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just dont get it

If the air/fuel ratio becomes excessively rich, it can drown out the engine with fuel and actually put the "fire" out - especially under idle and low speed conditions.

A high flow injector has a larger "hole" than a smaller one. So more fuel flows through it per pulse. If you increase the size of the injector, but do nothing to change the programming to shorten the injector "on" time, the engine will run too rich. So to maintain the optimum A/F ratio that makes the car run well at other than wide open throttle, the computer has to shorten the duration of the injector pulse.

To change the computer programming in your case required changing the chip. If you don't have a wideband O2 gauge, you probably should buy one to make sure that your non-stock programming is working well.
 
michbc3 said:
If the air/fuel ratio becomes excessively rich, it can drown out the engine with fuel and actually put the "fire" out - especially under idle and low speed conditions.

A high flow injector has a larger "hole" than a smaller one. So more fuel flows through it per pulse. If you increase the size of the injector, but do nothing to change the programming to shorten the injector "on" time, the engine will run too rich. So to maintain the optimum A/F ratio that makes the car run well at other than wide open throttle, the computer has to shorten the duration of the injector pulse.

To change the computer programming in your case required changing the chip. If you don't have a wideband O2 gauge, you probably should buy one to make sure that your non-stock programming is working well.
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are you talking about a powerlogger? if so julio said to get one so he can dial it in
 
robert lee said:
are you talking about a powerlogger? if so julio said to get one so he can dial it in
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No, he's talking about a more accurate O2 sensor. A power logger is a data logging tool you install as a piggyback on your ECM and monitor or log data in real time.At this point the WB would just be a spectator and maybe too much information. Besides, without using a PL and an updated Scanmaster he wont be able to view real time WB O2's unless he installed a Brand specific WB gauge.

It's my opinion that at this point Robert can do well with just his narroband O2 and TT 5.7 chip. His adjustability is limited to PE mode anyways and overall fueling and the 1-2 gears.

Eric's got a really,really good handle on the use of the Motoron 60# in his chips.So I wouldn't be the least bit concerned with the chip's programming during normal open/closed loop operation.
 
WS6 said:
No, he's talking about a more accurate O2 sensor. A power logger is a data logging tool you install as a piggyback on your ECM and monitor or log data in real time.At this point the WB would just be a spectator and maybe too much information. Besides, without using a PL and an updated Scanmaster he wont be able to view real time WB O2's unless he installed a Brand specific WB gauge.

It's my opinion that at this point Robert can do well with just his narroband O2 and TT 5.7 chip. His adjustability is limited to PE mode anyways and overall fueling and the 1-2 gears.

Eric's got a really,really good handle on the use of the Motoron 60# in his chips.So I wouldn't be the least bit concerned with the chip's programming during normal open/closed loop operation.
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okay guys , what if anything do i need to buy, i have read this about 20 times and i think i understand, but not sure, since i am a rookie, give it to me in laymans terms, thanks for your help, you guys are smart as hell ,yall could do this for a living. :yes:
 
Since I am using the Motoron 60# and match flow chip from Eric along with Alky from Julio.

I have the boost adjusted at 18lbs with Alky and zero knock. Alky dash gain control is set at the 4 mark. For the street.

They told me if I wanted to go to the strip I can turn my boost up to 20 or so lbs. And also turn the Alky knob a little higher. As long as I have no knock.
 
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My car isn't as modded as the majority of you, but I've always wondered, why do you guys stay with the stock ECM. You're trying pump in new technology from every basis into the stock ECM that your working way past it's limits. Why not just switch to a stand alone? I know you have to rewire the engine harness of the car, which honestly shouldn't be too difficult for a car of our generation. However you're going to come out at about the same cost. but a much better standing for tuning and control capabilities.

You run a chip for high impedance injectors, alky, wideband reading and compensation, egts, etc. You might as well spend the money and do it right with a system set up for it instead of retrofitting a 20 year old computer. Just my opinion, but once you're at the point of switching the ECM to high impedance injectors, it's time to switch to an aftermarket computer.
 
