Here is mine. Centered on the valve stem.

Nice work "Ford428CJ". I build race V-Twins that use shaft mounted rockers. By using special fixtures to figure stem length and rocker height this work takes time to figure out for sure, but is well worth not having possible issues with spring failure and guide/valve wear. A properly setup rocker geo also doesn't require roller rockers. In Harley world a stock hardened rocker arm has less deflection than a roller that is not hardened.

Quote from: gordonr390 on May 18, 2016, 06:54:00 PM

I don't agree on the burn time analogy either. I run a 99% factory stock/original 69 S code and decided to change up the timing advance to manifold vacuum months ago. When I discovered my factory advance was leaking I picked up a Standard pn#VC31 unit to give it a try while I figured out where to send my factory unit for refurb. I set the max timing @ 36* and at idle it settled down to 22*.  Drivability dramatically changed for the better. The car definitely is no horsepower king but the engine liked it and became more of a joy to drive. Fuel has changed sense 1969 and by running 92 octane now I felt it was a no brainer to try.

If you are happy with what you have, then it's all good.  However, I would say that you'd likely be even happier with a mechanical curve that did almost the same thing at low RPM.  What happens with your setup is that if you drop the hammer, the advance goes away.  If you had a bit more initial, a quick curve, and ported you'd have the same part throttle effects and the proper curve would be present when you went to zero vacuum

That being said, I am sure it's better than the stock slow and late timing curve, so is it worth recurving on a stocker?  Maybe not, I would, but again, if you are happy, that's the key and my guess is that yours IS significantly better than the stock curve, especially part throttle and low RPM

I agree. By having an aggressive curve on initial with the mechanical and a ported vacuum advance bringing up the the big end it would have more power. But I believe this engine is finished by 4500 rpm and could be almost hobbyish to pursue. I have top end set setup in the pipeline and will be using the setup you are describing when I go to assembly.

I bought The HPC a few years ago as well as Jay Brown's recently and I got what i paid for. Good information. The idea of copying anyones book either to make a profit and or screw the author out of his due so others can get it on the cheap doesn't sit well with me. I have spent $thousands on failed projects over the years in figuring out on what doesn't work, so If I can buy information that saves me dozen's of hours of time or even thousands of dollars I will gladly pay the man or group that did the research for it. JMhO

I found this video on youtube from a guy thats apparently has been doing the mod for a long time.   https://youtu.be/k6j1JuccvhQ

     "I'm leaning on the Idea of filling the exhaust heat riser ports on 1-4-5-8 only and leaving ports 2-7 alone". Any thoughts? This car is a weekend driver with 90k on it.
(I don't know what was going through my head but It seems I'm really having a hard time remembering this engine is water cooled. I appreciate and respect you all for not busting me about my dumb mistake).

I came across another stock manifold and would like to have it extrude honed.  Can enough material be removed to get close to the port entrance sizing of the head? Any recommends on a service company that can do the job?

   I'm hoping to get some time this weekend to make up some fixtures for my flow bench and really get going on this project. All of my fixtures are for Harleys. 
 

After determining a rusted no#7 intake valve causing 80% leak down. I pulled the heads this past weekend and decided to clean them up and box-em. I found a another matching set of C8AE-H castings from a head porter friend as I'm wanting to keep this motor appearing accurate but would like to make a little more power. So he found a set of custom Ferrea 26* 2.095 intakes locally cheap. Installed, cut the seat to 45* and cut the bowl then blended. Now were setting at a 90% choke (better than the 93.2% in stock config with the 2.030's) and these are the numbers so far @28".

.100   74
.200   167
.300   217
.400   222
.500   246
.550   256

Haven't tackled the exhaust yet. But I see major issues with 3 of the 4 ports having heat risers exiting to the intake and killing exhaust port speed. Talked with Alex at Alex's Parts today and he commented that some old timers had poured aluminum in to seal up the heat riser exits and then blended the ports. I was interested in finding out if anyone has performed this mod and how it worked out?

If it doesn't make sense then it probably isn't right to begin with. I got around to retesting my engine miss issue again today at home and away from the shop. And discovered why my leak down was so perfect.




I had mixed my compression tool accessories with my my leak down tester. So now the test shows number 7 intake is leaking bad and 5 has ring\wall issues. Oh the joy of buying someone else's problems. Thanks for all the input

I have a belief that most all these issues stem from a plenum being under sized. Plenums should be the same size in cubic inches as the engine it sits on or even larger. There has to be a reserve capacity sitting in the plenum to fill the requirements of a given engine. So in the end there is only one cylinder filling and firing at a time so having to mount large carbs to gain more power makes me suspect. 

My 2 cents. I don't see how a smaller valve in an FE would do much unless the entire port was reshaped, among other things. 

On the legendary C302A-B-C series of SBF heads, Ford made 3 what of I'll term major versions and a very few more with minor reshaping. One head having the smallest exhaust port volume apparently was tested with a less than the norm 1.60 valve. Yet, this post Trans-Am (re: Boss 302) head still reverted to the standard sized valve as the port was so good it more or less required a larger valve.  Interesting too that Pro Stock crowd learned long ago that shrinking the exhaust to allow a bigger intake was the way to go.

In both case though the heads for these race engines were optimized for port location, height and shape to maximize hp. FE heads, "as is" were not and even the famed Hi-Riser and Tunnel Port heads retained pretty much the same port shape, height and volume as many more run-of-the mill heads and all retained the more standard exhaust valve size. I still wonder why the HR and TP heads didn't receive some serious exhaust side port work from the Ford engineering folks.

So many variables not even related to valve size exist makes me think it would take some long and serious experimentation to the basic FE exhaust port in order to bring about some serious hp gains. Ford learned this with the prototype 427 SOHC that had the D-shaped port exit turned 180 degrees from the much more powerful final version. And yes, the interior of that prototype port has a bad dog-leg bend that was also taken out of the final product so it was an all-hands effort to maximize flow.     

It would be fascinating to see a FE head with say a BBC style exhaust port or better, a raised and re-shaped port also eliminating the R-L-L-R orientation of the ports as viewed from the top of a head. Ford essentially did this with the A-460 and B-460 race heads (essentially a BBC port) while Blue Thunder did the same but took it a step even further. Maybe someday........

I lot of information there to digest. I assume on the Edelbrock head could be ordered with an unfinished exh port?