Redneck DoD

[L31MaxExpress]

Anyways, my point being that if worked in the trucks as well as the vettes I think people would appreciate it more. That and if it didn't have a tendency for the lifters to fail.

Smaller engines in trucks have never worked out for economy. In a fullsize truck something like a 4.3L gets relatively similar mileage to a 350 or even 454. In some cases I have seen the larger engines do better on fuel because they are not into power enrichment all the time just to make it up the next hill. This is especially true on carbureted engines where low vacuum opens the power valve or the power piston moves the metering rods to full send.

 

[Supercharged111]

If you "ground out" the injectors, does the excessive current flow then pop the drivers in the computer?

I'm thinking that if you HAVE to do this, you want to OPEN the circuit, not ground it.


Drive slower...


...and/or fix the engine so it runs properly. Assure all "tune-up" items are in good condition. Inflate your tires to proper pressure. Make sure the brakes don't drag. Put synthetic lube in the oil pan, differentials, etc. for reduced parasitic losses.


Yes.


Blowing "atmosphere" (air) into the exhaust will screw-up the O2 sensor readings, leading to a false-lean condition. The computer compensates by going into "rich command" where it's adding more fuel to the cylinders that do run.

This is a REALLY BAD idea. You wash the oil off the cylinder walls with a too-rich mixture, and bore wear, ring wear, and maybe piston scuffing increases.

The computer doesn't supply injector power, rather it grounds the injectors. So manually grounding them will leave them fully open all the time. Would make that #3 misfire less of a priority.

 

[L31MaxExpress]

The computer doesn't supply injector power, rather it grounds the injectors. So manually grounding them will leave them fully open all the time. Would make that #3 misfire less of a priority.

Hello hydraulic lock and bent/broken rods.

 

[0xDEADBEEF]

Smaller engines in trucks have never worked out for economy. In a fullsize truck something like a 4.3L gets relatively similar mileage to a 350 or even 454. In some cases I have seen the larger engines do better on fuel because they are not into power enrichment all the time just to make it up the next hill. This is especially true on carbureted engines where low vacuum opens the power valve or the power piston moves the metering rods to full send.

In our Yukon it saves a fair amount under 55 mph, or it claims to. Any load and it kicks back into V8, so unless you are going downhill or have a tailwind 99.9% of the time it doesn't do anything above 55. It's huge compared to the GMT400 though. It'd be interesting to see someone swap a GenV with AFM enabled into one of these trucks. I could see it working well in a RCSB, or at least better than my Yukon.

 

[L31MaxExpress]

In our Yukon it saves a fair amount under 55 mph, or it claims to. Any load and it kicks back into V8, so unless you are going downhill or have a tailwind 99.9% of the time it doesn't do anything above 55. It's huge compared to the GMT400 though. It'd be interesting to see someone swap a GenV with AFM enabled into one of these trucks. I could see it working well in a RCSB, or at least better than my Yukon.

My buddy has a square body S10 with a L83 and 6L80E in it. He saw ZERO difference in fuel mileage with it disabled. I did completely tune out the PWM slip though. I fell like what it gains cutting cylinders it loses to torque converter slippage.

 

[Pinger]

If you "ground out" the injectors, does the excessive current flow then pop the drivers in the computer?

I'm thinking that if you HAVE to do this, you want to OPEN the circuit, not ground it.

The above point is dealt with in a later post, just to add - that when disabling injector(s), the ECU still has to 'see' them. Emulators as used in LPG/propane conversions do this.

Blowing "atmosphere" (air) into the exhaust will screw-up the O2 sensor readings, leading to a false-lean condition. The computer compensates by going into "rich command" where it's adding more fuel to the cylinders that do run.

This is a REALLY BAD idea. You wash the oil off the cylinder walls with a too-rich mixture, and bore wear, ring wear, and maybe piston scuffing increases.

And, negates the aim of improved fuel economy. Expect fuel laden oil also.

 

[0xDEADBEEF]

My buddy has a square body S10 with a L83 and 6L80E in it. He saw ZERO difference in fuel mileage with it disabled. I did completely tune out the PWM slip though. I fell like what it gains cutting cylinders it loses to torque converter slippage.

Did he have a way to view/log instant MPG?

 

[L31MaxExpress]

Did he have a way to view/log instant MPG?

Yes and after driving it for 2 months tracking mileage with his Fuelly app in normal driving had an exact MPG.

 

[mpyusko]

If you "ground out" the injectors, does the excessive current flow then pop the drivers in the computer?

I'm thinking that if you HAVE to do this, you want to OPEN the circuit, not ground it.


Drive slower...


...and/or fix the engine so it runs properly. Assure all "tune-up" items are in good condition. Inflate your tires to proper pressure. Make sure the brakes don't drag. Put synthetic lube in the oil pan, differentials, etc. for reduced parasitic losses.


Yes.


Blowing "atmosphere" (air) into the exhaust will screw-up the O2 sensor readings, leading to a false-lean condition. The computer compensates by going into "rich command" where it's adding more fuel to the cylinders that do run.

This is a REALLY BAD idea. You wash the oil off the cylinder walls with a too-rich mixture, and bore wear, ring wear, and maybe piston scuffing increases.

Thank you for your constructive response. It seems a few have gone off on an unrelated tangent.

You assume all my O2 sensors are working (both downstream are not)

Driving slower isn't always an option. I am not a speeder. I generally stay within a few MPH of the speed limit or as traffic dictates. Locally the limit is 55 or 65. But going cross country, the limits are higher.

I will say (to all the MPG tangent discussion folks) I left Atlanta once a few years ago and had the cruise set to 83MPH for 6 hours straight. Regardless, there is a very short list of vehicles that can muster 550 miles of endurance out of a tank at that speed. I was pulling 13.5 average.

Since then, I've replaced the fuel lines and filter, and done a few tune-ups. I'm getting 12.5 average mixed driving right now. (Used to be 10.5 to 11.5). So I'm optimistic about my range on the road trip.

Someone stated earlier mentioned "flow-matched injectors". How about a recommendation? I want to replace all 8 before I set out, but I'm nervous about getting crap. 6 to 7 thousand miles for a road-trip, I want to make sure everything is running top-notch before I leave.

(Wish I could get my A/C working before then.)

 

[mpyusko]

Hello hydraulic lock and bent/broken rods.

Atomize it to compress it into a liquid again. Hello cherry-red cats. Lol