Turbo BS Thread

Could you get lucky by just putting a larger intake diameter around the mad on it and trick the truck into sucking more air in than it thinks it is... Seems like math would be involved

 

Compression ratio won't affect air/fuel ratio. You might try cleaning your Maf to start. Other issues could be leaking/stuck injector, bad water temp sensor (happened on my Sr years ago), wrong heat range or improperly gapped/worn spark plugs, weak coil. Just some thoughts, good luck.

 

This. Clean it all up and see how it acts. Could be a possible vacuum leak, too.

Or this. Several sizes available on fleaBay.

 

Unfortunately I've already done most of the easy stuff. I have a vacuum gauge on it and it pulls good vacuum, I've tested and cleaned the injectors, I've tested spark wires , replaced ignitors, replaced spark plugs, I have 3 mafs I've rotated to see if there was any difference, replaced and tested o2 sensors and a bunch of other things as well. With the obd2 scanner I can see all the sensors and they're values as they should be.

I still don't understand how compression doesn't affect afr. If the computer is from a year with a higher compression shouldn't the base fuel map have too much fuel for a lower compression piston? I get it's supposed to adjust but there's a limit to how much injection the ecu could pull right?

 

The whole closed loop section running fat? Somewhere in there your volumetric efficiency changed. Sounds like you need to tune that ecu. Still running oem headers, cats and intake?

 

@5 Lug Fury
I might have to retract my 1st sentence. I spoke with my neighbor who has tuned many more engines than I have about this and he says more compression ratio will likely require more fuel. This also coincides with what @MadTaco461 said, since lower compression would lower the VE of the engine, thus requiring less fuel.

 

I just spoke with someone who pretty much only does 1uzs and he said it should run better as the fueling is better with the gen 2 computers. He said there's either a wrong part or something in the wiring. Since I've pretty much already touched all the sensors and there's only a select few "wrong parts" I guess I'm going to be ripping the loom back apart.

 

So it is rich both closed and open loop? Same observable richness?

 

It's hard to say because it jumps to closed pretty quick but I do feel like it runs better in open. I'm assuming it's something with the grounding or something with the o2s or maf. All the plugs are black so it's on all cylinders.

 

Assuming you have a stand alone AFR sensor, can you unplug the o2 sensor to force it into open loop and then monitor AFR. If that’s kosher then it’s definitely a bug somewhere. Are the MAF and o2 for/compatible with this engine and ECU? A few millivolts off on the MAF or o2 would skew fueling some. Is the fuel regulator OEM pressure and does it have a vacuum line ran to it?

 

Would someone be interested in a radiator? COVID hot hard and I have to sell some parts to get by. Ron Davis racing radiator with dual 16” spal fans with shroud. This is the same on that was built for @Torspd.

 

I wonder if I could make that work for my 2.7... @Torspd any thoughts?

 

2.7 and 4.0 are the same radiator.

 

Really? That's surprising. Nothing has ever swapped over from a v6/6lug to my 4 bangin 5lug.

 

They're the same on 6 lug. Don't know why they'd change it for the 5 lug.

 

It's more the v6 -> i4 that I'm surprised at. I figured the v6 radiator would've been thicker, different inlet/outlet, different mounting points, any of that.

 

This is accurate. We did a variety of referencing while figuring out the list of workable vehicles.

 

Thought you guys might find this interesting, my stock rods on (too much) boost.

 

Variable compression ratio.

 

how many psi were you running?