Okay, here it is, searched couldn't find enough info for an answer. I have a ic 392, carter thermoquad, automatic 110,000 on truck. Engine not sure. In an 1980 traveler. Breakerless distrubutor, incomplete California emissions, no smog pump, lines to it are plugged, original huge aire cleaner replaced with open element cleaner, 7 degrees btdc timing, vacuum advance seems to be working, 20" vacuum at 750 rpm, what gives? I bought the darn thing 4 mos ago,drove all the way from scremento, CA in it to tx. Not a single problem, except for detonation in flagstaff, az probbly because of elevation. Po said a tune had been done the day before my arrival and the timing was set "by ear." he did add that it liked premium fuel. I noticed constant detonation on my arrival to texas when I run 87 octane. I have to run 93 octane for it quiet down some. The original plugs in it were champion rj12ycs w/.030 gap. I checked the timing, 15 degrees btdc. Backed off to 7. Helped some. Replaced plugs, opened up to .040 gap rj12ycs, msd blaster 2 coil, little better. Only bandaids. Fooled with the mixture screws on carb, no good. At Jeff's ( of Jeff tech in arlington, tx) suggestion today I replaced them with champion rj14ycs at .030 gap. No detonation at all. Now it idles rough. Good grief. I'm at my whit's end. This truck is almost like brand new, pretty much all original, complete, everything works, etc. Don't know why it has a 392 though. I'm the third owner. Bigger cam maybe the sopurce of my problems? It's a "dressed" ic 392 with CA emissions 345 garb. Is that my problem. Help please! Sorry for the incredibly long post. Lots of problems... Oh yeah, it get's 7 freekin mpg at 60mph. Figured I'd get at least nine with 3.54s and 31s
IC 392 BAD Mileage, mistery detonation/pinging
- Thread starter cbmind
- Start date
Not sure what all your problem(s) are ... But,
high elevation (flagstaff) does not cause detonation. Generally, you can advance the timing at high elevation more than you can at sea level -- if you live there. If you "look closely" you will find it hard to find a gasoline "rated" over 89 octane in flagstaff or other "high altitude" cities -- I think the chevron pumps are 85 / 87 / 89 instead of 87 / 89 / 91.
There are a number of causes of detonation (and michael mayben can supply more / correct my list) -- timing too far advanced / not high enough octane fuel / "heat" (mixture too lean?) / "hot spots" in the combustion chamber.
What does "dressed" mean? -- rebuilt? Highly modified?
Imho, rj14 plugs are "too hot" -- I am currently using ac r43s in my 392 -- but, my 392 is stock, original, CA smog functional.
I would back off the timing more - to 4btdc or even tdc.
And, maybe even have a compression check done.... If the engine has been rebuilt; maybe the compression ratio has been raised too high.
Afaik, no travelers (or scouts) came with a 392, so a po put it in there.
high elevation (flagstaff) does not cause detonation. Generally, you can advance the timing at high elevation more than you can at sea level -- if you live there. If you "look closely" you will find it hard to find a gasoline "rated" over 89 octane in flagstaff or other "high altitude" cities -- I think the chevron pumps are 85 / 87 / 89 instead of 87 / 89 / 91.
There are a number of causes of detonation (and michael mayben can supply more / correct my list) -- timing too far advanced / not high enough octane fuel / "heat" (mixture too lean?) / "hot spots" in the combustion chamber.
What does "dressed" mean? -- rebuilt? Highly modified?
Imho, rj14 plugs are "too hot" -- I am currently using ac r43s in my 392 -- but, my 392 is stock, original, CA smog functional.
I would back off the timing more - to 4btdc or even tdc.
And, maybe even have a compression check done.... If the engine has been rebuilt; maybe the compression ratio has been raised too high.
Afaik, no travelers (or scouts) came with a 392, so a po put it in there.
Some more "thoughts" --
first off -- do you have more history on the motor? Did the person you bought the vehicle from rebuild it? "how" was it rebuilt? -- "stock"? Or "modified"?
Gas mileage (and drivability) --
I think that the carter thermoquad May be the original 4bbl that came on the 345 (it seems this was the stock engine for your vehicle). Did the "rebuilder" just transfer the 345 4bbl manifold / carb to the 392?
Imo, if this is the stock 4bbl carb for the 345, it is "too small" for a 392. 392's came with Holley carbs -- in the 600 cfm range. Your carter is probably a 350cfm.
