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Discussion Starter #2
A Really Nice Static Compression Ratio calculator by Diamond Pistons I used.
It also calculates the Compression Height or Pin setting required.
You need to verify measure the true deck height of your chosen block & allow for a cleanup cut on both banks.
Tolerances were allover by GM typical.


For the guys building their own Race Engines like I am doing.
Allows you to get every bit of HP & torque possible from your engine combination.
Also important with Nitrous power adders & Boost.
What You think you have is often 1-2 numerical numbers lower.
Have to check & measure all. CC your cylinder head combustion chambers like I have.


A bump in compression from 9.0:1 or 10.0:1 to 12.5- 13.0:1 is worth 80-120 Hp more typical nothing else done.


Theory & Race math more than can be covered here.
 

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Don't forget to order your pistons after you've chosen a cam. Are you planning to run on pump gas (93 octane)? While static compression is great for bragging rights rarely does a cam close the intake valves at BDC, It's usually 40-70 degrees after BDC. That will lower your compression because there's not as much volume to squeeze. I have ran engines at 8.5-9.5 dynamic compression with a good set of heads/pistons and a lot of detail put into to the shape of the piston crown and combustion chambers. A good quench will allow a bit more compression as will a coating on the piston. I don't use coatings but I'm not after every last horsepower. Reliability, power and longevity are the key for me.

I once screwed up and ran a .036 quench trying for every last bit of compression I could. After a 5000 mile teardown to replace the heads with a better set I found the valve outline on the carbon on top of the piston. There was no noise and the valves never touched the pistons. I'm guessing that my pidton to valve clearance was probably around .0001. I was lucky. Now I shoot for .040 quench and the pistons have a nice flat area to get that quench working.

I'm certain that you know all this stuff but I just wanted to give some personal experience. Good luck with the build.:thumbsup:
 

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Discussion Starter #4
Don't forget to order your pistons after you've chosen a cam. Are you planning to run on pump gas (93 octane)? While static compression is great for bragging rights rarely does a cam close the intake valves at BDC, It's usually 40-70 degrees after BDC. That will lower your compression because there's not as much volume to squeeze. I have ran engines at 8.5-9.5 dynamic compression with a good set of heads/pistons and a lot of detail put into to the shape of the piston crown and combustion chambers. A good quench will allow a bit more compression as will a coating on the piston. I don't use coatings but I'm not after every last horsepower. Reliability, power and longevity are the key for me.

I once screwed up and ran a .036 quench trying for every last bit of compression I could. After a 5000 mile teardown to replace the heads with a better set I found the valve outline on the carbon on top of the piston. There was no noise and the valves never touched the pistons. I'm guessing that my pidton to valve clearance was probably around .0001. I was lucky. Now I shoot for .040 quench and the pistons have a nice flat area to get that quench working.

I'm certain that you know all this stuff but I just wanted to give some personal experience. Good luck with the build.:thumbsup:
No Race Gas Gunny.
110 Motor Octane Uncut .

I have had good results with 100 AV gas in past too.
 

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Discussion Starter #5
Don't forget to order your pistons after you've chosen a cam. Are you planning to run on pump gas (93 octane)? While static compression is great for bragging rights rarely does a cam close the intake valves at BDC, It's usually 40-70 degrees after BDC. That will lower your compression because there's not as much volume to squeeze. I have ran engines at 8.5-9.5 dynamic compression with a good set of heads/pistons and a lot of detail put into to the shape of the piston crown and combustion chambers. A good quench will allow a bit more compression as will a coating on the piston. I don't use coatings but I'm not after every last horsepower. Reliability, power and longevity are the key for me.

I once screwed up and ran a .036 quench trying for every last bit of compression I could. After a 5000 mile teardown to replace the heads with a better set I found the valve outline on the carbon on top of the piston. There was no noise and the valves never touched the pistons. I'm guessing that my pidton to valve clearance was probably around .0001. I was lucky. Now I shoot for .040 quench and the pistons have a nice flat area to get that quench working.

I'm certain that you know all this stuff but I just wanted to give some personal experience. Good luck with the build.:thumbsup:
290-310 psi cranking compression .
What my Bought Isky Full Race Cam will provide.
For all.out Race.
Can cruise as long as pure High Octane in the tank.

Got the Vette for long distance pump gas cruise duties.

Get about 20 mph in past no Overdrive Muncie 4.
Not bad for a Dinosaur tech.
 

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I have had good results with 100 AV gas in past too
I've ran 115/145 AVgas in my cars while in the Marines. Fill up at your friendly local neighborhood air station. At a red light my eyes watered like I'd been in a tear gas chamber. That may have been a bit much but it was real cheap. Your Mom and Dad bought it for me. :laughing:

I live in Ashland, KY where there is a refinery. They make Valvoline oil and even made the secret fuel for the SR-71. I asked a friend of mine who works at the Product Application Laboratory about AV gas and we ran some samples. The aromatics are really high and the lead is unacceptable because of the potential for a lead buildup in engines. It great for high compression, big cubic inch, low RPM airplane engines but sucked as an alternative fuel for vehicles. I would be afraid to use it knowing what the test results were. But.......to each his own. We learn mostly from our mistakes and I've been there, done that and have the refrigerator magnet and the t-shirt to prove it.:D When your experience is greater than my lab results I have a spare refrigerator magnet. The t-shirt is on you.:devil:
 

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Discussion Starter #7
I've ran 115/145 AVgas in my cars while in the Marines. Fill up at your friendly local neighborhood air station. At a red light my eyes watered like I'd been in a tear gas chamber. That may have been a bit much but it was real cheap. Your Mom and Dad bought it for me. :laughing:

I live in Ashland, KY where there is a refinery. They make Valvoline oil and even made the secret fuel for the SR-71. I asked a friend of mine who works at the Product Application Laboratory about AV gas and we ran some samples. The aromatics are really high and the lead is unacceptable because of the potential for a lead buildup in engines. It great for high compression, big cubic inch, low RPM airplane engines but sucked as an alternative fuel for vehicles. I would be afraid to use it knowing what the test results were. But.......to each his own. We learn mostly from our mistakes and I've been there, done that and have the refrigerator magnet and the t-shirt to prove it.:D When your experience is greater than my lab results I have a spare refrigerator magnet. The t-shirt is on you.:devil:
I have experience with Pontiac V8 and racing them Gunny.
More Titanium used this time around.
Knocking about 3 pounds rotating reciprocating mass out.

