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-   -   Cylinder Head Porting - INFO please. (http://www.hotrodders.com/forum/cylinder-head-porting-info-please-196930.html)

vk-v8 04-21-2011 10:28 PM

Cylinder Head Porting - INFO please.
 
Hello,

I am about to Port my Cylinder heads on my 304 V8, and the intake manifold.
I have a Air compressor and a Air die grinder.

Now all I need it a the Porting Kit. What is everything that I need?

What carbide burs do I need?
What Sanding bits do I need?
What polishing bits do I need?

Where can I buy a kit from? I am in Australia BTW..
Do I need the Carbide bur or can I just use the sand paper?
Do I need to polish it after?

Thanks!

my87Z 04-22-2011 09:00 AM

my advise would be to buy this book first, i know it's not for the AMC 304 but it should still have the same concepts to help you along



http://www.amazon.com/High-Performan...5&sr=1-1-fkmr1

cobalt327 04-22-2011 10:53 AM

Quote:

Originally Posted by vk-v8
Hello,

I am about to Port my Cylinder heads on my 304 V8, and the intake manifold.
I have a Air compressor and a Air die grinder.

Now all I need it a the Porting Kit. What is everything that I need?

What carbide burs do I need?
What Sanding bits do I need?
What polishing bits do I need?

Where can I buy a kit from? I am in Australia BTW..
Do I need the Carbide bur or can I just use the sand paper?
Do I need to polish it after?

Thanks!

Welcome aboard.

My understanding of the 304 leads me to believe the head has an almost ideal cross sectional area for the valves it comes with. What this means in terms of porting the heads, is you need not remove any large amount of material to get good results. This also means that you likely do not need any carbide cutters, period. Instead, I would plan on using sanding rolls (both tapered and straight) and you need not go any finer than 80 grit- this means you do not need to polish the ports, especially not on the intake side. If you wanted, you could go to a finer finish on the exhaust side, but IMO it's really not necessary.

I would concentrate on smoothing and removing any casting "flash" or irregularities, and on the valve seat to bowl transition- there is almost always a pronounced lip created by the machining of the seat. Avoid hitting the seats w/the tooling you use! If you do any work to the combustion chamber, use old valves to protect the seats. Then streamline the shape around the valve guide, but do not shorten it. Be sure the intake-to-head port openings are in alignment, but do not "bell mouth" the ports to make this happen, as is often the case when "gasket matching" is done. That only serves to disrupt the flow as it hits the bulge- which slows the flow velocity- and stacks up the flow behind it, creating less rather than more flow. There are tutorials here and elsewhere (use the search function) that shows how to properly mate the two openings w/o creating any unnecessary bulge.

If this is not news to you, disregard it- there's a large variation in experience among the membership here, and there's no way to know offhand what you come into this with, experience-wise.

Good luck.

Bad66 04-22-2011 12:20 PM

Yeah he said it all. You can watch some vids on youtube also. JMO, if it's your first time I would stay away from the carbide burs. These badboys take alot of material off real quick (the pros use them to speed up the job). Porting is a much bigger job than most people think, and you can really mess up your heads if you haven't done your homework. Also, remember that any material you take out of the combustion bowl can affect your compression ratio. Good luck and have lot's of patience

cobalt327 04-22-2011 12:59 PM

A three angle valve job along w/the seat-to-bowl transition smoothing will be the bulk of the easy to do improvements. If the valves have a wide enough margin (this can be a problem when reusing old valves) you can see if they'll take a 30 back cut- this will help flow. If the valves are new there will be no problem retaining enough margin.

Using larger diameter valves than the stock 1.787" x 1.406" can be done- but if you do use larger valves from the 360 or 360 heads w/2.025" x 1.625" valves, the results may be less than expected (if they fit, period!) because of the close proximity of the valves to the 3-3/4" diameter cylinder bore. Some builders will opt for the Chevy valves (1.94" max intake, 1.55 for exhaust).

