Speed Density!!
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From: Whidbey Island, Wa.
Speed Density!! I was talking with a couple fellow Tech guys that live local here, and they said after my cam swap, it would probibly be wise to go SD. I am going to take up there advice on it. But what I was wondering is.
What tuner should I go with?
And usually how expensive are they? For a good one that is..
I am going to try and do all the tuning by myself and maybe a helping hand from a fellow tech, that way I can start learning That side of the house.
Thanks.
Lane
What tuner should I go with?
And usually how expensive are they? For a good one that is..
I am going to try and do all the tuning by myself and maybe a helping hand from a fellow tech, that way I can start learning That side of the house.
Thanks.
Lane
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From: Portland Oregon
Sorta depends on the cam profile that you are considering. Persoanally I don't see any gains by going with a SD tune. GM spent millions making the MAF work, and in almost all conditions it works and works well. Having been running a tuner shop for going on 4 years, I have yet to have to convert to a SD calibration on a LSx engine. You can ask around here as I have several customers here in this forum, all from small to large cams.
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From: Whidbey Island, Wa.
The cam I am going to be using is the one in my sig.. See I have heard both sides of using SD or just the stock maf. And I would like to try both, and see witch one I prefer my self. But to begin with I will try SD. And if it is not what I like then I will go back to maf.. Also I don't think I am lucky enough to have some one close in my region, to be able to take my car too for Dyno Tuning. I really don't find driving for more than 2 to 3 hours away very fun to just get tune work done, That may only take 1 hour to do. LOL. So thats why I would like to do everything my self, and also learn it.
Thanks for the reply though its appriciated. Anybody else have any info I could use also.
Lane
Thanks for the reply though its appriciated. Anybody else have any info I could use also.
Lane
I agree with tj. I know some guys with radical setups swear by SD tuning. Personally I have had little luck with it. Every time I got mine close something weird happened & it ran like crap again. You will need to buy at least 1 set of new O2 sensors. If they aren't perfect, your engine won't run right. And tuning it with a wide band won't help. Your PCM doesn't look at that sensor. I have 2 bar HP Tuner that hasn't been put to use yet because the SD part is a major PITA....IMO.
I think SD should only be used on cars that go beyond the MAF's airflow range (like my car for instance). Otherwise you should be able tune the car to make it run right for ANY cam. And when you go someplace with a different altitude, your car will still run right. You can get a feel for what it's like....go disconnect your MAF & see how the car runs.
Flack jacket & flame suit on
I think SD should only be used on cars that go beyond the MAF's airflow range (like my car for instance). Otherwise you should be able tune the car to make it run right for ANY cam. And when you go someplace with a different altitude, your car will still run right. You can get a feel for what it's like....go disconnect your MAF & see how the car runs.
Flack jacket & flame suit on
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From: Portland Oregon
Originally Posted by WAHUSKER
I have 2 bar HP Tuner that hasn't been put to use yet because the SD part is a major PITA....IMO.
I think SD should only be used on cars that go beyond the MAF's airflow range (like my car for instance). Otherwise you should be able tune the car to make it run right for ANY cam. And when you go someplace with a different altitude, your car will still run right. You can get a feel for what it's like....go disconnect your MAF & see how the car runs.
Flack jacket & flame suit on
I think SD should only be used on cars that go beyond the MAF's airflow range (like my car for instance). Otherwise you should be able tune the car to make it run right for ANY cam. And when you go someplace with a different altitude, your car will still run right. You can get a feel for what it's like....go disconnect your MAF & see how the car runs.
Flack jacket & flame suit on
It is a major PITA, and one will spend hours and hours mapping the system. As for your car, what MAF have you tried? Do you know about the 4" LPE MAF that you can put in and all you need to do is to rescale the MAF tables? I have yet to run into a wall with that MAF.
http://www.lingenfelter.com/store/lp..._lpe-4232.html
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From: LT1 land...the "409" of the 90s!
I did not post to this on purpose last night. I was once told because I do not SD tune I have no ckue what I am doing and then I was hounded by that person for being stupid.
I am in TOTAL Agreement with what has been posted so far. SD to me is like an old Holley. it is real easy to get running in a day. Then the next day when weather changes it is not running right again. This is where it getts tricky and takes alot of time.
I feel, like the others here, you must have both sides tuned well to get what you want out of it.
