1970-472 rebuild with benefits

["Cadillac Kid" Greg Surfas 15364]

SORRY BIT OF CONFUSION. THE POST ABOVE IS THE CONTINUATION OF THIS THREAD.
THANKS
Greg Surfas

]One of the positive things I have been able to due during this "slowdown" is put together a 472 motor.  The motor itself had 103K miles an on tear down there was less than 0.001" wear in the cylinders. Crank was also pristine and everything else checked out pretty good.  My thought was to "Blueprint" the motor and add just a few things to improve the low speed (to 4800 RPM) power without going exotic.; The motor will retain a stock idle and will maintain stock rocker system.
Here are a couple of shots of the short block.  The heads are at the machine shop for valves and porting and that info will follow as soon as I have it.
Block info includes zero deck, moly rings standard bearings (rod, mains and cam.

["Cadillac Kid" Greg Surfas 15364]

Top photo is as I found the motor before I started the rebuild

[chrisntam]

What's it going in?

["Cadillac Kid" Greg Surfas 15364]

Chris,
I have no idea.  It is one of a "few" motors I'm building to have something "productive" to do.  It is going to idle like a stock motor and pull like a tractor. There will be no way to tell that anything has been done until you step on it. What we used to call a sleeper.

Greg Surfas

[hornetball]

What cam did you use?

["Cadillac Kid" Greg Surfas 15364]

Rick,
Going with a CadCo SS205H cam. Excellent idle and lots of bottom end torque and power.
Greg Surfas

["Cadillac Kid" Greg Surfas 15364]

Just got the (SS) valves, the springs and the cam. Time to get back to work. Stove valve
Are 2.02” intake 1.65” exhaust. Got 2.19 intakes and 1.90 exhaust. Going to see if and how much illl cut them down to compliment some mild port matching and porting.
Greg surfas

[Cadman-iac]

Greg,

  I'm guessing that you do your own porting.  If you don't mind a few questions, what areas of the combustion chamber do you modify, and is there much anyone can do to improve the chamber? Such as taking the sharp edges off? And is there any benefit to narrowing down the exhaust guide boss in the exhaust port, or is this just a waste of time and effort?
I need to do a set of heads for my 472, and am curious to know if it would be worth the investment.
Thanks for any advice you can offer, and good luck with your rebuild.  It sounds like it's going to be a bit of a monster.

Rick

["Cadillac Kid" Greg Surfas 15364]

Rick,
No I don't do my own porting. That is something I leave up to the experts who seem to work their black magic successfully.  The heads I have on my "race car" were done on a CNC machine by MTS using patterns that they developed and I picked up about 75HP.  The ones for this motor are going to be hand done by a local shop that specialize in racing engines.  The heads will be flow tested at each stage and I will post the results as well as pictures of the work being done.  Porting is not for the amateur in that it is VERY possible to end up with heads that flow less efficiently or are actually destroyed.
Greg Surfas

[Cadman-iac]

 Thanks Greg,  I appreciate your opinion. Not sure how I managed it, but I answered your reply on another thread,  oops!!
Anyway,  what I would like to know is, is there any sort of an industry standard pricing for a porting job, and I do realize that it all depends on the extent of the work, but say for example a mild port job, is there a range that it should fall into?
  Thanks again for your time and knowledge,  I do appreciate your input.

Rick

["Cadillac Kid" Greg Surfas 15364]

Rick,
Please forgive this long answer, but it seems to me to be the only way to answer your question effectively.  Port design and configuration was done in the engineering phase of the 472/500 inch motors to optimize low speed torque and smooth operation at all engine speeds.
When, as I am doing here substantial power increases without detrimental side effects are the goal it takes a lot of experience WORKING ON CADILLAC 472/500 MOTORS. That said, it leaves only a very few shops that even want to tackle the jobs.  You will note that even though there are at least 12 companies that produce aftermarket Chevrolet heads, there is only one doing heads for Cadillacs.
The range of costs, including valves, springs and port polishing and some modifications typically runs from about $1,000 to $2500.00. 
Again, for any head work to be effective it has to be done with the entire engine package (pistons, compression ratio, cam shaft, intake and carburetor ((or FI)) considered.
Just "bigger is better" does not apply here.
Greg Surfas

[Cadman-iac]

 Thank you Greg,
That's what I was needing to know. Gives me an idea of what not to now, unless I should win the lottery,  LOL!
So for a basically stock engine,  it's not really worth getting the heads ported, the stock heads will perform just fine I take it.

Rick

[The Tassie Devil(le)]

One simple porting task that can be done by anyone, and assists in performance is to simply, polish the inside surfaces of the Exhaust Ports, as the rough-cast of the factory allows faster carbon gathering on the sides.

Plus, I like to Port-match the intakes and the exhaust manifold to create a smooth flow.

Bruce.

["Cadillac Kid" Greg Surfas 15364]

Rick,
When my heads are done I'lll have flow bench testing results to give you a quantitative answer.  Porting and a good valve job WILL help performance of ANY motor.
Greg Surfas

[Cadman-iac]

 Yes, I would like to see the results from your heads Greg,  thank you.

And I definitely know that port matching is beneficial. Thanks Bruce.

Rick

["Cadillac Kid" Greg Surfas 15364]

Heads are in the shop and should have the results in a week or so.
Greg Surfas

[Roger Zimmermann]

What a difference!

[The Tassie Devil(le)]

Looks very similar to the heads on my 500 after the installation of larger valves, and a planing job.   Also decked the block as well.

Bruce.

[Cadman-iac]

Hey Bruce,

  I see you're up late as well. When you surfaced the heads and block, how much did you have removed,  and what did it do to your valve train? I know there's no adjustment to it, at least not on the stock rocker system anyway.  Did you run a reground cam, or use an adjustable rocker setup?

Rick

[The Tassie Devil(le)]

G'day Rick,

I am still up, but it is only 9.30pm Wednesday as I type this.

The Deck was decked to the height of the pistons, and the heads were planed as much as the technician thought best.   He had the crank, bearings, block, and assembled the pistons to the rods after a full balance job, and when assembling, I checked the distance of leakdown on the followers, and if I remember correctly, I shimmed the supports for correct geometry.   I used a MTS #10 Cam.

I would have liked Adjustable Rockers, but then I would have had to use aftermarket rocker covers.

Bruce.