no vacuum advance?
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
So 63Mako ( on my friends list and will remain there 
) If the instructions for this particular motor (not every small block ever made) clearly state
"Set spark timing at 32deg @ 3000rpm with with vacuum line from dist. removed and plugged. says this will produce 32 deg of total timing at WOT and the vacuum cannister should remain disconnected. This engine is designed to operate using only the interal centrifugal advance to acheive the correct timing curve"
This means that you ignore the instructions and run a vacuum canister ?
) If the instructions for this particular motor (not every small block ever made) clearly state "Set spark timing at 32deg @ 3000rpm with with vacuum line from dist. removed and plugged. says this will produce 32 deg of total timing at WOT and the vacuum cannister should remain disconnected. This engine is designed to operate using only the interal centrifugal advance to acheive the correct timing curve"
This means that you ignore the instructions and run a vacuum canister ?
The stock GM timing curves suck for performance, throttle response and in my opinion they were engineered to reduce power to limit warrantee claims on the engine, run hotter to aid in emmissions testing and reduce throttle response and low end power to keep the driveline together for 36,000 miles or 3 years even if you beat on it. These new crate engines are still mediocre powered SBC engines and will respond positively to the same tweeks that the originals would. The problem you have is they have a factory warrentee and use the same old tricks they have used for 50 years to limit their claims.
If there was ping resulting from tuning I would back off a little though.
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
I think some people just like to show how smart they are rather then help . When I read those instructions I see statements intended to be used to set timing,. Not operate motor in daily life.
Others can read them and suddenly become Mr GoodWrench .. More power to ya .. Ohh ya I happen to have a crate motor.. I get all in at 2800 and max advance to 50 plus while at idle and cruse speeds. Cant wait until my motor explodes lmao ..
Others can read them and suddenly become Mr GoodWrench .. More power to ya .. Ohh ya I happen to have a crate motor.. I get all in at 2800 and max advance to 50 plus while at idle and cruse speeds. Cant wait until my motor explodes lmao ..
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I think some people just like to show how smart they are rather then help . When I read those instructions I see statements intended to be used to set timing,. Not operate motor in daily life.
Others can read them and suddenly become Mr GoodWrench .. More power to ya .. Ohh ya I happen to have a crate motor.. I get all in at 2800 and max advance to 50 plus while at idle and cruse speeds. Cant wait until my motor explodes lmao ..
Others can read them and suddenly become Mr GoodWrench .. More power to ya .. Ohh ya I happen to have a crate motor.. I get all in at 2800 and max advance to 50 plus while at idle and cruse speeds. Cant wait until my motor explodes lmao ..
You guys do what you want I'm going to plug my toaster into a 220V outlet because I can't wait that long for my toast in the morning using 115V like in it says in the instructions.
Every engineer/product designer knows this acronym RTIS. When tech support used to get calls the telecom equipment I designed wasn't working properly the first thing they ask is did you read the instructions and most of the time the answer was no
My first post said everyone has there preference, vacuum advance or no vacuum advance and stated no one is going to change the others mind. What I am disputing is not doing what the instructions tell the buyer of this particular engine to do. At this point I don't care but warranty issues come into play if the engine isn't setup and run the way the builders intended, that's all I have to say besides the fact I don't like to be attacked for no reason by an someone I made no reference to in my posts that can't decipher instructions
Racer
Joined: May 2005
Posts: 399
Likes: 4
From: Suffield CT
Timing....it's everything.
I really like the discussion in here, and to OP:
I DON'T KNOW HOW TO FIX YOUR MOTOR
but hope i can help.
1. why can't you pretend to be buying the same motor again and call the company and ask? or ask them who to ask if they can't answer you directly ???
2. I am sure the folks already posting know about John Hinckley and his tech articles on how things work. you should give yourself some knowledge too.
http://camaros.org/articles.shtml
http://camaros.org/pdf/timing101.pdf
http://camaros.org/pdf/map_advance.pdf
3. You have HEI you said and not stock points setup, i do not know if that changes how you go about setting up your motor, you need to know.
4. If it's simple enough to hook up the vac adv and drive thru a tank of gas without destroying your motor, check and set your timing and do it.
If in your research you learn hooking it up can "blow" the motor up....don't, and work on plan B.
5. Work on filtering out the facts from the "this is what works for me" type posts, we have in this thread. Don't get me wrong, i think you will find some of the same info "word for word" in the links i gave as in some posts already given.
keep us posted on what fixes your issue....
Peace, Love, and Horsepower
-ALF out....
I DON'T KNOW HOW TO FIX YOUR MOTOR
but hope i can help.
1. why can't you pretend to be buying the same motor again and call the company and ask? or ask them who to ask if they can't answer you directly ???
2. I am sure the folks already posting know about John Hinckley and his tech articles on how things work. you should give yourself some knowledge too.
http://camaros.org/articles.shtml
http://camaros.org/pdf/timing101.pdf
http://camaros.org/pdf/map_advance.pdf
3. You have HEI you said and not stock points setup, i do not know if that changes how you go about setting up your motor, you need to know.
4. If it's simple enough to hook up the vac adv and drive thru a tank of gas without destroying your motor, check and set your timing and do it.
If in your research you learn hooking it up can "blow" the motor up....don't, and work on plan B.
5. Work on filtering out the facts from the "this is what works for me" type posts, we have in this thread. Don't get me wrong, i think you will find some of the same info "word for word" in the links i gave as in some posts already given.
keep us posted on what fixes your issue....
Peace, Love, and Horsepower
-ALF out....
