air fuel ratio's

Has anyone made any progress with A/F ratio meters on a blown alcohol motor lately? What is the correct A/F ratio anyway? There are now systems out there now that monitor all 8 cylinders, is anyone using one yet? I know that reading the plugs gives you a good idea of whats up but it's only telling you what is happening right before the finish line.

 

I agree with you Jodie, it would also be nice to know for sure if a high EGT is a lean condition or just fuel burning in the pipe.

We are going to try an LM-2 on a car and see if we can get 1 AFR readin as a backup for a given hole. If it works we may elaborate but we haven't actually tried it yet. I thnk Racepak is making a 8 sensor unit but it isn't cheap. If you could taylor your fuel delivery throughout the run, it would have to make you quicker. Great feedback for a fuel management system.

WJ uses them.... why can't we?

 

I'm in! I've posted a couple times trying to find people using them. I know innovate makes one that will monitor all 8 cylinders. It's close to 2k for the setup, but i believe your "fine" tuning skills would come by a lot easier. I guess you could invest in a one sensor setup and starting monitoring cylinders that are getting hot. Would be a good way of getting your feet wet w/out a ton of money invested.

 

my lm1 will read tp .65 Lamdba

 

Racepak has the control box for o2 sensors 50% off through the end of November. A set-up for all 8 is around 2,800.00 I think. Saw it on their forums. That was for a V-Net system.

 

Yeah Mike that is a problem...on the innovate system i believe they can freeze up when the afr's get below 3.5, then the box needs to be reset i believe.

I tried to look for the V-Net system on Racepak's website...is this a system specifically for running O2's??? I don't run Racepak so was curious if you could buy just an O2 system from them.

Josh

 

The vNet O2 system is meant to be hooked to the vNet digital bus like is used on the V300 we run. Most of their newer units use the addressable vNet bus for the majority of their transducers.

In other words, I think you would have to have one of their vNet style recorders before you could use it.

Have you tried the Innovate and had it lock up? We have the unit wired but have yet to make a pass with it. We can use the system on a bracket car so it isn't a loss if it doesn't work on the blower car.

 

Innovate claims that their systems work with alcohol but perhaps they are referring to a carbureted animal.... not with the AFR's we run. I can't really say if it will work until we try it. We already have the system so it isn't costing us anything.

 

Back when we were running a blown sbf on alky, we had it on an engine dyno w/ the innovate system hooked up. The system would only read as low as 3.5:1 AFR. So at idle they were stuck there, then when we starting revving the motor up usually there was a couple sensors that didn't clean up and were stuck at 3.5 until the system was cycled off then back on. So I wasn't sold on it knowing that there could be some cylinders not reading going down the track due to idling before launch.

Josh

 

Some O2 sensors have a heating element built in to assist in maintaining a constant standard, this may improve the accuracy when running low A/F ratios?

Might be something to ask vendors of different systems.


Jeff
NorCal

 

Racepak does not recommend their A/F sensor system for blown alcohol.

 

race pak new set-up

we just purchased a set-up for are promod to use with collecters, one in each collecter. when i spoke to them (Todd) he told me that it will read the full alcohol range 2,5 to 6.5 and can be programed to read gas or alcohol. we will use it to see where we are as far as overall tune. egts to balance and give us the tune-up and then we can see if we can lean out a bit more. we can also use on our gas car!!!