48 lb injectors Tweecer tunner help

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Devon

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Hello
I purchased 48 lb Accel injectors new from sho bros a few years back.
and a tweecer. Finally I Installed them yesterday.
did some reading about high and low slope. and did 85 high over 47 low to start with
and the car started and Idled, but of course it did not run right other wise.

the car is a 3.2 swap mtx with sho shop stage 2 cams, sho shop headers, BBB, 77mm Pro M MAF, Shonut FPR (set to stock presure 39-40).
and I have a Vortech S-trim I have been planning on putting in, I don't need the car to get to work so I figured I would try super charging it now.

I also have a Mark 8 MAF but I think I might max it out when I supercharge it, I don't know if I should get a lighting 80mm or if I really need a 90mm
won't it get hardet to tune for idle with a 90mm?

I thought it would be a good idea to start learning how to use my tweecer by just changing the injectors first.

on of my o2 sensors looks lazy on the CalCon screen so I picked up a new one and will have it changed soon.

some thing I do not have is a wide band O2 I am not sure what is the best set up to go with in this area.

I have already done a bunch of reading on hear, and in other places about using my tweecer but I have a lot of missing information in my brain still about this subject.

an example is Break points; in cal edit I see the word break points used in more than one place and I me not sure how to change them or wich one(s)
to change.

I got the battery offsets changed as described. in one of the posts
0.75 12v 0.50 14v 0.35 16v

I did not notice a change in performance with this change though.

I know that with stock slop settings the car might fire but it does not run.

basically I do not know what I am doing hear as I have just begun the learning process of tuning with a tweecer.

I would like to make a good tune and then make a chip from moats.
and as I said I don't know what O2 set up to go with so i have not purchased the licence to the software yet because of that.

any help on choice of O2 set up to go with and tuning help would be greatly appreciated hear. thanks!
 
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yamahaSHO

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If you don't plan on big boost, you'll be fine with a 80mm Lightning MAF. I am maxing out my 80mm Lightning MAF at 16 PSI. I have a 90mm on the shelf.

Give these numbers a shot (assuming they are the gray/silver injectors) and see what it does. This should only be a good starting point!

Injector Offset vs. Battery Voltage:

Voltage -- Adder

15.9375 -- 0.5000
14.0000 -- 0.5938
12.0000 -- 0.8125
10.0000 -- 1.1563
8.0000 -- 1.5938
6.0000 -- 2.4375
0.0000 -- 2.7813
0.0000 -- 2.7813
0.0000 -- 2.7813
0.0000 -- 2.7813
0.0000 -- 2.7813
0.0000 -- 2.7813

Injector Breakpoint:
3.9998 - Across the board.


High Slope / Low Slope:

HS - 48.0001
LS - 57.0004


Cranking Pulsewidth vs ECT:

DegF -- Pulsewidth

65534.00 -- 0.0044688000
254.00 -- 0.0044688000
230.00 -- 0.0060496000
122.00 -- 0.0199272000
68.00 -- 0.0717288000
40.00 -- 0.0956232000
0.00 -- 0.1992264000
-30.00 -- 0.2829024000
-65536.00 -- 0.2829024000


Make sure you have the correct OEM MAF curve for your exact MAF.

Some day, I'll work more resolution into the Injector Offset vs. Battery Voltage. If you're really looking to tune the injectors any further than slopes and BP, you'll want Binary Editor to be able to log voltage.

As far as Wideband O2's... I have a PLX setup in two cars (used a previous PLX on the SHO prior) and they are great. Great reliability compared to some of the other setups I've helped people tune with.
 
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Devon

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my TPS Voltage only reads 3.51 is this a problem? considering the Injector Breakpoint should be 3.9998 - Across the boar like you said?

Injector Breakpoint:
3.9998 - Across the board.

by the way thanks for replying so quickly, the car is running a lot better already!
 

yamahaSHO

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Breakpoint has nothing to do with the TPS. It is a function on HS/LS crossover.
 

