Heads ;)

Post by **Type 4 Unleashed** » Tue Jan 09, 2007 9:00 am

I've thought about the sharp bend, and thought about trying what they have done to the small block Chevy exh port, which have years on top of years of R & D and flow bech work, and that is to raise the exh port, but that part would be harder on a Type 4 head.

The benefit of the Chevy port I was looking at, was they had filled in the sharp bend from the seat and also raised it so the Chevy exh port looks like a D, with the flat side of the D, is where the sharp bend use-ta be.

Now the sharp bend is now a curve that some what matches the back side of the port.

Also, the Ford 351 Cleveland heads, they already had a raised port and it's big, and all they had to do was just fill in the bottom of the port to raise it into a D type port, to improve flow, and their was a large increase in flow when they did this.

Google some of the aftermarket head manufactures like Air Flow Research, Brodix, Canfield, this may give you an idea of what I am talking about. They have views of their ports, so maybe this will help.

So move the port forward like you are doing, then weld up the bottom to raise it, smooth out the bend, or you may be able to straighten it ?

jonas_linder · Post by **jonas_linder** » Tue Jan 09, 2007 12:47 pm

So it may not be clear for everyone what you are looking at.. so I borrowed a picture from another thread ( http://www.shoptalkforums.com/viewtopic ... 23&start=0 ) to try to show you.

The primary reason is the short radius. As you can see in this picture it is improved! Getting a more shallow angle of the port is just another nice effect from this

The new flange is also tilted as in the picture.

I hope Nate doesn't mind me borrowing his picture!

richard >> yes, that is exactly what I'm trying to do I'm not sure you noticed but there is a distinct D-shape of my port

Thanks for the tip about google words

I think you all got my wrong.. I'm not trying to do a straight pipe, I'm trying to improve the flow quality and therby getting more flow at the same cross area!

ps. that is a really good thread about the type4 head

ds.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Jan 09, 2007 1:18 pm

This is something that we have not had the time to experiment with, too many other things going on... BUT Len does have a prototype head already modified to do a similar arrangement with, its just been on the back burner for a couple of years

I also believe that he has a digitized version of it ready to be finally cnc'd..

The main benefit I see from this is the area under the seat that begins to droop with high EGT would be heaviliy strengthened thus helping with strength under the seat and that keeps the valve jobs living longer with higher EGT, especially under boost.

This aspect of head development is often overlooked by head porters, after you have seen valve jobs go away after EGT of 1350 or higher has been experienced you'll start to understand and see the things that impact that..

Good work Jonas, if you see the results i believe you will it might inspire us to finish what Len started long ago, it's slightly different than your set up and I think either way would work well.. I know that Len altered the fastener arrangement seriously

Post by **Piledriver** » Tue Jan 09, 2007 4:46 pm

Might consider reducing the cross section up in the port to an area < that of the valve curtain, then slowly opening up the cross section.

(credit:T.O.O.)

I suspect he matched the desired pk HP to the min cross section choke area.

BTW, the area past the restriction will have supersonic flo (deLaval nozzle), if the min. cross section has enough flow to go sonic.

The valve and seat will stay subsonic.

He seemed to have little tiny high ports that flowed real well.

jonas_linder · Post by **jonas_linder** » Wed Jan 10, 2007 4:56 am

MASSIVE TYPE IV wrote:This is something that we have not had the time to experiment with, too many other things going on... BUT Len does have a prototype head already modified to do a similar arrangement with, its just been on the back burner for a couple of years I also believe that he has a digitized version of it ready to be finally cnc'd..

The main benefit I see from this is the area under the seat that begins to droop with high EGT would be heaviliy strengthened thus helping with strength under the seat and that keeps the valve jobs living longer with higher EGT, especially under boost.

This aspect of head development is often overlooked by head porters, after you have seen valve jobs go away after EGT of 1350 or higher has been experienced you'll start to understand and see the things that impact that..

Good work Jonas, if you see the results i believe you will it might inspire us to finish what Len started long ago, it's slightly different than your set up and I think either way would work well.. I know that Len altered the fastener arrangement seriously

Yes, the lack material is one of the 'problem' with the type4 head!

We have a 5 axel CNC mill at school that I can use

Piledriver wrote:Might consider reducing the cross section up in the port to an area < that of the valve curtain, then slowly opening up the cross section.

(credit:T.O.O.)

I suspect he matched the desired pk HP to the min cross section choke area.

BTW, the area past the restriction will have supersonic flo (deLaval nozzle), if the min. cross section has enough flow to go sonic.

The valve and seat will stay subsonic.

He seemed to have little tiny high ports that flowed real well.

Can you please evolve, I'm not sure I understand you correctly?

T.O.O ?

dstar5000 · Post by **dstar5000** » Wed Jan 10, 2007 11:10 am

T.he O.ld O.ne

Larry Widmir

http://www.theoldone.com/articles/

Start at the bottom nad work your way up.
OF course go in order 1- 2- 3, you'll see what I mean.

I've know him since the early 70s.

I guess that makes me old too!

Don

Post by **Piledriver** » Wed Jan 10, 2007 11:26 am

Direct link to best text description:
http://www.theoldone.com/articles/The%5 ... ad%5F1999/

Somewhere I have a link to pics of his worked Boss 429 Pro Stock heads... the ex ports are ~ stock T1 ports at the exit. Maybe.

He called them peashooters.

speedy57tub · Post by **speedy57tub** » Wed Jan 10, 2007 12:40 pm

Looking at the cross-sectional view (Nate's), you loose about 33% of valve guide support. Be careful and reintroduce some added lateral support for the valve guides.

Svwerker · Post by **Svwerker** » Sat Jan 13, 2007 4:18 am

Kindergarten headportingservice or Wallece and Gromit goes hiperformance?

jonas_linder · Post by **jonas_linder** » Sat Jan 13, 2007 11:35 am

Svwerker wrote:Kindergarten headportingservice or Wallece and Gromit goes hiperformance?

I just love your comments

How are your car coming along?!

Wally · Post by **Wally** » Sat Jan 13, 2007 1:59 pm

Wel, he took almost 4 years to post his first post.
Is he always this slow?

jonas_linder · Post by **jonas_linder** » Sat Jan 13, 2007 5:22 pm

Wally wrote:Wel, he took almost 4 years to post his first post.
Is he always this slow?

Yes, but just as fun as slow

Svwerker · Post by **Svwerker** » Sun Jan 14, 2007 3:27 am

My english is so bad that it takes a long time to look every word up in an dictionary.

Post by **doc** » Sun Jan 14, 2007 5:15 am

But your English is mega better than our Swedish.

Your efforts are appreciated.

doc

jonas_linder · Post by **jonas_linder** » Sun Jan 14, 2007 8:19 am

Okay, some more work.. it's really hard to make a thin aluminum pipe with clay

The pushrod tubes will be much thinner and shouldn't interfear with the cooling anymore than the stock ones. They are blocking the flow betwenn the pushrodtube and the port though!

The port shouldn't be any wider then the stock width but will extend as high as the pushrod tube. The idéa is to let the pushrod tube and the port to share material to make room for the bigger port

Will there be heat issues ?

This is just an idéa