57 GMC (Pontiac) V8 for over 100K miles with no bad effects with the holes open. Here is a drawing from '57 GMC Maintenance Manual showing the hole (#10 valve guide vent) I am speaking of. Holes are MUCH smaller than 1/8 NPT. Probably closer to a #6 screw.
http://chevy.oldcarmanualproject.com...5559mm412.html

[Engine-Ear]

Originally Posted by blueghoast

What about the holes that go down into the exhaust valve stems, Should I plug those with 1/8 pipe plugs. That's got to let a lot of dirt and grime into the valve stem area. Sure do appreciate all the info on this. Thanks a bunch guy's.

Ooof. I have no clue what you're talking about.

[blueghoast]

Maybe it is the intake side. I never had a problem with my 55 either
So I'll leave it alone to.
Engine ear, They look like where the smog holes were for the California cars.
They go all the way through to the valve stem. Check out the drawing below.

GT.

[blueghoast]

It's coming together.
Here is some mock-up eye candy.
I've got to get the correct color also
Factory scripted valve covers if it shows up.

GT.

[Ben M.]

That's looking great. Seriously jealous!

[Bill Eveland]

Looks like it should be up and running in no time. Bill Hirsch Auto has the correct blue green paint in case you didn't know.

[Rocky 389]

Originally Posted by blueghoast

The main reason I put the harden seats in was for rust in the exhaust seats was so
bad that there wasn't much choice a couple of the intake seats had us wondering
but they came out ok. My machinist did a pretty nice job of blending. I'll go in and
do some final blending as I want to do a little bowl cleanup anyway. And I might
open up the chambers a little to as to lower compression a bit.

The cam specs are 112 LSA 212+224@50 on Dur. The lift with 1.5 rockers are
.450's+460's with seat pressure of 100-115.
It's a little more lift then I wanted but the rest of the numbers seem alright.
The cam is suppose to make good low end, good milage and idle smooth.
I think it will be alright.
And thanks for all the info and knowledge.

GT.

.
.
Might want to mock up one cylinder of the engine to check valve retainer/valve seal interference with that cam. I used an old chevy solid lifter for the test. I encountered interference using a .490 lift cam in my Pontiac engine. My seals are the PC umbrella style and may take up more room the the old original "O ring" style. I had to remove each intake valve retainer and grind off material from the bottoms of the retainer, taking care to leave enough to allow seating of the keepers. I now have a gap of about 0.050 between the retainer and seal with the valve open.
It's a good thing I checked because the bottom of the retainer would have beat the top of the valve seal to death, not to mention "bottoming out" problems with bent pushrods, lobe wear, borken rockers etc etc.
Stock pontiac cams were never much more than about 0.404 lift I'm told.

[Jack Gifford]

Originally Posted by Bill Eveland

... the correct blue green paint...

It sure doesn't have much blue- I always just called it dark green. You can see remnants of it on his block.

[Bill Eveland]

No it doesn't have much blue at all, that's just what Bill Hirsch had it listed as. I remember cleaning off my 287 and under the grime still had some original paint underneath.

[blueghoast]

I always called it army green, I know it sure is ugly!!!!!!!!!!!

GT.

[blueghoast]

All the wheel cylinders I ordered are wrong so I've got to send them back
Then reorder the correct ones. Maybe I'll get the rite ones this time From
Rock Auto. The ones they sent me don't have bolt holes to bolt them on.
They look like there rear G-Body wheel cyl. that have the hole in the top
of them instead of bolts. Will see what shows up this time.

GT.

[blueghoast]

Well work picked up again so money is starting to come in finaly.
I re-ordered the wheel cyl's can get the hard lines locally and
then I can get the brakes done and finaly get the motor in it.
Then maybe take the baby for a cruise, I'm getting in-patient and
realy want to drive it. I'll let ya know how it go's.

GT.

[littlelemans]

That's great news! It's gonna fire up and roll down the road after all these years!

[blueghoast]

I've been working on the 57 a little bit.
I got the rear brakes done, Wheel Cyl-Lines, I still have to replace the rear
flexible line yet.
I have the wheel cyl's and flex lines for the front now and have to replace
one short steel line. I'll keep plugging away at it.

GT.

[blueghoast]

I got my front wheels painted today.
I'll get some pics up tomorrow.
Brakes are done now it's time to consentrate getting the
motor finished and back in the car.

GT.

[blueghoast]

Well the colors a little bit dark.
I've still got to do the back wheels maybe I'll lighten the color a bit.
Here are a couple wheel pics.

GT.

[PONTIAC LARRY]

Burnout pics soon ?