You need one of these...

 

Dennis, since I'm not great on trannies, what is it?

Checked the vacuum gauge yesterday and at 55 it is 17.

 

Mike, that is a Gear Vendors O/D. I keep thinking I might install it, someday, on the C-4 in my '55 Ranchwagon. Bolts to the back of your transmission, the adapter takes place of your tail shaft. I'm running 3.55's in my 8".

I don't believe they make an adapter for your trans tho. Your still running the '46 trans??

 

Yes still the '46. If I end up having to pull the engine again, the old trans may go bye bye.

 

Ford made an OD tranny in that era I belive. It was for the cars though. Mostly mercs.

A .75 OD ratio would give him a final of 2.25. Probobly ok in a big block but mighty high set for a Y.

 

I am feeling better about my F-600 with the OD (locking TC) trans I have. I should turn about 2100 at 60........

On the "flat", empty, I should be 15 MPG or better running around 60...........


I have my fingers crossed!!!

 

I have been experenting with my 272 in my 57 pickup for better mpg for a few years now. And I can not get past the 19 eather. But I have gotten 18.99 witch I think that is great. Some of the things I have done was, I bought a air/fuel ratio guage it uses a o2 sensor in the exhaust pipe. I have a 500cfm elderbrock carb, using metering rod kit I have it leaned out as far as the carb will go. I gotta use the choke until it is warmed up. I have the timming set as far advanced as it will without it knocking. And 10w30 motor oil.

 

I've been wanting an O2 sensor for some time. What do you have, where did you get it? Also since I have duals would like to run it on one side only. Where in the exhaust system do you have it installed?

 

I found the guage at parts swap meet. You can get them any where like summet racing. It didn't come the sensor so I had from a 85 monticarlo. I welded a o2 sensor reapair fitting into the pipe rite after the hedders. It should be as close to the engine as possable it only works when it is hot. Mine is to far away and at idle it stops working because it cools off. I also have duals and only have it in one side I adjust both sides the same. I noticed rite away that it was running to rich at crusing speed it should be lean when the vacuum is high. It is ok if it is a little rich under a load or hard pull. If it is to lean under a hard pull you may get a spark knock witch can do bad things to your engine and loose fuel milage any way. Hope this helps

 

I use a Holley rich/lean indicator. It uses a 3 wire 02 sensor which has it's own heating element. It has 3 leds, one for lean, stoich, and rich.
If you really want to get fancy, you'll need a wide band because it will tell you how rich or lean you are. I'll be installing one soon in preparation for fuel injection and turbo. The wide band I have is from Innovate Motorsports.

 

I should stop talking about this and get one on .

 

Always have wanted a wideband for carb tuning.

I think the prime thing with getting milage on the highway is optimal cam timing and keeping vaccum high.

19 with a direct drive pickup using 50s tech is quite good in honesty. 21 mpg would be amazing. Now do you still have a pickup or do you have a high geared toy?

My current beater gets 18mpg using a T18, 300, and a 3.55 rear at 55mph. Is that increadible? No probobly not. But I can still haul a ton and pull around 7k at 55 and do it at 13mpg.

Running slightly lean at cruise on either a holly or edelbrock should pose no real issue. The purpose behind a powervalve or vaccum dampened metering rods is to allow for enrichment upon vaccum lowering. This means if your carb is set right chugging up a hill should cause no ping or serrious loss of power. Getting your vaccum up and insuring that you have propper atomization.

For instance a carb sized at 500cfm on a 272 would require you to turn near 8000rpm to
us all the airflow in it assumig that you have an 85%VE which is very generous and more in line with a mild N/A race engine. Try a 390 or so. Bet you will eke out another mpg and have much better throttle response.

Remeber these are pickups. Not cars. You have the wind area of about three fridges stacked up folks.

 

If I bought another guage I would get the one with a heated o2 sensor. I think the one I have is a wide band but I am not sure, I would get that for sure. Is my truck a high geared toy? Was that for me? No not really it has a 3.50 rear with the tallest tires that will look rite. T98 trans with 50w oil in it. stock 272 I do have the msd distributor that gives you the freedom to adjust the timming curve. And the aluminium intake, yes the carb is to big but runs ok. Some things I have learned after I had allready bought them. One day I would like to get a smaller carb. Maybe I can get a little better mpg. But I agree that we are pushing air and we are only going to get it so good, modern pickups don't do much better.

 

An o2 sensor from an 85 monticarlo is not wide band. It should be the most basic 1 wire sensor, the same as is on my '88 Firebird. A wide band has 4 or 5 wires. Any less and it is not a wide band. And not all 4 wire sensors are wide band.

You don't need another gauge to go from a 1 wire sensor to a 3 wire sensor. On a 3 wire sensor, 2 of the wires are for the heating element. Make sure the heating element circuit is hot with the ignition on and run the other wire to the gauge.

 

"19 with a direct drive pickup using 50s tech is quite good in honesty. 21 mpg would be amazing. Now do you still have a pickup or do you have a high geared toy?"

No question! High geared toy.