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  #1 (permalink)  
Old 10-24-2002, 11:15 AM
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Default Holley Projection Map

I have a projection 900 4DI in my cobra sitting on a very mild 390. Maybe 400hp. That Holey PJ came off of a hot 390 - 600hp. I have not modified settings yet. I was wondering if anyone would be so kind as to throw me a map of their setup so I can review and learn from.

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Old 10-24-2002, 11:57 AM
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I'm still learning about programming the fuel map on my ProJection (and with the weather in the 30-40 degree range, I'm learning slowly)! The following should be taken with a grain of salt about the size of a salt-lick ... remember, I don't know what I'm doing:

If you've got the Holley software, load up a Chevy 350 fuel map. Decrease the "Durration Offset" from it's standard 55 to something around 20. That should get you in the ballpark.

On my 351W (Ford crate motor, 385 hp), I started with the Chevy 350 map and adjusted the duration offset to 10. I'm using a 900cfm unit as recommended by Holley (seemed big to me). Dropping the duration offset from 55 -> 10 reduces the map values by 45% (if I understand the rather vague Holley documentation).

This past weekend I used the Holley software to do a 30 minute sample of the computer's data. End result is that the map is running a bit rich from 1500 to 2500 rpm, a little lean above 2500 (not a lot of samples as I'm keeping the RPMs down until the engine is broken in). Idle is just about right.

Use the monitor function in the software to look at the O2 sensor reading as well as the O2 correction value, they'll give you an idea as to how close the fuel map is set. The fuel injection computer will do it's darnedest to pull the mixture into the correct range based upon the O2 sensor reading.

One of these days ... and well after I figure out what I'm doing ... I'll setup a web page on the tuning of the ProJection. There is just soooooo much stuff you can fiddle with!
Pete K.

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Old 10-24-2002, 12:08 PM
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Thanks. I guess the good thing is that I can save the current map and always go back to where I was... I think Im going to put a 12v converter in my car so I can run with the laptop on and make the changes... I also found a dyno here in the local area where I can get 3 pulls for $60.00. If its not a busy day they will let me tweak and tweak between runs...

Thanks again.
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Old 07-05-2004, 04:48 PM
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Default Fuel Injection Mapping

I have spent the last year learning much more than I thought I ever would about computer programming of EFI systems. EFI tuning can be a very rewarding or frustrating experience depending on your willingness to thoroughly understand the interdependencies of many variables....

I am in the process of getting a class together somewhere in the US with a well known EFI tuning company to put on a beginning and more advanced seminar where actual tuning is learned and results are verified on a Dyno......I would like to know who out there is interested in spending two days (a weekend) for the beginning class and another day for a more advanced class to learn the art of EFI tuning......

e-mail me if you have an interest....I would like to do this in late september to october this year if possible, but that date is flexible depending on how many people are interested..... careful about relying on your O2 sensor for tuning unless it is a wideband O2....regular O2 sensors are not linear through their range of measurements and can be affected by a number of variables....

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Old 07-05-2004, 05:39 PM
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Default Pro-jection maps

Hello all,
I too have been a few rounds with the maps and fine tuning. Holley tech line is worthless beyond selling parts to try( the Easter egg syndrom )
There is a company called ACHARTPRO at 1-336-601-8418 that sells software that adjusts - records- allows real time views and even suggests what to modify. I bought their product about 2 years ago and it has become invaluable and allowed me to do some wild modifications and all while knowing everything was not too lean.
If I can help you with a few of the maps I have created let me know but ACHART PRO makes it easy and was only about 200 bucks if I remember right. Their Tech line is very easy to work with after the purchase even !!! Think his name is Orin ?
Jeff Classic
Manufacturer of the Cobray-C3
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Old 03-09-2005, 07:54 PM
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I need help with Holley 4Di tuning on a chev 350. I have a very limited knowledge of fuel system maps and the Holley manual doesn't supply much help.

I would apreciate anyone taking the time to chat..

I also am looking at the AChartPro software...any feedback on that product would be helpful.

Mark W.

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