I put the stock airbox back on.

My lean condition at WOT went away, probably due to less airflow. :mad I'm still too rich at base, with LTFT's around -8 to -10, but I'm right where I should be at WOT.

So anyway, I guess I'll try the MAF Translator when I get more time to mess with the car. I'm just tired of dealing with it for now, and I have had enough of the rattle. And, yes, I felt a big difference in throttle response. :cry :cry

F

 

Normal. Time & again everyone learns this.

If you plan to change your intake with Filter, MAF Ends, TB, etc.. Bridge.. You'll need a MAFT & AutoTap and learn to tune her. Worth it to tune your car right and the mods are good ones. But naw, you can't just slsap them on like most people do.

 

I assume the throttle response was worse, not better, after the stock airbox went back on? :eek:

I had the same problem (occasional pinging at WOT and/or high gear/low speed/heavy load) -- Donaldson BlackWing (no cold air), and found that frequent doses of Sunoco 94 helped a lot. :smash:

 

BTW, drove the car for ~100 miles today, and I just HAVE to go back to the cold-air intake. Car just doesn't have any of the 'kick' it had before - knock or not.

Guess a MAFT is in my near future.

F

 

Why would an air lid or filter cause a lean condition? Yes, it frees up more airflow, but all the flow is going through the MAF sensor, and therefore being measured. I can understand how a modified MAF or MAF ends could cause a lean condition, by changing the diameter of the measuring device without changing the calibration, but I don't understand how a mod which reduces restrictions upstream of the stock MAF could make it run lean. A clean stock filter vs a dirty stock filter could be considered an "intake mod" from the MAF's point of view...are we saying that the dirtier your filter gets, the richer the car runs?

 

My bad for not reading the post completely. I guess the filter shouldn't affect things. Same size MAF for the stock MAF sensor. I thought the MAF ends were tweaked. Stock we run too damn rich anyhow, so that's prob what he was seeing.

 

There's some cooler air floating around these days. Are you sure the knock didn't just disappear because you ran it on a day with cooler temps?

I have a Blackwing and ported MAF and the only way I could get rid of knock was to get a MAFT and tune it. I ended up having to use +10% rich for the WOT setting to get rid of knock completely.

Mike

 

Flintstone,

Add some NOS brand Octane Boost and see if the ping goes away. You can also lower the odds of detonation by installing a cooler thermostat like a 160 F.

 

I have tried the NOS brand twice and both times the results were not good, still had knock. the104+ plus brand performed better and they are honest in it says on the bottle to only use 1 bottle for a tank and then only repeat between 3 tankfuls.

A 160 degree stat will not meet the valid warmup cycles needed by the PCM to clear PCM codes esp if used in the colder weather timeframes.
You can maintain a stock stat and use a MAF translator to tune out knock and maintain the temps needed for functions like O2s and PCM I/M tests.

John


[Modified by team-zr1, 1:08 PM 9/17/2001]

 

Listen to John, he knows what he is saying.
I have been working with him for about a week now.
I have a Y2K A4, with RM racing twins, aftermarket MAF, high volume duct and boot, Corsa Indy's, NGk TR-55's, Magnecor 8.5mm wires.
I got a MAFT and the EASE scan tool and the LTFT's and O2's were both lean so I have my base set at 10% rich and WOT set at 4% rich. The punch @WOT before was good but now it is just nasty. I was punching it out of slow corners at 15 mph in 2nd gear and was having to feather the throttle to keep from getting too much wheel spin. I still have a way to go but I did beat my best time at the track by 4 seconds yesterday. I still can't catch the Z06's but I am still running the GY EMT's.

 

John - what temp stat do you recommend??

 

Red Rocket

You beat your previous time at the track by 4 seconds, I don't think so unless you really do have a rocket. You must mean 4 tenths of a second!

 

I'd say go no lower then like 178 degrees, if you went with a 160, then during colder weather the car would ever see 200 degrees ( as worse case) and thus the valid warm- cycle as per OBD-II would very seldom would be achieved.
Keep in mind a PCM error depending on the type it is takes up to 80 trips to be purged out, if the engine never meets the valid rules to be counted as a valid warm-up cycle or trip that error will not be purged until the valid trips have been done.

On the other side, you really need to be doing PCM scans/monitors for then you know if you really need to be forcing the engine cooler or not.
Why force colder water temps if in fact the makeup of your engine is running too rich, lowering the temps will just make it even worse.
Also the richer the engine is runing the more timing is taken out which also delutes your torque. These LSX are designed to perform best with the smog temps required.
I'd say before going with a colder stat to first use a MAFT to optimize PCM fuel/timing tables to tune knock out which assures you best performance and only if you cannot tune out knock then drop stat open time.
That's what this whole tuning project has been about, 30 C5s I know of now have tuned knock out and had better tuning of PCM with just a MAFT.

John

 

Red Rocket was not on a drag strip, it was on a auto-x course and by tuning in he reduced knock, gained overall timing which got him his torque back which allowed him to pull very well through that type of course, so the 4 seconds reduced were lap times.

John

 

quote:
--------------------------------------------------------------------------------
Red Rocket
You beat your previous time at the track by 4 seconds, I don't think so unless you really do have a rocket. You must mean 4 tenths of a second!


--------------------------------------------------------------------------------
I think i mentioned i was coming out of 15mph corners.
Does you drag strip have corners?

 

Rocket, I read your post in full as well and automatically assumed it was 1/4 mile time! As my daughter says: "Real drivers go straight to the finish line" . It takes skill to drive straight & round/road courses.