MAFless/Speed density tuning questions within
02-10-2003, 08:25 AM
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MAFless/Speed density tuning questions within Hi guys,
I have a 98 PCM with stock fuel system and stock descreened MAF. (360ci motor, Stage 1.5 heads, 230/230 112LSA cam)
I want to remove my MAF from the equation. What are some things I need to look out for?
I will be doing WOT tuning on the dyno with LS1 edit.
Anything in particular I need to look out for?
Any particular codes I need to disable?
Thanks all,
Chris
I have a 98 PCM with stock fuel system and stock descreened MAF. (360ci motor, Stage 1.5 heads, 230/230 112LSA cam)
I want to remove my MAF from the equation. What are some things I need to look out for?
I will be doing WOT tuning on the dyno with LS1 edit.
Anything in particular I need to look out for?
Any particular codes I need to disable?
Thanks all,
Chris
02-10-2003, 09:10 AM
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Re: MAFless/Speed density tuning questions within I hope you get some replies here, Chris... I've been wanting to try the same thing myself, but I haven't been successful in finding any real information, other that "you have to edit the VE tables." <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'm a little hesitant to just remove the MAF from the car, and strap it to a dyno and start playing with VE tables...
I know there are some folks doing this with success in Austrailia.
I'm a little hesitant to just remove the MAF from the car, and strap it to a dyno and start playing with VE tables...
I know there are some folks doing this with success in Austrailia.
02-10-2003, 10:09 AM
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Re: MAFless/Speed density tuning questions within Since the MAF gives you the actual airflow you can drive around, record MAF, MAP, RPM, IAT, and calculate the actual VE at each point (since you can get theoretical from the RPM/engine size and actual from the MAF). From this you could create a VE table that is pretty spot on for your combination.
Problem is, I don't know what units/how the stock LS1 table is formatted - you could calculate a normal VE table then scale the units to the same range as the stock LS1 VE table - but this may or may not work. Until we can figure out how the stock VE table is incorporated into SD fueling calculations...
That or you could simply start with the stock table, throw in a wideband, and drive around. Bigger numbers = more fuel at each point, smaller numbers = less.
Chris
Problem is, I don't know what units/how the stock LS1 table is formatted - you could calculate a normal VE table then scale the units to the same range as the stock LS1 VE table - but this may or may not work. Until we can figure out how the stock VE table is incorporated into SD fueling calculations...
That or you could simply start with the stock table, throw in a wideband, and drive around. Bigger numbers = more fuel at each point, smaller numbers = less.
Chris
02-10-2003, 10:15 AM
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Re: MAFless/Speed density tuning questions within Sounds like a PITA <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
What does the stock computer do when the MAF dies for some reason?
It reverts to SD right?
I know I can tune for WOT but I dont know what the dangers are for Part throttle driveability...
thanks,
Chris
What does the stock computer do when the MAF dies for some reason?
It reverts to SD right?
I know I can tune for WOT but I dont know what the dangers are for Part throttle driveability...
thanks,
Chris
02-13-2003, 11:18 PM
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Re: MAFless/Speed density tuning questions within Please forgive me if my reasoning is off but I'm trying to learn. ChrisB's observations are very interesting but I am still puzzled. I believe that the "right" way to control an LS1 is with a MAF sensor. It is better to measure airflow than to estimate airflow. Speed-density and reliance on VE tables would be the way to go only if good MAF sensors were unavailable. I assume that the reason you want to remove the MAF is to reduce airflow restriction in the induction path. Since you currently have a stock MAF and "only" a 360 ci motor, why don't you simply install an 85 mm MAF? Modifying the MAF table is trivial compared to creating VE tables. Isn't it true that some NA LS1s with MAFs are producing more than 600 hp? And isn't the bottleneck the intake manifold rather than the MAF? Your plan seems like a lot of work with little potential for gain over the best that can be accomplished more easily with a MAF. I'm just wondering why you want to remove the MAF.
Thanks, Gary
<small>[ February 14, 2003, 12:09 AM: Message edited by: Gary Z ]</small>
Thanks, Gary
<small>[ February 14, 2003, 12:09 AM: Message edited by: Gary Z ]</small>
02-14-2003, 06:48 AM
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Re: MAFless/Speed density tuning questions within It does sound like a good idea. I love when I cold start my car and let it idle for like a minute or so. Then rev the engine. It revs up real fast. I love that. But as soon as the PCM goes into closed loop the throttle responds isn't as crisp. Now is that just the " cold start" program? Or is the PCM more or less running in speed density until it warms up and goes into closed loop? Even after I cold start my car then drive off it feels like an animal. Just curious.
