What do you guys think of all the Tech articles in the recent issues of PHR?  

I THINK THEY SUCK!!


JK JK


Mr. Kimball.... PHR's Website would be nothing without you!


HAHA now get out of my cube!  

thank you for your support?    

Of course... anytime.


There good articles...When do we get to see your editorial skills grace the pagaes of PHR?  

Sadly i don't think i'll ever be a writer, too much to think about.  

well we wouldnt want you to over work yourself of anything  

of course not    

Thats the spirit!  

I always like the tech articles, especially the detailed items like Vizard's and any real cost information.  Costing the items lets me think things like "Damn, you guys spent waaay too much on fixing up a 70 Torino."  

Yeah, until you see it all added up like that you don't really realize just how much it cost to build up a car.  

Oh, I know what it costs.  I'm just saying -for me anyway- I would not have spent the amounts on certain items and would have obtained similar items in different ways.  But the PHR build DOES showcase certain mfg/advertiser products and that's good for the mag in the long run.  And provides decent tech notes that might apply in other ways.  

Hi,
I think that the September issue is a great combination of history & technical articles.

The Traco 434 is the first advanced combustion chamber 23-degree SBC I think you have run. It is great to see the results of the Engine Masters work getting pasted on.

I would like to suggest an engine project:

Engine Masters has shown that a small chamber head with a reverse dome piston can be very efficient. This configuration forms a compact combustion space with short distances from the plug to the far wall. This shape, combined with small squish distances for turbulence, takes less spark timing and has a low octane requirement.

My suggestion is to do a before and after dyno test of three related combustion shapes. Starting with a set of aftermarket heads with a thick deck, run a common chamber size with a flat top piston. For the second chamber shape, cut the head something like 0.100” and add a D-shaped dish to the piston. The third chamber shape could be a full dish with only an outer squish band. These configurations would have the same compression ratio & squish distance. You need to work with a head designer so the cut of the deck does not reduce the intake flow if you use a high valve angle head like a SBC.

The timing and mixture needs to be optimized for each configuration, as you would expect changes in the combustion time and the specific fuel consumption. I think what you would find is that the dish makes the best power at high rpm but is down on torque at low rpm. It would also need more timing. This guess is based on roomers from NASCAR.  The reverse dome engine seem to use less timing and have more low rpm turbulence so they have a broader torque range. I think Engine Masters has proven this. The flat top is probably in the middle.

The reason this is an important test is that many of your readers could use this information right now and it is not an expensive mod if you are building a new engine. If we can raise our compression ratios, both power and economy go up.

Thanks for your hard work,
Steve  

hmmmm sounds like an interesting idea for a tech article