Seems the '70- '73 non bridged rocker heads are preferred. The '68-'69 exhaust ports were the rectangular-type and used different diameter head bolts. Heads newer than '73 had paired rockers.

ap72 04-22-2011 07:56 PM

A 3/8" cylinder with a rounded or bull nose double cut carbide can greatly speed things up, then clean it up with 60 grit cartridge rolls, its all you need.

Ohio-Dan 04-23-2011 06:06 AM

Being from Australia, I would think he was talking about a Holden 304.....

68NovaSS 04-23-2011 10:33 AM

Quote:

Originally Posted by vk-v8
Now all I need it a the Porting Kit. What is everything that I need?

Where can I buy a kit from? I am in Australia BTW..

Thanks!

Here are some of the tools you asked about.

vk-v8 04-24-2011 02:06 AM

Heya!
 
Hello,

I am from Australia.
I have a Holden 304 5L.
Today a managed to pull the engine out.
How do you Undo the Flywheel bolts?
The nut heads are so short.... I need to undo that before I can get it on the engine stand!.

What are the next steps?

Have a look at some photos!

http://i232.photobucket.com/albums/e...o/IMGP1677.jpg

http://i232.photobucket.com/albums/e...o/PIC_1741.jpg

http://i232.photobucket.com/albums/e...o/PIC_1775.jpg

God or bad?
http://i232.photobucket.com/albums/e...o/PIC_1782.jpg

http://i232.photobucket.com/albums/e...o/PIC_1785.jpg

vk-v8 05-16-2011 02:29 AM

Porting
 
Hey Guys,

Where can I get a good Porting Kit?

What porting tools do I need?

I need to start on the port job ASAP!

Please let me know!

cobalt327 05-16-2011 05:58 AM

Quote:

Originally Posted by vk-v8
Hey Guys,

Where can I get a good Porting Kit?

What porting tools do I need?

I need to start on the port job ASAP!

Please let me know!

You may be better off sourcing your abrasives and mandrels, etc. locally. Find a machine shop supply house that sells abrasives and get a selection of "tootsie rolls", both straight and tapered and about 80 grit. These fit onto a mandrel that's chucked into whatever tool (electric or pneumatic) that you're working with- so match the mandrel diameter to the tool.

If you have large amounts of material to remove, you'll want to use stones or a carbide cutter. They come in various sizes and shapes, I use a ball and tear drop-shaped tools for what little work I do w/carbide. Stones come in a verity of shapes, grits and materials- some are better w/iron and some better w/aluminum. Since I don't use stones per se, I won't comment further regarding them. I prefer to use the cartridge rolls as much as possible because for me they just do a smoother, better job but they are slower than a carbide tipped tool, that's for sure.

There are flapper wheels to do finish work with, but again- I prefer to use rolls for most all the work I do. For working w/aluminum, I use the double cut burrs and keep them clean by lubing them often. Single cut carbide cuts too aggressively for my liking, YMMV.

BOBCRMAN@aol.com 05-16-2011 05:56 PM

Better have that flywheel re-faced or replaced. There are heat checks and it looks badly worn. Heat checks lead to cracks. Not good on a stick hi-perf car.

cpankey226 05-16-2011 07:50 PM

Quote:

Originally Posted by vk-v8
Hello,

I am from Australia.
I have a Holden 304 5L.
Today a managed to pull the engine out.
How do you Undo the Flywheel bolts?
The nut heads are so short.... I need to undo that before I can get it on the engine stand!.

What are the next steps?

Have a look at some photos!

http://i232.photobucket.com/albums/e...o/IMGP1677.jpg

http://i232.photobucket.com/albums/e...o/PIC_1741.jpg

http://i232.photobucket.com/albums/e...o/PIC_1775.jpg

God or bad?
http://i232.photobucket.com/albums/e...o/PIC_1782.jpg

http://i232.photobucket.com/albums/e...o/PIC_1785.jpg

nice ride would you have any idea how a fellow could get the hemi dodge six cylinder engine from over there into the states?


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