talking head's

[j par]

Soooo, here's the thing - 596heads 1.88-1.60 now 2.02's plus port job(picture of head with 2.02s cut but not ported yet). Was using 273 rockers. 564 gross lift with 1.5 to 1 rockers which the stock 273's may or may not be ? Along with the 2.02s I'd like to use 1.6 rockers.
410 stroker icon flat tops with valve reliefs .010 out of the hole. Cam card says 603 gross intake lift with 1.6's.
.026 lash.
Soooo, when I asked the very reputable machine shop about the original setup and pistons hitting valves Ted said I would have no problem with the big valve reliefs. When I took heads in for the 2.02s I had them do a spring bind check and there fine for the extra lift.
I'll obviously have to check clearances. The problem is it will be a few weeks before the heads are done and I can afford new rockers. I'm guessing buy a couple of hughes 1.6 rockers for testing purposes ?
Any educated guesses on the clearance outcomes ?
pictures of block are old ones.
View attachment 20141120_125419.jpg

View attachment 20150202_121611.jpg

View attachment 20160107_174958.jpg

 

[70aarcuda]

clearance?

will the 2.02 valves clear the valve notches on the KB pistons....Yes

 

[TrailBeast]

Not knowing the deck height and valve relief depth it would be impossible to guess wouldn't it?

I'm asking, because I might be missing something?

I went back and saw "010 out of the hole" but I still feel like I must be not seeing something.

 

[70aarcuda]

Ext. Valve Depth 0.232 Ext. Valve Dia. 1.720
Int. Relief Depth 0.243 Int. Relief Dia. 2.200

Right there on their website....

 

[RustyRatRod]

KB pistons have some of the most generous valve pockets I have ever seen. They would probably clear .800 plus lift.

Remember the duration is what's important with valve to piston clearance, not lift.

 

[70aarcuda]

piston to valve clearance is measured during the overlap period of the camshaft...exhaust closing...intake opens...both valves hanging around as the piston is near tdc....

 

[TrailBeast]

Ext. Valve Depth 0.232 Ext. Valve Dia. 1.720
Int. Relief Depth 0.243 Int. Relief Dia. 2.200

Right there on their website....

Ah, duh.

Thank you.

 

[Cope]

wow those are some sexy pistions!
short skirt?
Forged?

linky?

I dont want to derail this thread but will such a deep valve pocket affect flame travel in any real word way?

 

[j par]

Duration was in question - Oregon(orygun) cam grinding solid lifter cam #175 -
Duration@ 50 - in. 259 / exh. 267
Duration @ 20 - in. 294 / exh. 304
lobe sep. 107
lobe center - in.104 / exh. 110
lobe lift - in. 364 / exh. 377
1.5 rockers - in. .546 / exh. .566
1.6 rockers - in. .582 / exh. 603
lash - in. .26 / exh. .28

 

[j par]

wow those are some sexy pistions!
short skirt?
Forged?

linky?

I dont want to derail this thread but will such a deep valve pocket affect flame travel in any real word way?

1yes
2yez
3no-icon
4good question? Idn :glasses7:

 

[Cope]

linky=do you got a link to the pistion page?

 

[j par]

linky=do you got a link to the pistion page?

Aaaa, mine came in a stroker kit from JE-E-E-EGS.

 

[JBurch]

linky=do you got a link to the pistion page?

https://www.uempistons.com/

Here's a link to the UEM home page

 

[j par]

Well I called hughes and Dave answered. He was not discouraging me to check piston to valve clearance, but he was highly doubtful there would be a problem.
I asked him about the 1.6 rockers and he went on about geometry. He was very helpful and told me about tech links that I can't seem to find.
anyway, one thing at a time- get the dana done next weekend. Hopefully get head's back from machine shop the week after that. Then hopefully order 1.6 rockers. That's when I'll worry about making them fit.
really that's only the tip of the iceberg #-o

 

[moper]

#4 - No. Recessed features don't affect flame propogation in any meaningful way aside from adding space to the chamber volume. Technically the best-case would be just enough depth for your cam/combo. But given the possible combinations as a manufacturer it's better to just have them be deep.

