fuel mileage and performance

hotrodguy

Well-known member
I have a 65 Ranchero, 200 -6. 68 Mustang dizzy recurved with with softer springs, I bent 1 tab on the spring to increase the mechanical advance. I ru about 14 degrees initial advance. Autolite 1100 with the spark control plugged off, run ported advance , rejetted the carb from 56 down 50. Number 1 and 6 plugs 1 range cooler , all plugs light tan. Runs very clean, timing set for no ping on a hill. Fuel mileage at steady 65 on highway about no better than before all this change. Car still feels somewhat sluggish. All I can figure is that I still do not have enough mechanical advance. What do the experts say? Thank you.
 
Stock ignition on these engines gives you up to a 15% misfire rate. If you use an electronic ignition, you will notice an immediate jump in performance and economy. I used the Pertronix and have had no problems. Other guys use the Duraspark system. Easily salvageable for next to nothing or buy all the parts new for under $200 at the auto parts store.
 
i agree with ludwig, personally i would step up and pop for one of wsa111's recurved distributors.
 
ok, that still does not change my recommendation. wsa111 puts his distributors on a distributor machine so he knows what the advance curve truly is, rather than just dropping some lighter springs and hoping for the best.
 
I had a mechanic recurve it on a machine before it was installed. He used the info from the I -6 performance book.
 
I can recurve your distributor with the pertronix for $75.00 plus parts & shipping.
Your best bet is purchase one of my distributors & either install a Duraspark box, GM module or better yet install a MSD box & a MSD harness which connects the DS11 to the MSD.
You need more carburation & pick up a Carter YF from a 69 250.
You will to adapt the larger throttle bore to your intake.
You really need a D-E head to really gain some power. The stock camshaft is also a looser.
I can tweek your distributor a little which will help, but don't expect miracles. Bill
 
wsa 111 , thank you for your recommendations, this car is my daily driver, hi way cruiser. When I kicked up the initial timing to 20 degrees and blocked off the ported vacuum ,it ran much better but mileage dropped way off. From this, is why I suspect I need more mechanical advance and probably back off the initial timing to 8- 10 degrees. Just looking to make the most with a stock engine. My 62 Ranchero , I am building, will be a drag race car only, 69 250 6 turbocharged on E-85. I am just beginning to do the head work. My engine builder recommends to run a crank trigger with this one, and I will. Time to have some fun, running sportsman and whipping some of those bent bow ties. This is a great site, I'm happy I found it. Randy
 
Howdy Randy and all:

A few questions- You said you are running an 1100 with the SCV port blocked off. Where are you sourcing from? Is this carb from a Calif. car? Is this distributor a dual advance/retard distributor? How Many degrees of advance are you getting from the centrifugal advance? What is you elevation?

FYI- Bill, the '69 250 carb is an Autolite 1101 but it will NOT have a SCV and will have a ported vacuum source. So, Randy, if you have a builder '69 250, did you get the carb too? Bingo!

Keep it coming.

Adios, David
 
Hi David, Calif car , porting from the outlet on the middle of the carb. I am running about 14 degrees initial, on the centrifugal advance I do not know the advance, single vacuum advance, elevation 1400 feet. The 69 engine is totally seperate (sp) from this one, no carb with it. When I talked with the carb shop in Sacramento the fellow said the 1100 and 1101 were the same except for the spark control valve. The 69 will be strictly drag race and I plan to use the $600 Holley e-85 carb. Will in Tucson said use it and avoid headaches down the road. Thank you, Randy
 
Howdy Back Randy:

FYI- the 1100 and the 1101 are not the same. While they appear the same externally, they are quite different inside. The 1100 came in several CFM sizes and had SCV, but in '66 & '67 CalifEm equipped cars used an 1100 with no SCV but had a ported vacuum source. the highest cfm rated 1100s were 185, while all 1101 were rated at 210 cfm. 1963 &'64 Fords with 223 sixes came with an 1101 with SCVs. The 1969 Mustangs with 250 engines came with an 1101 without SCVs. So, ideally, you'd be doing yourself a favor if you could source an 1101 from a 1969 Mustang with a 250 engine. It would have the correct ported vacuum advance source for your distributor and increased CFM for more power.