Den
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02-14-2003, 07:17 AM
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Re: MAFless/Speed density tuning questions within </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 02BlackWS6:
<strong>Or is the PCM more or less running in speed density until it warms up and goes into closed loop? Even after I cold start my car then drive off it feels like an animal. Just curious.
Den </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The only time the car would be in speed density mode and rely on the VE tables would be a situation where the MAF was not present or functioning. My car is set up to run in open loop all the time, and never goes into closed loop. You're still using input from the MAF in open loop, just not feedback from the O2 sensors.
I think I've convinced myself to try the SLP 85mm MAF on my car, since it's supposed to be calibrated the same as the stock MAF. I believe my stock (de-screened) MAF may be a little bit of a restiction on my car at this point. The SLP MAF is inexpensive enough to give it a shot...
<strong>Or is the PCM more or less running in speed density until it warms up and goes into closed loop? Even after I cold start my car then drive off it feels like an animal. Just curious.
Den </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The only time the car would be in speed density mode and rely on the VE tables would be a situation where the MAF was not present or functioning. My car is set up to run in open loop all the time, and never goes into closed loop. You're still using input from the MAF in open loop, just not feedback from the O2 sensors.
I think I've convinced myself to try the SLP 85mm MAF on my car, since it's supposed to be calibrated the same as the stock MAF. I believe my stock (de-screened) MAF may be a little bit of a restiction on my car at this point. The SLP MAF is inexpensive enough to give it a shot...
02-14-2003, 08:27 AM
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Re: MAFless/Speed density tuning questions within Yes, speed-density uses the MAP (density) and
engine RPM (speed) and a VE mapping to determine
the airflow. That's how a lot of FI systems used
to be designed. The big thing about the MAF is,
you can dick around with intake, exhaust and
internals, and still get the right airflow
value everywhere while with SD every change has
at least the potential of throwing off your cal.
So the move to MAF has been a real blessing for
the low-end, bolt-on-per-paycheck enthusiast.
I got a SLP 85mm MAF used for like $80 or $85,
it was performance-neutral around town I feel
(this is a good thing IMO) and I have MAP drops
from ambient of under 0.5PSI at WOT 6KRPM with
that, a lid and a ported TB. That's got to be
pretty near good enough, >96% "intake efficiency" minimum.
engine RPM (speed) and a VE mapping to determine
the airflow. That's how a lot of FI systems used
to be designed. The big thing about the MAF is,
you can dick around with intake, exhaust and
internals, and still get the right airflow
value everywhere while with SD every change has
at least the potential of throwing off your cal.
So the move to MAF has been a real blessing for
the low-end, bolt-on-per-paycheck enthusiast.
I got a SLP 85mm MAF used for like $80 or $85,
it was performance-neutral around town I feel
(this is a good thing IMO) and I have MAP drops
from ambient of under 0.5PSI at WOT 6KRPM with
that, a lid and a ported TB. That's got to be
pretty near good enough, >96% "intake efficiency" minimum.
02-14-2003, 09:23 AM
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Re: MAFless/Speed density tuning questions within I agree that MAF is the way to go - no question - but if people still want to experiment with the SD fueling mode - more power to them!
02BlackWS6: GeorgeC nailed it - you are describe closed loop mode (with an additional enrichment for the low temperature - look at the desired AFR table for open loop). This is pretty common - most of the time the car will idle/feel better richer than stochiometric - but gas mileage/emissioms will not be as good.
Chris
02BlackWS6: GeorgeC nailed it - you are describe closed loop mode (with an additional enrichment for the low temperature - look at the desired AFR table for open loop). This is pretty common - most of the time the car will idle/feel better richer than stochiometric - but gas mileage/emissioms will not be as good.
Chris
02-14-2003, 10:06 AM
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Re: MAFless/Speed density tuning questions within Chris,
Your flexibility with our MAF system is excellent, you should have an easier time tuning for best drivibility and peak HP with our current MAF system.
However, if you need good advice on speed density tuning, I recommend that you log onto thirdgen.org and go to their chip burning forum. These guys are very good with speed density on their '90 to '94 cars.
Your flexibility with our MAF system is excellent, you should have an easier time tuning for best drivibility and peak HP with our current MAF system.
However, if you need good advice on speed density tuning, I recommend that you log onto thirdgen.org and go to their chip burning forum. These guys are very good with speed density on their '90 to '94 cars.
02-14-2003, 10:30 AM
#12
Re: MAFless/Speed density tuning questions within Well DFI/Motec/FAST all run in speed density and have much better ability to control the fueling and timing.I wonder if someone could develop a piggy back harness that hardwires a wideband into a stock pcm,then u could run ls1edit along with the wideband and get rid of the stock o2's and tune via a laptop?