Devon

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i have to start my car on an old tune, because now with all these changes the car will not start again when I shut it off. but I can start it on an old tune and switch it and it runs better so I know that the new tune you gave me with just these changes works better.

do you know what might be causing this?
 

Devon

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it ran really good on the first two changes that you gave me.
these helped right away and the car pulled nice and strong on wot.
no wot light on the calcon though.
since I am not boosted its safe to go wot right?


High Slope / Low Slope:

HS - 48.0001
LS - 57.0004


Cranking Pulsewidth vs ECT:

DegF -- Pulsewidth

65534.00 -- 0.0044688000
254.00 -- 0.0044688000
230.00 -- 0.0060496000
122.00 -- 0.0199272000
68.00 -- 0.0717288000
40.00 -- 0.0956232000
0.00 -- 0.1992264000
-30.00 -- 0.2829024000
-65536.00 -- 0.2829024000


but when I moved the Injector Offset vs. Battery Voltage:
it seemed like it was not pulling as hard but it could be that the engine was warmed up by the time I changed the Injector Offset vs. Battery Voltage:

the ECT was about 140 when it ran the strongest on the first two changes. maybe it was still commanding more fuel at that point?
 

yamahaSHO

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i have to start my car on an old tune, because now with all these changes the car will not start again when I shut it off. but I can start it on an old tune and switch it and it runs better so I know that the new tune you gave me with just these changes works better.

do you know what might be causing this?

You may have to increase cranking PW. This works with my car/injectors, but not all cars/injectors will react the same. I'd recommend increasing it 5% across the board. If the car is only having trouble starting when it is warm, you may focus your efforts between 122 - 254F.


it ran really good on the first two changes that you gave me.
these helped right away and the car pulled nice and strong on wot.
no wot light on the calcon though.
since I am not boosted its safe to go wot right?


High Slope / Low Slope:

HS - 48.0001
LS - 57.0004


Cranking Pulsewidth vs ECT:

DegF -- Pulsewidth

65534.00 -- 0.0044688000
254.00 -- 0.0044688000
230.00 -- 0.0060496000
122.00 -- 0.0199272000
68.00 -- 0.0717288000
40.00 -- 0.0956232000
0.00 -- 0.1992264000
-30.00 -- 0.2829024000
-65536.00 -- 0.2829024000


but when I moved the Injector Offset vs. Battery Voltage:
it seemed like it was not pulling as hard but it could be that the engine was warmed up by the time I changed the Injector Offset vs. Battery Voltage:

the ECT was about 140 when it ran the strongest on the first two changes. maybe it was still commanding more fuel at that point?


Be sure to clear the PCM when you make a significant write. The easiest way is to load an A9L strategy to the 4th position on the TwEECer, turn the ignition on, flip to the forth spot, listen for the fans to come on, then flip back to the spot you want to write to.

At this point, you'll have to start monitoring your logging to see what is going on. The stock O2 sensors are very useful when figuring out what is really happening. The Injector Offset vs Battery Offset and HS/LS work closely together (if you drastically change one, you'll likely have to adjust the other). Injectors will react different at different voltages. When the voltage is lowered, it will require and "adder" to compensate for the low voltage. Ideally, you set the HS/LS and work the offset. I've gotten that offset pretty close for those injectors.

But don't forget, you'll want to clear the PCM. If you make the changes with learned trims, it'll have to fight against them for awhile which makes it more difficult to find the degree of change that the PCM is really trying to correct for (Lambse = Commanded AFR at the moment - KAMRF = Fuel trim based off commanded values in your fuel table vs what the O2's are seeing). If you know your table is supposed to be commanding 14.64 and the Lambse is showing 18.xx, you it is commanding a learner mixture to immediately correct for a rich condition. Eventually you'll see these settle and the KAMRF will start to show long term trims (1 = no correction / >1 correcting for lean condition / <1 = correcting for a rich condition). I aim for a 5% correction in either direction as you will NEVER get it to just sit at 1 over time.

