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Cylinder Bore Notching
https://slantsix.org/forum/viewtopic.php?t=6653		 Page 1 of 1
Author:  87Slant_sickness [ Thu Aug 21, 2003 7:31 pm ]
Post subject:  Cylinder Bore Notching
:x :x :x :x

hey all,

i tried the new cylenderhead on the car with the valves loose and all, the intakes clear the bore fine but the exhausts hit just alittle, so got any tips on notching the bores? need help before i get at it with a dremel :roll: 8)

How far down can the notches be? so far the porting is going well, there is alot of meat comming out of the head to match the gaskets, etc.... so any porting tips are welcome and also can any of you enlighten me as to where to be careful while porting?

daaaamn shes looking sooo sexy :) its smiling at me the whole time i'm working on it just like Doc's pic of his cylender head :lol: makes a tear come to my eye to see something finally comming together after 3weeks :cry: :)

Thanks all!
Justin

P.S. Doc, i remember awhile back you (or maybe someone else) having a pic of several cutaways (3 or 4 in the same pic i think) and i think the head was Yellow. do you still have this pic? i have the one thats got the marks on it and is black.... i cant find this other pic anywhere! THANKS
Author:  Doctor Dodge [ Thu Aug 21, 2003 9:24 pm ]
Post subject: 
Here is the link to that head picture:
http://www.dutra.org/pictures/engine/pa ... ction1.jpg

As for the exhaust valves not clearing, are they over 1.500 ?
How big is the cylinder bore?
I would stick the valves in a lathe and trim them down to fit into the bore size. this is much easer and less risky.
DD
Author:  87Slant_sickness [ Fri Aug 22, 2003 11:10 am ]
Post subject: 
Hey Doc,

Thanks for the pic!!!! as for the valves they are 1.56" exhaust :( i was certain they'd fit, reed had his valves in many different engines and they never hit, maybe the dang cylenderhead shop screwed up and angled them alittle too much?? :cry: maybe its just the engine i tried them on (i'm putting it on a stock bore slantsix) and i hope its just the 225 (79aspen 225R) engine that i tested it out on.

hmmm, cant wait to finish the head and CC the chambers :twisted: I do have to take alot out of the valve area where they cut the seats back (they just roughed them in for the moment incase i nicked one) then they'll finish it up later. i know they only hit by .015 i did the old paint on the block trick and then touched a valve to it.

i dont wanna touch the bottom end on this car right now, and if i cant make it work, i'll have a heavy 700dollar paperweight :cry:

Justin
Author:  Doc [ Fri Aug 22, 2003 1:12 pm ]
Post subject: 
1.535 exhaust valve head size is about as big as I can get without a lot of extra work, and that is based on at least a .060 overbore. (.100 is better)

If you are "bent" to make this work, (pun intended)
make a special cutter by brazing some chunks of cutting tool carbide onto the head of a junk valve the "dress" (grind) them to cut at the 1.56 size. (add a little extra for expansion clearance)

To use the cutter you will need to have a "stop ring" that bottoms -out on the valve guide top to limit the cutter depth.

Now the fun part, you drop the piston down to the bottom of the cylinder, put the special cutter in that cylinder's exhaust guide, set the cutter depth, install the head / cutter onto the engine, use a drill to drive the cutter and notch the edge of the cylinder, then pull the assembly off and do it all over agan for the next cylinder. Yup, 6 times to do the exhaust sides only.
I sure hope the engine is out of the car! :shock:
DD
Author:  87Slant_sickness [ Fri Aug 22, 2003 6:49 pm ]
Post subject: 
Doc, i am kinda hell bent to make it work :( i just dont understand why Reeds fit and mine wont... :cry:

i'm going to see if getting a sbf valve that is 1.5" and an 11/32 guide that is the same length as the stock slant valve will work, or if its too late for a smaller valve :(

I've so far taken ALOT of meat outta the head and taken some advice from a chevy guy to angle them guides! :shock: its gonna take me awhile to do it, but i have 4+ weeks before my B&M Manualpak transkit comes in... and no the engine isnt out of the car :cry: i havent actually even tested the head on that engine, i've been going by another engine that i have for a spare, so maybe its just that block thats not aligning...

Justin

P.S. So ugh Doc you wouldnt by any chance be willing to make me up a cutter and earn some extra $$$ now would ya? comman i know you wanna ;);););) and it dont have to be done for awhile!!
Author:  DusterIdiot [ Fri Aug 22, 2003 7:10 pm ]
Post subject:  The test block has....?
The test block has the engine to head aligning dowels still intact in the block right?

When I did my engine, they stuck in the head for some weird reason, and the machinist pulled them out and didn't return them when he finished.

Without those your head alignment cn be off...

-D.Idiot
Author:  87Slant_sickness [ Fri Aug 22, 2003 9:01 pm ]
Post subject: 
D.I, the test engine still has them, but i think it can move alittle bit, i guess i will not know for sure untill i have the head and everything ripped appart on my 80block... that will not be for awhile though...

Justin
Author:  Slant Cecil [ Sat Aug 23, 2003 6:25 am ]
Post subject: 
How do you angle the guides for an OS valve to clear and still get correct rocker tip contact?

Cecil
Author:  87Slant_sickness [ Sat Aug 23, 2003 4:48 pm ]
Post subject: 
no clue ;)

i'm new at this (my first head) and i went with the ford 300valves because Reed had such good success with his... maybe his shop turned them down alittle or??? i'm clueless, all i know is that i dont want this thing to be useless :shock:

Justin
Author:  Dart270 [ Mon Aug 25, 2003 7:11 am ]
Post subject: 
Either Reed's shop turned down the valves, used different ones w/o telling him, or that head has never been on an engine... :shock: I seem to remember that he hasn't used that head yet?

Lou
Author:  87Slant_sickness [ Mon Aug 25, 2003 11:48 am ]
Post subject: 
Hey Lou,

Hes had it on 3 different stock engines and ran them all for like 500 miles with that head on, of course those were with stock cams, etc. i'm guessing that this was a mistake that i wont make again lol, i'm curious to know if they are still the factory size of if they're turned down..either that or the stock cam and thick composition head gasket has saved them from hitting (?)

Justin
Author:  Doc [ Mon Aug 25, 2003 1:29 pm ]
Post subject: 
You need to try to turn down the heads of these valves.
Even if you trim .040 - .060 it will help you a bunch. (that is only a .020 - .030 cut)

Seeing that the seats are just "roughed-in" at this point, you may still have enough metal to support the reduced head diameter.

Your other options are much harder and carry more risk of failure.
DD
Author:  kesteb [ Mon Aug 25, 2003 4:41 pm ]
Post subject: 
I believe reed has had that head on a running engine. I also believe he dosen't really know what the valves are from or how they were installed. I believe Reed said that he told the machinest to but the biggest valves in and the machinest said they were from a 300 Ford. There should be a thread on the .com site with all of the information. Do a search.
Author:  MitchB [ Mon Aug 25, 2003 5:24 pm ]
Post subject: 
Notched bores for valve relief is nothing new. In your case, I don't believe the effort would be worth it though. You would probably gain more by running a notched bore with a smaller valve rather than having to notch the bore solely for clearance. When you get the valve that close to the wall, you knock a hell of a lot of flow off the edge that is shrouded. There's only one way to emperically determine this: that is to flow the head on the bench and then while bolted to the block. This would be a lot of work, but it could be done.

Mitch
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