The question I have is,would Edit correct constantly or be a fixed value?
JS
<small>[ February 14, 2003, 10:41 AM: Message edited by: JS ]</small>
The question I have is,would Edit correct constantly or be a fixed value?
JS
<small>[ February 14, 2003, 10:41 AM: Message edited by: JS ]</small>
02-14-2003, 10:31 AM
#13
Re: MAFless/Speed density tuning questions within </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Gary Z:
<strong> I'm just wondering why you want to remove the MAF.
Thanks, Gary </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Speed density is a very accurate method of determining the airflow through an engine. If the calibration is done properly, and the measuring equipment is accurate, then you will be able to get just as good, if not better, results than MAF sensors.
A second advantage of SD running is that there is no "flash-to-bang". With an MAF you have to 'wait' for the MAF to report the proper airflow before fueling is applied (unless you use some form of suedo SD / MAF tuning). In SD mode fueling is more synonymous with the actual charge entering the cylinder. This is no big deal for a street driven car but it can play an important role for cars that need maximum power / throttle response under sudden load changes (like launching for example).
A third advantage of SD running is no reversion effects. When you start going to custom intakes and MONSTER cams MAF sensors become unreliable and almost unstreetable for some applications.
A fourth advantage of running SD is having the ability to run whatever type of intake tract you choose. This can be a very important advantage for those with space confines or open intakes.
A fifth advantange is being able to tune the intake. Removing the MAF is like removing the CATs in the exhuast. Once gone, you are free to lengthen, shorten or widen the intake tract to better take advantage of intake pulses. There is a lot of horsepower to be made with a tuned intake tract.
Just my .02
<strong> I'm just wondering why you want to remove the MAF.
Thanks, Gary </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Speed density is a very accurate method of determining the airflow through an engine. If the calibration is done properly, and the measuring equipment is accurate, then you will be able to get just as good, if not better, results than MAF sensors.
A second advantage of SD running is that there is no "flash-to-bang". With an MAF you have to 'wait' for the MAF to report the proper airflow before fueling is applied (unless you use some form of suedo SD / MAF tuning). In SD mode fueling is more synonymous with the actual charge entering the cylinder. This is no big deal for a street driven car but it can play an important role for cars that need maximum power / throttle response under sudden load changes (like launching for example).
A third advantage of SD running is no reversion effects. When you start going to custom intakes and MONSTER cams MAF sensors become unreliable and almost unstreetable for some applications.
A fourth advantage of running SD is having the ability to run whatever type of intake tract you choose. This can be a very important advantage for those with space confines or open intakes.
A fifth advantange is being able to tune the intake. Removing the MAF is like removing the CATs in the exhuast. Once gone, you are free to lengthen, shorten or widen the intake tract to better take advantage of intake pulses. There is a lot of horsepower to be made with a tuned intake tract.
Just my .02
02-14-2003, 11:04 AM
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Re: MAFless/Speed density tuning questions within </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JS:
<strong> Well DFI/Motec/FAST all run in speed density and have much better ability to control the fueling and timing.I wonder if someone could develop a piggy back harness that hardwires a wideband into a stock pcm,then u could run ls1edit along with the wideband and get rid of the stock o2's and tune via a laptop?"</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Not really a SD vs. MAF comparison though (or at least only those two factors) - with the other systems mentioned you have real time editing, integrated wideband options, and multi-bar MAP sensors. Things you aren't likely to have on a LS1 stock computer.
that said you will still probably have better drivability, etc. with a properly tuned stock pcm than with and of the aftermarket computers - after all, that is what the stock computer was designed for (Drivability/emissions on one specific platform) vs. having to be a general usage device - plus GM has a bit more engineering muscle.
