okay, i got my cables in today to hook up to the obdI system and am using a datamaster for the scanning. after a good warm up my MAP reading at idle is ~67Kpa. now from what i understand that even with a wild cam, i shouldnt have more than ~18 Kpa. is this right? My car is running crazy rich. i can tell that just from the smell. this might sound like a dumb question considering i put the motor together, but where exactly is the sensor located? i'm assuming that the sensor is bad and am going to try and replace it and see if this helps my running too rich problems. thanks for any help guys.

EDIT: after reading injuneers writeup, i now know where the sensor is located. first off, the local barometric pressure currently is 29.93in. from what i understand, the MAP cannot be higher than the BAR. therefore indicating to me that the sensor has to be bad.

another question, what does the knock count indicate exactly? in a ten minute run (a couple hard runs in there) i accumulated over 50k.

 

You may have read my writeup, but you appear to be having problems with units of measurement. 67kPa is LOWER than 29.93"Hg. 67kPa is about 19.8"Hg. There is no evidence to suggest the sensor is faulty. In case you are looking for it, its the black rectangle, about the size/shape of a domino, held to the top/front/passenger side of the intake manifold. See picture below... its about 1/2" behind the rear edge of the throttle body, and directly under the word "Second" on the shock tower brace:

http://cjcfo.fbody.com/members/injun.../DCP04271a.jpg

Standard atmosphere (barometric pressure) = 29.92"Hg = 101kPa. = 14.7psi(a)

At idle, a stock cam will generally pull about 20"Hg vacuum. Vacuum = BAR - MAP. So.... a stock cam will show a MAP reading of approx 10"Hg = 34kPa.

You will never see 18kPa on any intake manifold at idle - only on heavy closed throttle decel. You will see numbers closer to 50kPa with moderate cams, and maybe as high as 65kPa with more radical cams (I'm talking things that are still somewhat "streetable".)

Your idle MAP will be determined by the cam (I don't know the specs on the LE2 - why don't you ask Lloyd or Bret what MAP you should see?), and how well it is tuned. Ignition timing, idle speed and A/F mix will affect the vacuum.

 

65 KPA is not uncommon for a cam as big as yours. Ambient factors such as temperature will also influence that, but 65ish is OK for that cam.

 

not to high jack. i recently put my motor back together....ported lt1 heads, 2.00 intake, 1.56 exhaust valves. joe o cam 230/240 ish .570/.540 on 111

i'm pulling 75 kpa at idle, replaced the map sensor, grommet, pcv, tried new vacuum lines and still get dtc33 at idle, not sure if this is normal for the size of cam. if so, can it be tuned to not throw the code?