Thread Starter
Racer
Joined: Apr 2007
Posts: 275
Likes: 1
From: Lafayette/marquez La/tx
My motor ain't broke...it actually runs really well..just poor gas mileage. A motorhead where I work said I need to hook up my vacuum advace and that would help. I was just wondering why Gm says not to. I kind of lean to less warranty issues. I am waiting on my dart 64cc/180cc 2.02/1.60 heads and my comp cam to come in. I have the motor ready to pull out and new heads should be here friday. I have an edelbrock 1407 on it right now which may be a little rich for the C.I. 74cc heads. I still may need to lean it out with the new heads.....time will tell. Also a performer EPS. Thinking about going to a RPM manifold. I did not mean for this topic to turn into such a heated discussion. Hope no one got their feelings hurt
Tech Contributor
Joined: Jun 2004
Posts: 20,910
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
"This engine is designed to operate using only the interal centrifugal advance to acheive the correct timing curve" Again, I disagree that any engine has the correct timing curve if it is running retarded at all non-WOT RPMs.You guys do what you want I'm going to plug my toaster into a 220V outlet because I can't wait that long for my toast in the morning using 115V like in it says in the instructions.
Every engineer/product designer knows this acronym RTIS. I spent decades as an IC/ECM/PCM design engineer. Never once saw the RTIS acronym until you just posted it. When tech support used to get calls the telecom equipment I designed wasn't working properly the first thing they ask is did you read the instructions and most of the time the answer was no
My first post said everyone has there preference, vacuum advance or no vacuum advance and stated no one is going to change the others mind. What I am disputing is not doing what the instructions tell the buyer of this particular engine to do. At this point I don't care but warranty issues come into play if the engine isn't setup and run the way the builders intended, that's all I have to say besides the fact I don't like to be attacked for no reason by an someone I made no reference to in my posts that can't decipher instructions
Every engineer/product designer knows this acronym RTIS. I spent decades as an IC/ECM/PCM design engineer. Never once saw the RTIS acronym until you just posted it. When tech support used to get calls the telecom equipment I designed wasn't working properly the first thing they ask is did you read the instructions and most of the time the answer was no
My first post said everyone has there preference, vacuum advance or no vacuum advance and stated no one is going to change the others mind. What I am disputing is not doing what the instructions tell the buyer of this particular engine to do. At this point I don't care but warranty issues come into play if the engine isn't setup and run the way the builders intended, that's all I have to say besides the fact I don't like to be attacked for no reason by an someone I made no reference to in my posts that can't decipher instructions
What engineering or physics disagreements do you have with what I just wrote?
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Again I haven't been referring to your posts until you attacked me for no reason. Just let the thread die I am not opening it again and you are on my ignore list so have at it I won't see it. BTW you are the greatest mechanic on the CF 
Last edited by MotorHead; Jan 1, 2013 at 06:39 PM.
Safety Car
Joined: Sep 2012
Posts: 4,688
Likes: 41
From: Palm Harbor, Florida
:
Every engineer/product designer knows this acronym RTIS. When tech support used to get calls the telecom equipment I designed wasn't working properly the first thing they ask is did you read the instructions and most of the time the answer was no
My first post said everyone has there preference, vacuum advance or no vacuum advance and stated no one is going to change the others mind. What I am disputing is not doing what the instructions tell the buyer of this particular engine to do. At this point I don't care but warranty issues come into play if the engine isn't setup and run the way the builders intended, that's all I have to say besides the fact I don't like to be attacked for no reason by an someone I made no reference to in my posts that can't decipher instructions
Every engineer/product designer knows this acronym RTIS. When tech support used to get calls the telecom equipment I designed wasn't working properly the first thing they ask is did you read the instructions and most of the time the answer was no
My first post said everyone has there preference, vacuum advance or no vacuum advance and stated no one is going to change the others mind. What I am disputing is not doing what the instructions tell the buyer of this particular engine to do. At this point I don't care but warranty issues come into play if the engine isn't setup and run the way the builders intended, that's all I have to say besides the fact I don't like to be attacked for no reason by an someone I made no reference to in my posts that can't decipher instructions
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Tech Contributor
Joined: Jun 2004
Posts: 20,910
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Ignore away.
BTW, I'm just an average mechanic. I'm a very good engineer, though.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
No one is going to change anyones opinion or say boy is he smart, you either like to run a vacuum advance or you don't. If a GM engineer gave me instructions not the run a vacuum advance on a brand new engine then I wouldn't run one, if your smarter than the guys who put the motor together and designed it / set it up to run with no vacuum can then run a vacuum advance. I don't run one and get good gas mileage with a 600HP engine.
It's pretty clear to me anyway "Set spark timing at 32deg @ 3000rpm with with vacuum line from dist. removed and plugged. says this will produce 32 deg of total timing at WOT and the vacuum canister should remain disconnected. This engine is designed to operate using only the internal centrifugal advance to achieve the correct timing curve"
Someone tell him to disregard this and run a vacuum advance and offer to pay for the motor if it detonates or anything else timing set wrong can ruin an engine.
So to the OP you get 10mpg, what is your A/F readings at idle, part throttle, cruise and WOT ? If you don't know that's why you get 10mpg
It's pretty clear to me anyway "Set spark timing at 32deg @ 3000rpm with with vacuum line from dist. removed and plugged. says this will produce 32 deg of total timing at WOT and the vacuum canister should remain disconnected. This engine is designed to operate using only the internal centrifugal advance to achieve the correct timing curve"
Someone tell him to disregard this and run a vacuum advance and offer to pay for the motor if it detonates or anything else timing set wrong can ruin an engine.
So to the OP you get 10mpg, what is your A/F readings at idle, part throttle, cruise and WOT ? If you don't know that's why you get 10mpg
Scott