You need to supply the numbers on the carb for someone (mm) to be able to tell for sure which carb it is (350cfm / 600cfm).
If it is a 600cfm carb, it probably needs to be rebuilt or replaced.
There is a lot of info on IH carbs in the carb tech forum....
Valve train noise --
this indicates oil not getting to the "top" of the engine -- there are a number of "issues" -- improper installation of the rocker arm assemblies is one.
Michael mayben has posted extensive info on "valve train problems" on this forum...
I do not know how you got detonation at a high altitude. Was it actually pre-ignition? (though, if it was; I do not think the motor would still be running.... Even though IH motors are really tough...)
and, I do not understand how a "higher heat range" plug "cured" your detonation???
first off -- do you have more history on the motor? Did the person you bought the vehicle from rebuild it? "how" was it rebuilt? -- "stock"? Or "modified"?
Gas mileage (and drivability) --
I think that the carter thermoquad May be the original 4bbl that came on the 345 (it seems this was the stock engine for your vehicle). Did the "rebuilder" just transfer the 345 4bbl manifold / carb to the 392?
Imo, if this is the stock 4bbl carb for the 345, it is "too small" for a 392. 392's came with Holley carbs -- in the 600 cfm range. Your carter is probably a 350cfm.
You need to supply the numbers on the carb for someone (mm) to be able to tell for sure which carb it is (350cfm / 600cfm).
If it is a 600cfm carb, it probably needs to be rebuilt or replaced.
There is a lot of info on IH carbs in the carb tech forum....
Valve train noise --
this indicates oil not getting to the "top" of the engine -- there are a number of "issues" -- improper installation of the rocker arm assemblies is one.
Michael mayben has posted extensive info on "valve train problems" on this forum...
I do not know how you got detonation at a high altitude. Was it actually pre-ignition? (though, if it was; I do not think the motor would still be running.... Even though IH motors are really tough...)
and, I do not understand how a "higher heat range" plug "cured" your detonation???
7 mpg in a traverler does seem to be a bit on the low side.
My '74 200 4x4 with 392/727, 4.10 gears, and 9.50x16.5 tires I got 8.5 mpg.
Having the 11' camper on or off didn't make any real difference in fuel consumption.
What made a big difference, particularly when the camper was onboard, was trying to cruise at 70+ mph. That would really suck the fuel down. Down as into the 5-7 mpg range.
With a vehicle with a smaller brick appearance and a much lighter weight you should see quite a bit better fuel mileage, particularly if you have faster gears.
Going to skinnier tires can help a lot as well.
Knowing what your manifold vacuum is while you are cruising can help determine why you are using so much fuel. Less than 10" would mean you are into the secondaries a lot. Which would also tend to overfuel your truck. Which would also tend to lead to some driveability issues.
My '74 200 4x4 with 392/727, 4.10 gears, and 9.50x16.5 tires I got 8.5 mpg.
Having the 11' camper on or off didn't make any real difference in fuel consumption.
What made a big difference, particularly when the camper was onboard, was trying to cruise at 70+ mph. That would really suck the fuel down. Down as into the 5-7 mpg range.
With a vehicle with a smaller brick appearance and a much lighter weight you should see quite a bit better fuel mileage, particularly if you have faster gears.
Going to skinnier tires can help a lot as well.
Knowing what your manifold vacuum is while you are cruising can help determine why you are using so much fuel. Less than 10" would mean you are into the secondaries a lot. Which would also tend to overfuel your truck. Which would also tend to lead to some driveability issues.
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
Robert is correct regarding his "altitude" analysis.
This engine begs for "diagnosis 101" in the worst way!
I'm surprised that "Jeff/jefftech" didn't suggest that, the plug heat range is just one tiny piece of this deal and that is after all other engines systems are diagnosed/verified...he knows that! And yes...I have delt with him, by telephone, in the past regarding a very high end 345 he built for a friend but then had issues with drivability and "tuning". I talked jefftech through what to do, that was several years back.
By the way, my "home" is grapevine and yes...I do go back far enuff in the dfw area to remember when fm 157 (collins) was a gravel road between grapevine and arlington.
First off...unless the "po" was either me or one of the Ismail boys, ya can't trust anything they might tell ya about IH schnizz! And Chad is trustworthy also! The two roberts are still on probation but so far they will soon join the elite!
