Wild new computer controlled AFR system for carburetors.

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Installed mine and have to take it back out. No power to the IAC for some reason. They suspect a bad board. In hindsight, I should have connected everything on a bench and tested it before installing it on the car. Oh well. They don't call it Beta Testing for nothing.
 
I got mine installed this morning. It was pretty painless. I just did the main 4 wires to install. There's still 2 leftover for the relay if I come up with anything I want to hook up to it. And the while wire for the 2-step rev limiter.

The system does have a couple little quirks to it. I guess the MAP sensor recalibrates when you turn the car on and off. I did have a couple times during the install when the thing came on and it was reading wrong for the MAP. I think the extension cable I got for the MAP is buggered and contributing to the wonkiness. When I plugged the MAP directly into the main harness without the extension cable, it behaved more like what I expected it to.

Next up, with the car idling, and the auto-tune feature disabled, I could feel it sucking air through its air bleed. I emailed them and they said basically it wont seal up perfectly when its new. The IAC seats up against a seat in the anodized aluminum body. After you use it a while, the IAC is supposed to wear into aluminum and eventually create a better seal.

And then the assumption we had, if the thing ever fails, your car reverts to just a normal carbeurated car. That's not entirely true. When the carb cheater "parks" the IAC, it pulls it away from the seat to prevent them corroding. So its normal resting position is introducing a vacuum leak. To prevent the vacuum leak, you can pull the hoses loose and reconfigure them. Where the MAP and IAC connect to the carb spacer, run one of the hoses and connect both of those ports in their spacer.

As it relates to our 71-73 mustangs, there is enough room on the shock tower braces for both parts of the system. Initially, I was going to put the main box up by the front headlight bucket. With it there, I didn't have enough wire to plug in the O2 sensor. We would need a longer wire for that. So for now, I have it mounted to the shock tower brace. I put the main box on top just in case i need to remove it. After its been there a while and I'm sure it works good, I plan to mount it to the bottom of the shock tower brace where you wont be able to see it.

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So can any of you guys that have installed this device give a review of its performance?

Does your car run better?

I am assuming that since the device is introducing additional air through a controlled vacuum leak you need to install larger jets to give it something to work with?
 
So can any of you guys that have installed this device give a review of its performance?

Does your car run better?

I am assuming that since the device is introducing additional air through a controlled vacuum leak you need to install larger jets to give it something to work with?
Overall, it works. It has a positive effect. Even with the wild temperature swing from summer to fall and even some mornings now with ice on all the windows, the car cranks right up and AFR is mostly in the range where it should be. Realistically, I should swap some jets or something in my carb to get it closer to dialed in for the colder winter air. I haven't had to. The carb cheater just does a little more compensating.

The way it works is not nearly as fast as an EFI system with fuel injectors. The little IAC it uses takes a second or two to go from fully open to fully closed. That means it can't perfectly compensate for if you have your carb set correctly for some situations but incorrectly for other situations, IE dialed in for idle but not so great for cruise or WOT. Imagine your carb is not adjusted right for power mode, but it is adjusted right for idle mode. As your sitting there at the red light, the IAC is closed and your AFR is in range. You stomp on the gas, the carb cheater sees your AFR needs tweeked and it opens the IAC. When you let off the gas, the carb cheater cannot instantly close the IAC again. Depending on how off your carb was set and how open the IAC was, it may cause you to run lean for a second.
It is meant to be a tuning tool, not a replacement for EFI.

As expected for a new product in beta, the app is a little janky. They are still actively working on it, so its not like you are stuck with abandonware.
 
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After reading this thread and watching the videos this sound interesting. Has anyone else that bought it had time to install and have feedback?
I've been watching Luke on YT for several years so was surprised that he was the one behind Carb Cheater.
 
I finally installed mine.

First impressions are that it is worth it for idle control alone. Currently I have it in “RPM target” mode where it is trying to hold 800 rpm but is limited by how far it can open the IAC valve. I was able to crank the idle-ez closed on my Barry Grant carb and let the carb cheater control the vacuum leak to target idle.

Pretty neat to have a rock solid idle that does not change with engine temperature. Will try a cold start tomorrow to see what it is like.

I like the idea that I can pull up the engine vacuum and AFR on a tablet while I am driving, yet have no permanent gauges.

Would totally buy it again. Might buy a second one just to have around in case he quits selling them or gets bought out.
 
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