[ap72]

No, I'm a civil, everyone swears I should have been a mechanical when they see me around cars, but I'm into bigger things, literally. mostly landfills right now, but it was water delivery in the past, and may be other piping in the future.

[carsavvycook]

Originally Posted by boatanchors

on a chevy small block - 383 what is the limit on compression when i have to stop using pump gas and go with the high dollar juice? i know some people might have different opinions im just looking for a rough number so i know my limit on this build.

After reading this whole thread, I felt this would be a good link to add. This confirms my lifelong experience's, in building, and tuning engines. Higher compression engines, require higher octane fuels, period.

You can try to run a small lift cam, in a higher compression engine, but you will need to run a real rich mixture of high octane fuel, and tune it perfectly. Larger lift cams, will allow you to cut down on the fuel mixture some, but you still need the higher octane fuels.

Here is a link, that answers your question, I hope.

http://www.faqs.org/faqs/autos/gasol...section-1.html

Stephen

PS: I like to tune them lean and mean, but have no detonation at wide open throttle.

Build yours up to a maximum of 10.3 CCR, so you can still run pump fuel.
It can be tuned to perform this way.

[ap72]

Originally Posted by carsavvycook

After reading this whole thread, I felt this would be a good link to add. This confirms my lifelong experience's, in building, and tuning engines. Higher compression engines, require higher octane fuels, period.

You can try to run a small lift cam, in a higher compression engine, but you will need to run a real rich mixture of high octane fuel, and tune it perfectly. Larger lift cams, will allow you to cut down on the fuel mixture some, but you still need the higher octane fuels.

Here is a link, that answers your question, I hope.

http://www.faqs.org/faqs/autos/gasol...section-1.html

Stephen

PS: I like to tune them lean and mean, but have no detonation at wide open throttle.

Build yours up to a maximum of 10.3 CCR, so you can still run pump fuel.
It can be tuned to perform this way.

Wow, that means most of todays engines coming off the assembly line can't work! I think we better call up the American big three and let them know they have it all wrong. Silly auto engineers are trying to defy the facts stated on that well made webpage.

[carsavvycook]

Originally Posted by ap72

Wow, that means most of todays engines coming off the assembly line can't work! I think we better call up the American big three and let them know they have it all wrong. Silly auto engineers are trying to defy the facts stated on that well made webpage.

Let me remind you, that this thread is about a SBC 383 Stroker (after market) not factory. Along with raising the compression above the 'factory' compression ratio's.

The OP's question is regarding compression........and pump fuel, and how high can you go.

You have 'twisted' some very good information, given by very knowledgeable members, on this thread. You make it sound like YOU wrote the Book on engine performance. I think NOT.

[ap72]

Originally Posted by carsavvycook

Let me remind you, that this thread is about a SBC 383 Stroker (after market) not factory. Along with raising the compression above the 'factory' compression ratio's.

The OP's question is regarding compression........and pump fuel, and how high can you go.

You have 'twisted' some very good information, given by very knowledgeable members, on this thread. You make it sound like YOU wrote the Book on engine performance. I think NOT.

I did no write the book, I could write a book, but books are only good once so I stay away from it. As far as 383 and aftermarket parts. We could talk about running some of the trick heads out there, equally trick valve train, with a rerouted cooling system and top of the line fuel and ignition control to allow for compression that can go past 12:1 on pump gas.

Or you can run 11:1 on well massaged Vortec's with a carb and HEI...

We're talking about what is possible, not what is common.

[glen242]

Originally Posted by ap72

No, I'm a civil, everyone swears I should have been a mechanical when they see me around cars, but I'm into bigger things, literally. mostly landfills right now, but it was water delivery in the past, and may be other piping in the future.

Civil Engineer?

This is from your profile:

Biography:
mechanic, attending SEMo for Construction Management, own a S10, a Blazer, a Cutlass, and a POS wish it would die Escort
Location:
St. Louis, MO
Interests:
cheerleading lifting
Occupation:
mechanic, part time laborer

23 years old - most good BS Engineering degrees require 5 years. Where did you get your BS and in what discipline? You claim Civil.

I am a retired Civil, registered land surveyor. BS University of Pittsburgh.

Do you really have a BS degree in any Engineering discipline?? How can you call yourself an engineer without a BS?

I asked you this question before, and received no answer.

[carsavvycook]

Originally Posted by ap72

I did no write the book, I could write a book, but books are only good once so I stay away from it. As far as 383 and aftermarket parts. We could talk about running some of the trick heads out there, equally trick valve train, with a rerouted cooling system and top of the line fuel and ignition control to allow for compression that can go past 12:1 on pump gas.

Or you can run 11:1 on well massaged Vortec's with a carb and HEI...

We're talking about what is possible, not what is common.

Exactly why I posted that link.