JMHO take it for what little it is worth
I am in TOTAL Agreement with what has been posted so far. SD to me is like an old Holley. it is real easy to get running in a day. Then the next day when weather changes it is not running right again. This is where it getts tricky and takes alot of time.
I feel, like the others here, you must have both sides tuned well to get what you want out of it.JMHO take it for what little it is worth
No Tom, I haven't tried that MAF yet. I've heard some good things about it, and probably should give it a try. Maybe that would be a good reason to finally come meet you, since you have experience tuning them. 
PS And I agree Ellis, you don't know anything about tuning.
PS And I agree Ellis, you don't know anything about tuning.
Last edited by WAHUSKER; Jul 11, 2007 at 10:30 AM.
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If looking for tuning software then I suggest HPtuners. Lane I already have HPT for 98's if you want we can get the tune knocked out in a couple of hours. I'm not the most efficient tuner by any means but we can get it relatively close.
Marty
Marty
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From: Whidbey Island, Wa.
Thanks for the info guys. Its appriciated,
I will deffenitly look up that maf tjwong. thanks!!!
Yeah Marty that sounds like a plan. I don't care if we get it perfect. As long as I can learn something about it, and one day start doing it my self. Hey and also we need to set up a date to go to Mission. I think August 3rd they are doing test and tune... Already talked to the wife about it. So maybe NVME, you and I can take off on that saturday.
Thanks again guys.
Lane
I will deffenitly look up that maf tjwong. thanks!!!
Yeah Marty that sounds like a plan. I don't care if we get it perfect. As long as I can learn something about it, and one day start doing it my self. Hey and also we need to set up a date to go to Mission. I think August 3rd they are doing test and tune... Already talked to the wife about it. So maybe NVME, you and I can take off on that saturday.
Thanks again guys.
Lane
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From: Lynnwood, WA
Originally Posted by WAHUSKER
Do you have a motor lined up yet Josh?
Should've had ellis re-tune the car a little sooner eh? 
Yeah....I know I will spend hours tuning my car with the carb and the next day it won't even run and it's back to the drawing board. Thank goodness mass air fuel injected cars came along because cars were worthless before they came along.
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Originally Posted by Robert56
I agree, no need to go SD. I don't think it's really cracked up to be what some claim.
Robert
Robert
That depends on the application. Looooooooong overlap cams will fool MAF systems too bad. I've actually seen fuel suspended ABOVE the carb at idle on race motors because the cam was causing the air to flow out during overlap. This would fool the MAF into thinking there was twice as much air flowing at idle.
MegaSquirt has code that will use AlphaN mode at idle and then switch to SD at a certian rpm.
Alpha-N - A method of determining fuel requirements for an engine based on throttle position and engine RPM. Because naturally aspirated race engines often produce little or no manifold vacuum, manifold pressure readings are nearly the same at an idle as they are at WOT. This makes tuning the engine in speed/density mode nearly impossible. In these cases, Alpha-N mode is used. Note that supercharged engines should not be run in Alpha-N mode.
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From: LT1 land...the "409" of the 90s!
Originally Posted by NWDragRacer
That depends on the application. Looooooooong overlap cams will fool MAF systems too bad. I've actually seen fuel suspended ABOVE the carb at idle on race motors because the cam was causing the air to flow out during overlap. This would fool the MAF into thinking there was twice as much air flowing at idle.
MegaSquirt has code that will use AlphaN mode at idle and then switch to SD at a certian rpm.
MegaSquirt has code that will use AlphaN mode at idle and then switch to SD at a certian rpm.
I have nothing against SD. Most all after market ECMs use SD as did most Manufactures at one time.
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Originally Posted by NWDragRacer
That depends on the application. Looooooooong overlap cams will fool MAF systems too bad. I've actually seen fuel suspended ABOVE the carb at idle on race motors because the cam was causing the air to flow out during overlap. This would fool the MAF into thinking there was twice as much air flowing at idle.
MegaSquirt has code that will use AlphaN mode at idle and then switch to SD at a certian rpm.
MegaSquirt has code that will use AlphaN mode at idle and then switch to SD at a certian rpm.
See thats the same thing I heard too. That is why I am considering SD. The cam I am choosing has good size overlap, In my opionion. Some may think Different but anything in the high 230 to 240 range is fairely big for a 347.
Lane