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Posted by: 02loftsmoor Aug 20 2014, 06:03 PM

I'm following a guideline that Ray posted a while back on using 1.7 heads, opening up the exhaust valve to a 1.8 exhaust valve..and the port the hell out of the exhaust port. relocate the spark plug.
I need some guidance , pictures, measurements anything that could help me DYI port these heads. and I will say please and thank you, and will buy a beverage of your choice.

Posted by: Cap'n Krusty Aug 20 2014, 07:07 PM

Using your flow bench, determine the flow. Calculate the most effective flow rate for your C/R, camshaft, displacement, and intake/exhaust systems. Again using your flow bench to determine the changes as you go, remove material from the appropriate places until the desired port profile and flow rate are achieved for the RPM range you plan to use. It's that simple ......................

The Cap'n

Posted by: Jacob Aug 20 2014, 07:19 PM

Here is a site that tells you how to build a flow bench using a shop vac.
http://www.diyporting.com/flowbench.html

and here is a guy that produced a series of videos on how to build one.
https://www.youtube.com/watch?v=RNuVOB4-HuA

Posted by: 02loftsmoor Aug 20 2014, 08:27 PM

Cap'n your killing me, I'm just a poor service manger that has never built a T4, is there a simpler way? not wanting to build a fire breather on my first build.. I've been known to grenade an engine or two.

but that shop vac flow bench is cool

QUOTE(Cap'n Krusty @ Aug 20 2014, 08:07 PM)

Posted by: 396 Aug 20 2014, 08:36 PM

QUOTE(02loftsmoor @ Aug 20 2014, 07:27 PM)

Cap'n your killing me, I'm just a poor service manger that has never built a T4, is there a simpler way? not wanting to build a fire breather on my first build.. I've been known to grenade an engine or two.

but that shop vac flow bench is cool

QUOTE(Cap'n Krusty @ Aug 20 2014, 08:07 PM)

Using your flow bench, determine the flow. Calculate the most effective flow rate for your C/R, camshaft, displacement, and intake/exhaust systems. Again using your flow bench to determine the changes as you go, remove material from the appropriate places until the desired port profile and flow rate are achieved for the RPM range you plan to use. It's that simple ......................

The Cap'n

Posted by: 02loftsmoor Aug 20 2014, 08:43 PM

did you see what they want to do a port/polish,, OMG,, thats why i asked,, my MG's you could make a jig and you had to be careful of the water jacket . I'm looking for some sort of guild line to stay out of trouble..

Posted by: messix Aug 20 2014, 08:49 PM

some simple things are port match to intake and exhaust manifolds, remove casting flash, smooth valve bowl before valve seats install then smooth transition to valve seat.

a stock size street engine wont need/benefit from much extensive work.

Posted by: messix Aug 20 2014, 08:51 PM

QUOTE(02loftsmoor @ Aug 20 2014, 07:43 PM)

Posted by: 02loftsmoor Aug 20 2014, 08:54 PM

I have the bits to build 2056, correct me if I'm wrong on the displacement, needing advice on a cam. I have a set of Weber 40s.
I would like to keep the RPMs lower, Im wanting torque mid range punch

Posted by: r_towle Aug 20 2014, 08:55 PM

It's a weird shape in there so you cannot measure it with conventional tools.
A flow bench, homemade is really the best way to make sure you are doing the same thing to all four ports...

He may sound a bit sarcastic, but he is right on this one.

Read the shop design....build one of those.

Posted by: 02loftsmoor Aug 20 2014, 09:00 PM

my EST for European motor sports


Attached File(s)
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Posted by: 02loftsmoor Aug 20 2014, 09:01 PM

The Capt'n is a good guy, just a salty dog!!