It is knowledge only verified with hands on experience. This takes years to acquire. This is not found on a computer program, or on the 'net'.

By the way, 12:1 will not run on pump gas.

I know from trial, and error. Trial + Error= Experience.

[ap72]

Originally Posted by glen242

Civil Engineer?

This is from your profile:

Biography:
mechanic, attending SEMo for Construction Management, own a S10, a Blazer, a Cutlass, and a POS wish it would die Escort
Location:
St. Louis, MO
Interests:
cheerleading lifting
Occupation:
mechanic, part time laborer

23 years old - most good BS Engineering degrees require 5 years. Where did you get your BS and in what discipline? You claim Civil.

I am a retired Civil, registered land surveyor. BS University of Pittsburgh.

Do you really have a BS degree in any Engineering discipline?? How can you call yourself an engineer without a BS?

I asked you this question before, and received no answer.

Yea, I have my BS, University of Missouri- Rolla, now called Missouri University of Science and Technology. Its really well known in the Midwest, but not really a big school, around 6,000 students, 80% of them engineering related. And yes, I got my MBA in Environmental and Industrial Management from SEMO (I taught Construction Management), and I will be starting my MS in Civil Engineering at SIUE this January. Hopefully eventually I'll make it back to Rolla for my doctorate, or maybe just settle at Wash U since its in town. I sit for my PE after Dec 2009.

That profile hasn't been updated in a LONG time. I guess I didn't think people actaully read it. And yes I'm 23, that part is current. I no longer cheerlead, may try to get on as an assistant coach though. And I'm curently a project engineer in the St. Louis area.

I'm also a Leo and I enjoy holding hands and long walks along the river.

[ap72]

Originally Posted by carsavvycook

Exactly why I posted that link.

It is knowledge only verified with hands on experience. This takes years to acquire. This is not found on a computer program, or on the 'net'.

By the way, 12:1 will not run on pump gas.

I know from trial, and error. Trial + Error= Experience.

I wish I could find the article, but I swore I saw a dyno challenge with ratios runnig a little over 13:1 on 93 octane. Of course these things were tuned perfectly, were dyno queens, and had exceptional cooling along with coatings.

To prove it can run in an engine look at motorcycles, a lot of them are running on pump gas at that ratio or higher- again its a different engine but it shows that it is possible to do with that octane.

I'm not saying I can build an engine to run 12:1, or rather would even try to (too cost prohibitive), but some people can get 10:1 to run on pump gas- doesn't mean someone else can't either.

For a long time man couldn't see beyond the stars in the night sky, then we sent up the Hubble, only to realize there's more that we can't see.

[carsavvycook]

Originally Posted by ap72

For a long time man couldn't see beyond the stars in the night sky, then we sent up the Hubble, only to realize there's more that we can't see.

Once again, you post a somewhat questionable remark aimed at a poster.

This reads to me(you quoted me) THAT I NEED TO LOOK OUTSIDE OF THE BOX(not yelling). Just trying to prove a point.

I have been blessed with mechanical abilities, by our all mighty God. I only have a high school diploma, and have been able to succeed in the automotive, and performance industry. The school of hard knocks is the best learning experience you can have.

Check my previous posts, and try to be less abrasive, and more open to the knowledge base available on this site.

If you want a summary of what I have accomplished, PM me.

Stephen

[ap72]

Originally Posted by carsavvycook

Once again, you post a somewhat questionable remark aimed at a poster.

This reads to me(you quoted me) THAT I NEED TO LOOK OUTSIDE OF THE BOX(not yelling). Just trying to prove a point.

I have been blessed with mechanical abilities, by our all mighty God. I only have a high school diploma, and have been able to succeed in the automotive, and performance industry. The school of hard knocks is the best learning experience you can have.

Check my previous posts, and try to be less abrasive, and more open to the knowledge base available on this site.

If you want a summary of what I have accomplished, PM me.

Stephen

Its not directed so much at you as it is all of us.

There was a time, back in the day of flat head fords, that if you said 9:1 you were out of your mind. Yet that's below factory now-a-days. And not to discredit expierence, because it is the reason we are where we are today, but expierence in itself is nothing if you do not analyze it properly and find the best way to apply it (I know a lot of well expierenced people who don't have much of anything to show for it).

I'm grateful for the learning of the men who walked this earth before me, but I'm also grateful for the people who challenged it.

[F-BIRD'88]

Originally Posted by ap72

Its not directed so much at you as it is all of us.

There was a time, back in the day of flat head fords, that if you said 9:1 you were out of your mind. Yet that's below factory now-a-days. And not to discredit expierence, because it is the reason we are where we are today, but expierence in itself is nothing if you do not analyze it properly and find the best way to apply it (I know a lot of well expierenced people who don't have much of anything to show for it).

I'm grateful for the learning of the men who walked this earth before me, but I'm also grateful for the people who challenged it.

