Picture of 340/360 head porting....Mistakes?

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I guess the biggest thing is to change my mind set.............I know how a" port window" should look........But every time i see one, all i want to do is smooth up and round everything to make it follow up the ssr turn.
I need to let the "wall" air and the ssr air travel into the bowl not up the ssr. (Trying to get as much of the air, as possible to run up the ssr to the seat......is a bad thing......but i keep doing it:BangHead:)

Why! I say i need to change my mind set is that, my "mind set" says that Sharp Edges are a NO NO!!!! The more round, like a pipe, you can make a turn the better it will hold on or keep air attached to it.
Well if you put a finger on the ssr of a stockport(from the floor side).......well it's like a pipe that you have Stepped On! Not a smooth radius round section of a pipe........I need to except that this is ok.
 
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Here is a pic of a cut up intake port that shows the stock SSR in its stock forum.
Also make you realise how easy it is to find water!!!!!!

SSR.PNG
 
Cudafever said:
Here is a pic of a cut up intake port that shows the stock SSR in its stock forum.
Also make you realise how easy it is to find water!!!!!!

View attachment 1715475933
Click to expand...
I sure would like to see that pic without the match book. Great thread. I'm starting to understand. I assume SSR is short for short TURN radius as its called in the diagram. Great thread though a little confusing. Might rename it 50 reasons to buy aftermarket heads. LOL
 
There is nothing to see. that is prp and the port curves and the saw blade cut the port out.
I will give you the other side of the port in a minute.
 
If the floor didn’t have water under it, you could make the floor lower with an even much longer radius.

That’s the “laying it back”.
Starting from the bowl side, and angling the floor back towards the intake surface.

With these heads...... when you go too far, you hit water.
But from a flow standpoint, that’s what works for me.

The X head short turn is laid back more to start with than the later heads....... which is why they’re easier to get into the 270+ range with just normal porting.
The floor is better.
 
PRH said:
If the floor didn’t have water under it, you could make the floor lower with an even much longer radius.

That’s the “laying it back”.
Starting from the bowl side, and angling the floor back towards the intake surface.

With these heads...... when you go too far, you hit water.
But from a flow standpoint, that’s what works for me.

The X head short turn is laid back more to start with than the later heads....... which is why they’re easier to get into the 270+ range with just normal porting.
The floor is better.
Click to expand...
You are saying that the X DID flow better than the J ?
 
On my bench, an ootb X head is better than an ootb J head 90+% of the time.

They start out better, and with the same effort applied to both, they end up better....... at least that’s how it works out when I do them.
It’s strictly because of the shape of the floor, and what you can do without fear of hitting water.

The X head only came on 340’s..... which means it only came on a HP factory engine...... and it only came with 2.02 intake valves.
So, the shape of the floor was designed for that sized valve...... and the bowl to accommodate it.

The J head was designed to be able to accommodate either a 2.02 valve...... or a 1.88.
There aren’t 2 different castings for the two different valve sizes....... it’s one casting machined two different ways.
Which means they had to add enough material to the floor in the area of the short turn to make it usable with the smaller valve.
The approach from the floor into the bowl on a J with a 1.88 valve is pretty similar to the X with the 2.02.
When you add the 2.02 to the J, a lot of material gets removed from the bowl at the short turn, which makes the transition from the floor into the bowl more “stood up” and abrupt.

When you compare an X to a 2.02 J, the floor of the X appears noticeably “layed back”, and you’d have to do a fair bit of grinding to the floor on a stock 2.02 J to get the same form as the ootb X.
 
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