Timing Dance ! Vacume Advance ?

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pilotsf

pilotsf

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So back again for your HONEST answers ! I have a medium build 10,000 mile 360 in my dart. I have had lag and hesitation always for the past year. I have tried everything. I ran 13.50 at 102mph so its not to bad. But that small hesitation drives me nuts. HELP !
When I try to set my timing with a dial back light I rev to around 3,000rpm set it to 34 and it dances to advance around 34 /36. At idle it dances around 17/18. When I change the dial back light from 34 to 36 the mark dosen't really change. Also what do you guys think about capping the vacuum advance on the distributor and carb. That's How my builder said to go and drive it that way, but many people say it will ruin my motor. I have the mopar orange box and vacuum distributor. If this is all good I'm going to rip off the carb and throw it in the sf bay. (edelbrock 800 cfm) .
Thanks for all the previous help too !!!
Dale
 
I would double check your timing with another timing light, and or check your timing light on another vehicle to verify that the light is functioning properly. Other reasons for the timing to "dance" timing chain slack (does your motor have a tensioner installed?) worn distributor. Not sure how capping the vacuum advance could ruin your motor, would just prevent additional advance at cruise rpm.
 
Almost forgot, you should be doing your timing checks withe vacuum advance disconnected/ capped. Does your timing continue to advance above 3000 rpm? if so you should consider lighter centrifugal advance springs to bring your total advance in sooner.
 
Take off the vacume advance line and plug the vacume port on the motor it was used for and make it a pure mechanical distributor.
Thats how i run all my cars and it works great.

Vacume canisters just mess with your timing and it sounds to me like your looking for a performance tuned engine.
Your engine builder told you to do it for a reason.#-o

Just install a set of light weight performance springs in your distributor.
Mancini racing sells them for $12.
There has been so much talk on here about this the last couple weeks and everyone is a little confused on what all this means.

It's the first thing you do to any distributor to make a world of differance.
It's one of the first things mopar performance told me to do back in the mid 90's and it's nothing new.
Do this first and don't look back.
Your timing will dance around with the heavy springs because it takes so much rpm to open open them up all the way.
They just start to open and your looking at the stock springs mess with the timing.
Loose the vacume advance and the stock distributor springs.
BUILD A SOLID AND MORE STABLE DISTRIBUTOR ,FOR MORE STABLE TIMING AND MORE HORSE POWER.

If a motor has a hesitation when put to the floor,most of the time it's not getting a big enough shot of gas from your carbs excellerator pump.


Put a 750 holley mechanical secondary 4150 on it.
Very easy to work on and is perfect for your engine.
I run a 4150 ON my 360 and even on my 318.
Yes ,a 318 with a 750 carb.
Too much carb-----no way \\ GOOD LUCK8)

p.s>Don't be scared ||| just try it.
 
Vacuum advance is necessary for ANY engine on the street for cleaner running and better cruising gas mileage. Yes you can just plug it and the car will run fine but your timing will be retarded from optimal when cruising with part throttle (unburned fuel collects in cylinders and goes out the tailpipe because it burns too slowly). Make sure the vacuum line is hooked up to ported vacuum, NOT manifold and when setting the initial/total+mech advance be sure to disconnect the hose.
 
Mopekidd-3,
If you install a lighter set of springs ,it will give you more timing down low were your vacume canister is bumping up the timing now.
A stock distributors ---heavy springs ---won't let the mechanical weights advance all the way untill 3500 rpm's or more.
The light weight springs WILL LET THE WEIGHTS ADVANCE FASTER
(2200 RPMS)
If your running the stock springs then the canister will help,BUT why not install the light weight springs and see the differance in power.

This makes the distributor just like a mopar performance distributor that cost $132 bucks.
The springs are only $12 bucks.
Mopar installs the springs and charges you $132 bucks for a modified stock distributor.
Why do you think they sell this with all there crate motors.

Everyone is missing out if they don't have a performance distributor on there motor.
I am really surprized at all the people that don't have a advanced curve distributor.
 
FWIW, the Mopar Performance distributor has a fully adjustable mechanical advance so you get more for your bucks than just a stock distributor with light springs. Also, the MP distributor does not have the phasing issues that the stock distributor has and the action of the vacuum advance is smoother and more consistent. Don't be fooled by the stock looking housing, internally it's the same as a Mallory performance distributor. If you are running a bigger cam and/or more compression than stock it is very likely that you will need to run a lot more initial timing than stock which will require you to limit the advance so you don't have too much on the top end, this distributor makes that a snap with the adjustable stops and also has a much wider selection of springs available to dial in the rate.

