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Discussion Starter · #1 ·
What are the ramifications of using a Mass Air Flow sensor from a 96 Corvette or Camaro on a stock 96 Impala?

Discussion Starter · #2 ·
please don't post the exact same question in 2 different sections...

and the only thing you need to do to use that MAF properly is reflash the PCM in the car with the correct MAF sensor tables.

Discussion Starter · #3 ·
First, I would like to apologize for the breech in forum etiquette. I am a novice and no harm was intended. Second, I want to thank you for the advise. I have a unique situation. I am not a Impala owner. I do have a 96 Impala drive train that I have implanted into an 83 Jaguar XJ6 sedan. This was a very successful conversion and I am extremely happy with the way that it turned out. I don't think that I could have selected a better drive train for this project which is a testament to the power and engineering of the Impala platform. American brawn in a British body. The link below will take you to pictures of this vehicle that are posted on a Jaguar web site.

I acquired the 96 Impala drive train from a wrecker. It was complete with the 4L60E transmission, accessories, MAF, PCM and harness. Small block conversions are very popular with these older Jaguar sedans and XJS coupes. The LT1 is the latest and most modern variation of this conversion. I assembled an air induction system for this project that is unique. As far as I know this configuration has not been configured before on a Jaguar conversion. Thanks to the crowned contour of the hood, I was able to install a modified K&N filter above and forward of the radiator. The intake ducting and MAF sensor came right out of a 96 Corvette. I did not give a lot of thought to the calibration of this MAF relative to the PCM until I set off fault codes P0171 and P0174 for lean conditions. At this point, the probable cause is that more air is entering the engine than is indicated by the PCM due to the non-stock MAF sensor.

I appreciate the advice to modify the MAF signal tables in the PCM. If you have advice on how to perform this modification I would really appreciate it. I was also wondering if there are other options to correct this condition that do not require rework to the stock PCM programming. Since I do not know much about this process, I am a bit apprehensive about sending the PCM off to someone without a full understanding of what the results may be.

The following list has a few ideas for alternate options to deal with this condition:

1) Install the correct Impala MAF sensor. The problem with this option is that the rubber duct parts are designed to match the Corvette/Camaro MAF diameter, not the smaller Impala MAF. The stock MAF is obviously more restrictive due to the smaller diameter.

2) Install larger fuel injectors. I am currently running Ford Motor Sport 24 lb/hr injector. If I switched to FMS 30 lb injectors, a greater amount of fuel will be delivered for a given injector pulse width. This would allow the long-term fuel trim to return back closer to the mean and away from the limit that set the fault codes.

3) Install an adjustable fuel pressure regulator with the goal of increasing the nominal pressure to deliver more fuel for a given injector pulse width. This essentially does the same as option 2.

Feedback on these options would be greatly appreciated. I am not an expert on this engine and its management system. This is why I posted my question on the forum. I figured that it would be best to solicit advice from the experts.

Discussion Starter · #4 ·
Now that I also know you're not running stock injectors...DEFINITELY get the PCM reprogrammed. The ford 24 lb/hr injectors are actually not the same flow rate as GM 24 lb/hr injectors...Ford rates their injectors at 39 or 39.5 PSI (I forget which) and GM rates theirs at 43 or 43.5 PSI (again I foget which) the ford injectors are a pintle style while the GM injectors are a disc they work with different offset tables to function as best they can.

So my advice to you is to send the PCM out to be programmed...all I would have them change is the correct MAF sensor tables and then adjust the fuel injector constant as well as offset tables for the ford 24 lb/hr injectors.

The Impala's MAF sensor is fine for a stock sized LT1...I don't think the larger MAF is worth it until a higher power level...that said though, you already have the MAF and you already have an air intake fabbed up for the car that you like, and it fits the corvettes MAF diameter, since in my opinion you have to get the PCM reprogrammed for the fuel is abuot 4 more seconds of work for a programmer to copy the MAF Tables from a stock vette program over to your cars program as keep the larger MAF in there...once the PCM is programmed for it, it will run fine.

Right now your lean condition is both a result of the MAF AND the non-stock GM injectors.

I figured you weren't meaning any harm by the double post...thats why I just kept it to one line there, sorry if I came across as harsh or something (some of us who've been on the forum for a while can do that now and then, I apolgize).

Sounds like a heck of a to post any pictures? I recently saw a Jaguar (not sure what kind other than fairly new) with a GMPP Ramjet 502 installed in it...the license plates on the car (which was meticulously clean) read XJSS...I thought that was pretty cool.
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