Edelbrock heads.

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Thanks, but that does not say what you want to use the car/engine for, or what uses are the most important to you; that information is the first thing to know in offering suggestions.

So is it safe to say that you will mostly drag race this car? Or do you want to cruise some? I ask because if you have high CR with pop-up pistons, up in the 11:1 or higher range, you would need a big cam or better than pump gas, and neither of those are typically the best choices for extensive road cruising. Not every combination is good for every use.
 
I want to use it for cruising with a few trips to track. We do have some street racing going on here .
 
I am using the 587s for right now .i plan on going to the 60179 next year. What are your sugestions ?
 
That is all very good info; thanks. And now I see why this is in the 'Edelbrock heads' thread.

In my view.... if you don't want to put in pistons again when you go the the Edelbrock heads, then I would push towards some flat-top pistons. The 574's are open chamber heads and the Edelbrocks are closed chamber heads.

For pump gas, and the Edelbrocks AND with 93 octane pump gas and a lot of cruising, I personally would be staying at 10:1 to 10.5:1 SCR; this limit, and the closed chamber Edelbrock heads, point to flat tops, not domed pistons.

The higher SCR helps make useful torque at lower RPM's and widens the torque curve down low, all which makes day-to-day cruising fun a lot better. You can achieve the higher SCR with either engine, so your direction with the domes was basically right for the 574 open heads but they would not work long term with the Edelbrock heads as you would hit the heads or just have too high a CR for pump gas without going to super thick head gaskets or a huge cam which would suck at low RPM cruise.

Flat tops can be KB Hypereutectics (lightweight) or a variety of forged (Ross, Icon, etc.) or cast Sealed power types. The forged are the most durable. The ligher 'hypers' generally make it necessary to rebalance the crank, but you may be doing that anyway, and lighter parts takes some loading and stress off of the lower end.

The downside of the flat tops will make the CR lower for the 574 open chamber heads. Your rear gear is higher so that helps, but you can make up for it more by putting in smaller cam and just letting the revs and top end HP be a bit more limited 'til you change to the AL heads. (Though with your good breathing intake and exhuast parts, it will still rev pretty darned well.) Or, put in a higher stall TC BTW, rev it more when you start off.

BTW, I have not run any DCR calculations at this point with the flat-tops, 574 heads, and various cams to see where that ends up.

And one more thought: You might be able to get some 'flat domed' pistons (the KB243 hypers is one example) that will help keep the CR up with the 574 heads, and then take them out and machine the tops down some when you go to the Edelbrocks and have good SCR in both cases. Some research would be needed on the piston head thickness but I suspect it will work. And you can always vary the head gasket thickness, starting with thinner ones with the 574 head, and going thicker with the Edelbrocks.

If you select the parts right, then the Edelbrock setup will end up with what is called quench, which helps fight detonation and improves combustion efficiency.

Sorry if that is a lot of rambling info! Your planned change in heads got my head to spinning....LOL. It is an interesting problem.
 
Thanks for the feedback I was thinking the 60179 were open chambers which I could work out with the dome piston.
 
#60179 are "open chamber", at least that's what most people call them. They have a big round area machined for .060" piston clearance for the (stock) 340 pistons which have a .090-.100 positive deck height.
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So do you think I would be better off going with say 10.1 flat top with the 60179 change in the near future ?
 
IMO, a zero deck height piston and a closed chambered Edelbrock head with a good stout but still streetable cam is an excellent way to go. You can adjust the final compression ratio sum with head gasket thickness. The above suggestion I have run several times and I am building a 360 right now like this.

You can run a head gasket in the .035 (with good rods and bolts!) to .050 area with a cam in the 244* @.050 range. This is pump gas, 93.

My engine runs the .038 gasket and a 251* @ .050 cam.
On the wife's 360, it is a thicker gasket that looses the quench but the cam is small and gearing is 3.23. Huge room to grow.

If your going to run a dome and want to move away from stock iron heads, I suggest W2's well ported. The only 3 draw backs are heavy iron weight and expensive rocker arms & headers.
However, if your truly interested in making power, your going to pay a lot for headers anyway (TTI or Dougs) and the price difference in good rocker arms isnt horrible when you get to this level.
If your looking for upper 400 to 500+ hp, the above applies and cost differences are small between the gear.
 
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Ooops, my mistake..... I thought you just made a error when you listed 60179 and meant 60779....which is the 63 cc closed chamber type. So yes, you could run a piston like the KB243 or similar piston with no changes to that head or no milling on the piston top. But the 60179 is not 'open' quite as much as the stock type heads... those stock heads have a flat area that is typically about .090" deep. Maybe mill off the 574 heads .020" to .030" and the CR difference would not be so great when you change heads. Check on the spark plug side too for piston to head clearance.

It is my view that changing the pistons 2x is just a pain in the rear and certainly a chunk of extra $$... if you are going to do it carefully and measure and setup things properly, then it takes a fair amount of work, or more money to pay someone else to do it. The obvious question: Why not go straight to the Edelbrock heads now?

As noted above, the 60179 head even with a .028" thin head gasket loses the advantage of quench. You end up with .070" or more piston head to cylinder head gap, which is supposedly too large for effective quench action. I personally feel the addition of quench is a good design choice for keeping CR up with a smaller, torquier street cam while aiding to fend off detonation; that was the driving reason that we went with the 60779 heads.

As for domed pistons, do you have anything in particular in mind? I just don't see why the need to go with anything truly domed for mostly street use as the CR's typically will run too high for 93 pump gas, unless you run a fairly big cam.... which goes against low end torque, cruising, etc..

Do you have a particular ET or other performance goal for those times when you go to the strip? That may drive a few more parts decisions.

BTW, FWIW, the stock 340 pistons stick out of the block by .018", not .090-.100". The KB243's mimmick that .018" + deck height.
 
My mistake on that deck height. I remember measuring them about 7 years ago. I guess my memory isn't what it used to be!
 
Thanks everyone for the info. I will talk with my machine guy Monday. Domes may not be the way to go for future heads .
 
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