The aftermarket systems are only really an advantage if you want to go FI - then the lack of a multi-bar boost sensor and integrated wideband is a large issue.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Speed density is a very accurate method of determining the airflow through an engine. If the calibration is done properly, and the measuring equipment is accurate, then you will be able to get just as good, if not better, results than MAF sensors.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
I disagree with that! SD is not a bad tuning method, and definiately works - but I don't believe it can be as accurate/precise as MAF tuning. In a SD system you basically look at your manifold pressure, RPM, and used a stored VE value for each pair of points to determine what you *think* airflow is (which is influenced by *many* factors). In a MAF system you don't worry about those - you just simply measure airflow and take it from there. MAF sensors, when properly calibrated/setup, and VERY accurate/precise. To me this just seems like a more elegant approach - you *know* exactly how much air is coming in, period.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A second advantage of SD running is that there is no "flash-to-bang". With an MAF you have to 'wait' for the MAF to report the proper airflow before fueling is applied (unless you use some form of suedo SD / MAF tuning). In SD mode fueling is more synonymous with the actual charge entering the cylinder. This is no big deal for a street driven car but it can play an important role for cars that need maximum power / throttle response under sudden load changes (like launching for example).</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
The MAF is fast enough that it can do this - and remember, the MAF is located "upstream" from the cylinders, so it meters changes in flow before it actually "gets" to the cylinders - not a tremendous lag, but then the response time on the MAF is *very* low also. On a SD system what you referr to is not metered directly with MAP readings - rather there is another table called "accelerator pump shot" or something to that effect. yes, it could become an issue on a 2000+HP race car that only went at idle and WOT, but for our situation I would submit that the lag time, etc. isn't a relevant issue.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A third advantage of SD running is no reversion effects. When you start going to custom intakes and MONSTER cams MAF sensors become unreliable and almost unstreetable for some applications.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
You would have to go very large indeed to get reversion issues out past the TB - again, while it could be an issue, we are talking pro-stock level cams here - not anyting that *anyone* is running (even Fireball <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> ). And you can very easily cause a MAF vehicle to approximate SD operation for a given MAF range (just find the airflow range for idle, set the car in PE mode, and make the MAF flow constant for that frequency input range - not a true SD mode, but it will be even less sensitive to reversion, etc)
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A fourth advantage of running SD is having the ability to run whatever type of intake tract you choose. This can be a very important advantage for those with space confines or open intakes.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Definitely - this and cost are probably the primary reason SD systems are still popular in the aftermarket.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A fifth advantange is being able to tune the intake. Removing the MAF is like removing the CATs in the exhuast. Once gone, you are free to lengthen, shorten or widen the intake tract to better take advantage of intake pulses. There is a lot of horsepower to be made with a tuned intake tract.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Not so much in the intake path as in the intake manifold itself. I don't think there is that much, if any power in intake path tuning for the kind of setups being run here - and even on wilder setups the pre-tb path isn't that important for any kind of semi-streetable ls1 setup. But given those qualifications I agree with you on this point, though I think it is the same as (4) above.
Chris Bennight
<strong> Well DFI/Motec/FAST all run in speed density and have much better ability to control the fueling and timing.I wonder if someone could develop a piggy back harness that hardwires a wideband into a stock pcm,then u could run ls1edit along with the wideband and get rid of the stock o2's and tune via a laptop?"</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Not really a SD vs. MAF comparison though (or at least only those two factors) - with the other systems mentioned you have real time editing, integrated wideband options, and multi-bar MAP sensors. Things you aren't likely to have on a LS1 stock computer.
that said you will still probably have better drivability, etc. with a properly tuned stock pcm than with and of the aftermarket computers - after all, that is what the stock computer was designed for (Drivability/emissions on one specific platform) vs. having to be a general usage device - plus GM has a bit more engineering muscle.
The aftermarket systems are only really an advantage if you want to go FI - then the lack of a multi-bar boost sensor and integrated wideband is a large issue.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Speed density is a very accurate method of determining the airflow through an engine. If the calibration is done properly, and the measuring equipment is accurate, then you will be able to get just as good, if not better, results than MAF sensors.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
I disagree with that! SD is not a bad tuning method, and definiately works - but I don't believe it can be as accurate/precise as MAF tuning. In a SD system you basically look at your manifold pressure, RPM, and used a stored VE value for each pair of points to determine what you *think* airflow is (which is influenced by *many* factors). In a MAF system you don't worry about those - you just simply measure airflow and take it from there. MAF sensors, when properly calibrated/setup, and VERY accurate/precise. To me this just seems like a more elegant approach - you *know* exactly how much air is coming in, period.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A second advantage of SD running is that there is no "flash-to-bang". With an MAF you have to 'wait' for the MAF to report the proper airflow before fueling is applied (unless you use some form of suedo SD / MAF tuning). In SD mode fueling is more synonymous with the actual charge entering the cylinder. This is no big deal for a street driven car but it can play an important role for cars that need maximum power / throttle response under sudden load changes (like launching for example).</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