At light throttle low load cruising you need a lot more timing than the mechanical advance can give you. Yes you will get more timing at a lower rpm with light springs but for maximum efficiency and economy when cruising you need 40 or more degrees of timing.

My son had given me a MP billet distributor for fathers day which I put into my 360 when I built it. I never felt right about not having a vacuum advance so after a couple of years I switched back to the MP vacuum advance distributor. I gave up zero in power or driveability and picked up 1.5-2 mpg on my daily commute not to mention the cleaner running engine and less carbon build up.

I can't imagine why anyone that is using there car regularly on the street wouldn't want a vacuum advance.
 
dgc333,
Yes it can be a benifit and make a motor run cleaner.
You sould run the vacume advance if you have a stock distributor.

If you run the vacume advance on a modified distributor, you have to be really careful with what you dial the distributor in for and how much timing you give it.
If you don't have a big enough cam in your car and have a motor that has very high cylinder presure your taking a chance with detination.
For example:
Your driving your car down a road, and you have to climb a hill under part throttle.
You gave your car 35 degrees total mechanical advance and you have 15 degrees extra the vacume canister is giving you.
At this point you are at 50 total degrees timing and are having detination problems.
So you dial the vacume advance back to 5 additional deegres.
Now you have 40 going up the same hill due to the load on the engine.
A engine that has high cylinder presure will still most likely have detination problems.(smaller cams \\ no gear \\low stall convertor)
When you run a bigger cam ,AND HAVE LOWER CYILINDER PRESURE you can run the vacume canister BUT BE CAREFULL.

I don't take the chance of being in the wrong situation and having the motor pay the price.
FOR EXAMPLE: HOT DAY\\BIG HILL \\ THREE QUARTERS THROTTLE.
REMEMBER (((( YOU CAN'T ALWAYS HERE DETINATION))))

If it's all about drag racing then it gives you no benifit, and you will not have any detination problems creep up on you.

It can help your fuel millage for sure but you better now what your doing and what your motor is doing under all kinds of driving.
Detination will kill a motor faster then carbon.
I don't have to worry about carbon because i run alot of gear in my cars and they don't carbon up that easy.(higher rpm's)

If it works \\ keep doing what your doing \\ It's all good.
The factory put vacume advance on the distributors for a reason.
It's all about drag racing for me and some times being in the middle isn't so bad,JUST BE CAREFULL.
 
Pilots,
As was noted, initial and total timing should be checked with the vacuum can unplugged and the line to the carb capped. Thsi is to eliminate any variation the vacuum advance might be adding. If you do this and it still moves, it could be seomthing mechanical but I wouldn't worry about it. Simply keep an eye on it. If it gets worse you can look into it. There is an adjustment on teh vacuum can on the dsitributor. Take an 11/32 allen wrench and go straight into the nipple where the vacuum line plugs on. The wrench will go in and seat in a screw inside there. By turning that screw counterclockwise, you add preload to the advance and slow it's response. This does not limit or change the amount of degrees it adds, just raises the level of vacuum required to move it. If I had to guess I'd say your stumble is the advancetrying to come in too early when the vacuum signal is changing with the throttle at part throttle driving.

T67 - I'm pretty sure there are a lot of guys that know how a vacuum advance works, and want it. Perhaps if you want to convince someone to try it, explain why without yelling (CAPS). Saying don't think just do is just stupid... we're here to learn. Not take commands.
 
Perhaps he meant to use italics? I know it took me untill re ently to learn how to make my words appear on the screen lke that. And I used to use capitals too.
 
I have ran into a few things that cause timing to dance around. For one was the bronze oil pump/dist. drive bushing in the block replaced when it was rebuilt? If not it can let the dist. drive flop around and cause the timing to dance. I learned that one the hard way because the first small block I rebuilt yrs. ago I didn't change it on and had that problem. I pulled it back apart and changed it and problem gone. I also ran into a sloppy distributor once (worn bushings) that the timing danced around on. Replaced the bushings and problem fixed. I also ran into one that had a problem in the ECU but it never was a problem until above 4000 so that's probably not your problem although you just never know. As far as the hesitation it could be a lean condition in the carb. How do the plugs look? Is the hesitation worse when the engine is cold? If so it's probably lean and a re-jetting might fix it. Eddy carbs are just fine when jetted properly. Out of the box most carbs need a little touch up because there are so many variables in engine builds.

