Switching to Speed Density
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Switching to Speed Density (UPDATE) UPDATE:
So I just got my car back together after the Intake and Fuel Injector swap. Here are some pics of the MAP Sensor in case anyone was wanting to see for themselves.
Cobalt 2 BAR MAP Sensor (GM Part#: 12615136)
Side-by-Side Comparison:
This picture shows the tabs that need to be removed to be able to fit in the intake. The electrical connector is a direct fit. No need for any extensions or pigtail converters.
Since I have a 98 PCM, I can only got up to a 2 BAR OS. 99+ should be able to use a 3 BAR MAP and a 3 BAR OS. Since I'm only running 4 PSI at the moment, I'm okay with the 14.7 PSI max I can run with a 2 BAR OS. If I want to go higher, I'll either need to get a new PCM or a completely different computer (EBoost or Big Stuff). Hope this helps everyone that had questions about switching over to Speed Density. Hopefully have the car tuned within a few weeks.
So I just got my car back together after the Intake and Fuel Injector swap. Here are some pics of the MAP Sensor in case anyone was wanting to see for themselves.
Cobalt 2 BAR MAP Sensor (GM Part#: 12615136)
Side-by-Side Comparison:
This picture shows the tabs that need to be removed to be able to fit in the intake. The electrical connector is a direct fit. No need for any extensions or pigtail converters.
Since I have a 98 PCM, I can only got up to a 2 BAR OS. 99+ should be able to use a 3 BAR MAP and a 3 BAR OS. Since I'm only running 4 PSI at the moment, I'm okay with the 14.7 PSI max I can run with a 2 BAR OS. If I want to go higher, I'll either need to get a new PCM or a completely different computer (EBoost or Big Stuff). Hope this helps everyone that had questions about switching over to Speed Density. Hopefully have the car tuned within a few weeks.
Last edited by Pat-Man; Mar 24, 2009 at 11:31 PM.
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Was wondering if something like this would work:
http://cgi.ebay.com/ebaymotors/GM-2-...4506.m20.l1116
http://cgi.ebay.com/ebaymotors/GM-2-...4506.m20.l1116
I just got mine to run on 2 BAR SD today. I had to figure out that I bought 2 BAD MAP sensors so we went with the old style (P/N 12247571) & built a wire harness adapter for it. Folltow the HP T instructions to get started, and then copy your VE table into the new one down low & go from there. We did that & the car started right up & idles great....still much to tweak tho. 
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I just got mine to run on 2 BAR SD today. I had to figure out that I bought 2 BAD MAP sensors so we went with the old style (P/N 12247571) & built a wire harness adapter for it. Folltow the HP T instructions to get started, and then copy your VE table into the new one down low & go from there. We did that & the car started right up & idles great....still much to tweak tho.
http://cgi.ebay.com/ebaymotors/Elect...81310011r33215
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You have a plethora of sensors to choose from. I believe all of the part numbers are in one of the sticky's in this section. And there is a thread over on the HPTuners forum I just can't find either of them right now, lol. $85 seems a little steep try one of Steve's http://www.lsxtune.com/shop/product_...roducts_id/441
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I got a 2 bar that looks like the one that was removed. I had to grind down a tab because it had it on both sides to make it fit. If I'm not mistaken, it was out of a supercharged cobalt. So don't quote me on that, but I'm sure you can call a gm dealership and find out.
As for the tune, you have to have HP Tuners, because EFI live doesn't offer a 2 bar OS. Also, when I changed the map to the 2 bar, it wouldn't start until the 2 bar tune was loaded. Just a little heads up in case you are going to have someone else tune it and you have to drive there.
As for the tune, you have to have HP Tuners, because EFI live doesn't offer a 2 bar OS. Also, when I changed the map to the 2 bar, it wouldn't start until the 2 bar tune was loaded. Just a little heads up in case you are going to have someone else tune it and you have to drive there.
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Thanks for all the information guys. My tuner is local and uses HP Tuners. We went through my car's current tune, and I'm maxing out the MAF with my 408 and T76. I figured my first steps to take next would be to convert to SD and then retune for the 60# injectors I'll be getting soon. We drove the car after some tweaking and my stock 28# injectors are over 110 Duty Cycle at 4200 RPMs. This is only on 3 -4 PSI. Thanks again!
Thread Starter
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You have a plethora of sensors to choose from. I believe all of the part numbers are in one of the sticky's in this section. And there is a thread over on the HPTuners forum I just can't find either of them right now, lol. $85 seems a little steep try one of Steve's http://www.lsxtune.com/shop/product_...roducts_id/441
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yes. 
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
I have the wiring adapter that RooRnZ28 linked. It's brand new, and I don't need it (went with a MAF tune). PM me if you're interested. It's just collecting dust in my garage.