That said, I'm thinking there is a mismatch between your carb and the distributor vacuum and centrifugal advance systems. When you modded the centrifugal advance system did you plot the advance curve before and after to know how it changed? What rpm does centrifugal advance begin and what rpm is it all in? The same should be known about the ported vacuum source, as well as the amount of vacuum advance in the distributor. Inches of vacuum vs degrees of advance.

I sure like the sound of your 250 project. Keep it coming.

Adios, David
 
David, I had a local shop do the recurve change, he did not plot the before and after, but he had a copy of your book information to follow. The springs were changed with the Mr. Gasket springs as per your recommendation. concerning the little hole in the dizzy breaker plate, I bent the spring tab a bit and this improved things some, but for some reason the spring disappeared, moved under the breaker point. Something tells me if I could bend the tag some more it would improve even more. Is it possible to get too much centrifugal advance? My car is a 65 , likely the carb is a 185cfm. I can find a 69 1101. Do you suspect the fuel mileage is not good because of the advance problem? I will keep you posted on the 250 project. Thanks Randy
 
Randy, the spring came off the adjustment tab. Thus your centrifugal advance is way off & probably affecting your attempt to properly set your initial advance.
I am not bad mouthing the tech who did the recurve, but you need someone familiar with the ford distributor spring settings & design. Bill
 
Hey Randy:

That bend on the mounting tab is for a DuraSpark II distributor. It is 3/32". I don't know what it should be on a '68 points distributor. If the spring fell off the advance will only be controlled by the remaining spring. It will probably come in too fast and fall back slowly. The mechanical advance is limited by the weights so it can't be too far off. If you can, bend the mounting tab back far enough to securely maintain the spring. then plot to determine what rpm advance begins, and what rpm it maxes out at and how many degrees are added.

keep it coming.

Adios, David
 
Randy, it would be highly recommend to have your distributor fixed correctly.
Tab specs are just a starting point for your distributor curve.
David gave you the basic guide lines.
Apparently you don't want to spend the money to get your distributor fixed properly.
You're choice.
 
Thanks Guys, I have a local guy with a distributor machine , he set the dizzy up initially using David's book. This car is my daily driver so I need to get this work done here. My gut on all this is I still do not have enough mechanical advance. I could be wrong. The 1 time I plugged the vacuum advance and gave it 20 degrees initial it ran so much better, it was running rich before rejetting and this is when mileage really fell off. If I go to a 1101 carb does Will have the manifold adapters, I understand his parts inventory is limited. I do not expect a high performance engine just make this run as efficiently as possible.
 
I am not qualified to offer any suggestions but I can say my DSII ignition sourced as usual from picnpul on half price day performs great and hasn't even been custom curved yet. Also Rancheros are one of my favorites, a friend got one recently and he has it looking pretty good.
I am curious about using a cooler plug on 1 and 6, I know 1 runs cooler and six hotter so how is this working out for you? I have not heard of this before and not trying to sidetrack your thread.
 
Howdy Back all:

Hotrodguy- On mounting a 1101 on your '65 200, you can get by without an adaptor by filing the inner top edge of the adaptor under your stock 1100 adaptor enough to clear the larger butterfly valve of the 1101. Mounting bolt spacing is the same at 2 5/8". Fuel line and linkage need no adapting. Even your stock air cleaner works. This was one of the earliest mods I did to my '65 200 Roo. It rocks! I didn't rejet or anything else. Just a little tuning on the air screw, choke and initial timing. Life was simpler back then.

bmbm40- The rationale for using cooler heat range plugs on 1 & 6 is based on the belief that they are farthest from the center mounted carb and therefore run leaner. But proximity to air and water cooling mitigates that thought. Cylinder #1 is closest to the water pump and fan causing it to run somewhat cooler then cylinder #6. #6 is farthest from cooler air and water pump cooled water. It is also somewhat shrouded by the firewall and everything else in the engine bay. My experience was that #6 ran hotter. There are too many variable to say yea or nay to a one-size-fits-all answer or generality with this issue. The only way to tell is to experiment on an engine. No two engines will be the same. So, if it works for you, in your situation, as born out by plug reads then it works. There is no rule that says you must use the same spark plug in all cylinders.

Keep it coming.

Adios, David
 
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