timing and gap

[havoline]

Brakes are new, front discs rear and in good shape, just been bled, tires are at minimum 35psi.

Engine feels like I have to give it more rpm to move.

No vacuum leaks, need to replace spark plugs though.

But again my mpg is not what is should be. I was getting 25 mpg on highway before headers, now getting 22. And in the city is a joke. When I go to LA next week I will know for certain if the new ignition system has paid off but if it hasn't any suggestions?

 

[CZLN6]

Howdy Back Havoline:

Just to review, do I recall correctly, did you install a DUI distributor? What is your current initial advance setting? Are you still using the original Autolite 1100 carb? What is the gear ratio on the V8 rear end? How long has it been since the carb has been rebuilt?

FYI, the 8.8 rear end will use more power to turn than your original rear end. In general, the least amount of choke, accelerator pump and idle speed possible is always a good idea when searching for MPG. Those things matter most is city mileage and cold start-up.

Assuming you have the OEM carb and the DUI distributor, you have a vacuum advance mismatch. The mismatch can be compensated for by adding more initial advance, but it will never be righted. The best solution will be to update your carb with a Carter YF carb that has a ported vacuum source for the distributor.

Your driving style sounds like you are on target for good MPG.

Finally, has the head been worked on at all? more specifically, what is the compression ratio of your engine?

Keep it coming.

Adios, David

 

[havoline]

Yes and it is set at 12 bdtc. And is at 24@3000rpm set by performance distributors. Engine is mainly stock otherwise.

Yes still using autolite. It is a at least 6 years old on the car. And have been thinking of replacing carb with either universal carb from classic inlines or going with a two barrel but again I am tired of throwing away money with no results. Yes I have a 8.8 rear ends but that has not changed since I have had the car and years ago I was getting when driving carefully over 20mpg city 25-26 mpg highway with only pertronix ignition and coil and flowmaster muffler only.

I can try adjusting the timing abit more.

As well as get new spark plugs but what would be recommended for my new ignition? Also would this new system allow my car to run colder?

Compression ratio is 9.2:1. Head is stock.

Either I replace it with a better one barrel carb or a two barrel or I get rid of the headers since they haven't done a thing for me besides just look nice.



Also how do I edit my signature at the bottom it's out of date now?

 

[Econoline]

When was this motor last overhauled? Have you done a compression and leakdown test on it? How do you know you are @ 9.2:1 SCR? An old motor with worn out valve guides/seats, stretched chain and worn rings in oval holes isn't going to run like a new one or get great gas mileage no matter what you do otherwise.

Yes, ditch that POS 1100. You've already updated the ignition, a new or old YF or universal or used RBS, whatever.

 

[CZLN6]

Me again:

At a minimum, it's time for a carb rebuild. Or an upgrade. If you want a bolt on that will match the vacuum needs of the DUI, I'd recommend an Autolite 1101. It will look and hook-up the same as your 1100 but increase CFM from 185 to 210- a noticeable difference. You will need to taper to the inlet hole to allow the larger butterfly to open. This carb is a little scarce, but look for a 1101 from a 1969 Mustang with a 250 engine. It was used one year only on 250 engines. It was replace in 1970 by the Carter RBS- a totally different looking carb, but also a choice for upgrading.

Another one barrel option is a Carter YF. It will require some adaptation of mounting, linkage, fuel line and air cleaner. It came on 170, 200 and 250 engines so make sure you get at least a 200 size carb. It was also used on the big sixes- 240 and 300s.

The two barrel option is the Holy Grail, but the most expensive and requires the most adaptation. It might be a better option if/when you have the head off for a rebuild. It might be worth the time and trouble to follow Econolines suggestion to check cylinder pressures just to be sure you are not chasing the wrong problem.

Lastly, I'd suggest that you play with the initial advance at 14 and 16 degrees. If you get pinging you can always retard it a bit. Fresh plugs are always a good idea. Gap a .050" with the DUI and check them periodically noting changes and differences between cylinders.

My guess is that the current mismatch between carb and distributor vacuum advance is hurting your quest for mileage. For best results get them married up.

Good luck and keep it coming.

Adios, David

 

[havoline]

again I am just feeling like I have been wasting my money and time doing all of this....everyone keeps saying and posting ideas that this works on these cars but I dont see that at all.