And...the pull between kingman, az and flagstaff,az is the longest, continuous grade (but not most severe) in the continental u.s. And is an excellent test of engine drivability/performance, most especially if the vehicle is heavily loaded. I drive that route fairly often in IH stuff and have for over 40 years in other rigs of all kinds, though I greatly prefer route 66.
Unless the compression ratio on this motor was grossly "over-corrected" when built, there is no need to run any grade fuel other than what might pass for today's "regular", as shitty as it is since it's e10.
No 392 running "regular" can run more than 6>7* base timing with a perfect distributor between sea level and about 3500ft. Elevation, don't care how the carb is set up. A 304/345 May tolerate up to 12*btdc, especially above 4,000ft.
I'm also suggesting that the distributor you are attempting to run is not correctly set up for proper advance curve, most definitely if the egr system has been eliminated. Identify the distributor for us and we can tell ya more info about that, need the part number!
If diddlin' the idle mixture screws don't make any difference in idle quality, then ya got carb issues also!
So bottom line...ya need to do/have done a major "tune up" by someone who is at least 50 years old and worked on IH stuff before! Then they can advise what needs attention.
We got tons of detailed "how-to" diagnostic stuff here in this forum, do some homework and get back to us!
Try these threads for starters:
http://www.forums.IHPartsAmerica.co...I-4-sv-engine-non-oiling-rocker-assembly.html
And:
http://www.forums.IHPartsAmerica.com/ignition-tech/642-ihc-vehicle-distributor-identification.html
And:
http://www.forums.IHPartsAmerica.com/carb-tech/1343-carter-thermo-quad-replacement.html
And this one:
http://www.forums.IHPartsAmerica.com/gas-engine-tech/1016-waynes-non-oiler-392-a.html
Wayne's motor was pro-built and they tried to blame the "issues" on the new carburetor! Just five days ago, I had the same machine shop do a "bake and blast" onna Ford 390 fe block only and they scruud that up too! But at least they were able to do the magnaflux process correctly and found one insignificant crack!
Same thing as advised in several other threads around here...do a compression test sequence followed by a leakdown test. Only then do ya move on to first ignition and then lastly, carburetion.
This engine begs for "diagnosis 101" in the worst way!
I'm surprised that "Jeff/jefftech" didn't suggest that, the plug heat range is just one tiny piece of this deal and that is after all other engines systems are diagnosed/verified...he knows that! And yes...I have delt with him, by telephone, in the past regarding a very high end 345 he built for a friend but then had issues with drivability and "tuning". I talked jefftech through what to do, that was several years back.
By the way, my "home" is grapevine and yes...I do go back far enuff in the dfw area to remember when fm 157 (collins) was a gravel road between grapevine and arlington.
First off...unless the "po" was either me or one of the Ismail boys, ya can't trust anything they might tell ya about IH schnizz! And Chad is trustworthy also! The two roberts are still on probation but so far they will soon join the elite!
And...the pull between kingman, az and flagstaff,az is the longest, continuous grade (but not most severe) in the continental u.s. And is an excellent test of engine drivability/performance, most especially if the vehicle is heavily loaded. I drive that route fairly often in IH stuff and have for over 40 years in other rigs of all kinds, though I greatly prefer route 66.
Unless the compression ratio on this motor was grossly "over-corrected" when built, there is no need to run any grade fuel other than what might pass for today's "regular", as shitty as it is since it's e10.
No 392 running "regular" can run more than 6>7* base timing with a perfect distributor between sea level and about 3500ft. Elevation, don't care how the carb is set up. A 304/345 May tolerate up to 12*btdc, especially above 4,000ft.
I'm also suggesting that the distributor you are attempting to run is not correctly set up for proper advance curve, most definitely if the egr system has been eliminated. Identify the distributor for us and we can tell ya more info about that, need the part number!
If diddlin' the idle mixture screws don't make any difference in idle quality, then ya got carb issues also!
So bottom line...ya need to do/have done a major "tune up" by someone who is at least 50 years old and worked on IH stuff before! Then they can advise what needs attention.
We got tons of detailed "how-to" diagnostic stuff here in this forum, do some homework and get back to us!
