Veriable resistor, Potentiameter mod for Intake Temperature control
06-16-2011, 11:24 PM
#1
Senior Member
Thread Starter
Veriable resistor, Potentiameter mod for Intake Temperature control
car: 2000 e55
On Potentiometer: Very interesting results. I came up with this idea because our MAF sensors sit right on the throttle body and get heat soaked pretty bad. On a 80 degree day intake temperatures read as high as 130 which would retard timing. The Idea is to attempt to advance timing. So went to local Radio Shack and matched the resistance of the Intake temperature sensor plus 5000k (5k variable resistor)
istalled it by interrupting sensor wire in the MAF plug. Now i can set my intake temps to read as low as 20 degrees F but im running it so it matches the outside temperatures. So if its 70 f outside , intake will read 70, if its 100 outside intake would read 100.
Did a few runs just with gtech and i must say I was surprised by the results but, 0-60 times went down .1-.2 of a second, that's quite a significant increase in power, but i will have to verify this on track. Don't know what exactly the advance in timing would be with even lower readings but for now Im just sticking to ambient temperature match to be safe.
thoughts?
On Potentiometer: Very interesting results. I came up with this idea because our MAF sensors sit right on the throttle body and get heat soaked pretty bad. On a 80 degree day intake temperatures read as high as 130 which would retard timing. The Idea is to attempt to advance timing. So went to local Radio Shack and matched the resistance of the Intake temperature sensor plus 5000k (5k variable resistor)
istalled it by interrupting sensor wire in the MAF plug. Now i can set my intake temps to read as low as 20 degrees F but im running it so it matches the outside temperatures. So if its 70 f outside , intake will read 70, if its 100 outside intake would read 100.
Did a few runs just with gtech and i must say I was surprised by the results but, 0-60 times went down .1-.2 of a second, that's quite a significant increase in power, but i will have to verify this on track. Don't know what exactly the advance in timing would be with even lower readings but for now Im just sticking to ambient temperature match to be safe.
thoughts?
10-14-2011, 11:14 AM
#2
MBWorld Fanatic!
On my car I just use a 1k resistor before water temp sensor.It sets timing and changes air fuel ratio to 12.5 for max power.It changed my 1/4 mile time from 17.5 to 16.8
10-23-2011, 10:06 AM
#3
MBWorld Fanatic!
Any updates ? Although this sounds great, what about the fact that once you are in boost your intake temperature will be hotter than ambient. I would think tricking the ECU to think the temperature was cooler and thus able to run more timing, would only lead to knock. I have never looked at the ECU code, but would imagine it is much safer to leave the MAF as is....Just my $0.02
10-23-2011, 11:28 AM
#4
MBWorld Fanatic!
If I use a 1.5k resistor I get faint knocking,and my actul times are slower.But using a 1k on my engine is sweet.
I have a resistor that I used on the MAF,it was useless.Tricking the ECU from water temperture sender increases the air fuel ratio,to perfect 12.5 .
I have a resistor that I used on the MAF,it was useless.Tricking the ECU from water temperture sender increases the air fuel ratio,to perfect 12.5 .
10-23-2011, 12:39 PM
#5
MBWorld Fanatic!
Well your 'trick' is a bit different than the OP for several reasons, the most significant being supercharged vs NA. That said, unless you are logging knock, I would not recommend tricking the ECU into false conditions to make it run leaner with the hopes of gaining a few hp. Just my $0.02
10-23-2011, 12:48 PM
#6
MBWorld Fanatic!
No I run richer.Right now I run no resistor until racing season opens up.In March ,after slippery weather is gone I put it back.With resistor she'll spin out easy.
Yeah you can't have it leaned with turbo,supercharger or nitrous.
I hope to add a 75 hp nitrous shot next year,and a wet shot it will be,as my stock injectors will only run at 12.5 afr.
Yeah you can't have it leaned with turbo,supercharger or nitrous.
I hope to add a 75 hp nitrous shot next year,and a wet shot it will be,as my stock injectors will only run at 12.5 afr.