Emergency Power also.
Race a Demon on Race Gas and beat him.
 

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290-310 psi cranking compression .
What my Bought Isky Full Race Cam will provide.
Are you building a 455 SD diesel? That's a lot of cranking compression. Heck, you might not even need sparking plugs. What are the cam specs?
 

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Discussion Starter #9
Are you building a 455 SD diesel? That's a lot of cranking compression. Heck, you might not even need sparking plugs. What are the cam specs?
Full Race.
Hotter than you got Gunny.
Big cubes cubic inches tamed down mainly crank stroke.

15:1 static possible if I angle mill the heads and Flat tops.
Cool thing about Pontiacs.

Not going to do that.

Several months away from running.
Have to wait.
I will make a Video of me Street Racing Flat Out for You.
Gunny style Balls out .
But Poncho.
Bob & Me going to Street Race again.
You will like his 1970 Charger SE.
Beautiful too.
 

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Discussion Starter #10
Are you building a 455 SD diesel? That's a lot of cranking compression. Heck, you might not even need sparking plugs. What are the cam specs?
1st one I built in 1996 had that much cranking compression.
 

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1st one I built in 1996 had that much cranking compression.
Cat, Cummins or Detroit? What are the cam specs? You might want to re-calculate.

Full Race.
Hotter than you got Gunny.
Yep, hotter than me for sure. But......I can drive to Chicago playing my stereo, air conditioning running on a hot Summer day and then drive on to Bakersfield Raceway in California and drive home. Different builds. Do you care to try to follow me? I'd bet that wouldn't work out for you.

Small blocks can make enough power in a great big ole' Impala to make the Poncho look bad. 1000 HP is no big problem.

 

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Discussion Starter #12
Cat, Cummins or Detroit? What are the cam specs? You might want to re-calculate.



Yep, hotter than me for sure. But......I can drive to Chicago playing my stereo, air conditioning running on a hot Summer day and then drive on to Bakersfield Raceway in California and drive home. Different builds. Do you care to try to follow me? I'd bet that wouldn't work out for you.

Small blocks can make enough power in a great big ole' Impala to make the Poncho look bad. 1000 HP is no big problem.

Do It.
Twin Turbo It Gunny.
Give it 65 PSI High Boost.


Grumpy Rated all Factory Small Block Chevies Blocks good to 360 HP.
That's It.
Anymore is on Borrowed Time.


Dart SHP is only good for 650 HP.


Dart Little M Block is rated for 1000 HP.
Cost is Over $3,000 Summit Racing.


Unfortunate Limited.


Going to have over 1000 HP.
3200 lbs with me seated.
Lighter than a C4 Corvette.
Pontiac Power.
 

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Discussion Starter #13
Even Scavenging Gunny all still cost $20,000 cash to start.


Real World $40K.


Pay a Pro $100-200K.
 

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Grumpy Rated all Factory Small Block Chevies Blocks good to 360 HP.
That's It.
Anymore is on Borrowed Time.
I hope the Grim Reaper is using that "borrowed time" watch. I may be immortal. You do realize that there are millions of hot rodders with SBC engines and block failures are very, very rare. You know, splayed caps, ARP and such. I'm pretty sure you didn't read that right.

What my Bought Isky Full Race Cam will provide.
Take a pic of the cam. What are the specs?
 

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Discussion Starter #17
I hope the Grim Reaper is using that "borrowed time" watch. I may be immortal. You do realize that there are millions of hot rodders with SBC engines and block failures are very, very rare. You know, splayed caps, ARP and such. I'm pretty sure you didn't read that right.



Take a pic of the cam. What are the specs?
The Cam will not work right Gunny for a Chevy.
It's made for a Pontiac V8.
Gotta keep something to myself.
Going to for now.

Be an EFI Tuning nightmare.
Makes little vacuum at idle. 2-4 inches only.

I don't know.....Grumpy sets. Posts his millions of links.
Big dilemma guys want huge Hp.
Costs alot all new.
Nothing Chevy left.
Why I went back to my TA. Just affordable for me.
Kool car too.

Hardblock it Gunny.
Use an electric water pump.
 

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No Cam specs, Diamond custom pistons, Titanium rods and no pics. Right.:rolling: I know, you're keeping it a secret so the street outlaws wan't know what you have when you bust their butt.
 

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Discussion Starter #19
No Cam specs, Diamond custom pistons, Titanium rods and no pics. Right.:rolling: I know, you're keeping it a secret so the street outlaws wan't know what you have when you bust their butt.
On a track I would get my Ass Handed to me by the Street Outlaws. Daddy Dave is rumored to have 5000 Hp now.
Big Chevy Twin Turbo.
Look like Twin 90's.
Big Chief falls short present. At 4000 Hp.
Crank up the boost.

I have Full Manley Titanium valves.
Much boxed up. Been waiting. Never photoed all.
You have to wait.
Late night play is my fun.
Like Full mile or 2 also.
Run ultra high speeds.
Speedo does not stop at 160 in TA. Keeps going past.No stop pin.
 

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Well, all-righty then.
 
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