Changing Intake ports to a D shape for better flow.

[Bewarethemoon]

I always look forward to reading all your posts Jack and can’t wait to attempt what you’re demonstrating here on my spare head (the one with the poor port work by a PO)

Sorry to hear about the Sciatica!

Daniel.

 

[spungle]

I wish you a fast and well recover! Take your time

 

[Bewarethemoon]

I just watched one of Hugh’s videos and it was of a motor that you worked the head for him.

Any idea what power that motor put out?

 

[Jack]

I just watched one of Hugh’s videos and it was of a motor that you worked the head for him.

Any idea what power that motor put out?

Other than dropping my D port head off to Hughs to copy, I had nothing do with any of the porting on that head, only the floor was modified and even that was not properly worked,not enough epoxy in the floor or the short turn ,no bowl work,no port work. I explained what needed to be done and his answer was,he had no patience for this type of porting and that it was good enough . Afterwards I found out the spigot manifold wasn't even modified,the motor sounded good and that's it.
You can not take short cuts with this type of porting or any porting for that fact, people hand over their hard earned money for services rendered and you better not short change them.
As for power out put, it would depend on the whole package and some dyno tuning but we'll all know sometime in March what this head is capable of delivering thanks to Chris.

 

[Jack]

I wish you a fast and well recover! Take your time

I've had this on going problem for about 6 years now, when the pain erupts I deal with it the best I can, always warm up throughly before doing squats , it bit me but Thank You!

 

[ReycleBill]

I've had this on going problem for about 6 years now, when the pain erupts I deal with it the best I can, always warm up throughly before doing squats , it bit me but Thank You!

Jack, hurry up and

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I sing this to myself every time my back goes out. Doesn't help but I keep trying to convince myself it will.

 

[Jack]

Jack, hurry up and

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I sing this to myself every time my back goes out. Doesn't help but I keep trying to convince myself it will.

That what my other half says when she wants to snuggle

 

[Jack]

well one done and one more to go in a couple days. Used 4 of the meshes with the last one for holding the epoxy in place,then in about a few hours
I'll pat the epoxy down more. It's a mess but it'll all clean up

 

[Jack]

Laid the last piece of mesh,which will cut out when filing the epoxy down

 

[Jack]

Showing how the port floor height has changed and the epoxy will be cut down to 0.130. That's it for a few days

 

[Jack]

The JB cured enough for me to rough out half the floor this morning and I have to say this floor turned out 10 times better that my original D port
which flowed exceptional well for what it was. The short turn on this port is much taller in the middle and corners, where as my original D port was
a little higher in the middle than a stock XS port and the corners where some what like the XS1 floor but had enough there to roll the short turn over.
This taller short turn in Chris's head will allow the flow momentum to increase it's speed and velocity entering the combustion and allow me to
alter the short turn radius biasing the flow even more.

 

[Jack]

Here's the short turn, rough stage still needs some profiling.

 

[Jack]

D port floor partially done, still needs a lot of work.

 

[ReycleBill]

Jack, I'm learning a lot from what you have been sharing in this thread. I doubt I'll ever be porting heads myself but with what you are teaching us here I'm able to continue researching so that I believe I will someday know what to expect from someone who ports heads.

 

[Jack]

Here's a link using the string method that I used in D porting the intakes years ago using a simple reversible flow shop vac ,this method will indicate the areas of turbulence in the ports which in most cases will be the guide ,guide boss,valve stem and short turn. In my case when I was struggling getting the flow #s up,I inserted a flat piece of aluminum on the floor with a roughed out short turn radius and you could hear immediately and feel with how the pull in the port increased and flow testing confirmed this increase. These XS intake ports are as straight forward as you can get and with a few under your belt,you'll achieve a better understanding what areas to work. For a back yard DIY hobby porter like myself this string method helped me tremendously.
http://diyporting.com/thread.html

 

[arcticXS]

Jack,
Will you be able to share flow (cfm) numbers for this head when you are finished with it? And maybe numbers from a stock head for comparison?

 

[Jim]

Here's a link using the string method that I used in D porting the intakes years ago using a simple reversible flow shop vac ,this method will indicate the areas of turbulence in the ports which in most cases will be the guide ,guide boss,valve stem and short turn. In my case when I was struggling getting the flow #s up,I inserted a flat piece of aluminum on the floor with a roughed out short turn radius and you could hear immediately and feel with how the pull in the port increased and flow testing confirmed this increase. These XS intake ports are as straight forward as you can get and with a few under your belt,you'll achieve a better understanding what areas to work. For a back yard DIY hobby porter like myself this string method helped me tremendously.
http://diyporting.com/thread.html

That's an excellent link Jack!! Tuft testing.... a tried and true flow visualization method still used in aviation even today.

 

[ReycleBill]

Here's a link using the string method that I used in D porting the intakes years ago using a simple reversible flow shop vac ,this method will indicate the areas of turbulence in the ports which in most cases will be the guide ,guide boss,valve stem and short turn. In my case when I was struggling getting the flow #s up,I inserted a flat piece of aluminum on the floor with a roughed out short turn radius and you could hear immediately and feel with how the pull in the port increased and flow testing confirmed this increase. These XS intake ports are as straight forward as you can get and with a few under your belt,you'll achieve a better understanding what areas to work. For a back yard DIY hobby porter like myself this string method helped me tremendously.
http://diyporting.com/thread.html

Strings, who knew? Strings and drops of oil are what we used to figure out the best places to put spoilers and air scoops on the bodies of cars.

 

[Bewarethemoon]

Here's a link using the string method that I used in D porting the intakes years ago using a simple reversible flow shop vac ,this method will indicate the areas of turbulence in the ports which in most cases will be the guide ,guide boss,valve stem and short turn. In my case when I was struggling getting the flow #s up,I inserted a flat piece of aluminum on the floor with a roughed out short turn radius and you could hear immediately and feel with how the pull in the port increased and flow testing confirmed this increase. These XS intake ports are as straight forward as you can get and with a few under your belt,you'll achieve a better understanding what areas to work. For a back yard DIY hobby porter like myself this string method helped me tremendously.
http://diyporting.com/thread.html

I love this! So simple! Such an ingenious way to be able to visualise what’s actually going on!

 

[arcticXS]

That's an excellent link Jack!! Tuft testing.... a tried and true flow visualization method still used in aviation even today

Similar arrangements are used on sailboats, to aid with sail trimming/tuning. Basically one tries to achieve laminar flow/avoid turbulence near the sail surfaces, so they "pull" as hard as possible.