Also note that in the last week or so the use of vacuum advance has been brought up and a discussion about it. Here are my feelings. If it's a street car keep the vacuum advance and tune it like Moper said except I think he made a typo as it's a 11/64 allen wrench used to adjust the vacuum advance canister. If it's a race car you don't need vacuum advance. On a street car it will help fuel mileage and help keep carbon build up down and improve MPG. I recently swapped from a full mechanical dist. to a blueprinted stock type dist. utilizing vacuum advance and my car responded nicely. When it's cold it runs better cause on fast idle it's pulling the vacuum advance giving it more timing when it needs it cold. The cruising mpg went up about 2 mpg. Not a tremendous gain but one that will surely add up. I also noticed the plugs are running a little cleaner. Oh yeah another thing is if you do play with the distributor watch about installing both light weight springs that come in the spring kit as they will make it be at full advance by 1000-1200 rpm which may be too fast for your car and cause spark knock which will destroy the engine fast. Using both light springs can also cause problems getting the carb idle to be stable cause the timing flutters. Just use one light spring and the stock spring that isn't elongated. That'll give you total advance by about 2000-2400 rpm which is about right for a hot street setup.
 
Fish68,
Very well written.:thumblef:
Im glad that you understand the way distributors work and have yours set up for your motor.
The two things i liked most were the fact that you said, not to use the vacume advance on a drag car, and if you do use it on a sreet car to have it blueprinted.
My main concern was people with performance steet motors cranking there timing up and possibly hurting there motors.
The only way to effectivly adjust your distributor and use the vacume advance, is to run it on a distributor machine and adjust the canister to give the right amount of advance for every thousand rpm's.
That is what a blueprinted distributor is.
I ran my distributor i run now in my 318 on my freinds distributor machine and adjusted it to my combination.
It's strickly a mechanical distributer for street racing and bracket racing.
Having acess to a distributor machine is a blessing.

Mopar performance has a book on small block A engines for anybody who dosen't already know ,and it covers every little performance secret that mopar ever found out.:read2:
 
Take the dist apart and clean it. Set the initial timing per a vacuum gauge, Then read what the engine wants for initial. then change the mechanical in the dist, to be all in at 2000 or less, and limited to the initial plus whatever to 36 degees+ or-.
Then hook your vacuum advance to ported. You want that 50 degrees that the vacuum gives you at cruise , steady throttle. When you push on the gas pedal, the vacuum advance starts dropping out, as the vacuum in the manifold, and carb(that's why ported) starts dropping. At WOT, no vacuum=no vacuum advance, zero vacuum ; it drops out.
 
T67POWER said:
Take off the vacume advance line and plug the vacume port on the motor it was used for and make it a pure mechanical distributor.
Thats how i run all my cars and it works great.

Vacume canisters just mess with your timing and it sounds to me like your looking for a performance tuned engine.
Your engine builder told you to do it for a reason.#-o

Just install a set of light weight performance springs in your distributor.
Mancini racing sells them for $12.
There has been so much talk on here about this the last couple weeks and everyone is a little confused on what all this means.

It's the first thing you do to any distributor to make a world of differance.
It's one of the first things mopar performance told me to do back in the mid 90's and it's nothing new.
Do this first and don't look back.
Your timing will dance around with the heavy springs because it takes so much rpm to open open them up all the way.
They just start to open and your looking at the stock springs mess with the timing.
Loose the vacume advance and the stock distributor springs.
BUILD A SOLID AND MORE STABLE DISTRIBUTOR ,FOR MORE STABLE TIMING AND MORE HORSE POWER.

If a motor has a hesitation when put to the floor,most of the time it's not getting a big enough shot of gas from your carbs excellerator pump.


Put a 750 holley mechanical secondary 4150 on it.
Very easy to work on and is perfect for your engine.
I run a 4150 ON my 360 and even on my 318.
Yes ,a 318 with a 750 carb.
Too much carb-----no way \\ GOOD LUCK8)

p.s>Don't be scared ||| just try it.
Click to expand...

Thanks !!! Is it easy to put the springs in ? I will figure it out. Everyone tells me to chuck the 800 edelbrock . I think it has a lean spot and maybe its to big. I have taken it apart and set the floats and checked the acc pump. I'm just burnt ! i want to race in napa next month. Thanks for your input.
 
