MAF or SD tune?
MAF or SD tune? I recently installed an HKE built 402 into my car which consists of the following:
Wiseco-8cc pistons
TFS225cc heads
252/259 .624/.624 110+4
Victor Jr Intake
Intake elbow
NW 90mm TB
TSP 1 7/8 LT headers
TSP off-road Y-pipe
42# injectors
Which route do you guys think I should go and why? I have searched several different threads about this and I keep leaning towards the SD tune, however my tuner doesn't have a lot of experience tuning in SD and he was told by someone at HPTuners that in order for the tune to work the car will have to operate in open loop all the time.Is that information correct?He was also told that with SD tuning we will need several different tunes depending on weather conditions, which I believed until I read that is only true if the tune is off to begin with. How should he go about trying to dial in the tune on the car? All of the walk-throughs I have read about on tuning in SD talk about logging the LTFT but we disconnected the rear O2's so that isn't an option at this point in time. I would just like the car to be drivable so I can break in the motor, clutch and rearend. Once that is taken care of then we should be able to fine tune the car later.Any help is appreciated guys.
Wiseco-8cc pistons
TFS225cc heads
252/259 .624/.624 110+4
Victor Jr Intake
Intake elbow
NW 90mm TB
TSP 1 7/8 LT headers
TSP off-road Y-pipe
42# injectors
Which route do you guys think I should go and why? I have searched several different threads about this and I keep leaning towards the SD tune, however my tuner doesn't have a lot of experience tuning in SD and he was told by someone at HPTuners that in order for the tune to work the car will have to operate in open loop all the time.Is that information correct?He was also told that with SD tuning we will need several different tunes depending on weather conditions, which I believed until I read that is only true if the tune is off to begin with. How should he go about trying to dial in the tune on the car? All of the walk-throughs I have read about on tuning in SD talk about logging the LTFT but we disconnected the rear O2's so that isn't an option at this point in time. I would just like the car to be drivable so I can break in the motor, clutch and rearend. Once that is taken care of then we should be able to fine tune the car later.Any help is appreciated guys.
I recently installed an HKE built 402 into my car which consists of the following:
Wiseco-8cc pistons
TFS225cc heads
252/259 .624/.624 110+4
Victor Jr Intake
Intake elbow
NW 90mm TB
TSP 1 7/8 LT headers
TSP off-road Y-pipe
42# injectors
Which route do you guys think I should go and why? I have searched several different threads about this and I keep leaning towards the SD tune, however my tuner doesn't have a lot of experience tuning in SD and he was told by someone at HPTuners that in order for the tune to work the car will have to operate in open loop all the time.Is that information correct?He was also told that with SD tuning we will need several different tunes depending on weather conditions, which I believed until I read that is only true if the tune is off to begin with. How should he go about trying to dial in the tune on the car? All of the walk-throughs I have read about on tuning in SD talk about logging the LTFT but we disconnected the rear O2's so that isn't an option at this point in time. I would just like the car to be drivable so I can break in the motor, clutch and rearend. Once that is taken care of then we should be able to fine tune the car later.Any help is appreciated guys.
Wiseco-8cc pistons
TFS225cc heads
252/259 .624/.624 110+4
Victor Jr Intake
Intake elbow
NW 90mm TB
TSP 1 7/8 LT headers
TSP off-road Y-pipe
42# injectors
Which route do you guys think I should go and why? I have searched several different threads about this and I keep leaning towards the SD tune, however my tuner doesn't have a lot of experience tuning in SD and he was told by someone at HPTuners that in order for the tune to work the car will have to operate in open loop all the time.Is that information correct?He was also told that with SD tuning we will need several different tunes depending on weather conditions, which I believed until I read that is only true if the tune is off to begin with. How should he go about trying to dial in the tune on the car? All of the walk-throughs I have read about on tuning in SD talk about logging the LTFT but we disconnected the rear O2's so that isn't an option at this point in time. I would just like the car to be drivable so I can break in the motor, clutch and rearend. Once that is taken care of then we should be able to fine tune the car later.Any help is appreciated guys.
Good Luck
Which way is so opinionated (is that a word?) everyone has their own preference. I run SD all the time which is open loop, no trims all the tome. My 02's are there for chin ups when the car is in the air, but then Im in FL no emissions. CA if a lil different. If thats not an obsticle then I would go SD. If ur tuner doesnt know how to dial in a map then i dont know if he's a tuner. Its really not that difficult if you grab a HPT or EFILive. Masport Speed sells HPT with a book on tuning, you will need nothin else. Plus there's always someone on here to answer questions... or start an arguement. LOL
Good Luck
Good Luck
Rear O2's are not necessary for logging your long term fuel trims.
I'f you've got a good MAF that isn't a restriction for the new engine, then a proper MAF tune (including the VE tables and MAF tables) will probably run really well...if your MAF is a restriction, or isn't functioning properly, SD tuning sounds like a very good option depending on your tuner and his/her experience/competence. In my opinion any good tuner, can tune either SD or a MAF car...anyone who can't, isn't a good tuner.
LOL see what I mean.
Mr. Mike, I prefer to tune SD in OL, if thats OK, thank you and who brought up rear 02s, they usually get tossed with the cats and I dont believe he has cats. But I could be wrong...
Mr. Mike, I prefer to tune SD in OL, if thats OK, thank you and who brought up rear 02s, they usually get tossed with the cats and I dont believe he has cats. But I could be wrong...
Last edited by 3fingas; Jul 4, 2009 at 06:42 PM.
With that radical a cam you may have MAF related problems
at the low end. But a MAF tune will be more consistent against
weather and so on, than speed density unless you spend an
awful lot of time working the temperature compensation.
I would go the SD route first, then lay the MAF back on top
and see if you can gain consistency without losing drivability.
at the low end. But a MAF tune will be more consistent against
weather and so on, than speed density unless you spend an
awful lot of time working the temperature compensation.
I would go the SD route first, then lay the MAF back on top
and see if you can gain consistency without losing drivability.
I'm not trying to argue with you, but if you read the way you worded your first post, you specifically said speed density is open loop "I run speed density all the time, which is open loop", and thats not true. The original poster sounds like he doesn't know a lot about tuning, but is trying to learn, so I was just trying to help him understand that speed density and MAF can both run closed loop, your wording, though I'm pretty sure you did just mean your own car is running OLSD, could make a beginner think that speed density cannot run open loop.
Like I said, not trying to start an argument, just trying to make sure someone who's clearly trying to do some research and learn, isn't misunderstanding some fundamentals.
