Porting a Chy 340/360 head.

[coulterracn]

Gordon

Is your top angle 38* now? If so I would cut it with a 30* stone again to the outer edge of the 45* seat. Then I'd use a 15* angle to narrow the 30*.

Ray

[coulterracn]

After you grind the new 30* and 15* angles use 400 or 600 emery paper to remove the sharp edges at the different angles.

This will give you a rounded edge which helps airflow accross the seats.

I do this on all the edges when using stones to grind the angles.

Ray

[blaktopr]

[Flash]

[Flash]

Quote
OK, lets look at this. You unshrouded the valve, how much? Then you say you top cut it AFTER the 38?? or was the 38 to the chamber wall?Quote


by the way i was just kidding with yeah, for got to put this ofter the jinks coment.

I have the blue and used it with and old head gasket, marked how far i could go.
Happened to have a 90* stone the was perfect in diameter to
cut just inside of my scribed mark.
Then i cut a 52* into it and then a 38esh* into that.
Made a vary nice sweeping affect. that 38esh got 45* seat, and took it out! had to do a lot of grinding to get it out, or back to 45*

Quote
How did the new VJ effect the throat and the SSR???


I tried to touch up the 75* cut, but, it chattered and broke the stone :p

Quote
What is your current bottom cut? Is it blended or a sharp edge?

What is yor SSR shaped like at the apex? Flat, U shaped, what radius is the wall/floor transition have?Quote

Here is some picture of my port.......before i cut on it last night, that may help.

some how i mest up the quote thing. pictures are at the bottom now.
Quote
Only some guys like us here go that route. Others just leave it and say it flows X. It's easy for them. We do the hard part.
Quote

Yeah i could say good enough! after all even though i lost 36 cfm, I'm at my goal of 240......right!.................NOT!!!!! Got to go figure this out :;):

Whether you are telling me or sugesting to me, it all the same....... I Want to Here It!!!!!!








Here are a few more of the other side of the ssr



Fast wall and SSR

[blaktopr]

MY OPINION!!! First off, looks good, grinder control that is.

1. After the top cut it looks as if there are areas to blend from the top of the cut to the chamber without making it flat. I would work on blending that area with a cartridge roll. Rolling it out.

2. I dont have any luck with the SSR "rounded" like that. The sides pinch up the SSR to the middle floor. I am guessing you are around 425+ down the center of the apex but 320-310 on the radius corners pulling the probe toward the center. It is also written that air dont like to turn in a "circle". I would try to widen the floor over the SSR, reducing the radius there.

I like your port/chamber layout better than mine. If I get a chance later I will post a few pics with a flow test of one of my iron ports. Different makes, but I can try to tell you what I did with a pic and what the result was.

[blaktopr]

I read over at speedtalk about what others have to say. It seems with these early heads not able to really handle over .28 L/D ratios that everyone has a different way to do things. Thats why you must bite the bullet and learn. I took my SSR out wider instead of the cant/bias or nice radius on each side ((1/2 radius) because I needed the CSA (3 sq/in) in addition to the help to even out the speeds. Different for each head and app. If your flow didn't get higher than things may have stayed calm. Sometimes the port starts to get so good that it flows better but also increasing the speeds.

[blaktopr]

Here is a pic of the SSR. Creeping up on the width without laying back or lowering it. The low lift didn't suffer.

[Flash]

Well, top cut back to 30*/15* re test, not much change, and still sounds like screeching tires! Sooooo time to do some thing drastic

laid back the ssr, a lot. widened the wall to ssr, alot, on the fast wall.

Did you see it.

straightened the fast wall so there was a clean visible shot to the bowl.


did you see it!......No?

OK here is a clear picture of my big mistake!



will some two part epoxy fix this?????? or what do you recommended for my boob booo

[coulterracn]

There is a recent post on speedtalk about using epoxy to fill or repair a head. Actually there are two post. One on iron heads and the other on aluminum heads.

On small block Chevy heads there's water in that location. I remove just enough material to blend the transition from the push rod pinch to the bowl. I don't straighten this wall. The wall to straighten is the divider wall.

[Malvin]

Hi guys you can get this stuff & it will work to fill that hole you have there Buy ZSpar SplashZone (old KopCoat)
2-Part Black and Yellow = dark green color

from Reher-Morrison That should do a really good job of
filling in that hole you have there


Malvin

[Flash]

[coulterracn]

[Flash]

[Malvin]

Guys when using the ZSpar SplashZone you have to make sure
that the area you are going to use it in is really clean.

I have used this stuff in the passed it does work very good.

Malvin