Try these threads for starters:
http://www.forums.IHPartsAmerica.co...I-4-sv-engine-non-oiling-rocker-assembly.html
And:
http://www.forums.IHPartsAmerica.com/ignition-tech/642-ihc-vehicle-distributor-identification.html
And:
http://www.forums.IHPartsAmerica.com/carb-tech/1343-carter-thermo-quad-replacement.html
And this one:
http://www.forums.IHPartsAmerica.com/gas-engine-tech/1016-waynes-non-oiler-392-a.html
Wayne's motor was pro-built and they tried to blame the "issues" on the new carburetor! Just five days ago, I had the same machine shop do a "bake and blast" onna Ford 390 fe block only and they scruud that up too! But at least they were able to do the magnaflux process correctly and found one insignificant crack!
Same thing as advised in several other threads around here...do a compression test sequence followed by a leakdown test. Only then do ya move on to first ignition and then lastly, carburetion.
Dealbreaker74
Member
Thermoquads' cfm ratings were much higher than the holleys ihc used. At least 800 cfm, and possibly 850 depending on the exact model. They came standard on 345s, and mopar 340s and 440s. 800 cfm is more than adequate for a 392. The carb May still need help, but lack of cfm is not his problem. As michael stated, there is a laundry list of things causing this pain. A systematic diagnosis of the engine history, mods made during rebuild (cam?), and reliably verifying compression would be a huge help.
I doubt IH put a 800cfm carter on a stock IH engine.
800 cfm carters were stock on dodge / mopar 440s -- a completely different engine...
You (and michael) are correct the engine / ignition needs to be checked out.
Putting a "new" carb on an engine with other problems will not fix the problems....
800 cfm carters were stock on dodge / mopar 440s -- a completely different engine...
You (and michael) are correct the engine / ignition needs to be checked out.
Putting a "new" carb on an engine with other problems will not fix the problems....
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
The root source of this engine needs to be verified. It May not even be a 392, and if it is, which variation.
A 392 inna '74/'75 pickup or t'all could very well have had a thermoquad/spreadbore intake as oem. I have n=2 tq carbs for pickalls here right now. That was an "emissions" transition setup and accompanied by an introductory "service letter" of nearly forty pages. And then of course, those platforms went away though there May be some "titled" as a m/y 76. 35+ years gone and there is no tellin' how all this stuff has been swapped around under the hood.
If the motor came from a medium duty truck, it still had a Holley 4150/4160 squarebore or even a "governed" Holley 4150 squarebore.
And the oem calibration setup for the tq onna 392 as compared to a 345 is nearly identical.
This problem is not carb-related until proper diagnostics are completed. If diagnostics point to carburetion, then that can be easily delt with.
A 392 inna '74/'75 pickup or t'all could very well have had a thermoquad/spreadbore intake as oem. I have n=2 tq carbs for pickalls here right now. That was an "emissions" transition setup and accompanied by an introductory "service letter" of nearly forty pages. And then of course, those platforms went away though there May be some "titled" as a m/y 76. 35+ years gone and there is no tellin' how all this stuff has been swapped around under the hood.
If the motor came from a medium duty truck, it still had a Holley 4150/4160 squarebore or even a "governed" Holley 4150 squarebore.
And the oem calibration setup for the tq onna 392 as compared to a 345 is nearly identical.
This problem is not carb-related until proper diagnostics are completed. If diagnostics point to carburetion, then that can be easily delt with.
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Robert Kenney
Super Moderator
We need to reign in the info here. Set up a series of logical tests and evaluations for cbmind to follow.
Like mm wrote". The root source of this engine needs to be verified."
ya'll have some good ideas for sure. But they need to be placed into ihon form circulation "after a methodical series of diagnostic steps are gone through. We can't simply stab at the possible cause until the process indicates the next step. These tech form are for solving problems and cbmind has some definite issues he needs help solving. I don't mean to step on anybodies toes here, so please don't take offence to what I have written and we appreciate eveybodies input
we need to reign in the info here. Set up a series of logical tests and evaluations for cbmind to follow.
Would like to have cbmind read and post as many answers to our questions as possible so we can get started helping.
Thanks
rk
Like mm wrote". The root source of this engine needs to be verified."
ya'll have some good ideas for sure. But they need to be placed into ihon form circulation "after a methodical series of diagnostic steps are gone through. We can't simply stab at the possible cause until the process indicates the next step. These tech form are for solving problems and cbmind has some definite issues he needs help solving. I don't mean to step on anybodies toes here, so please don't take offence to what I have written and we appreciate eveybodies input
we need to reign in the info here. Set up a series of logical tests and evaluations for cbmind to follow.