I put fresh plugs, gapped at .055 set at 12 btdc and the car has no throttle/acceleration at low speeds. no low end torque. and it is decreased since changing from stock distributor for certain. and my carb is a 1101. I rebuilt my carb a couple of years ago so I know its good. or at least good for supposed to be stock. my sparl plugs mainly came out red meaning rich but I cant get the mixture any lower and I know its been overheating abit even with my aluminum radiator and I have no air bubbles in the system.

I am sure I do need to marry them up but is that possible with my current or any other carb with the DUI or am I screwed? All will be tested tomorrow when I go down to LA and if I can even get over the grapevine. If I get less than 22 mpg I am going to flip out cause that is what I got last time going to and from LA on the highway. The whole point in my mind about these cars and engines to justify having was to be not so hard on the wallet and the fact that they can go without having to be a V8.

Im really starting to hate my headers, and the fact that they are classic inlines bothers me since I paid alot, the nuts that came with kept falling off, finish is fading even thought I havent driven the car that much in past 3 years, and design is limiting my steering and it wasnt the exhaust guys fault when installing. And they dont make any extra sound, are pretty quiet.

 

[64 200 ranchero]

try taking the spark valve out of the carb and plug the hole. I did that to my old 1101 carb. That gap seems a little big, maybe lower it to 45 and advance the timing more. I ran 16 deg and removed the vac advance. See if any of that helps.

 

[CZLN6]

Howdy:

Sorry for your frustration. Something is not right. Have you checked your timing mark/notch on the damper to make sure it is indication top dead center? They have been known to move making for inaccurate initial advance settings. your description of the engines symptom sure sounds like timing issues.

Is your 1101 from the '69 250 or from the '63-'64 240? The former is plumbed for a ported vacuum source. The latter is for a Load-O-Matic type advance. You will need a carb with a ported vacuum source to marry with your DUI distributor.

Have you ever checked the vacuum modulator on the C4 trans? frequently the only symptom of a bad modulator is trans fluid disappearing with no sign of drips.

Did you get your better MPG with this carb?

Adios, David

 

[havoline]

well drove down to LA and every time I accelerate it sounds like it pings....at any RPM, then when you finally give it enough time with the gas to catch up it makes less noise and when at a cruising speed its ok and drives well. But I have no acceleration and now the car is even a more hurry to jump from 1st to second to 3rd gear at low speeds.

It sounds like I have a exhaust noise and I know that is so not the case cause it only happens under acceleration. barely able to get over the grapevine, had to wait until it slowed down to 45 mph before I can have enough to smash the pedal 100% to have it kickdown to 2nd and get back to 60mph or close to it.

Anyone know anyone thats going to be at the FABULOUS FORDS FOREVER SHOW in Anaheim this sunday?

And I adjusted the timing many times from initally 12 to 14 to 16 and 11 and down to 7-8 and made no difference.

Is it possible my DUI is not calibrated properly even though I told Performance Distributors that my car was mainly stock except for headers from CI?

I know my timing marks are right on otherwise for the past 15 years I would have had problems plus a few years ago installed new balancer so no slippage at all. And my 1101 is for a 200....am I to assume that I should have my DUI vacuum go into the carb instead of of my intake manifold??

 

[CZLN6]

Howdy Back:

Yes. The vacuum line from the distributor vacuum cannister should go to a ported vacuum source on the carb. It is higher up on the carb body. That would be the proper connection- unless the DUI folks set it up differently for you.

The 1101 was never used on a 200 engine. Only 1100s. The only 1100 set up for a ported vacuum source were the down sized 1967 & 68s. They were non SCV plumbed for use with the new (For those years) Non-LoM Distributors.

Have you thought about reverting back to your original OEM Load-O-Matic distributor with the Petronix for a comparison. IF that solves this mystery you can take a look at the DUI.

Hang in there.

Adios, David

 

[havoline]

well made it to and from LA, barely made it over the grapevine...didnt overheat.

have made more of an assessment of what is going on: pulling too much vacuum.

old distributor did ping but only at full throttle at higher speeds but only temporarily but went away if I retarded it abit.

THIS DUI distributor pings all the time under load. I will have to wait until tomorrow to talk to Performance Distributors about how they set up my distributor.
When I set up the inital timing and put it for 8 instead of 12 with vac line plugged/disconnected and then hooked up it then pulls almost to 18-20 degrees btdc at idle...

I am unfamiliar of how tense the springs are supposed to be or if it is possible to adjust the vacuum canister.