The MAF is fast enough that it can do this - and remember, the MAF is located "upstream" from the cylinders, so it meters changes in flow before it actually "gets" to the cylinders - not a tremendous lag, but then the response time on the MAF is *very* low also. On a SD system what you referr to is not metered directly with MAP readings - rather there is another table called "accelerator pump shot" or something to that effect. yes, it could become an issue on a 2000+HP race car that only went at idle and WOT, but for our situation I would submit that the lag time, etc. isn't a relevant issue.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A third advantage of SD running is no reversion effects. When you start going to custom intakes and MONSTER cams MAF sensors become unreliable and almost unstreetable for some applications.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
You would have to go very large indeed to get reversion issues out past the TB - again, while it could be an issue, we are talking pro-stock level cams here - not anyting that *anyone* is running (even Fireball <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> ). And you can very easily cause a MAF vehicle to approximate SD operation for a given MAF range (just find the airflow range for idle, set the car in PE mode, and make the MAF flow constant for that frequency input range - not a true SD mode, but it will be even less sensitive to reversion, etc)
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A fourth advantage of running SD is having the ability to run whatever type of intake tract you choose. This can be a very important advantage for those with space confines or open intakes.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Definitely - this and cost are probably the primary reason SD systems are still popular in the aftermarket.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
A fifth advantange is being able to tune the intake. Removing the MAF is like removing the CATs in the exhuast. Once gone, you are free to lengthen, shorten or widen the intake tract to better take advantage of intake pulses. There is a lot of horsepower to be made with a tuned intake tract.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Not so much in the intake path as in the intake manifold itself. I don't think there is that much, if any power in intake path tuning for the kind of setups being run here - and even on wilder setups the pre-tb path isn't that important for any kind of semi-streetable ls1 setup. But given those qualifications I agree with you on this point, though I think it is the same as (4) above.
Chris Bennight
02-14-2003, 01:36 PM
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Re: MAFless/Speed density tuning questions within Wow! Just when I’m starting to feel a bit smug about what I’ve learned, you guys blow me away. Thanks very much for the information.
02-14-2003, 03:39 PM
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Re: MAFless/Speed density tuning questions within ChrisB,
Very well stated. This is a debate that rages on over on thirdgen.org. Anyway, with the improved MAFs we have today along with the OBDII PCMs, I think that MAF is the way to go when you consider everything.
This does not mean that SD is poor, in fact, SD is a good way to go also. On the thirdgen cars (I have an '87 L98 Camaro), the MAF sensors are not as robust as I have on my '99 LS1 car. One option that I have with my '99 car are 85mm MAFs. I do not have this option with my '87 car.
The debate goes on.
Very well stated. This is a debate that rages on over on thirdgen.org. Anyway, with the improved MAFs we have today along with the OBDII PCMs, I think that MAF is the way to go when you consider everything.
This does not mean that SD is poor, in fact, SD is a good way to go also. On the thirdgen cars (I have an '87 L98 Camaro), the MAF sensors are not as robust as I have on my '99 LS1 car. One option that I have with my '99 car are 85mm MAFs. I do not have this option with my '87 car.
The debate goes on.
02-14-2003, 08:20 PM
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Re: MAFless/Speed density tuning questions within I was just curious about it. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
how much is the SLP 85mm MAF with "stock" calibration? (Is that with screen or without?
Cheers,
Chris
how much is the SLP 85mm MAF with "stock" calibration? (Is that with screen or without?
Cheers,
Chris
02-15-2003, 12:05 AM
#19
Re: MAFless/Speed density tuning questions within Chris suppose u could tap into the factory PCM and have it correct (fuel/tming)on the fly like I'm talking about?Then piggy back a harness to run a wideband on the fly to...
If u could do this first,and make it resonable in price u would have a great setup.
I dissagree with u on one point,Chris..
My DFI controlled LT1 had soo much better ability to cold start,warm start and idle better than any maf setup I've had since.Throttle response was better too.
Do u think its poss to tap into the factory harness/pcm to do what I've thought up?
JS
If u could do this first,and make it resonable in price u would have a great setup.
I dissagree with u on one point,Chris..
My DFI controlled LT1 had soo much better ability to cold start,warm start and idle better than any maf setup I've had since.Throttle response was better too.
Do u think its poss to tap into the factory harness/pcm to do what I've thought up?
JS
02-15-2003, 01:31 AM
#20
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Re: MAFless/Speed density tuning questions within JS,
Do you guys sell SVO 42# injectors at your shop?
Den
P.S.
When I install my blower do you think the Vig.2800 would be too small? I might be able to get a new one for $600.
Den
<small>[ February 15, 2003, 01:33 AM: Message edited by: 02BlackWS6 ]</small>
Do you guys sell SVO 42# injectors at your shop?
Den
P.S.
When I install my blower do you think the Vig.2800 would be too small? I might be able to get a new one for $600.
Den
<small>[ February 15, 2003, 01:33 AM: Message edited by: 02BlackWS6 ]</small>