Operation NP435 & Over Drive

Wife wanted to go out for dinner so I made her work for it
While I drove and yelled out numbers she wrote them down, here goes.

Speed    Direct      OD
40         1300       1100
45         1500       1200
50         1700       1300
55         1800       1400
60         2100       1600
65         2250       1700
70         2500       1800
75         2700       2000
80         3000       2200

I don't know why the 1800 in direct or the same RPM for 50 & 55 MPH?
I have 1 tanks full running at 65 MPH like I did with out overdrive but now have AC that has been running non-stop. Anyway I only pulled 14.8 MPG, I was getting high 14's to mid 15's before the overdrive.
Dave ----
edit: to make change to the RPM's that were not right 8-24-202

Great info Dave. Bet it sounds like a completely different truck inside cruising at 65 with the OD on.

Yes it does just wished the MPG were up a little bit.
After the next full tanks I plan on doing the speed limit of 70 MPH for a few tanks to see where that gets me.
Dave ----

Something seems awry.  Doing some simple math, dividing the Direct # by the OD #, gives the following ratios.  I think the 1.31 - 1.39 ratios are probably within the limit of your tach and ability to read it.  But the readings from 40 to 55 are very suspect - unless you shifted gears.

Speed    Direct      OD       Ratio
40         1800?      1100    1.64
45         1500       1250     1.2
50         1700       1700?   1.0
55         1900       1900?   1.0
60         2100       1600     1.31
65         2250       1700     1.32
70         2500       1800     1.39    
75         2700       2000     1.35
80         3000       2200     1.36

When the wife told me they were the same I like
For the 50 to 80 MPH in direct was first when I got on the high way.
Then went into OD and did the 80 to 65 or 60 and did the rest of the drive on the high way at 65, speed limit is 70 MPH there.

On the way home I took "local" roads with the speed limit of 45 to 55 MPH so I did the 40 to think 55 in direct then shifter to OD to do the rest of the numbers.

I will have to recheck them numbers as something just did not add up.
I should have rechecked them when we were out but we were just enjoying the ride.
I also was showing her were I have made some LP drops and on roads I had not been on before.
Figured I would post what I found so others would know "ruffly" what I was getting in what gear.
Dave ----

Dave, I think your wife is just screwing with you!   

Gary would understand 'taking the piss' in his Brit lexicon.

ETA: having a laugh, at your expense.

"Having you on" is what I would have expected a Brit to say.

I guess I know a much lower class of Brits than you do.

Nothing unexpected..

Yep I think she got my goat
Dave ----

Yeah Jim, Gary must have interacted with lords and ladies...
'Taking the mickey' is the less crass version, but what you said is definitely what I heard and said the most...

And it sounds like the OD is working out great Dave, enjoy it!

Well Rob, Gary seems to have both a good lord and a good lady at his side, so there's nothing wrong with that!  

ArdWrknTrk wrote

Well Rob, Gary seems to have both a good lord and a good lady at his side, so there's nothing wrong with that!  

Amen, brother!  

You ARE blessed, Gary!  

Agreed!

You guys are right - I am BLESSED!  

I edited my post to speed / RPM of what I got on the ride home from work today.

I did 40 - 55 MPH direct and 45 - 55 OD, I did not check the other speeds / RPM's as they seam to be ok.
The first tanks fulls did not get the MPG higher (@65 MPH) but I will run 2 more tanks fulls just to make sure.
Then I will run 2 tanks fulls @70 MPH to see what that gives me, nay be lugging the motor at 65 MPH?
I also feel the carb is really out of wack as it was really messed up when I rebuilt it and I think the rod / seat (main jet set up) has been jacked with and it running way to rich to only be getting high 14's to mid 15's
Dave ----

Jonathan just put a Chinese clone YF on his truck.

Maybe watch to see what he encounters???

ArdWrknTrk wrote

Jonathan just put a Chinese clone YF on his truck.

Maybe watch to see what he encounters???

Hope he posts what he finds if anything with that carb.
Mine runs great other than the bad MPG and I really think someone messed with the Rod & Seat adjustment because everything else was messed with, sheet metal screws use in some holes and no screws in others, choke hot air was missing a fitting, just an over all MESS!

When I rebuilt the carb the paper did not list an adjustment for the R&S so I did not touch it, who would right?

I want to run 2 more full tanks at 70 MPH and see what that gets me, last 2 were at 65 MPH as that is what I was doing with out the over drive.
Then I will check the timing & and look deeper into the R&S adjustment.
Dave ----

FuzzFace2 wrote

I want to run 2 more full tanks at 70 MPH and see what that gets me, last 2 were at 65 MPH as that is what I was doing with out the over drive.
Then I will check the timing & and look deeper into the R&S adjustment.
Dave ----

When I saw the speeds you are driving, I remembered posting a review of trips to Skiatook, OK over the years and thought I would share:

2014 55-62 mph with no aerodynamic modifications = 21.93 mpg [highest tank = 23.26 mpg]

2015 55-62 mph with aerodynamic modifications = 24.13 mpg [highest tank = 25.72 mpg]

2016 55-70 mph [weighted towards 65-70] with aerodynamic modifications = 22.05 mpg [highest tank = 23.46 mpg]

2017 Missing data due to having driven another vehicle.

2018 65-75 mph [closer to 75] with no aerodynamic modifications] = 19.87 mpg [highest tank = 21.3 mpg]

2019 65-75 mph with aerodynamic modifications = 21.65 mpg [highest tank = 21.95 mpg]

2019 60-75 mph with partial [see explanation, above] aerodynamic modifications = 19.12 mpg [highest tank = 21.17 mpg]
 

1986F150Six wrote

FuzzFace2 wrote

I want to run 2 more full tanks at 70 MPH and see what that gets me, last 2 were at 65 MPH as that is what I was doing with out the over drive.
Then I will check the timing & and look deeper into the R&S adjustment.
Dave ----

When I saw the speeds you are driving, I remembered posting a review of trips to Skiatook, OK over the years and thought I would share:

2014 55-62 mph with no aerodynamic modifications = 21.93 mpg [highest tank = 23.26 mpg]

2015 55-62 mph with aerodynamic modifications = 24.13 mpg [highest tank = 25.72 mpg]

2016 55-70 mph [weighted towards 65-70] with aerodynamic modifications = 22.05 mpg [highest tank = 23.46 mpg]

2017 Missing data due to having driven another vehicle.

2018 65-75 mph [closer to 75] with no aerodynamic modifications] = 19.87 mpg [highest tank = 21.3 mpg]

2019 65-75 mph with aerodynamic modifications = 21.65 mpg [highest tank = 21.95 mpg]

2019 60-75 mph with partial [see explanation, above] aerodynamic modifications = 19.12 mpg [highest tank = 21.17 mpg]

I would love to get your lowest of 19 or even mid 17's I could live with.
When I am ready to really get into this MPG thing I need to find your post of what was done for timing, carb and aero to get the numbers you did.

With the over drive I have been shifting at or just below 2000 RPM and even on the high way in over drive @ 70 MPH it is just at 2000 RPM IIRC, but I have been running 65 MPH because that was what I was running with out the over drive to get a good reading of apples to apples.

My gut tells me my main jet (rod & seat) have been played with before I got the truck. The carb was missing screws, had wrong type (sheet metal) screws and had parts in the wrong place.
I did not adjust the rod & seat as the paper did not give specs on it so I left it.

I don't have the money for a wide band AFR gauge so going to have to wing it but I am guessing if the rod goes deeper into the seat it would be leaner?
Some day I will jump into it LOL

Thanks for the information
Dave ----