negative from going SD from MAF? w/o tune
#21
11 Second Club
iTrader: (2)
That's funny, I lost about 22hp power going to SD. And from a tuner just learning about big cams to one of the best in the southwest. I know all different dynos but a dynojet -491rwhp, twice and a mustang dyno -474rwhp. after SD tune - 468rwhp on dynojet, but that was ok with me because at least the car would stay idling ( RIP ) old friend, lol
#25
ive driven the car a few times.....just cruising and the car wont stay idling when i come to a light or have to stop for any reason....
would that be cause it needs a tune? and/or cause of no MAF? and of course my SES light is on.
Ive also heard it could be cause of the IAC port on the FAST TB's ..they being to small?
IDK......I just need to get the tune and see if Jonathan can take care of it
would that be cause it needs a tune? and/or cause of no MAF? and of course my SES light is on.
Ive also heard it could be cause of the IAC port on the FAST TB's ..they being to small?
IDK......I just need to get the tune and see if Jonathan can take care of it
#26
Super Hulk Smash
iTrader: (7)
When you unplug the MAF, it enables a DTC. It reverts back to the VE table (which is the backup for the MAF in the PCM). However, it goes into limp mode to protect the motor if it senses a MAF failure from what I understand. The idle issue may just be related to the larger TB and no tune.
And for SD tunes, you always need a DTC present - but you can set it to no MIL light - so you should be able to pass a scan test as it looks for the MIL. But it has to happen to fail over the PCM to the VE table. MIL is different than the SES light. You can set no SES light but keep the MIL active. You will fail that test.
As far as Closed Loop vs Open Loop - closed works great with smaller cams. Open is preferred for larger cams, as they wreak havoc on narrowband O2s at idle. The preferred method is for OLSD at idle and CLSD at cruise. Then the O2s can work near stoich and keep the car in a lean cruise state. This is where they are outstanding and accurate.
And for SD tunes, you always need a DTC present - but you can set it to no MIL light - so you should be able to pass a scan test as it looks for the MIL. But it has to happen to fail over the PCM to the VE table. MIL is different than the SES light. You can set no SES light but keep the MIL active. You will fail that test.
As far as Closed Loop vs Open Loop - closed works great with smaller cams. Open is preferred for larger cams, as they wreak havoc on narrowband O2s at idle. The preferred method is for OLSD at idle and CLSD at cruise. Then the O2s can work near stoich and keep the car in a lean cruise state. This is where they are outstanding and accurate.
#27
I havent driven the car that much.....main reason was because i still need a tune and also not having a hood. Well Ive got the hood taken care of but my re-tune is not scheduled til the 14th of April with Tick
I was told going SD from MAF will suck cause SD is somewhat climate specific and where ever I get the car tuned for SD ...climate, elevation and such....that once i bring the car back to almost sea level the car will not run right......idle right or anything.
says that MAF takes care of all that....
any one got an opinion on that?
I cant really afford a new 100mm MAF and im not going to put the stock one back on...that why im going SD
hope i made sense
I was told going SD from MAF will suck cause SD is somewhat climate specific and where ever I get the car tuned for SD ...climate, elevation and such....that once i bring the car back to almost sea level the car will not run right......idle right or anything.
says that MAF takes care of all that....
any one got an opinion on that?
I cant really afford a new 100mm MAF and im not going to put the stock one back on...that why im going SD
hope i made sense
#28
Launching!
iTrader: (1)
I havent driven the car that much.....main reason was because i still need a tune and also not having a hood. Well Ive got the hood taken care of but my re-tune is not scheduled til the 14th of April with Tick
I was told going SD from MAF will suck cause SD is somewhat climate specific and where ever I get the car tuned for SD ...climate, elevation and such....that once i bring the car back to almost sea level the car will not run right......idle right or anything.
says that MAF takes care of all that....
any one got an opinion on that?
I cant really afford a new 100mm MAF and im not going to put the stock one back on...that why im going SD
hope i made sense
I was told going SD from MAF will suck cause SD is somewhat climate specific and where ever I get the car tuned for SD ...climate, elevation and such....that once i bring the car back to almost sea level the car will not run right......idle right or anything.
says that MAF takes care of all that....
any one got an opinion on that?
I cant really afford a new 100mm MAF and im not going to put the stock one back on...that why im going SD
hope i made sense
#29
TECH Junkie
iTrader: (5)
I was told going SD from MAF will suck cause SD is somewhat climate specific and where ever I get the car tuned for SD ...climate, elevation and such....that once i bring the car back to almost sea level the car will not run right......idle right or anything.
says that MAF takes care of all that....
any one got an opinion on that?
says that MAF takes care of all that....
any one got an opinion on that?
The car in speed density still uses many of the temperature and air density sensors, such as IAT, ECT, MAP etc. Thus, the ECM can still account for changes in weather factors. I've been driving my car in 0* bone dry winter air to 90* humid summer days and it drove just fine. While small changes in the tune would be needed in order to run 100% in both seasons, in no way was the car not driveable or it could not idle. Honestly if I wasn't scanning the car to see what it was doing, I would've had no idea that it was running differently from the perspective or just driving it.
If an instance does happen as you mentioned it, the reason behind such drastic changes is due to having a shitty initial tune not the fact that you went to sea level. A tune done quickly can only really deal with weather factors in the present spot. However, a proper SD tune can account for varying weather and altitudes.