NM-XJ

Pretty sure Dave51 meant heat soak of the entire engine bay, from which the air charge is drawn into the air box. But don't dismiss the amount of energy you can dump into air with the right temperature differential and contact surface area. Q = m*Cp*dT.

I like the fact that Dave is already putting numbers to this. If we're going to enginerd this, might I suggest a hole within 1" of the existing IAT? Pop in one of these bad boys (check calibration by dipping in a glass of ice water then a pot of boiling water) and see what you get compared to the IAT. Since it's not going through the ECU, it will work as a "truth source" for actual unmolested fluid temperature in the manifold. I looked for a similar probe-style TC on Summit Racing but didn't find anything equivalent or cheaper. I suppose you could also just drill a smaller hole and insert a simple welded wire cold junction K-type TC and goop up the opening around with with high temp RTV...but that's ratty and janky.

Dave51

Right next to the IAT, large enough to accommodate a thermal probe that would remain unaffected by the heat of the intake manifold as described by NM-XJ. We'll also need a hole to check the temperature at the spot where the IAT relocaters are putting the IAT.

Dave51

I believe this is the mantra of heat soak conspiracy theorists. It is the heat of the intake manifold that largely heats up the IAT and not the airflow.

denninski

Ten mpg is miserable, it must be a tank.
I have a Ford pickup like that so I just put it in storage 15 years ago.

1. advance ignition timing
2. increase compression ratio
3. change to very mild camshaft
4 . put a vacuum gauge in so you can stay off the throttle, it takes effort.
5. change the rear end ratio to 3.07
6. reduce rolling resistance by
a. reducing vehicle weight, takes discipline but can be done
1 change all glass windows to lexan
2 remove tire chains and spare tire
3 remove extra seats and people
4 remove hood and other heavy metal parts
5 remove heater, radio, aircon , bumpers, doors etc.
6 change to very light modern battery
7 change automatic transmission to manual one
b. change to thinner tread tires (old worn out bias ply tires have less rolling resistance than radials)
c. pump the tires up hard, really hard now they might pop and you will need the spare that you don't have
d. use narrow tires. In mpg competition some cut off all of the tread but an inch right in the center

7. Reduce air resistance
drive slower, 40 mph
cover the missing doors with plastic

8. throttle use. A friend used to tap his foot to music when driving. I rode with him once and was very annoyed with the way his car lurched along to the music.
He could not get good mpg. We explained it to him but he would rather listen to music. It is all about priorities.

9. You can do all of the above, but if the engine is not right it will not help. You might change the engine or car for a more economical one.

denninski

The above may seem extreme but I did most of them (but not the cut down worn out tires) beginning with a cut down postal delivery jeep (DJ5). It had a non-jeep engine that got 3.5 mpg. With careful tuning it improved to 7 so I changed to another type engine and immediately got 15 to 23 and had 4 times more power