I guess I am saying that Robert has everything he needs. Scanamster, chip and injector kit and new turbo!


But Jared, I partially agree with you.There is point, performance wise and tuning wise that the we have exceeded the stock ECM's ability to control the tune and for us to control the ECM.

But by in large the stock ECM,I believe, has more than enough speed and memory to allow the user to control minor fueling and timing changes. And more so even advanced fueling like WB targetting and even speed density tuning vs. mass air flow.

But you're right, at a point the stock ECM isn't fast enough to let's say track 6 EGT probes or 2 daisy chained WB O2'snd trim fuel and timing on it's own.So if you're looking to keep your $22K stage II together on a 10.2 pass then a standalone is the best choice.But for us guys going 11.xx-14.xx you just can't beat the cost effectiveness of the factory ECM and aftermarket chips. After all, either choice requires the mechanicals of turbos,injectors,MAF's,translators, WB's etc.So you don't save there.

I don't know what a new stand alone costs I see used ones going for $800-$1400 and some of those are bank to bank systems.Add a couple dyno tune sessions and you're easily at $2000.

I guess I'm saying one would have to be pretty serious to take that leap.Besides plenty of really fast guys are still doing it on stock ECM down into the 9 second range.
Jason and I have talked about this very thing and I agree it seems like we are approaching the limits of the stock stuff, but until I see allot of price decrease in a stand alone I'm not doing it. Because I'm getting the job done on 20 year old technology.
 
the tta is running great, but the iac still bottoms out when its warmed up in park , im going to adjust one more time, if it dont work i will try a new one. i am going to nc this morning to get the 1988 gta i bought, the seller says that i will change my mind about parting it out when i see it, i checked and it looks like there was 1,957 made like this one
 
Rich's info is great.

Our 20 year old chit is plenty fast enough... I'm running Eric's SD chip and love it!
 
Quiky One said:
It isn't plenty fast enough. It is doable though.

Please, don't spout off info about SD tuning until you run your car down a track.
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basically what im getting from all this is me, and a lot of other people are spending alot of money , time and effort to get this cars 1-2 seconds faster than stock, but its still fun :yes:
 
Quiky One said:
It isn't plenty fast enough. It is doable though.

Please, don't spout off info about SD tuning until you run your car down a track.
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The stock ECM has all the processing power necessary. The stock ECM can make corrections 160 times per second if you want it to but that's much too fast for wideband correction.
 
robert lee said:
basically what im getting from all this is me, and a lot of other people are spending alot of money , time and effort to get this cars 1-2 seconds faster than stock, but its still fun :yes:
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A lot of money is relative. You'd be spending two or three times more money purchasing, installing and programming a stand-alone system. For what you're doing, the GM computer and a chip can handle it as long as you are using a high impedance injector. Most of the larger injectors (beyond 60 lb) are low impedance and require more drive current than an unmodified GM computer can deliver. Even so, some guys have modified the GM computer by changing the output drivers to push out more current.
 
michbc3 said:
A lot of money is relative. You'd be spending two or three times more money purchasing, installing and programming a stand-alone system. For what you're doing, the GM computer and a chip can handle it as long as you are using a high impedance injector. Most of the larger injectors (beyond 60 lb) are low impedance and require more drive current than an unmodified GM computer can deliver. Even so, some guys have modified the GM computer by changing the output drivers to push out more current.
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as long as it will run in the 12 sec range and stay together im happy, i drove it yesterday and the guy beside me almost slammed into the back of a car looking at it, funny as hell :jaw:
 
robert lee said:
as long as it will run in the 12 sec range and stay together im happy, i drove it yesterday and the guy beside me almost slammed into the back of a car looking at it, funny as hell :jaw:
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You've got the basic "formula" (chip, larger injectors, larger turbo and alcohol) that will get you in the 12s. 12s are no problem as long as it doesn't run too lean, the boost pressure is reasonable, the timing is not too aggressive and the fuel has enough octane (or alcohol injection). Yes, staying together is important.
 
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