Valve job on os valves

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RustyRatRod said:
I forget if you've said so forgive me, have you chosen a camshaft?
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for now im using my stock 72 bottom end (including the cam) as i did not pull the motor. Maybe this summer i will pull the motor and give the bottome end a refresh (rings bearings timing chain ect) When i do that i will take my cam up to orgen to get it reground for a turbo.
 
Slant Six Bumblebee said:
for now im using my stock 72 bottom end (including the cam) as i did not pull the motor. Maybe this summer i will pull the motor and give the bottome end a refresh (rings bearings timing chain ect) When i do that i will take my cam up to orgen to get it reground for a turbo.
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It oughtta have a lotta balls on the bottom end then!
 
Slant Six Bumblebee said:
Dont know how i missed that my apologies Only 16 and my eyes are playing tricks on me:eek:
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No Problem, there are times I wish I was 16 again,
Another way that OS valves can help is, if you have new seats cut into an existing valve seat, that can sink the valve further into the head and that really hurts flow at low lifts.
Cutting in new OS seats gets you a new valve seat up on top of the head where it belongs.
 
RustyRatRod said:
It oughtta have a lotta balls on the bottom end then!
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we will see i guess. My plan build the turbo motor then run it na while i build the rest of the car(I want to paint it reupholster new stearing suspension brakes and rewire the whole car MY WAY (relays 100% waterproof connectors all leds custom switches) the do the turbo right the first time.
 
my68barracuda said:
No Problem, there are times I wish I was 16 again,
Another way that OS valves can help is, if you have new seats cut into an existing valve seat, that can sink the valve further into the head and that really hurts flow at low lifts.
Cutting in new OS seats gets you a new valve seat up on top of the head where it belongs.
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this was one of the main reasons i went with the os valves because my current seats had some major pitting in them im surprised it ran as well as it did.
 
RustyRatRod said:
You're only 16 and you like slant sixes?

There might be hope for the world yet.
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Yeah it runs in the family just with bigger engines my mom has a 73 duster for her first car and my grandpa has a 73 challanger 383, 69 charger numbers matching 383.
I got my dart when i was 15 and have been fixing it up for a little over a year now.
 
Slant Six Bumblebee said:
Yeah it runs in the family just with bigger engines my mom has a 73 duster for her first car and my grandpa has a 73 challanger 383, 69 charger numbers matching 383.
I got my dart when i was 15 and have been fixing it up for a little over a year now.
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I'm impressed you don't want to throw it in the ditch for a V8.
 
RustyRatRod said:
I'm impressed you don't want to throw it in the ditch for a V8.
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well i did for a while espicly after getting my grandpa to floor it in his challanger as it has a stout motor (383 stroked with a 440 crank cam forged ect...) but i got real tired of the never ending line of v8s at every car show.
 
Slant Six Bumblebee said:
well i did for a while espicly after getting my grandpa to floor it in his challanger as it has a stout motor (383 stroked with a 440 crank cam forged ect...) but i got real tired of the never ending line of v8s at every car show.
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It's really boring, isn't it? I've had the most fun ever since I went to the slant 6.
 
0.066/ 0.069 (as 68 Barracuda had said) not much difference there. When I got the call to ask how much I wanted shaved off that head, I was driving and rounded it off to 0.007 per cc, to make for "easy, in my head" math.. That was how I came up with the figure of a 0.070 shave. they told me that my head had CC'd out at 60 cc before any shave. They still had it, just finished doing the seat work and such so I asked them to CC at least 1 chamber for me. after that shave I'm down to 48 cc on the smallest, (2 chambers) 49cc (2 more) and 50cc (the other 2) by my own CC measurements once I got it back/ so 70 thou got me about 10cc difference. I think they only CCd one chamber, before calling me.

the machinist had also said, that it measured out exactly what his machinist books listed a "447" casting /6 head, should measure out at. (before the shave)
 
Slant Six Bumblebee said:
I also figured if i get luck and my granpa doesnot sell his cars before i make more i can buy them from him and have a full aresonal
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be good to him, maybe he will "will" them to you especially if you show interest without being a pain.
 
Slant Six Bumblebee said:
Ok thanks all for the good info i have a better idea of what i need to do now. I have another question about how much to shave off the head. I am keeping the stock bottom end and using a .040 felpro and want to have a target compresion of 8.5:1 but dont know how much to take off. I know there are calculators but shaving the head will affect teh cc and i dont know how to calculate the new cc.
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0.060 off the block and 0.020 off the head gave me around 8.6-8.7 with a OEM steel head gasket.
 
Slant Six Bumblebee said:
Ok thanks all for the good info i have a better idea of what i need to do now. I have another question about how much to shave off the head. I am keeping the stock bottom end and using a .040 felpro and want to have a target compresion of 8.5:1 but dont know how much to take off. I know there are calculators but shaving the head will affect teh cc and i dont know how to calculate the new cc.
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are you sure you can get there with just cc volume? I have not studied your calculations here in depth but I recalled it would take a ton of shaving to get the cc’s to mid 8 CR when I was doing mine.
 
Slant Six Bumblebee said:
well i did for a while espicly after getting my grandpa to floor it in his challanger as it has a stout motor (383 stroked with a 440 crank cam forged ect...) but i got real tired of the never ending line of v8s at every car show.
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Case in point. A lot of beautiful V8 A Bodies at the MOPAR show a few weeks ago and the lowly /6 took top honors!

8FC257E3-DF14-459A-BFB9-C6FF6AC640B7.jpeg
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Jim Kueneman said:
are you sure you can get there with just cc volume? I have not studied your calculations here in depth but I recalled it would take a ton of shaving to get the cc’s to mid 8 CR when I was doing mine.
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Well using all my dimensions except the head cc and to get to 8.5:1 i would need to mill 46 thousands which does not seam excessive.

Screenshot 2022-03-15 at 11.00.29 AM.png
 
Jim Kueneman said:
are you sure you can get there with just cc volume? I have not studied your calculations here in depth but I recalled it would take a ton of shaving to get the cc’s to mid 8 CR when I was doing mine.
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I got to over 10:1 with milling the head on my current engine.....although it was not on purpose. LOL
 
Slant Six Bumblebee said:
well i am unsure of what my current cc is because im getting larger valves installed then i will cc my head and then cc the head after but i doubt it will be larger then 60
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I had oversized valves installed too and it did not make much difference.
 
RustyRatRod said:
I've seen @IQ52 (Jim Laroy) make the comment that larger valves make more power everywhere in the RPM range. He oughtta know. lol I think the larger valves are certainly worth it, especially with a slant 6.
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Dad said to me, "Jimmy, you gotta be smarter than your oversized valves when you install them too. Done wrong they can easily reduce your flow."

What did he know though?.......

Back in the '70's I saw his engines out pull Richard Petty's engines on the NASCAR straights.

Sigh....We could of used a more experienced driver back then.

Hold it..........What am I doing on the /6 forum?
 
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