OST-030: a case in point

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oldeskewltoy
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OST-030: a case in point

Postby oldeskewltoy » Wed Apr 08, 2015 9:19 am

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Got this via FedEx yesterday....

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I've gotten heads in all kinds of containers/packaging. But this one is unique, and lead to the title..... :)

It has very interesting latches....

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I wish all clients would be able to do this.......

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Safe and secure with plenty of protection around it

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the head is clean, and it comes with all the hardware....

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..... along with a set of Pon cams!!!!



More to come....... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

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86_LeViN
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Re: OST-030: a case in point

Postby 86_LeViN » Thu Apr 09, 2015 8:11 am

hmmm...military owner by any chance?...we use those cases for equipment/parts

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Thu Apr 09, 2015 10:56 am

86_LeViN wrote:hmmm...military owner by any chance?...we use those cases for equipment/parts

from another forum wrote:That's a flight case, often used by musicians and such.
The latches are very similar to those used in Military cases (non Peli type) as they have a high latch strength and low profile :)


Now I (we all) know about this kind of case/latch 8-)


While OST-031 is being cleaned and pressure checked, it gives me a few days to work on OST-030...


Besides the Poncams, my client is using a piston with a 3.2cc dome. He has to check, but believes he has .005" of positive deck - piston slightly ABOVE the blocks surface. He wants to run a squish of .040".

What chamber volume does he need for a 11.3 to 1 compression ratio?


My clients said his head had been already run through the mill once... .008"

Image


Seems pretty close to me....

btw... look at the "round" exhaust port... :roll:


All the cam journals look pretty much the same as this...
Image

Since MR2tailbreaker noticed a "small" problem in his cam and journal clearances using the Poncams, I'll be checking these journals for similar issues.....


Work begins on the bowls and seats of chamber #1

Image


More to come.... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Fri Apr 10, 2015 11:13 am

from another forum wrote:What do you do about bad cam journals and caps?


not ignoring you... not quite ready yet to show that part of the process :)

from another forum wrote:Is this a CA customer? 11.3 on 91 octane, better have clean chambers, and management dialed in nicely, my recommendation from experience... I would even worry that improved breathing/VE would skew things even more toward a little less CR. If this is 93 octane, probably it's fine, but potentially close to incipient detonation.


Other side of the country..... Part of the issue is opening the chamber to accommodate the piston. With the clients deck, and the piston volume, the chambers may need to be "opened".


Most pistons can be milled a few ten thousandths, which could drop the piston volume under 3cc

example of piston milling
Image

The piston I designed could be milled .030" and drop the dome volume from 2.5cc to about 1.8cc.
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Fri Apr 10, 2015 3:56 pm

#1 is almost finished...

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Here is #1 exhaust bowls/port in transition

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And a closer view of the short radius, and the port in the background

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More to come....... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Mon Apr 13, 2015 4:12 pm

2 down.... 2 to go.....

Chambers.....
Image



exhaust ports.....
Image



More to come....... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Tue Apr 14, 2015 3:14 pm

further progress... 3 down 1 to go....


this time the intake view - first short radii...
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followed by the view down the ports
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The exhaust...
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And the chambers... 3 panel this time so you can see the progression

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More to come..... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Wed Apr 15, 2015 5:49 pm

4 down......

Image



Image


Next stop valve job and resurface... and then we set chamber volume....




More to come....... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

trigun402
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Re: OST-030: a case in point

Postby trigun402 » Thu Apr 16, 2015 5:48 am

Always amazed with your work.

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Thu Apr 16, 2015 3:35 pm

trigun402 wrote:Always amazed with your work.



thanks.......... ;)

oldeskewltoy wrote:
Besides the Poncams, my client is using a piston with a 3.2cc dome. He has to check, but believes he has .005" of positive deck - piston slightly ABOVE the blocks surface. He wants to run a squish of .040".

What chamber volume does he need for a 11.3 to 1 compression ratio?


My clients said his head had been already run through the mill once... .008"



Here is what is now known....

82mm bore or 3.229"
77mm stroke or 3.031
.012" piston sticks out of the bore
.052" Cometic gasket
3.2cc piston dome

So I ask again what chamber volume does this build need to have a static CR of 11.3 to 1???

Now how do I achieve that target volume on a head already cut .008", and will be cut an additional .002"????
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Fri Apr 17, 2015 9:02 am

from another forum wrote:If all else remains the same and assuming the bore of the head gasket is 1mm larger than the cylinder bore then you need a volume of 37cc.

I should have had you answer these other responses :)

from another forum wrote:Without checking it..

stroke volume is 3.14x41x41x77=369.5
piston sticks up 3.14x41.41.0.3=1.6
gasket is 3.14x41x41x1.3=6.86

Let X be the head volume.

