656 Gas Timing

Installed a rebuilt distributor and when I time high idle to 19 degrees the low idle is off... and if I time to low idle at 2 degrees, it won't advance to 19.. rather than chasing springs, is the advance different today based on the lower octane fuel? The specs in the service manual (2 @ 375rpm, 19 @ 2050rpm) were likely tuned for the good gas of the 60s. Any idea if distributors today intentionally don't advance as much or do I have a bad distributor (wrong spring, weight)? I think I am getting approx 10 degrees at high idle
 
Today's gasoline is actually higher octane (regular 87 octane R+M) than the fuel of that era. It is far less likely to foul plugs or create piston and combustion chamber deposits. The rebuilt distributor may have the wrong weight plate in it causing the restricted timing advance described. Look for a number stamped into that plate. Jim
 
(quoted from post at 19:09:52 01/24/23) Installed a rebuilt distributor and when I time high idle to 19 degrees the low idle is off... and if I time to low idle at 2 degrees, it won't advance to 19.. rather than chasing springs, is the advance different today based on the lower octane fuel? The specs in the service manual (2 @ 375rpm, 19 @ 2050rpm) were likely tuned for the good gas of the 60s. Any idea if distributors today intentionally don't advance as much or do I have a bad distributor (wrong spring, weight)? I think I am getting approx 10 degrees at high idle

If you can set it to 19 at high idle and it doesn't ''kick'' against the starter while cranking there's nothing to worry about.
 
Ah NO it's NOT . , read the org. owners manual and it states on the newer 4 and 6 cylinder gas like from 1963 up till the end of the gas engine run on the 66's Minimum of 93 on that scale . Reg gas back then at a regular station around here was 95 and the high test was 105 or better . Now as for his 656 his total timing should be around 23 degrees at high ideal or PTO speed . Only the C 291 timed at 19 degrees . 460 -560 tractors could run on 89 octane and trust me on this they don't like 87 and the 460-560 turn less RPM's and at the moment off the top of my head i can not give you the excite full timing advance on them but it is up in the 20's . Now on his problem i am betting that the dist. he got was set for a C 291 engine not the C 263 . I am one of the few left that knows how to do a dist curve and the only one anywhere around that still has dist strobe . i would say someone has the weight stops set to tight and not allowing them the travel needed to get his timing point. or it is a C 291 unit . when on runs one on the machine you have several RPMS to check advance at and with out digging into the book and the number o the dist. i can't tell what it was set up for or what it came out of . These parts suppliers figure that one size fits all. A C263 in a 560 does not set the same as one used in a 706 . Nor does the same dist work in a C 301 ,l yes they will FIT But they are NOT the same. Will it run yes BUT it will not perform and may cause engine damage.
I have lots and lots of years working on this stuff and over 60 years on dist.
Back in the late sixty's while at a Ford dealer almost one a week someone would come in complaining about Pinging or engine knock with a 390 two BBl , at the time Ford offered two 390 two bl' engines , one was reg fuel rated for the 95 octane the real old gas. then there was the 390 two Bbl Premium fuel and that one required HIGHTEST of 105 OR better , one was a 9.5 to 1 engine and the other was a 10 to 1 engine then ya got into the 4 bbl 390's and not many knew that here again two levels of 390 4 bbl's Ya had the 390 4 v used in the reg. cars then ya had the GT 390 4 v one was a 10.5 to 1 the other was a 10.7 to 1 used in the mustangs and tourino's (sp) they both ran on the 105 BUT would run better on the 250-260 Sunoco gas . Timing curve was a bit faster heads were a little different . Jetting was a little bigger cam was a little better . Things most people did not know . My dad at the time got a 69 Ford galaxy company car and it came with the preme fuel 390 and i had to go thru the same thing with him as he was always CHEAP . He had that car for about a year when the company told him to order in his new car , he had around 30 K on it in a little over the year and had the option to buy that car so he did and it became my moms car , Dad's next one he got the reg. fuel 390 and said that it just did not have what the 69 did and got two MPG less . well dah yea . like a 25 Hp drop in a big old boat of a car. And the R+M way of telling what the gas was was USED BACK them . And what we have now today will NOT run and old performance car from back in the day . And IF your planning on BUILDING a street engine to run on a carb NOW with old school tech. then for get the 10.5 or better pistons and the small CC heads as best ya can do is a 9.5 to 1 on the 93 , oh wait that aint going to work now and so lets drop back to a 9 to1 and cut total advance back to say 34-36 degrees at 2000 and hope it don't PING. . You are sure not going to build a 385 block 460 up to 1970-71 spec's with a 11 to 1 with 72 CC heads and run it on the best pump gas a get today .
 
OOOPPPPPPS I WAS WRONG dang . 656 Gas standard trans does i fact time at 19 Degrees LP times higher High ideal is 2080 Hydo gas times in the 20's I just never worked on that many 656's Worked on a hand full for a local auction company but mainly doing T/A's to get them thru the sale with a working T/A . Some times i do mess up .
 
I marked the outside with tape and degree and the advance is only going 10 or 11 degrees...i need a range of 17. It had a pin stop that sits in a hole in the plate. I think I need to drill this stop hole a little wider on the advance side..being careful to not go too far. I can't see any good numbers on the weights or plates. The distributor is a 368051 R1. At a loss, paid good money for a product that I need to rework.
 
I pulled the distibutor and manually actuated the advance... I marked the outside of the distibutor with tape and degree marks. Only getting about 10 or 11 best case. I need 17 degrees. I think I need to drill the stop hole out a little, with care not to go too far. The distibutor is marked 368051 R1. I don't see any numbers on the weights... or plates.
 
Distributor degrees and Crankshaft degrees are quite different, like 2 to 1 if I remember correctly.
 
You can build a carb engine with 12:1 compression that will run great on pump gas.
I wish my dad was still alive, he bc would give you some education in no time. I used to show him some of your posts and boy would laugh! He thought you were a great comedian!
 
These comments are based on the 4-cylinder distributor. They may not apply.

I believe the part number 368051R1 is the housing, not the complete distributor. Whatever the application and prescribed advance, that part number will still be the same. If differences in the plate determine the max advance, it probably has a number stamped into it that identifies the max advance. If you are going to modify it, at least take a chisel and X out the number.
 
Well then ya had best go tell TRW performance this. also . It was in there BOOKS . Before i close up the shop i had all the up to date engine parts books and THEY had it all laid out . But hay i only build them , and just how many winning engines have to Built . How many factory schools and training session have you completed ?? How many awards did you receive while working at a dealership ?? Personally i received them from Chrysler and Ford . and though i amnot from Mo. you would have to show me just how well you can build a 12 -1 engine and run it on PUMP gas > The engineers at TWR could not do it , you will not even get a 1970 460 Ford to run and it was only a 11 to 1 And even IF you dropped to a 1974 460 you will have problems with it on 93 real gas . You would have to get up into the 80's and now they are down to like and 8.8 compression ratio HUMMMMM . BUT what ever .
 
Look around for and OLD guy that still has a working dist strobe and knows how to use it . More then likely your nowhere close to me . You get in there hacking and wack you can mess it up big time and have no idea of where you end up .
 
Yes, thanks guys. I was about to make a mistake... takes two crank revolutions to turn the distributor once. My degrees were off with my tape. I still have a restricted advance so I will try new plate and springs if I can find them.
 

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