Would like to have cbmind read and post as many answers to our questions as possible so we can get started helping.
Thanks
rk
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
Remember robertc...in that era...it was all about "emissions" and meeting targets for the feds. Nobody gave a dam about drivability, that was for the dealer mechanics to fight out the solution and finish buildin' tha rigs so the customer didn't try and place it where the sun didn't shine on the service manager's azz!
Yore t'all was one of the last of the "good ones"!!
Dealbreaker74
Member
wow, thanks guys! I'll try and answer as best as I can:elevation here in cleburne, tx is 550'.
The traveler gets driven regularly
I don't know what to call it, detonation, pinging, whatever, higher pitched noise that sounds like rattling at part throttle
dressed meaning it is a verified 392. Stamp is v392 on passenger side boss at front of block. Ic, water tubes go back to the block, not the heads. It has a 4brl spreadbore intake manifold. All emissions equipment was intact when purchased and in working order. Air pump, bracket have been removed. Egr is in place, plumbed correctly.
Rj 12ycs were in it when I bought it. I replaced them with same, gapped to .035. No bueno. Still rattling at part throttle and poor mileage on low octane fuel. Jeff at Jeff tech recommended rj14ycs gapped tight @.030". He looked it over thoroughly when I brought it to him 3 mos ago. When I visited him in person on Monday, he was tied up with another project and recommended the plug change after I described my problems. I take Jeff to be an honest person, I've been doing business with him for 10 yrs, the uy knows his stuff. He takes care of many a binder in north texas for several people.
I am the third owner, the one before me swears he didn't touch the engine as far as swapping or rebuilding it, all work was handled by a mechanic in fresno.
I will check tomorrow for the numbers on the carburetor
I don't know if the higher heat range actually "cured" anything, all I know is the tin can symphony is silent at part throttle.
I don't know the cruisong vacuum, vacuum, warmed up, vacuum advance connected (if it matters) @800rpm,is 20". Fluctuates slightly, but an insignificant amount (.5"?)
if I'm still having problems, I'll have to take it Jeff next Monday, he's booked the rest of this week.
I have not done a compression check, will tomorrow. Just one cylinder, or all eight?
I'll read the article on dizzy id and get the part number tomorrow as well
I emailed the previous owner with several questions, hopefully I'll hear from him soon.
Thank you everyone for the information, great resource, I appreciate it. People like y'all that make fixing something almost as old as me almost tolerable and borderline enjoyable
Robert Kenney
Super Moderator
Good start to the info we need to form a plan.
A compression check is very valuable here. It gives us some insight of your dynamic compression. That takes into account the cam and cam timing along with your built in compression ratio.
If you are unsure how to check your compression let us know. It would be best to do all eight cylinders. And write the numbers down.
Next would be total timing. That is basically when running in park at a rpm high enough to allow the mechanical or centrifugal to fully come in (lets say @ 3000 rpm) how much advance is set in. I would like to see 34-36 degrees max for now. You will need a timing light with the timing knob or setting. This is done with the vacuum advance disconnected. Again we can walk you through it if you would like.
If you have a digital camera some clear pictures will help greatly. Try to get the vacuum hose routing from all 4 sides of the engine.
This is a good start and will ultimately pay off when your IH is playing nice.
Robert
A compression check is very valuable here. It gives us some insight of your dynamic compression. That takes into account the cam and cam timing along with your built in compression ratio.
If you are unsure how to check your compression let us know. It would be best to do all eight cylinders. And write the numbers down.
Next would be total timing. That is basically when running in park at a rpm high enough to allow the mechanical or centrifugal to fully come in (lets say @ 3000 rpm) how much advance is set in. I would like to see 34-36 degrees max for now. You will need a timing light with the timing knob or setting. This is done with the vacuum advance disconnected. Again we can walk you through it if you would like.
If you have a digital camera some clear pictures will help greatly. Try to get the vacuum hose routing from all 4 sides of the engine.
This is a good start and will ultimately pay off when your IH is playing nice.
Robert
For total timing, what is "timing setting or knob" reference to? Is that supposed to be a readout on the timing light itself? The only kind of timing light I have is the regular inductive timing light, no readout. Can you explain further? Thanks for the help, some times I'm ignorant, I have moments...