T67POWER said:
Take off the vacume advance line and plug the vacume port on the motor it was used for and make it a pure mechanical distributor.
Thats how i run all my cars and it works great.

Vacume canisters just mess with your timing and it sounds to me like your looking for a performance tuned engine.
Your engine builder told you to do it for a reason.#-o

Just install a set of light weight performance springs in your distributor.
Mancini racing sells them for $12.
There has been so much talk on here about this the last couple weeks and everyone is a little confused on what all this means.

It's the first thing you do to any distributor to make a world of differance.
It's one of the first things mopar performance told me to do back in the mid 90's and it's nothing new.
Do this first and don't look back.
Your timing will dance around with the heavy springs because it takes so much rpm to open open them up all the way.
They just start to open and your looking at the stock springs mess with the timing.
Loose the vacume advance and the stock distributor springs.
BUILD A SOLID AND MORE STABLE DISTRIBUTOR ,FOR MORE STABLE TIMING AND MORE HORSE POWER.

If a motor has a hesitation when put to the floor,most of the time it's not getting a big enough shot of gas from your carbs excellerator pump.


Put a 750 holley mechanical secondary 4150 on it.
Very easy to work on and is perfect for your engine.
I run a 4150 ON my 360 and even on my 318.
Yes ,a 318 with a 750 carb.
Too much carb-----no way \\ GOOD LUCK8)

p.s>Don't be scared ||| just try it.
Click to expand...

Nick M. said:
I would double check your timing with another timing light, and or check your timing light on another vehicle to verify that the light is functioning properly. Other reasons for the timing to "dance" timing chain slack (does your motor have a tensioner installed?) worn distributor. Not sure how capping the vacuum advance could ruin your motor, would just prevent additional advance at cruise rpm.
Click to expand...

very small slack ( i checked it when i changed fuel pump) and all parts on motor are new . (under 10,000miles) Thanks
 
T67POWER said:
Mopekidd-3,
If you install a lighter set of springs ,it will give you more timing down low were your vacume canister is bumping up the timing now.
A stock distributors ---heavy springs ---won't let the mechanical weights advance all the way untill 3500 rpm's or more.
The light weight springs WILL LET THE WEIGHTS ADVANCE FASTER
(2200 RPMS)
If your running the stock springs then the canister will help,BUT why not install the light weight springs and see the differance in power.

This makes the distributor just like a mopar performance distributor that cost $132 bucks.
The springs are only $12 bucks.
Mopar installs the springs and charges you $132 bucks for a modified stock distributor.
Why do you think they sell this with all there crate motors.

Everyone is missing out if they don't have a performance distributor on there motor.
I am really surprized at all the people that don't have a advanced curve distributor.
Click to expand...

I have the mopar performance distributor now. Still add springs ?
 
fishy68 said:
I have ran into a few things that cause timing to dance around. For one was the bronze oil pump/dist. drive bushing in the block replaced when it was rebuilt? If not it can let the dist. drive flop around and cause the timing to dance. I learned that one the hard way because the first small block I rebuilt yrs. ago I didn't change it on and had that problem. I pulled it back apart and changed it and problem gone. I also ran into a sloppy distributor once (worn bushings) that the timing danced around on. Replaced the bushings and problem fixed. I also ran into one that had a problem in the ECU but it never was a problem until above 4000 so that's probably not your problem although you just never know. As far as the hesitation it could be a lean condition in the carb. How do the plugs look? Is the hesitation worse when the engine is cold? If so it's probably lean and a re-jetting might fix it. Eddy carbs are just fine when jetted properly. Out of the box most carbs need a little touch up because there are so many variables in engine builds.

Also note that in the last week or so the use of vacuum advance has been brought up and a discussion about it. Here are my feelings. If it's a street car keep the vacuum advance and tune it like Moper said except I think he made a typo as it's a 11/64 allen wrench used to adjust the vacuum advance canister. If it's a race car you don't need vacuum advance. On a street car it will help fuel mileage and help keep carbon build up down and improve MPG. I recently swapped from a full mechanical dist. to a blueprinted stock type dist. utilizing vacuum advance and my car responded nicely. When it's cold it runs better cause on fast idle it's pulling the vacuum advance giving it more timing when it needs it cold. The cruising mpg went up about 2 mpg. Not a tremendous gain but one that will surely add up. I also noticed the plugs are running a little cleaner. Oh yeah another thing is if you do play with the distributor watch about installing both light weight springs that come in the spring kit as they will make it be at full advance by 1000-1200 rpm which may be too fast for your car and cause spark knock which will destroy the engine fast. Using both light springs can also cause problems getting the carb idle to be stable cause the timing flutters. Just use one light spring and the stock spring that isn't elongated. That'll give you total advance by about 2000-2400 rpm which is about right for a hot street setup.
Click to expand...