All I know is I dont want to go backwards revert back to stock distributor when all I want is to improve it.

I have hooked up the vacuum line back to the carb it made no difference and actually made it have a little more unsteady idle, so put it back to the port on intake.

I dont think my mileage improved as well despite putting premium in the car which I never do just to help reduce the pinging.

I will not try to yell at Performance Distributors tomorrow cause I just spent almost $500 on nothing but trouble.

 

[1986F150six]

The Duraspark distributor I bought from Performance Distributors is adjustable, regarding the vacuum canister. Turning the adjustment screw clockwise brings the vacuum in earlier. From what I understand, the total amount of vacuum advance is not altered, just the point at which it comes in.

 

[bubba22349]

havoline wrote: My overall goal has been to have best fuel economy and gain some power. Car feels like it is dragging something at lower speeds and it's really bad mpg in the city. I am lost in my decision making of what to do.

havoline wrote: Engine feels like I have to give it more rpm to move.

havoline wrote: I want my car to run good and for most part it has been doing that until screwed with making it work harder than it needs to. Would that mainly account for the bad fuel mileage?

havoline wrote: My overall goal has been to have best fuel economy and gain some power. Car feels like it is dragging something at lower speeds and it's really bad mpg in the city. I am lost in my decision making of what to do. Either I continue and hope a bigger carb will do the trick, update my autolite 1100 to a universal carb on classic inlines or rip out the headers and return to stock exhaust manifold.

From reading many of your posts over it looks to me like you have several problems going on! As "1986F150six" stated “Check your brakes for proper adjustment.” X2 It sure sounds like the brakes are not right, from your descriptions above like "it feels like something is dragging" and "I have to give it more RPM or power to get it to move", "poor mileage in city driving"', etc. Have you tried actually checking the brakes adjustments? I know you have said they are new and been bled, but that doesn't really mean everything is working as it should. I am assuming that you did a Disk brake conversion on your car. First thing did you use a compatible Disk / Drum Master Cylinder? If not the front brakes are likely dragging (drum bake master cylinder have the wrong residual valve) test this by jacking up the front wheel’s pump the brakes then let off and then see if you can turn each wheel freely. Even if you used the correct Master Cyl. another cause is that the push rod from brake pedal is not adjusted right (needs about a 1/8 to 3/16 inch gap before touching the master cylinder piston) so that it has the correct clearance and is not holding the piston down some. Test this the same as above. Also with the car on a flat surface and Trans in neutral can you push the car forward and backward easy? Is the emergency / parking brake been adjusted properly so rear drums don’t drag? Dragging brakes are a one of the biggest causes of poor performance and lower MPG. The good thing is that it may not cost anything or at least not very much to fix.

havoline wrote:Also the car is having a hard time now since the header upgrade changing from 3rd to 2nd gear unless I really smash the throttle. No line leak.

It also sounds like your Transmission needs some simple service work (its really easy) to adjust the Kick Down / Passing gear linkage so it will down shift at the right time.

havoline wrote: Again main purpose is to have alittle more power but mainly have a dependable driveability.

havoline wrote: Either I continue and hope a bigger carb will do the trick, update my autolite 1100 to a universal carb on classic inlines or rip out the headers and return to stock exhaust manifold

You can change back to a stock exhaust if you want but its not going to fix your problem! A free flowing exhaust system with or with out a header can only help improve your gas mileage by about ½ to 1 or more MPG and with also have an increase in power, providing the engine is tuned properly to take advantage of it! This would go along with your main purpose of having a little more power and dependable drive ability. Lastly you also need to find the another carb (1968 up) an Autolite 1101 or other that has the correct vacuum hookup for the later style distributor you are using. Its not very easy (it takes some very advanced tuning skills) to get the tune right with it hooked up to the intake manifold for a vacuum source its just not a good practice for a daily driver type street car geared towards better economy, it pulls in too much vacuum advance too fast.

havoline wrote: Also how do I edit my signature at the bottom it's out of date now?

There is a tool bar button located at the top of the Forum page (left hand side) its the “User Control Panel” click on it and you can edit all your info. I know that it can get frustrating some times getting stuck doing changes without improvement but hang in there. Most of the things that could be some of causes of your problems should be a "no cost" or "low cost" items to fix. Good Luck.

 

[bubba22349]

So did you make any progress on fixing your Mustang's problems?