1978 360

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superdave

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Hi there!
I have just bought a 78 360 from a fellow...
It included a separate balanced bottom end with kb190 pistons.
On The KB website it says you can't used edelbrock heads with these pistons.
Does anyone know why and what heads would work best?
I want to make approx 400 horsepower.
Will the stock 78 heads do it with porting?
Thanks!
Dave
 
I'd assume it's because the KB190's stick out of the block too much. I can see not being able to run them with closed chambered Eddy's but I know they make a Eddy head specifically for a 340 which had it's pistons sticking out a little bit. Nevertheless you can easily make 400 hp with stock iron heads especially since you'll have pretty high compression with those pistons. It shouldn't take much more than a mild clean up and good valve job along with a properly selected cam, intake, carb and headers to get 400 hp. There are several good guys that do it and one here on the board is BJR racing. If I'm not mistaken he says it's possible with the small valves the 360 heads have. You might try a search for him and see what he has to say. His names Bobby.
 
It can be easily done as I'm very close to what he wants out of his engine to the ground with a 318 and 318 heads. So a 360 better do it with ease.
 
Those pistons are full chamber quench. They have a raised area (like a flat top) that is .050 taller than the blueprint deck height. First, you need to know where teh pistons are in terms of that block. If the block wasnt square decked or blueprinted, they will be "in the hole" by a little bit. If they were set up right, they need a big chamber for any pump gas mild combo. They show 10.9:1 static with a 68cc head.. (that's an open chamber factory head with nail head valves and some milling...) So I would be cautious as to what you do to the heads. Also, to run a quench design engine with factory chambers... they need to be equalized in volume and depth FIRST. Then you can set the dome height of the piston either by milling the pistons (KB says to do it that way) or square decking the block. Building aquench design with open chamber heads is a PITA. Like BJR said...For 400hp, you dont need quench, or porting. But you do want a low enough static compression to not detonate.
 
I don't understand what quench is...
Can someone explain?
What about using magnum heads?
Thanks!!
Dave
 
Quench is the amount of "Squish" area between the head and piston. It also has to do with the distance between the 2 as well.

You can not use Magnum heads.
 
so can you or can you not use them with eddy heads..im concerned now because that is the set up with eddy 6017 heads witch are the 340 heads with 65 cc combustion chamber
that i have and there are no clearance issues turns over buy hand just fine pistons do not it the heads so i should be ok right?
 
JimmyV said:
so can you or can you not use them with eddy heads..im concerned now because that is the set up with eddy 6017 heads witch are the 340 heads with 65 cc combustion chamber
that i have and there are no clearance issues turns over buy hand just fine pistons do not it the heads so i should be ok right?
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According to Edelbrocks website the 60179 head (I assume you mean 60179 as that's the only Edelbrock Chrysler head part number that starts with 6017) is
Designed for non-emission 1968-73 340 c.i.d. Chryslers, RPM Chrysler 340 heads have chambers machined .060" for clearance with early high-compression engines
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Their reference to early high compression engines can only be the early 340's that had the pistons sticking out of the hole. Should be fine but don't take my word for it. Check it somehow. On a buddies 340 we checked his by setting the head down on the assembled block without the head gasket in place and rolled the engine over. It didn't hit so we knew we had at least .050" clearance cause that's how thick the gasket was.
 
fishy68 said:
On a buddies 340 we checked his by setting the head down on the assembled block without the head gasket in place and rolled the engine over. It didn't hit so we knew we had at least .050" clearance cause that's how thick the gasket was.
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LOL, good move. Creative thinking on a problem solveing move.


Jimmiy, I assume your running the KB190's?
 
yes with the eddy heads 60179 and its all assembled with head gaskets and it rotates over buy hand fine no interferance
 
fishy68 said:
According to Edelbrocks website the 60179 head (I assume you mean 60179 as that's the only Edelbrock Chrysler head part number that starts with 6017) is Their reference to early high compression engines can only be the early 340's that had the pistons sticking out of the hole. Should be fine but don't take my word for it. Check it somehow. On a buddies 340 we checked his by setting the head down on the assembled block without the head gasket in place and rolled the engine over. It didn't hit so we knew we had at least .050" clearance cause that's how thick the gasket was.
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I AM PLANING ON DOING THAT SEEMS THE EASIEST WAY TO DO IT AND A LITTLE EASIER THEN MEASUREING CLAY
 