Wow . Very good info. So i have had the vacuum capped since day one. Plugs look good, I just changed them with champion (65 heat) and 8mm accel wires to be safe. It is a street car but I race in napa once a month. It is a mp distributor. So install one spring and hook up the vacuum ? I do get ping up hill sometimes. I also think my carb has a partial throttle flat spot. Thanks very much.
 
T67POWER said:
Fish68,
Very well written.:thumblef:
Im glad that you understand the way distributors work and have yours set up for your motor.
The two things i liked most were the fact that you said, not to use the vacume advance on a drag car, and if you do use it on a sreet car to have it blueprinted.
My main concern was people with performance steet motors cranking there timing up and possibly hurting there motors.
The only way to effectivly adjust your distributor to use the vacume advance, is to run it on a distributor machine and adjust the canister to give the right amount of advance for every thousand rpm's.
That is what a blueprinted distributor is.
I ran my distributor i run now in my 318 on my freinds distributor machine and adjusted it to my combination.
It's strickly a mechanical distributer for street racing and bracket racing.
Having acess to a distributor machine is a blessing.

Mopar performance has a book on small block A engines for anybody who dosen't already know ,and it covers every little performance secret that mopar ever found out.:read2:
Click to expand...

Whats the book ? got a link ?
 
green1 said:
Take the dist apart and clean it. Set the initial timing per a vacuum gauge, Then read what the engine wants for initial. then change the mechanical in the dist, to be all in at 2000 or less, and limited to the initial plus whatever to 36 degees+ or-.
Then hook your vacuum advance to ported. You want that 50 degrees that the vacuum gives you at cruise , steady throttle. When you push on the gas pedal, the vacuum advance starts dropping out, as the vacuum in the manifold, and carb(that's why ported) starts dropping. At WOT, no vacuum=no vacuum advance, zero vacuum ; it drops out.
Click to expand...

so ported advance is on left or right side of my edelbrock.
 
fishy68 said:
I have ran into a few things that cause timing to dance around. For one was the bronze oil pump/dist. drive bushing in the block replaced when it was rebuilt? If not it can let the dist. drive flop around and cause the timing to dance. I learned that one the hard way because the first small block I rebuilt yrs. ago I didn't change it on and had that problem. I pulled it back apart and changed it and problem gone. I also ran into a sloppy distributor once (worn bushings) that the timing danced around on. Replaced the bushings and problem fixed. I also ran into one that had a problem in the ECU but it never was a problem until above 4000 so that's probably not your problem although you just never know. As far as the hesitation it could be a lean condition in the carb. How do the plugs look? Is the hesitation worse when the engine is cold? If so it's probably lean and a re-jetting might fix it. Eddy carbs are just fine when jetted properly. Out of the box most carbs need a little touch up because there are so many variables in engine builds.

Also note that in the last week or so the use of vacuum advance has been brought up and a discussion about it. Here are my feelings. If it's a street car keep the vacuum advance and tune it like Moper said except I think he made a typo as it's a 11/64 allen wrench used to adjust the vacuum advance canister. If it's a race car you don't need vacuum advance. On a street car it will help fuel mileage and help keep carbon build up down and improve MPG. I recently swapped from a full mechanical dist. to a blueprinted stock type dist. utilizing vacuum advance and my car responded nicely. When it's cold it runs better cause on fast idle it's pulling the vacuum advance giving it more timing when it needs it cold. The cruising mpg went up about 2 mpg. Not a tremendous gain but one that will surely add up. I also noticed the plugs are running a little cleaner. Oh yeah another thing is if you do play with the distributor watch about installing both light weight springs that come in the spring kit as they will make it be at full advance by 1000-1200 rpm which may be too fast for your car and cause spark knock which will destroy the engine fast. Using both light springs can also cause problems getting the carb idle to be stable cause the timing flutters. Just use one light spring and the stock spring that isn't elongated. That'll give you total advance by about 2000-2400 rpm which is about right for a hot street setup.
Click to expand...

