MAP sensor

[grandam01]

I searched and found something in the 2.4L engine specific discussuion, but I am curious on the 3400.

I have a few bolt ons, EGR delete, 180 T-stat, Milzy reprogrammed PCM, CAI, Exhaust, and the only truely calibrated Granatelli MAF for the grand am ( I went to the GMS shop and J.R Granatelli talked with me about it and we got the stock one on the flowbench and they got all the reading off the grand am). I am running pretty rich just had a dyno done a week or so ago, 150Whp and roughly 185 Ft lb of Torque. They pipe that we used to read the exhaust gases was showing me running at roughly 13.9 and 2 of the 4 passes at 14.0 A/F.

My question is would a 2 bar MAP help me? if not, then should I just go and have my car tuned to meet all the needs of my mods? Well I am also getting a real exhaust too, right now I have the stock tubing no resonator, a glass pack muffler, and it exits out the side in front of the driver side rear tire.

[angrysk8r]

I don't see how a 2 bar map would help you any unless you were boosted, and from what I've read for the people who have used the 2 bar map with boost they have all kinds of PCM issues with it. Really your best bet would be to just get your PCM tuned. To get the best tune though you'll need to do some street tuning with either an hp tuner or dhp powrtuner (then maybe some dyno tuning after the street tune).

[grandam01]

Yeah thats what I thought, well i thought the 2bar MAP might aloow the computer to see more air thus in turn telling it to send more fuel, but I was thinking that I would have to get it tuned, thought that would have been fixed with the milzy tune, I have a buddy who owns a pretty good shop out here so I may just take it to him he uses HP tuners, also to get that fixed it would be more beneficial to do a dyno tune then do some street tuning.

Ok thanks man, helped me answer the question of the night.

[angrysk8r]

Yeah thats what I thought, well i thought the 2bar MAP might aloow the computer to see more air thus in turn telling it to send more fuel, but I was thinking that I would have to get it tuned, thought that would have been fixed with the milzy tune, I have a buddy who owns a pretty good shop out here so I may just take it to him he uses HP tuners, also to get that fixed it would be more beneficial to do a dyno tune then do some street tuning.

Ok thanks man, helped me answer the question of the night.

Yea, unless you're boosted there will be no way for your map to see above atmospheric pressure, all a 2 bar map does is allow the PCM to read pressure above atmospheric, and since your car is naturally aspirated, it will stay at atmospheric or in vacuum no matter what. Basically if you got a 2 bar map it wouldn't hurt anything, but it wouldn't help at all either since you would be using it in the same way as the stock 1 bar. However, if you do have an increase in air flow into the engine, your MAF sensor should pick it up and compensate according to the PCM's fuel tables, and that is where adjustments should be made if they are needed.