Ok So I Got Home Tonight Pulled The Head Now The Kb Pistons Dome Sticks Up 0.050 The Edelbrock Heads Are Machined With A 0.060 Clearance For The Early High Compression 34os The Head Gaskets I Have Compresed Measure 0.038 So That Is A Total Of 0.098 Of Clearance Subtract The Piston Dome Of 0.050 That Is 0.038 What Do You Guys Thing About That Sound Right?? Seems To Me This Is A Roundabout Way Of Measureing With Out The Use Of Clay..let Me Know
 
fishy68 said:
According to Edelbrocks website the 60179 head (I assume you mean 60179 as that's the only Edelbrock Chrysler head part number that starts with 6017) is Their reference to early high compression engines can only be the early 340's that had the pistons sticking out of the hole. Should be fine but don't take my word for it. Check it somehow. On a buddies 340 we checked his by setting the head down on the assembled block without the head gasket in place and rolled the engine over. It didn't hit so we knew we had at least .050" clearance cause that's how thick the gasket was.
Click to expand...

JUST WENT OUT AND PULLED THE HEAD REMOVED THE GASKET PUT HEAD ON NO BOLTS AND ROTATED #1 BACK AND FORTH BETWEEN TDC AND NO NOISE AND HEAD DID NOT MOVE UP IN ANY WAY
 
To me it sounds ok but I know some get squeamish when the clearance is less than .040". But I also have read guys building engines as tight as .030" when everything is machined properly. So who you gonna believe!!
 
fishy68 said:
To me it sounds ok but I know some get squeamish when the clearance is less than .040". But I also have read guys building engines as tight as .030" when everything is machined properly. So who you gonna believe!!
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it seems ok to me too.. i am still thinking about calying just to tripple verify and if that checks out ok im going to run with it... honestly you never know for sure until you fire it up
 
I agree with ya there fishy. Good machining, accurate measureing on the machiest and your own behalf with quality parts should get you through.

Rod strech is an issue that should be considered. Alot of people will not calc this in and steer clear of super tight clearances. Better to error on the side of caution than have a big boo boo!
 
I'm running a non stroked 78 360 with J- style heads, M/P rods, 11.0-1 M/P pistons, cast crank.
Puts out just shy of 450 horse.
 
Hey Spaz, what exact pistons are you running?

Those MP rods are very good rods. 4340 I think.
 
rumblefish360 said:
Hey Spaz, what exact pistons are you running?

Those MP rods are very good rods. 4340 I think.
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All the engine builder told me was they are MP forged pistons, but I never did get a parts list breakdown on all the part #'s.

I have also had some people tell me there is no way a non stroker can make that horsepower, but why would the guy lie to me, and I have the dyno sheets with 8 pulls.
 
They don't beil;eve ya...good, wipe there ***' clean off the slate when you run it. 450 isn't like this crazy number, LOL! Sheeezzzz. Some people!
 
rumblefish360 said:
I agree with ya there fishy. Good machining, accurate measureing on the machiest and your own behalf with quality parts should get you through.

Rod strech is an issue that should be considered. Alot of people will not calc this in and steer clear of super tight clearances. Better to error on the side of caution than have a big boo boo!
Click to expand...

That's right. Rod stretch is often overlooked. That's why I'm building my new stroker with .040" quench. Better safe than sorry and my lucks usually sorry. LOL

cudaspaz said:
All the engine builder told me was they are MP forged pistons, but I never did get a parts list breakdown on all the part #'s.

I have also had some people tell me there is no way a non stroker can make that horsepower, but why would the guy lie to me, and I have the dyno sheets with 8 pulls.
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Say what? They don't believe a 360 can put down 450 hp? If the heads are done up right they'll do that with stock iron heads.
 
Yes, the heads are fully ported and the intake matched nicely.

This baby likes to breathe and really opens up after 4500 rpm.
 
fishy68 said:
That's right. Rod stretch is often overlooked. That's why I'm building my new stroker with .040" quench. Better safe than sorry and my lucks usually sorry. LOL
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I don't remember what I learn years back on what metals stretch more than others. I remember when I built my last 360, the Edelbrocks closed chambers and a zero deck KB-107 with the Fel-Pro .039 gasket looked real good on paper. So I gave it a shot to see how it performed. And preety nice considering the mild purple cam @ 292/.509. It propeled the 73 4spd Cuda well w/4.10's.
It was a very nice street combo.

Say what? They don't believe a 360 can put down 450 hp? If the heads are done up right they'll do that with stock iron heads.
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That's the thing. A well preped set of iron heads can flow right around what Edelbrock has on paper to what there heads flow. A nice fat curve with the valve rise. It doesn't even have to be great past .500 Just great until .500 is all that you'll need for a nice machine. (Though more the merry in some case's)

Reminds me of the time I put a smack down on a Nova talking loads of junk on my crap iron heads.

Lets face it. It's not rocket science. Just a well put togther engine with a decent parts seclection and gears. You'll go!
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