Posted by: smokum Aug 20 2014, 09:15 PM

to say Shapping and porting is simple, is no diff than saying rebuilding a engine is simple. its just not true. IT is a science i did not have the time or space to do a flow bench properly so i found an engine builder that was willing to work with me as i made changes to my heads. I would grind and he would flow. it showed me were i made mistakes and gains.
David Vizard is the god of head porting he wrote the book! or books on it.
all our engines are the same internally let no one tell you differnt.

http://www.popularhotrodding.com/tech/0610phr_cylinder_head_porting/

http://www.popularhotrodding.com/enginemasters/articles/hardcore/0412em_porting_cylinder_heads/

Posted by: jasons Aug 20 2014, 09:49 PM

QUOTE(02loftsmoor @ Aug 20 2014, 08:00 PM)

Posted by: bdstone914 Aug 20 2014, 10:14 PM

I have a set if 2.0 heads that I just pulled off an engine today. I would sell them for $ 450 for the pair. You would just need a standard rebuild. I can get them blasted and inspected for damage if you are interested. You can expect to replace exhaust guides. I also have the cylinder tins.

Posted by: 02loftsmoor Aug 21 2014, 08:28 PM

QUOTE(bdstone914 @ Aug 20 2014, 11:14 PM)

Posted by: Jake Raby Aug 21 2014, 09:08 PM

Wow.

Posted by: draganc Aug 21 2014, 09:39 PM

QUOTE(Jake Raby @ Aug 21 2014, 08:08 PM)

Posted by: 02loftsmoor Aug 21 2014, 10:22 PM

tell us the skinny Ray

Posted by: 02loftsmoor Aug 21 2014, 10:25 PM

Sorry "Jake ""

Posted by: 02loftsmoor Aug 21 2014, 10:28 PM

Jake see what happens when there is know one to watch us,, keep the matches and Scissors put away

Posted by: Mark Henry Aug 22 2014, 06:06 AM

Peeps love to make things seem harder than they really are, a mild P&P is not rocket science. The big part is having a die grinder thin enough, long enough and the correct tools.

Unless you plan to totally alter the port shape you don't need a flowbench. Don't worry about the intake they are plenty big enough. Don't go crazy removing material and do not remove the guide bosses. The exhaust just clean up the flash and polish smooth. Experience and common sense helps.

BTW did the seats and P&P on my 44X38mm 2.0 heads for my engine, I've also used HAM heads (forget number, but one below the top) on almost the exact same engine combo. By the seat of my pants I could see no difference in power from to two builds. On a dyno I seriously doubt any more than a 10hp difference between the two engines and that could be chocked-up to just the different exhaust systems.

Also FYI the biggest single improvement you can make is the exhaust system.

Posted by: 02loftsmoor Aug 22 2014, 06:59 AM

Thanks Mark, just looking for some tips to stay out of trouble,, never did a type 4 so i will ask for help.

Posted by: Dave_Darling Aug 22 2014, 08:40 AM

Here's a tip: Don't touch the short radius of the exhaust port. Taking material off there doesn't help flow much if at all, and it takes material out of a part of the head that is a bit marginal in strength already.

--DD

Posted by: 02loftsmoor Aug 22 2014, 03:16 PM

QUOTE(Dave_Darling @ Aug 22 2014, 09:40 AM)

Posted by: Al Meredith Aug 22 2014, 05:28 PM

On the 1.7 heads I install a copper exhaust gasket and note the amount of meat arround the gasket. I'll bet I remove 10% of the opening to match the gasket. This only works on the 1.7 as there is plenty of excess alunimum in the exhaust stream,

Posted by: Dave_Darling Aug 22 2014, 05:37 PM

The port bends, right? At the valve the port is pointing more or less outward, and it bends to point downward. Because of the curve, one side of the port has a tight turn radius, and the other has a larger radius. Don't take material away from the side of the port that has the tight turn radius.

That's the part that is facing down when the head is mounted on the car.

Here's a picture of a 1.7 head cut straight through the port:



It's from this thread on Shoptalk: http://www.shoptalkforums.com/viewtopic.php?t=71523

The short-radius bend is the very short and kind of sharp bend visible at the bottom (toward the bottom of the photo) of the valve seat.

