3800 Small update on the AC IC

[LP 3800]

I finally got rid of that massive 3.0" pulley. I was running it with 23.5 degrees of timing( I ran out of knob) and no knock yet. So I finally got my 2.6" in the mail. I threw it on last night and.....holy crap. This thing pulls so hard. I am seeing 14lbs of boost with 21 degrees of timing and O2 readings in the 700's still . I am still working out the lean situation.
I only saw .5 degrees of knock when I had it up to 22 degrees of timing. Not bad for running way lean.
I know it is cold outside, but that is the beauty of the AC IC. Of coarse the outside temp of the air helps( I cannot change that for now) But my water temp does not depend on the outside temp at all. It is completely enclosed from the outside temp. I still have a lot more info to pull from this thing, but I just wanna keep the club posted on the progress I making and the fun I am having with it.
I have a 2.4" at home I will put on pretty soon
But for now I am ripping the tires at 60MPH so what is the point

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[beyerch]

Hey,

couple things to note, and no this ain't no slam.

#1 - The Minimum Air Temp to allow the AC to operate is 5 C. Unless you have this modded, there's no way the AC/IC was working last night or today.... 5C = 41F. I don't think we changed that in yours yet, but I could be wrong. On the other hand, maybe mike changed that and your running that computer, I don't know?

#2 - This very cold weather will let you do crazy things with the boost. BE CAREFUL in the spring time when it warms back up. You will want to start back over with a 3.25 pulley or so and evaluate from there.

#3 - As far as the lean goes, with that much airflow you should be lean but not that lean. We can discuss some options when i come over... If you were running mike's pcm i know they run leaner than ours and with this weather and that much airflow, you would see some low #'s. I wouldn't expect to see o2's with our pcms unless you had a physical issue somewhere.

Charles

 

[LP 3800]

You are the one who changed the AC temp on my car last time I was over
All those nights in the garage that you have, probably just blend together now
I think you set it to -44F for me. I know about the cold weather helping, but I wish I could change that. I will definitely be watching the knock gauge while experimenting.

 

[imported_snoop]

dude your car is a fu**** beast! it sounded toooooo good when you started it. watch those 02's though that is scary. did you get those injectors yet. did you get them installed. last night i hit 13.5 pounds of boost. the car pulled like none other. i could only imagine what it is like being in your car. congrats but at the same time, be careful. if you need anything, you got my # . talk to ya.

 

[beyerch]

Originally posted by LP 3800@Jan 7 2004, 10:26 AM
You are the one who changed the AC temp on my car last time I was over
All those nights in the garage that you have, probably just blend together now
I think you set it to -44F for me. I know about the cold weather helping, but I wish I could change that. I will definitely be watching the knock gauge while experimenting.

heheheeh

yeah i kinda thought we were talking about it, but i'll be damned if i remember actually doing it ..... sorry one too many 3am tuning sessions has blended them all together.....



heh

 

[gtphale]

Charles I think there is something physical wrong with his car. Even in warmer temps he only see's O2's in the 700's. fixing the tank helped some but not totally . Did you ever fix your temp sending unit yet Brian? and your sc bypass? Heard that temp sending unit figures into the fuel air mixture do you know anything about that Charles?

Even with the mini afc we couldn't get his O2's to come up. We richened the car upto 116 % with no differance.

 

[sweetness]

Im not sure if you have replaced your injectors at all, but .700 with a 2.6 pulley sounds like you have run the (stock) injectors to their max. Sounds like your I/C is working awesomely though.

BC

 

[LP 3800]

I actually installed it today. I have not even checked if it worked yet. I will fill you in when I know.
I did not replace the bypass yet, but I have it at home. I will get to it tomorrow I am sure. I will update you if there is any change in the o2's after I do that

 

[CoolGTX]

Originally posted by LP 3800@Jan 7 2004, 07:35 PM
I actually installed it today. I have not even checked if it worked yet. I will fill you in when I know.
I did not replace the bypass yet, but I have it at home. I will get to it tomorrow I am sure. I will update you if there is any change in the o2's after I do that

installed...what? the temp sensor?

 

[LP 3800]

Yes the ECT sending unit.

 

[beyerch]

Ummmmm

You have an exhaust leak ?

If so air, could be getting in there which would lean out the O2 sensor.

 

[LP 3800]

I am pretty sure I do have an exhaust leak. I will look into that

 

[sweetness]

sorry to hijack the thread. I have been seeing a lot of KR while running 3.25" (11*+) and mild KR wihile running a 3.4" (4-8*) pulley. I also KNOW i have a leak in my crossover on my S&S headers. My 02's are consistently in the .90 to .93 through out the rpm band. Could having an exhaust leak be causing the KR? maybe from the sound coming out of the piping being close to the knock sensor??

the last time I tapped my car I wasn't running with a DHP. I have one now, and it is probably helping a little, but my problems didn't seem to be associated with my O2 levels. It was a false knock, at least a typical one, because it isn't spiking and falling. it is consistent. I would really like some ideas on what you all think is going on.

BC

 

[superchargedgp]

Originally posted by sweetness@Jan 8 2004, 11:39 PM
sorry to hijack the thread. I have been seeing a lot of KR while running 3.25" (11*+) and mild KR wihile running a 3.4" (4-8*) pulley. I also KNOW i have a leak in my crossover on my S&S headers. My 02's are consistently in the .90 to .93 through out the rpm band. Could having an exhaust leak be causing the KR? maybe from the sound coming out of the piping being close to the knock sensor??

the last time I tapped my car I wasn't running with a DHP. I have one now, and it is probably helping a little, but my problems didn't seem to be associated with my O2 levels. It was a false knock, at least a typical one, because it isn't spiking and falling. it is consistent. I would really like some ideas on what you all think is going on.

BC

PUT an intercooler on it, it will take care of your problem

 

[sr71_rgl]

I wouldn't think it's false if it changes when you swap to a larger pulley. Sounds like it's real knock to me, but I'm suprised you're getting any w/the SS headers and a 3.4". Have you noticed your coolant level dropping ever so slowly? Maybe you've got something leaking coolant into your combustion chambers which is lowering your octane? Try the race fuel/torco test to see if the KR goes away.

 

[sweetness]

i never thought about that. ill check into it. I wouldn't be surprised. I'm not going to put an intercooler on it, yet. the supercharger has to go first. Once I have my project up and running it will be intercooled.

BC

 

[beyerch]

11 KR with 3.25, headers, and 02 in/around 930 can't be right.

I run the 3.25 on my car with no headers, just a cone, and pcm, and in this typeo f weather i'm seeing my 1 degree KR. On hotter days, it will spike to 7 at times, but normally even the the summer i'll see 3 - 5 at WOT.

It may vary with the pulley because you have a combination of real and false? I'm sure you should see some KR, but 11 is quite excessive for that setup.

One thing to remember about the 02 sensor; however, is that the number is an average. You could very well be lean on one cylinder and very rich on the others and your average would look ok.

You could have justin flow the injectors?