As far as the WOT light in CalCon... I'm not sure that even works correctly. The reason why people are moving to Binary Editor is that more features are unlocked. My biggest drive to change over was being able to log voltage, which has never worked with CalCon. This is all in reference to the SHO specifically.
 
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Devon

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I multiplied the numbers for 122 - 254F. by 1.05 and re-entered them and saved it to the tweecer, it still did not start so I switched it to another tune to start it again then moved over to the 5% increased tune with the switch wile the car was running and logged it running and I could not tell any thing diffrent by the numbers on the log file, I don't know if I would find any thing I was just trying to learn. the tack on my dash died and the car stumbled and died so I switched the key off and back on then poped it in gear because I was still rolling, and it seemed to run fine still then the tack came back just before finishing a lap around the block.
 

yamahaSHO

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If you start the car and switch the tune quickly, you will not have any correction going on as you will be in OL. When the car settles down, you will enter CL. If, while cranking, you step on the throttle (WOT), does the car try to start? If so, you may already be too rich and need to back it off. This will be something you'll have to play with. Without being there, I can say you'll have to figure out if it's getting too much fuel or not enough when trying to start a warm engine.

You won't see anything in the logs for cranking or even adjusting/switching cranking PW. The car will be in OL and the O2's will likely not be warm enough to give good readings. If the car is trully running better, but just having issues starting when warm, you'll just need to address that area.

If it is still having issues on a hot start and you think it's not getting fuel, keep increasing the cranking PW table. I generally like to adjust the entire table by the same percentage unless there is obvious corrections needed in just one area of the table.
 
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Devon

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it is 1:30 am over here I got to go to bed for now but I will be back at it tomorrow.

I have been fiddling with this car for two days and with the numbers you gave me my car runs a whole lot better after about two minutes, this is a big deal for me and I truly appreciate your help.
 

Devon

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both before and after the 5% increase if the car sits for a wile 10-15 minutes it will start.
but if I just turn it off to try re-starting it, then it will not start even with the petal floored.
so maybe extra fuel is evaporating from the cylinders that have the valves open after some time then it is able to fire on those cylinders and start running?

but needs time to dry out after shutting the engine down?
 

Devon

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other wise switching to an old tune gets it started even after it was just turned off and then I run on the new tune, that it will not start from with out sitting for a wile.
 

yamahaSHO

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For testing, trying increasing the original numbers I gave you (hot range or entire table), by 25%. If no change, try 50%. It sounds like it's not getting enough fuel to me.

I'll check back in tomorrow sometime. Busy day, so I probably won't have anything for you until later in the day.
 

Devon

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I just multiplied the original numbers for 122 - 254F. by 1.50 this time and entered them,
saved them and then tried to start the car at this point the car had been sitting for 15 minutes and did not start, so I switched to the old tune started it switched to the new 50% increased tune wile running then shut it off, to try to restart it and it would not start with petal to the floor or not.

I have been trying to retrace my steps as to what things I changed first and why this is now happening.

erlier I try changing the break points back to what they were, this did not help it still did not start, it would also run if i started it from an old tune as I have been doing.
I did return the break points back to what you told me to put them att exept it changes my numbers to 3.9996 instead of 3.9998.
 

92sho16

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I just multiplied the original numbers for 122 - 254F. by 1.50 this time and entered them,
saved them and then tried to start the car at this point the car had been sitting for 15 minutes and did not start, so I switched to the old tune started it switched to the new 50% increased tune wile running then shut it off, to try to restart it and it would not start with petal to the floor or not.

I have been trying to retrace my steps as to what things I changed first and why this is now happening.

erlier I try changing the break points back to what they were, this did not help it still did not start, it would also run if i started it from an old tune as I have been doing.
I did return the break points back to what you told me to put them att exept it changes my numbers to 3.9996 instead of 3.9998.