--DD

Posted by: 02loftsmoor Aug 22 2014, 09:46 PM

clear now,,, Thank you that's what I'm talking about!

it looks like you can't take much out any where

Posted by: Jake Raby Aug 23 2014, 12:40 PM

You'll need the flow bench to shops you that your first few sets of ported heads will flow less than stock.

And, of course its not just gross flow that counts, its mixture quality, so you'll need a pitot tube and a swirl meter, too.

And, then you always have to ensure the camshaft is optimized to the ports…

Then you'll have to play with port flow margins intake to exhaust.

Its fun. You'll love it. If you're lucky you'll get to do it everyday, but don't ever be dumb enough to start selling what you know.

Posted by: Dave_Darling Aug 23 2014, 01:10 PM

Remember that those are smog-port heads, so the port has the extra room for the air injectors, and the bosses for the injectors to come through.

The thread I linked has some pretty decent discussion of porting the Type IV cylinder head, though it is rather dated now. I suspect that it may be enough to give you an idea of some of the basics, but the current state of the art is well beyond that now. (Stuff happens in a decade where dedicated people are trying hard to improve things--who'd'a thunk it? )

Oh, and you might see some familiar names on that thread....

--DD

Posted by: ThePaintedMan Aug 23 2014, 01:11 PM

At some point, every "car guy" learns to specialize in what they themselves know. Engines, transmission and installing glass are just a few things that I leave to the pros like Jake, Len, McMark, etc. Eventually you realize that the costs in tooling and time are not worth it - you'll never get it back. I will eventually rebuild a Type 4 for my own understanding, but I'll never get the HP out of it that those guys do. Sometimes it's better to just spend the $ and trust that you're not being . They're good peoples.

Posted by: colingreene Aug 23 2014, 04:08 PM

Ive flow benched my stock 2.0 heads after seeing the data i opted not to touch them for reliability sake
Also add to the fact that they flow pretty damn well.
Plus you are building a 2056 right? Its not a huge jump in displacement
Id recommend you leave them alone.
a good valve job is going to do more for you than anything else.

Posted by: 02loftsmoor Aug 23 2014, 06:33 PM

guys thank you for the input, I think I'll leave it to the pros, I do have a set of 2.0 Porsche heads that need repaired, have said that I have the extra set of 1.7 heads to fiddle with,, flow bench your getting out of my league, I don't know what I'm looking for, and the expense for a one or two time job is not worth it,,

All and all you guys did give me a direction to move to, and I thank you..

Now what lift and duration cam do I need to buy for a 2056cc, 2.0 heads, 40 webbers.

looking for mid-range power

Posted by: colingreene Aug 24 2014, 09:19 PM

give web cam a call and as a few questions would be where id start.

Posted by: Jake Raby Aug 24 2014, 09:33 PM

Keep in mind that cam grinders know their product very well… But they are not head porters or engine builders… They are usually among the least effective people to recommend a cam, UNLESS they have data to work from, like actual port flow.

Debbie is no longer at Web Cam, that chick was the T4 specialist there, no one knew more about the T4 cams than she did, other than Steve, the Owner.

Posted by: 02loftsmoor Aug 24 2014, 10:09 PM

I will take the tips to heart thank you

Posted by: stugray Aug 24 2014, 11:08 PM

A webcam 86b is not overly aggressive for the street and works well with carbs.

Their description of it: Strong mid and upper end performance for small displacement racing engines.

Will require setting of the valve geometry but nothing to worry about in the valve to piston clearance dept on stock parts and stock deck height.

Posted by: HAM Inc Aug 25 2014, 01:07 PM

If I spend 10 minutes on a 1.7 ex port I will need to spend around 40 minutes on the intake port to keep a 75% ex/in flow ratio.

On a 2.0 914 10 minutes on the ex port requires about 20 minutes on the intake.

YMMV