Has anybody ever had any experience with the Carb Cheater? Understand the vacuum spacing plate raises the carb 1/2”. Curious what kind of clearance that would leave. Plan on Running an Edelbrock Performer intake with holley square bore and guessing a 14x3
air filter with 1” drop. I had the Carb Cheater recommended to me ( his utibe videos seem good), but at nearly 500 bucks, I would like to hear from somebody with experience with it and know of it is worth the money and if it will fit a standard Vette hood. Any help put there?

 

I "gaggled" it. If'n you have an extra $500, get one. It seems Ethanol throws it off though.

 

For checking air cleaner clearances, etc, get some modeling clay. The stuff made for kiddies works fine. Put a clump on the air cleaner lid and close the hood...voila, your clearance is revealed.
Works for other alignment issues also. For hood. align, make a flat sheet of clay. Position it over opening of the female hood latch and slowly close the hood...you want to see the male hood latch pin positioned in the center of the female hood latch opening.

 

My understanding is it's a controlled vacuum leak and if the carburetor is correctly setup to start with there is no gain. Below is from another site discussing it.

The Carb Cheater's claim-to-fame is the ability to hold closer to target fueling, with controlled incremental bypassing of air into the manifold to lean the current mixture, per your programmed target values, referencing a wide-band O2 sensor. This should allow maintenance of a target AFR much closer under varying but fairly stable conditions than a traditional carburetor tune to the same values. It is active Lambda control, reactive to current conditions. Very simple but cool concept, and possibly quite useful to certain users in certain conditions.

While the common rebuttal is that we should just tune our carbs leaner or properly to best power and best economy in the first place, thereby covering all the needs; the CC has the capability (I have not tested CC, but am very familiar with the process) to maintain that tune closer with that responsive adjustment of air. This would indicate the most to gain is by users with large changes in conditions, from fuel grade, blend, altitude, temperatures, etc under fairly stable conditions (typically cruise). Stable, as the response is delayed after combustion (so it is limited in quickly-changing conditions), and the stepper motor idle air valve from '70s-'80s GM EFI is relatively slow to adjust airflow.

All good. It is important to recognize the function is only from a presumably richer tune, and leaning to a target value. This means tuning to achieve a tune incrementally rich for any conditions, so the CC can add air to lean to the target. It also means tuning to find what that target should be for your car, engine, fuel, etc, and the ignition timing to support that AFR safely. It could be helpful to many, to learn some principles, concepts and examples of methods to safely and accurately find what those values could be, and why.

 

They seem like a cool invention, but it seems like the “better” solution would be a correctly tuned carb or just making the full jump to fuel injection with O2 sensors to control the mixture.

 

As I have stated earlier elsewhere, you still have to a have a basic working knowledge of the carburetor circuits and what you are doing or need to do to tune it. I havent found their written instructions on a base carb tune or setup but with the directions stating it can make your carb run richer, then it must be tuned to be running fat initially, then the CC leans out the AFR by adding the controlled air leak. They state that when the engine is under load it will make the AFR richer by closing the vacuum leak. When set up properly the power valve in a holley carb will do this.

This system will not tune your carb for you. It can provide a lot of information so you can tune your carb actually knowing when it is rich and when it is lean. You can do this yourself with just the AFR gauge and your tachometer. But you will have to tune for cruising with no load to cruising under load at a specific rpm glancing at your AFR gauge and the RPM at the same time so you know what circuit in the carb you are using. Its challenging and requires you to be aware of everything that is going on. If this system does what it says it will give you a data log that you can go back and look at and it will tell you what rpm and speed ( provided you have a GPS signal ...more $) you where at when you had a specific AFR event. This would work best with short drives so you can relate specific events to the AFR you need to address. But the Data lOg requires you to have aphone that it will work with or buy a tablet that is compatible...( more $)

IF you have an older carb and you cannot change Idle air bleed, high speed air bleeds or idle fuel restrictors easily, it may be a decent choice in that it can cheat using the controlled air leak to work around where these jets would normally need to be adjusted to perform in a certain rpm range. Its not going to be cheap but it is possible it can make it easier for a person that doesnt fully grasp all the little nuances of a Holley carb to make it easier to tune.

If you live at the bottom of the Colorado foothills and climb up to Denver daily then it could help the car run better at different elevations. I havent used it or own one but I have tuned with a AFR gauge and there just isnt a better tool for tuning than that gauge.

 

Recommendations on a trustworthy AFR gauge?

 

The good ones all use a Bosch O2 sensor. I like my Autometer analog gauge. I used to use an AEM wide band digital that worked well.
Heres Whst Summit has in stock

https://www.summitracing.com/search?...ord=o2%20gauge