So the BDC volume is
369.5+6.86+X-1.6-3.2 which is 371.56 + X

The TDC volume is
X +6.86 -1.6-3.2 which is X + 2.06

For an 11.3 to one CR
BDC volume = 11.3(TDC volume)
371.56 + X = 11.3(X + 2.06)
371.56 + X = 11.3X + 23.28
371.56-23.28 = 11.3X - X
348.28 = 10.3X
so X = 34.83


..and can I have 25minutes of my life back please!





from another forum wrote:oh, and account for the gasket too. so chamber volume will need to be

so swept volume is 406638.3mm^3

so your desired theoretical chamber volume will be 35985.7mm^3, just add or subtract the various volumes from this, no? is the "dome" of the piston convex or concave?



As to the chamber volume I'll need... I find to save time, and poor calculating skills on my part - I use one of the online compression calculators..... https://www.rbracing-rsr.com/compstaticcalc.html or http://www.csgnetwork.com/compcalc.html

either of these work.....


in both cases we come up with about 37cc (37.3 in the RB racing calculator)
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Thu May 07, 2015 12:27 pm

So with OST-031 now @ the machine shop getting its valve job and surfacing we delve back into OST-030


I've gotten the head back from the machine shop, they have provided a minimum resurfacing .003", to add to the previous clients report of a .008" resurfacing, the current surface is not quite @ .011, closer to .0102". This head is now 115.74mm thick, having had a total of .26mm removed.

Typically with a 10 thou cut you can expect chamber volumes to drop to about 35cc, the deshouding adds about .4cc, to gain volume I had the valve seats machined an extra .003" to gain 1cc in chamber volume, this lowers the valve on the seat allowing for a bit more volume in the chamber. The valve tips were cat an equal amount so use of more common shims sizes is retained.

Image

So right now the chambers sit @ 36.4cc (1/10cc tolerance)

Image

[QUOTE=oldeskewltoy;6155985]
All the cam journals look pretty much the same as this...
Image

Since MR2tailbreaker noticed a "small" problem in his cam and journal clearances using the Poncams, I'll be checking these journals for similar issues.....


[/QUOTE]

The FSM(BGB) states the cam to journal clearance to be .035mm to .072mm, with nothing greater then .1mm

Image


Using the Plastigage PL-X - The PL-X range is a bit on the tight side for measuring the whole range of the cam to journal - a bit too small for perfect accuracy, but in this case it works adequately.

Image

This is one of the measurements, you can see it is quite a bit narrower then .045mm which is middle tight of the span in the FSM.

By carefully surfacing the cam cap "feet" we can get this dimesion closer to the center of the specification

Image



Here is a 2nd journal going from a bit loose....

Image


to middle of the spec

Image


Of course the worst one I didn't get a photo of, that was #5 on the intake side... farthest from the oil supply, it was so loose that most of the Plastigage thread was intact when checked, and it too was brought into spec.


Now that the cam journals are all within tolerance, assembly can begin.....



More to come..... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

Elvin Wes
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Re: OST-030: a case in point

Postby Elvin Wes » Thu May 07, 2015 2:56 pm

You just wont stop wont you.

Energizer Bunny.
Keep up the good work.

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Thu May 07, 2015 6:42 pm

Elvin Wes wrote:You just wont stop wont you.

Energizer Bunny.
Keep up the good work.


no one else does it... and shows their work.... 8-)


Showing off her angles....

Image


oldeskewltoy wrote:
Now that the cam journals are all within tolerance, assembly can begin.....






The head and hardware are all laid out, #1 cylinder already has the valves in....

Image


Now half assembled...

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sometimes during assembly you see something that you just don't like.... tossed the retainer on the left for the one on the right. There was no other damage, I just didn't like that kind of a flaw.

Image



Fully assembled... now whats left is setting the valve clearances, and getting it back to my client.

Image





More to come...... :D
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Mon May 11, 2015 7:43 pm

Valves @ full lift...

Exhaust....

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Intake...

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oldeskewltoy wrote:Fully assembled... now whats left is setting the valve clearances, and getting it back to my client.


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Its packaged back in its case.... with the latch zip tied down...

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I heated the end of my punch a bit so I could get it to impress into the ziptie.

All that is left on this is shipping back to my client....
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

User avatar
oldeskewltoy
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Re: OST-030: a case in point

Postby oldeskewltoy » Sun May 24, 2015 8:44 am

oldeskewltoy wrote:
Image


All that is left on this is shipping back to my client....



Why I insist on insuring the finished product for its shipment back to it's owner......

Image



I've been told the head itself did not sustain any damage... but this shows significant intrusion.... so when I say the insurance adds $20, or $30 to the return shipping cost...

its just to COVER YOUR ASSets.
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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