Again because of your youth and inexperience you don;t know the history of the pre war era and flat heads. Before WWII the only gasoline available had a very low octane rating barely able to support a 6:1 compression ratio.
Not until after WWII did high octane leaded gas become available at the pump, allowing a higher compression ratio. 50 60 and early 70's mom and pop cars had higher compression ratio then we can run now. (cause you could buy the gas for them.
Many many racers modified their flat head motors to run on Methanol or ethanol with a very high compression ratio 12:1-13:1 +
Do some research using the terms Ricardo and high compression and detonation and catch up with the rest of humanity. All your fancy "modern" combustion chamber shapes and "out of the box" theories you see today were researched by Ricardo and others before WWII. A lot of thinking out of the box done back then to develop high performance fighter engines and "modern" high octane racing fuels.
Piston engines research took a back seat to the new "jet era" after WWII but the availabilty of cheap high octane gasoline allowed the "high compression" modern motor of today to be in every garage in the 50's and 60's.
Electric cars were perfected and readily avaliable before gasoline was readily avaiable.
Nothing much has changed on an internal combustion motor in 100 years.
But we'll let you go on it cause you are young and inexperienced.

[carsavvycook]

Originally Posted by ap72

Its not directed so much at you as it is all of us.

There was a time, back in the day of flat head fords, that if you said 9:1 you were out of your mind. Yet that's below factory now-a-days. And not to discredit expierence, because it is the reason we are where we are today, but expierence in itself is nothing if you do not analyze it properly and find the best way to apply it (I know a lot of well expierenced people who don't have much of anything to show for it).

I'm grateful for the learning of the men who walked this earth before me, but I'm also grateful for the people who challenged it.

I don't care who you know, or what they have to show for it. This is a 'no-namer' in our present economy. My $250K investment could go under any day now, but my knowledge cannot be taken away from me, except by my life's 'leader'.

Once again you post a twisted post. "but expierence in itself is nothing if you do not analyze it properly and find the best way to apply it"

What in the h**l do you think everyone in your lifetime is expected to do? Match your success? Everyone has a mind of their own, and winds up happy in their 'nitch' of their life. Not everyone is perfect.

This is what life is all about.

[carsavvycook]

Originally Posted by boatanchors

on a chevy small block - 383 what is the limit on compression when i have to stop using pump gas and go with the high dollar juice? i know some people might have different opinions im just looking for a rough number so i know my limit on this build.

boatanchors; Did you get the information you were looking for? Before this thread gets moved by the 'Mods'.

[ap72]

Originally Posted by carsavvycook

I don't care who you know, or what they have to show for it. This is a 'no-namer' in our present economy. My $250K investment could go under any day now, but my knowledge cannot be taken away from me, except by my life's 'leader'.

Once again you post a twisted post. "but expierence in itself is nothing if you do not analyze it properly and find the best way to apply it"

What in the h**l do you think everyone in your lifetime is expected to do? Match your success? Everyone has a mind of their own, and winds up happy in their 'nitch' of their life. Not everyone is perfect.

This is what life is all about.

I'm sorry I ticked you off, but I really have made no personal attack in my posts. And I never claimed to be perfect, nor do I expect anyone else to be.

I'm only saying that expierence is in itself meaningless, If I put my hand in a fire and get burned I have expierenced burning and pain. If I do not analyze what has happened and deduce that fire will hurt me if not treated properly then I have learned nothing. Likewise if I assume that all fire is bad and painful then I have "learned" something, but I will never realize the bennifits of its heat and light because I have learned to not go near it at all. No one can argue that point. Many people who have done things before us have shown us some of the possibilities, but no one has yet discovered all of the limitations, and even when these "limits" are set it is only a matter of time before someone else finds a way to push through them. Just like when Columbus rediscovered America.

I am not trying to say that I am going to rediscover America either. Merely that none of these so called constants should not be taken for granted, all of them have changed in the past and will change in the future.

And to F'bird, I know the gas back in the day was crap, refining has made some improvements since then. Likewise even when there was leaded gasoline I would not run those engines run on today's gas unless I wanted the valves to chew up the heads. I would also not run todays engines on that leaded gas because the fuel and exhaust system can't take it.

Not only has the technology in engine design and manufacturing changed, but so have the parameters. Nothing is constant, nothing is set in stone.

Lastly cook, I'm not trying to discount what you say or what you know, but knowledge does expire. What you know is worth the most when you learn it, and as time goes by and the world changes so does the value of your knowledge.

There was a time when simple potassium nitrate was the best chemical to have in warfare, and then came trinitrotoluene, then the A-bomb, then the H-bomb, and now... well only God knows all of what they have. Each invention served its purpose in shaping the world, each inventor was just as crucial, and each one's importance began diminishing as soon as their product came into use.