One more question . there is a pretty good speed shop here in town and they tune crab/dist dyno for about 350$. would that be a safe and solid way to go? my builder is all race and made my motor for that. But i do drive it daily . a 13 sec daily driver. Thanks again ps 800 cfm to big for 360 ?
 
If you bought the mopar performance distributor it already has the performance curve.(light weight springs)and your all set.
Timing should not advance any more past 2200 rpms or so.
Set your timing with the timing light and your off.

Remember to rev the motor when you time it.(3000 rpms)

Start at 32 degrees on you timing light and lock the distributor.
You use the 0 on the timing tab to time the car.
You most likely know this ,but i don't like to leave any info. out.
Test drive the car and check for detination.

If you don't think it's having any detination problems then go to 34 degrees.
test drive again and check for detination.
Check a plug if 34 total is feeling good and make sure your not going to lean.

What was your timing at when you were pinging up hills???
Do you run premium gas???

The mopar performance book is part #4876826 by larry shepard
I think they may have a new one out,but i am not sure.
 
pilotsf said:
Wow . Very good info. So i have had the vacuum capped since day one. Plugs look good, I just changed them with champion (65 heat) and 8mm accel wires to be safe. It is a street car but I race in napa once a month. It is a mp distributor. So install one spring and hook up the vacuum ? I do get ping up hill sometimes. I also think my carb has a partial throttle flat spot. Thanks very much.
Click to expand...

If your already getting ping uphill hooking up the vacuum advance will probably only make it worse and destroy your engine so I don't suggest it now. Although if the carb is real lean that can make it ping. I never noticed you saying it is the MP dist. Like T67 said they already have the quick advance so you don't need to mess with the springs.

pilotsf said:
One more question . there is a pretty good speed shop here in town and they tune crab/dist dyno for about 350$. would that be a safe and solid way to go? my builder is all race and made my motor for that. But i do drive it daily . a 13 sec daily driver. Thanks again ps 800 cfm to big for 360 ?
Click to expand...

It's JMO but that'd be the best $350 you'll spend if you know for sure the dyno operator knows what he's doing. I don't think a 800 Eddy is too big. You don't want to go any bigger though. Is that the Thunder series? If so that's a real good carb. Sounds like it's just running lean by your description. If you get the mixture en-richened to where it should be the ping might go away. Try to get that pinging stopped ASAP cause you can beat the pistons and bearings out of an engine in no time if it's spark knocking. I've seen it happen in 150 miles.
 
T67POWER said:
If you bought the mopar performance distributor it already has the performance curve.(light weight springs)and your all set.
Timing should not advance any more past 2200 rpms or so.
Set your timing with the timing light and your off.

Start at 32 degrees on you timing light and lock the distributor.
You use the 0 on the timing tab to time the car.
You most likely know this ,but i don't like to leave any info. out.
If you don't think it's having any detination problems then go to 34 degrees.
Check a plug if 34 total is feeling good and make sure your not going to lean.

What was your timing at when you got pinging up hills???

The mopar performance book is part #4876826 by larry shepard
I think they may have a new one out,but i am not sure.
Click to expand...

Its at 34 now and pings a bit under load. 32 didnt make a difference. I put it at 36 /3000 rpm at the last bracket race . That ok? thanks again !!! 91 octane from76 . Again no vacuum advance hooked up. When I did it seemed worse maybe in my head > Partial throttle lag has to be the carb.
 
The ping is real light up hill only. its the slow partial to full gas pedal when it lags. Awesome JMO
 
fishy68 said:
If your already getting ping uphill hooking up the vacuum advance will probably only make it worse and destroy your engine so I don't suggest it now. Although if the carb is real lean that can make it ping. I never noticed you saying it is the MP dist. Like T67 said they already have the quick advance so you don't need to mess with the springs.



It's JMO but that'd be the best $350 you'll spend if you know for sure the dyno operator knows what he's doing. I don't think a 800 Eddy is too big. You don't want to go any bigger though. Is that the Thunder series? If so that's a real good carb. Sounds like it's just running lean by your description. If you get the mixture en-richened to where it should be the ping might go away. Try to get that pinging stopped ASAP cause you can beat the pistons and bearings out of an engine in no time if it's spark knocking. I've seen it happen in 150 miles.
Click to expand...

Thanks fishy68
 
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