GM 2 Bar Map

Information and discussion of EFI hardware and specifications
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Re: GM 2 Bar Map

Postby OZ38 » Wed Jun 12, 2019 3:12 am

antus wrote:The ebay sellers are always reading forums like this and trying to find out how to sell junk for money. If we say look for this or that, they can start saying their product is this or that. Its best to spend the $90 or so from a reputable non-ebay seller for things where low quality copies exist, otherwise it'll always be a risk. Even the reputable sellers get caught sometimes but at least they'll usually stand by their stock and their suppliers should too. Yes, no delco software can accept the 2.5 bar. As you noted, depending on the settings the code is interpreting the 0-5 volt value as 0-100, 0-200 or 0-300 depending on the sensor setting but 2.5 bar needs 0-250 range which nobody has written the software for.

Yes with regards to the 2.5 bar map, I saw it on ebay worded as Delco Style Map suitable for Supercharged, Turbocharged, Motec, Haltex, etc etc. No mention that the 2.5 bar Map is basically useless to most if not all with Tuning software.

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Re: GM 2 Bar Map

Postby OZ38 » Wed Jun 12, 2019 3:15 am

VSRaptor wrote:Who did your kalmaker tune?

I am in WA, so I got Alan Gibbs to do the Map Kalmaker Tune.

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Re: GM 2 Bar Map

Postby Holden202T » Wed Jun 12, 2019 1:38 pm

a 2.5 bar map sensor is not useless, you could totally use it, but you would need to know that the readings are out, and offset all the tables to suit.

if you were dyno tuning and using the trace bubble in tuner pro it would should you which load cell your in, that would really be all you need to know.

the original 2 / 3 bar tunes way back when were just stock tunes with the axis in the tables re-labelled to the right numbering to suit the map sensor used, that is all xdf config, nothing to do with the tune itself.

effectively if you put a 2bar map on a stock tune, 100kpa would actually be 200kpa, and 50kpa would be 100kpa.... the only down side to this was you lost resolution in the tables.

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Re: GM 2 Bar Map

Postby immortality » Wed Jun 12, 2019 3:09 pm

VSRaptor wrote:I almost took the route of going back to the MAF setup until I read somewhere on this forum L67 Getrag had issues and delcowizzid mentioned the LS 2bar will work but the plug is different and everything else is the same. I still got my stock factory MAF so I would imagine there be unbranded cheap MAF out there too. I have the aldl and the nvram with the vs auto L67 on it and it would have been a good opportunity to have my 1st crack at learning.

What do most prefer, MAF or MAP?
I have read that most forced induction engines making over 500 HP require MAP

I don't think you can put a horse power number on when you should swap from MAF to MAP. The old MAF sensors had limitations on how much they could flow and hence how much power they could support and also had a fairly small ID so could become a restriction in flow. Later model factory MAF sensors fixed most of these issues and the current card style MAF's it's not a problem. MAF and MAP each have advantages and disadvantages, tuner/user preference plays a major part in the choice as does the application (bit hard to use MAF on an engine with individual trumpets etc).

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Re: GM 2 Bar Map

Postby antus » Wed Jun 12, 2019 5:34 pm

MAF is also more forgiving of changes that change the airflow as its measuring that directly, unlike MAP where it has a mapping table of manifold pressure to airflow. There is an open challenge on the1s enhanced bins that if you can hit the limits in the code charlay86 will extend it further :) Note that is referring to hitting the grams/s of air limit, not the limit of whatever MAF you have. You are expected to install a large enough MAF and tune to suit. At the end of the day its user preference. As for 2.5 bar map, some after market computers support them. Just make sure everything you have is designed to work together. This includes computer, sensors and also your tuner (if thats not yourself) :lol: When you go outside of this rule things get harder, and nobody wants things to be hard.
Have you read the FAQ? For lots of information and links to significant threads see here: viewtopic.php?f=7&t=1396


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