You say you didn't loose any torque under 1200RPM? I'm really interested in that; I've got a T18 and 3.00 gears, and 800-1200RPM torque is really important to me. I'm going to end up with EFI manifolds and an Offy intake.

 

It doesn't seem to. I tried some second gear starts without the trailer and it seemed just about the same from 800-1200RPM and much better above that.

Vince

 

Fuel mileage results:

On two runs to the Bay Area (100 each way and 125 each) I got 12.6 MPG while towing at 64 MPH.
I kind of killed the science because I am driving a bit faster.. I used to get around 12.2 MPG traveling at 62 MPH on a much flatter and less cluttered hwy.
So not exactly a perfect test, but I am getting better mileage and driving faster at the same time. All good things.
As I mentioned before the truck is far easier to drive and maintains cruising speed with out having to watch for little hills.
At 64 MPH (GPS) my engine is turning 2300 RPMs.

Vince

 

Compaddict- what gears and tires are you running? You tow in 5th or 4th?

 

I don't know what gears.. Stock sized tires though. And I tow in fifth gear.

Vince

 

Stock tires- 215/75R15 or 235/75R15? At 64mph, in 5th gear with an M5OD, 2300RPM suggets you've got 3.73 gears with the 215 tires. My tire calculation could be off, though. It assumes perfect geometry, and is probably incorrect. So it's probably 235 tires. The 215 tires look tiny on these trucks.

There's usually an axle code stamped on the VIN plate on the door sill. K is 3.55; I'd have to look up the others. Your 4x4 is probably 3.73.

 

I would guess 3.55. The tag on the axle will have the ratio stamped in it. IIRC, it's on the top left corner and will probably say 3 08, 3 55 or 3 73. If it's a factory limited slip there will be an L between the number instead of a space. My truck pulls 2000 rpm at 60 and 2500 at 75 with 3.08 gears and tires the OD of the 235's.

 

Okay, I just set my base timing at fourteen degrees BTDC.
Experimenting in fourth gear without the trailer I can make it ping in extreme cases. I would never bog my truck down like that in the real world, but with the trailer on the highway it's still a possibility. I'll keep an ear out this Sunday.

The last three tanks I got 12.6 MPG each with the new camshaft.

I'm racing this weekend in the same area the last three tanks were driven. So we will see.

Vince

 

One more thing, I just passed CA smog testing with flying colors as well.

Vince

 

Okay after setting timing at 14 degrees BTDC running 87 octane CA gas the truck pings bad pulling most any kind of grade while towing. I had to keep it out of cruise just so I could shift so it wouldn't lug.
The truck got 13.2 MPG on that tank of gas which is 1 MPG better than the last three tanks.
I filled up the tank with mid-grade 89 octane and it pinged alot less. Running on 87 grade the computer could not back the timing off enough to stop the pinging. On 89 grade the engine would start to ping, then back off the timing and the pinging would stop.
I headed up my test hill that before the camshaft I could only manage at 55 MPH and after the cam it made 60 MPH. The truck and trailer took the same hill at 65 MPH!
So, I'm going to back the timing off to 12 degrees BTDC and test again next weekend.
Any pinging is very bad for engines and 14 degrees (at least with the Crane cam) is to much advance.
I'll have to test with 89 octane because that's whats in the truck now. I figure even if I have to run mid grade fuel, if my fuel mileage goes up and I get that much more performance out of my setup.. My truck is just about perfect for what I use it for.

Vince

 

Have you reset the computer yet? It may solve your pinging. After a disconnect, the EECIV computer goes into learning mode for about 10 miles of sedate, steady-speed driving and learns what the normal operating-range sensor values are, and uses those values from then on. You'll probably see a difference after you re-learn your computer. You might even have some stored codes that aren't turning on the CEL, but are important, like a lean condition. There's threads on how to read the computer codes with a paper clip.

If it's simply pinging at 14.7 stochiometric and everything else is fine, you may be stuck with retarded timing and/or higher grade fuel. However, the EFI 300 motors have tiny, tiny little injectors (12LBS, I think) and not much fuel flow potential, and often run lean under load (especially if the injectors are old). The old motor design likes to run a little rich anyway, and 14.7:1 is on the ragged edge of detonation for them.

A cheap way to increase fuel flow a little to compensate for your increased airflow is to adapt a 302 V8 adjustable fuel pressure regulator to your engine. They're cheap, plentiful and require only the fabrication of a mounting ring to mate to a 300. There's plenty of threads about it on FTE. You may find another few PSI is all you need to keep from going lean under high loads.

Or, you could combine an adjustable pressure regulator with higher-flow 19lbs injectors, which are stock on alot of other Ford motors (I think). You'd probably have to turn the pressure down a touch in that case, because of the higher flow, which might not be a good thing. The close proximity of the injectors to the exhaust manifolds neccesitates an unusually high fuel pressure (45+ psi) to keep the fuel from vaporizing in the injector bodies.

The EECIV computers don't respond well to airflow increases (hence the pressure regulator/injector workarounds). They base the airflow calculations on throttle position, manifold pressure and maybe RPM, then get baseline fueling form a lookup table and trim it with O2 sensor feedback. There are aftermarket computer chip options that will be able to help you out. Superchips model 1100 chip is a generic Ford EFI chip where you specify your 4-digit computer code and whatever mods you've done to Superchips, and they do a specialty program for you. Cost is $200-300 and may give you another big power boost on top of the cam due to better spark timing and fuel management. Hypertech makes one too, but the Superchips 1100 is probably best, because it can be tailored to your needs.

Ford saddled these engines with crummy induction systems time and time again. If you look at the bore, rod and stroke geometry, each cylinder breathes exactly like an underbored GM 454, which is a big agressive motor. You've got it breathing big, now make sure it gets fueled big.

Or your timing could just be too far advanced. :-)

 

Adjustable regulators top out at 60psi, which is stock pressure for the 300. I was able to get a little more out of mine by trimming the vacuum tube down so the screw would go in further and a littler more still by chucking the screw in a lathe and cutting down the underside of the adjusting screw.

 

Oh wow. 60psi stock?

 

Egads, far to much work you guys!

I could try reseting the computer again, but my testing run is like 100 miles and I really don't like to let my engine ping if it doesn't help.

Let me set the timing back two degrees and see how much added performance I retain.

If the two degrees doesn't help, I might send the injectors in to get cleaned and blueprinted.

Thanks!

Vince

 

Oh, if you've already reset the computer, then there's no need to redo that. Might check it for codes, though.