small block heads questions

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pat d

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im building a stoker motor and i have a set of x's and j's open chamber. My question is what type of pistons i should use,pop ups flat tops. I want to run high comp.i know the open chamber heads will kill the comp.if i switch to a different head later say [closed chamber] will i run into clearance issues
 
open X or J with a flat top coming to the top of the cylinder will not be low compression I cant tell you the numbers but you will be stuffing a lot of volume with a stroker build
 
also the stroker engine will have a larger total cylinder volume then a standard stroke small block..that will increase the compression also...

I would use flat tops...the large domes tend to cause problems in the combustion chambers also..
 
Look at a piston that is designed for a zero deck clearance/set up. Hypuer-U's are fine for street and mild racing. The problem here really isnt comp ratio, but head flow to feed the mill. What are the plans?

I ask because ported iron would be OK for a torque monster engine not really reving high or looking to pound out some nice power numbers. Stock X or J heads are a bit on the limiting side.
 
thanks for the reply. I have these heads right now and cant afford anything else stroker kit is going to put a small dent in my wallet so im trying to work with what i have but i want to plan ahead for a later head swap . i plan on putting in 2.08in and port/polish [mild].had these j's on my old 340 and i hit 6500rpms with no prob.and it was still pulling.i know that bigger cubes need more air but can these heads work or they going to hurt
 
They will work there just not gonna rev nowhere near 6500 like the 340. CR with zero decked flat tops and .04" gasket is 11:1 with 72cc chambers and 12.3:1 with 62cc chambers.
 
thanks 273 whats the diffrence or why run flat tops as opposed to domes
 
flat tops for a stroker are off the shelf pistons and will be lighter than domes,domes are probably a cu$tom piston for a stroker. you will have plenty of compression with flat tops on a 4" stroke engine.
 
Domes interfere with the combustion process it's best to get the CR you want with the least amount of dome possible flat top being the best.
 
thanks guys still learning trying to figure all this stuff out
 
Iv seen A 395 stroker with well built X heads run A 11.05 in A 73 cuda street legal
 
anybody have any proven power # for a 416 and combo of parts to use
 
hey anybody build a 416 with j heads what kind of power #s
 
My 414 stroker with ported J heads made 460hp and 510ft;lbs. Hope that's enough power to run high 11"s in a 3200lb Duster.
 
thanks srduster340 what kind of pistons and comp. do u have
 
Did you check the link in my last post? Its what your looking for. Im not trying to sell it, its already been sold. Just more for your info.
 
thanks MLR, sorry i missed that i thought that was a magnum head . Whats the diffrence between the 596s and the Js i have the 596 w/2.02s/1.60 and would be an advantage to go with a 2.08 intake+ more compression
 
These engines are not as bad as some when it comes to dome design. Valve angle has alot to do with it. Take a SBC with a 23* valve angle(pictured) as a example, although some early 340 race pistons approched this level. This is what happens when you get up into the 12,13,14 to 1 range and it can be intrusive to flame travel and a full burn for max power. Most engines like this have to advance the spark timing to get a full burn before the dome walls it off from the far side. Most builders i was associated with back in the day always prefered a flat top, and even a slight dish as the most efficient design.
 

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sorry MRL had it mixed up what size headers did u run that test with 1 3/4 or 1 5/8 also what are these rockers and why oil through the lifters
 
Our dyno headersa re 1 5/8 to 1 3/4. The rockers were Comp rollers. Hollow oil thru lifters are a lot lighter than the std soild Mopar lifters. Plus we can run a oil thru pushrod which allows use to get a little more oil at the rocker adjuster(high pressure point) and it keeps the pushrod full of oil. A pushrod full of oil has a lot less harmonics than a hollow pushrod with nothing in it.

Hit a metal tube with a hammer that has nothing in it, then fill it with water or oil or some other kind of liquid and hit it again. get the picture?

The 596 heads and the J heads are pretty much the same. I dont give a nod to either one. Going BIG on the intake valve is not your best bet. The port wont support the valve size. Keep it on the smaller side and it will run pretty good. We used a 1.94" on that 416.
 
Here's one I did a few years ago:
[ame="http://www.youtube.com/watch?v=j0q0FJW4LcU&feature=plcp"]422" - YouTube[/ame]

422" (.060 over 340 block)
ported 596 heads (similar to J,X, etc but with a better exh port)
16cc dished SRP forged pistons (owner wanted future growth for better heads)
9.8:1 static. Runs on pump 91 w/10% ethanol.
Crane hydraulic H-302-2 cam
Video shows Crosswind - that was replaced by an Air Gap after it was found to be porous. On plain street radial tires it pushes a 3800lbs Challenger with 3.23s to 12.80s 109mph and gets over 17mpg.

Edit - cam specs are 232/242 @ .050, .504/.528 lift. For a 4" engine this is almost an emissions cam that makes 450+ hp and huge torque.
 
thanks for getting back to me. ok this may seem like a stupid question are these lifters hydl. or they solid and how do they get oil to them.do u guys have a roller lifter/cam package what do they start at this is for a [la block].
 
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