 

[krazykuda]

Put some clay in there and check it... Better to know than to GUESS....

 

[j par]

#4 - No. Recessed features don't affect flame propogation in any meaningful way aside from adding space to the chamber volume. Technically the best-case would be just enough depth for your cam/combo. But given the possible combinations as a manufacturer it's better to just have them be deep.

Moper you have to type slower so I can understand what you saying..... #-o

 

[j par]

Put some clay in there and check it... Better to know than to GUESS....

The head gaskets are still lying on the motor and I can use those too mock the head up for checking. I will check. Is there a specific automotive clay for checking that? I used silly putty to check clearances inside the oil pan last year like the back of the high volume oil pump was very close to the oil pan.

 

[D-50394]

I used Silly Putty When I checked my clearance..

 

[j par]

Clearance Clarence- Rodger Rodger - let's just hope the s*** don't hit the fan !

 

[Ironmike]

Play Doh works good. Just oil it up so the valves don't stick to it. I guarantee you'll have a ton of clearance. Open chamber heads and flat tops....only .010 out. I'd check it anyhow just to know how much ya got. Never hurts. Just outta curiosity, what gasket thickness and chamber cc?

 

[j par]

Play Doh works good. Just oil it up so the valves don't stick to it. I guarantee you'll have a ton of clearance. Open chamber heads and flat tops....only .010 out. I'd check it anyhow just to know how much ya got. Never hurts. Just outta curiosity, what gasket thickness and chamber cc?

as far as chamber cc ? I've never checked, I have only speculated the 596heads are 68 to 72cc ?
Fel-pro .039 gaskets.

 

[moper]

Moper you have to type slower so I can understand what you saying..... #-o

My typing sucks...lol. You need to read up more.

What I said was, the valve cutouts are depressions in the surface of the piston. Flame propagation (meaning the spread of the flame kernel from the spark plug through the mixture and across the chamber) will not be drastically affected by a depression in the surface. But, the volume of that depression will add to the volume of the space that flame front has to fill, which slows down the spread, and delays the buildup of pressure in the cylinder to a small degree. It's the same affect of an open chamber head on the burn time and pressure peak.... Just on a smaller scale.
A dome, or raised structure, would impede the flame propagation.

Think of walking over a flat field that has two holes dug in it vs. walking across a flat field with a tall mound of dirt in the middle of it. In the first field you can jump over the holes, with little loss of momentum or delay. In the second field you have to climb over or go around the mound which takes energy, lengthens your path, and lengthens the amount of time it takes to go across it.

 

[70aarcuda]

Got a 360 .060 with pistons out of the deck about .018 with MP .026 head gaskets with eddy open chamber heads that have been cut .030. Cam is a Hughes 6064 with 1.6 rockers with gross lift around .630....

Engine has been running since 2006, in Vegas usually goes thru the traps around 6900 rpm and in Bakersfield hit about 7300 rpm in traps....

Don't see ya having is clearance problems....but it is your call...do what makes you sleep at night..lol

 

[j par]

My typing sucks...lol. You need to read up more.

What I said was, the valve cutouts are depressions in the surface of the piston. Flame propagation (meaning the spread of the flame kernel from the spark plug through the mixture and across the chamber) will not be drastically affected by a depression in the surface. But, the volume of that depression will add to the volume of the space that flame front has to fill, which slows down the spread, and delays the buildup of pressure in the cylinder to a small degree. It's the same affect of an open chamber head on the burn time and pressure peak.... Just on a smaller scale.
A dome, or raised structure, would impede the flame propagation.

Think of walking over a flat field that has two holes dug in it vs. walking across a flat field with a tall mound of dirt in the middle of it. In the first field you can jump over the holes, with little loss of momentum or delay. In the second field you have to climb over or go around the mound which takes energy, lengthens your path, and lengthens the amount of time it takes to go across it.

Your typing is fine, my comprehension sucks.
I'm not on your knowledge level of this stuff, but actually listening and learning and making mistakes to learn more.
thank you for "slow bussing" that for me, now I get what your saying...