Cylinder Heads

[QuickKafer]

As we all know, the HoresePower is in the heads!

My little 1776 needs to breathe more.  My stock non-ported heads are choking my engine.  I don't want to replace them with some all out race heads, because this is still my daily driver.  However, I need to upgrade with some sort of mild comprimise.  I don't want something that will drasticly change my fuel economy.  But I do want some more top end!

I have no real budget to do this, as all my money is wrapped up in my big 2275 right now.  Those heads are killer!  They're 44.5x37.5 valves and a sweet port job by Heads Up Performance.  I can't wait to build that thing.

But back to my street motor...  How many of you have taken a grinder to your heads?  I've got 4 engines and 2 cars.  I'm sure I could scrounge a set of cylinder heads.  And I've also got a set of ratio rockers too.

I'd love to see what I could pick up in performance by smoothing out the heads.

Post some pics of your cylinder heads.   Tell us about them... valve sizes, race or street, etc.

Scott Faivre

[Yoda]

why not have a work in progress ,source a spare pair of heads give it a good decoke on the intake side and a polish on the exhaust ports and see what the results are.Compaired to stock heads. Then open the ports to match the intake manifold and blend them in and open the exhaust to the headers,see what differance that makes. Just a thought .

[HOT_62]

There is my cylinder head.

40 x 35 valves and polish intake and exaust ports, compression ratio 14:1.

Regars,
Estevam

[admin]

Lots of compression in Brazil! 
How are you Estevam?

What model cylinder head did you use? 043?  Do you have pictures of your intake and exhaust ports?

Your Friend,

Scott Faivre

P.S.  How is your Bus?

[HOT_62]

Hi Scott!

I like compression ratio! My drag car will be 16 or more!

This head is a stock with modification, but, I will change the chamber to a new design semi-Hemi to use turbo.

My bus? Is ready to run!!! Look the picture!

your Friend,
Estevam

[admin]

I remember you telling me that you use high compression with the ethanol gasoline that your country produces.  That will be very nice with your turbo! 

The bus looks great!  Is the interior done?  I'd love to see some more pictures of it!  You should put up a post in the bus forums.    Not many people know that your bus is NOT a pre 1967 version!

Scott Faivre

[HOT_62]

No, the interior not is ready. Maybe in the next month... 

I will be post in the Bus section.... 

About the hight compression ratio, in the turbo engines this no good use a hight ratio... sometime any piston fly out the block.... 

Yor friend,
Estevam

[admin]

No, the interior not is ready. Maybe in the next month... 

I will be post in the Bus section.... 

About the hight compression ratio, in the turbo engines this no good use a hight ratio... sometime any piston fly out the block.... 

Yor friend,
Estevam

Cool!  I can't wait to see the pictures!  Does the dash board of your 73 look like the dash board of pre 67 bus from here in the states?

Here in the USA we set compression to 7:1 or 7.5:1 for turbo engines.  But if top quality race fuel is used, the compression ratio can be higher.  And with your ethanol, the engine runs cooler than with the our gasoline.  You get to win!

Your Friend,
Scott

[admin]

Here's an idea I came up with...

I'd like to take a set of used cylinder heads that are no longer good for use on a VW motor (Heads with missing fins, cracks in the chambers, etc.) and cut them up! 

What?  Why would I do that?!!!    I have a friend that has a waterjet cutting machine and I'd like to have him slice the heads in half with the center of the intake port being the line that they cut on.  I'd also like to take the 2nd head and have it cut along the center of the exhaust ports.  This would make a GREAT cross section for all of us to view while we try to port our own heads.  We'd be able to see the thicknesses of the area above the chamber, spark plug holes, valve guide bosses, etc.

So, I ask you my friends, any body got a set of crappy heads sitting in the corner of their garage that I could hack up in the name of science? 

I'm going to check the swap meet at Irwindale this weekend and see if I can find any junk heads.  But be prepared to take a look in your stashes of parts if I don't come away with anything.   

Thanks!
Scott Faivre

[Tom Simon]

The choke point is those tiny valves, you need a pro to fix that for you. "It's real easy to screw up a perfectly decent set of ports if a guy doesn't know what he is doing" says local head porter Paul Widger, a guy who has been porting V8 heads since 1982, has a flow bench in his home garage shop and knows how to build engines that put out some serious power. The same has been said to me by other vw head porters.

If you are patient and skilled, you can make some improvements, but you need machine work anyway (valves, cut for compression, etc). To me, porting heads to save money is like learning to cut hair... anyone can use scissors, it takes years to learn to cut hair well. You can learn to cut your own hair if you are skilled and patient, but at the same time, you can go to a pro for not that much money. I work with a guy that cuts his own hair with a Flo-bee (think Suck-Cut from the movie, Waynes World)  His hair looks like it, but he is happy. You can tell he cuts his own hair, bye the way.

 Assuming you could get all the ports real close to being the same, and improve port flow, the other big problem with home port jobs is you can screw up the sensative exhaust to intake ratio, which means the exhaust needs to flow a very specific ratio when compared to the intake port flow. It is realatively easy to increase the exhaust port flow too much, and screw up that ratio according to one well know vw head porter I've talked to.

My rule of thumb is that unless I am going the whole route, I will only match port the intakes, and blend out casting lines and very carefully blend in the seats.

BTW, you find butched heads at the Pomona swap meet all of the time. Be careful buying a second hand set of ported heads.