The breakpoint does have anything to do with cranking the motor over. The breakpoint is the point when the computer starts using the high slope. I just tried loading up my tune in BE but i am having issues so i cant give you exact numbers but i decreased my cranking pw to get the car to start easier.
 

Devon

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I just purchased a licence for BE and EA, and I am thinking about getting the DM200 from PLX and a WB O2 sensor module for it,

my personal taste is to try to have a clean discreet look to the car so it does not look like a high performance car, so no piller pod for me, I just think it hurts negotiations if I ever get pulled over;)

so I want to put it in the mirror like this guy did...

http://www.tricktuners.com/more dm-200 008 (Large).jpg

I think it is cool idea and the gauge can handle multiple parameters,
like EGT and so on.

if you have any suggestions as to what would be the very top Items other than A/f that I might want to add to this I would like to hear about it.

I have decided to avoid the piggy back dual signal set up, were a WB O2 sends NB to the computer, and WB info to the controller.
from what I ready it seems cleaner to just add a bung and WB O2 separately.

I have decided also to get a Lighting MAF so that I don't have to keep going back and re-tuning all the time.

to day I took a 10 mile trip to pick something up and logged the run there and back, I saw some hight numbers in the LAMBSE 1 & 2
it stayed in the 15-17 most of the time, and 14.5 when I let off the petal from cruising at 60mph.

but the KAMRF never moved more than 0.05 from 1.00

when cold it seems to have a lot more power than I remember it ever having, could just be me though, and it still lugs a bit and has trouble spots in some RPM ranges, but it seems to be at least 80% of the way tuned.

I still need to change the lazy NB O2 and try to solve the no starting problem.

as I guessed though it did start this morning of of the new tune, and I shut it back of right away to see if I could do it twice but not a chance,
so I switched to the old tune and started it and switched to the new tune again wile running and went to go run that 10 mile trip.
 

yamahaSHO

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The Cranking numbers I gave you were cut in half from stock. You generally reduce based off the injector size increase, however, you have also reduced the adder for the injectors based on battery voltage. If you haven't tried increasing the hot range by 25-50%, try that. If that doesn't work, double the numbers in the hot range that I gave you. Ideally this is what you would do (increasing cranking PW adder)... I didn't as my car still starts fine when warm.

The numbers I gave you are what I'm using with my car. I already have a blower and other extensive mods, so you'll have to adjust for your car. Accel doesn't publish their specs, so I started with setting the HS at the physical injector size, LS 15% higher and logged and worked with the Injector/Battery Offset until I could work on HS/LS/BP.
 
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Devon

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is there any thing else I need to change like "WOT Fuel Multiplier vs RPM" ?
should I change them all to "1"?
 

Devon

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battery voltage I have tried increasing the hot range by 50%,
at first I could not see a change, but then when I started it from another tune and switched it to this one with 50% increase it dies instantly.

If I turn off both calcon and caledit and then restart them, read my tune from the tweecer and then change one thing and rewrite to the tweecer it only changes that one thing? the reason I ask is because when I reopen Caledit it seems to reset the parameters, and I assumed that reading the tweecer would set them to what is on the tweecer and I can change things from there.
 
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yamahaSHO

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is there any thing else I need to change like "WOT Fuel Multiplier vs RPM" ?
should I change them all to "1"?

Sure, but you're still addressing a different issue.

battery voltage I haven't tried increasing the hot range by 50%,
at first I could not see a change, but then when I started it from another tune and switched it to this one with 50% increase it dies instantly.

If I turn off both calcon and caledit and then restart them, read my tune from the tweecer and then change one thing and rewrite to the tweecer it only changes that one thing? the reason I ask is because when I reopen Caledit it seems to reset the parameters, and I assumed that reading the tweecer would set them to what is on the tweecer and I can change things from there.

The cranking PW should not effect anything once the engine is running. Ensure nothing has changed.

If you read from the TwEECer, it'll display what's currently on that selection. If you want to open a tune without reading, you need to save it to the laptop.
 

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