Robert Kenney
Super Moderator
Basically the timing setting or knob is an adjust ability built in to an inductive timing light similar to the one you already know and use. Some are a knob and some are a digital read out that usually includes the ability to indicate rpm. This allows you to delay the strobe flash the dialed in number of degrees so the "0" timing Mark on the cover can be used in conjunction with the Mark on the front crank balancer.
Let's say the adjustment on the timing light is set to 36 degrees and while applying the timing light and after increasing engine until the timing marks stop moving(advancing) the "0" Mark and the balancer Mark line up. This means you have 36 degrees of total timing. That would be spot on and no ping or knock should be heard if all other conditions are ok. Remember to do this timing routine with the vacuum advance line disconnected and plugged.
Robert
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Okay, just wiped the grime off my fingers so I could tickle the ivories... Here's the results of my compression check:
ding ding ding!!!
Cylinder number 1 coming in at- 152
cylinder number 2- 158
cyl 3- 149
cyl 4- 152
cyl 5- 153
cyl 6- 152
cyl 7- 152
and in this corner!!! Cylinder number 8!!! At you ready??? 160!!!
All this on the basic brand new equus diagnostic compression checking apparatus.
Trying to find a place right now that will check my timing. Get back to y'all asap. All numbers I'm guessing are +/- 1.thanks
chris.
ding ding ding!!!
Cylinder number 1 coming in at- 152
cylinder number 2- 158
cyl 3- 149
cyl 4- 152
cyl 5- 153
cyl 6- 152
cyl 7- 152
and in this corner!!! Cylinder number 8!!! At you ready??? 160!!!
All this on the basic brand new equus diagnostic compression checking apparatus.
Trying to find a place right now that will check my timing. Get back to y'all asap. All numbers I'm guessing are +/- 1.thanks
chris.
Robert Kenney
Super Moderator
Those look ok assuming you had the throttle open some.
You should be ok to have 34- 36* max of total timing running on regular pump gas of 87 octane.
The 160psi is suspicious and a tad high for an 8-1 compression motor camed up a bit sounds more like 9-1. But should still be ok.
Next time you drive the bad boy disconnect the vacuum advance diaphragm and plug the carb port. See if the ping is still the same. Just an other point of info.
Rk
You should be ok to have 34- 36* max of total timing running on regular pump gas of 87 octane.
The 160psi is suspicious and a tad high for an 8-1 compression motor camed up a bit sounds more like 9-1. But should still be ok.
Next time you drive the bad boy disconnect the vacuum advance diaphragm and plug the carb port. See if the ping is still the same. Just an other point of info.
Rk
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Happy that my compression psi worked out good, really think it's a good engine with a lot of potential. Took it to rick's auto in cleburne where I live, had to go to three different places to find an old car friendly mechanic shop. Thanks rick's. Big help,
to the other shops. It was cars like this till 20 yrs ago that were paying your bills on a regular basis... Anyway here's the results.
With vacuum advance disconnected, timing at idle is 10, at 3000rpm, 20.
With vacuum advance connected still 10 at idle (750rpm) and 45 (!) at 3000rpm.
Now, what do I do with this inf?. Sounds like it might need to be adjusted a tad... And maybe I need to open my eyes wider, I thought it was at 7 before. Oh well...
Is the 10 degree spread running with vacuum advance disconnected normal?
Is the 35 degree spread with it connected normal?
What should I adjust it to?
By the way, the 152 +/- 1 psi equates to around 10 on kpa. Thinking kpa means kilopascals. What does 152 equate to in compression ratio?
Thanks
to the other shops. It was cars like this till 20 yrs ago that were paying your bills on a regular basis... Anyway here's the results.With vacuum advance disconnected, timing at idle is 10, at 3000rpm, 20.
With vacuum advance connected still 10 at idle (750rpm) and 45 (!) at 3000rpm.
Now, what do I do with this inf?. Sounds like it might need to be adjusted a tad... And maybe I need to open my eyes wider, I thought it was at 7 before. Oh well...
Is the 10 degree spread running with vacuum advance disconnected normal?
Is the 35 degree spread with it connected normal?
What should I adjust it to?
By the way, the 152 +/- 1 psi equates to around 10 on kpa. Thinking kpa means kilopascals. What does 152 equate to in compression ratio?
Thanks