My truck has a fuel pressure regulator on the rail. It takes a lot of guesswork out of injector tuning.
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My truck has a fuel pressure regulator on the rail. It takes a lot of guesswork out of injector tuning.
It seems to me that F-body and Y-body are the only vehicles without one, everyone else has one.Quote:
Originally Posted by redhardsupra
If installing one, you'll also need to run a return line.
Quote:
Originally Posted by redhardsupra
Got any ideas on how to calculate a correction?
Well I did some more tweeking last night. Seems for my application 60lb mototron inj. like a little more offset at idle and small throttle opening. This gets rid of any miss and gives a decent BEN. The other points seem pretty close using the stock setting. When i increase all the points in the same ratio as stock, the car runs more rich and is sluggish. I need to fine tune some more. This indicates that the mototron inj are pretty fast for a big inj. They don't work well with the stock offset at very small pulse widths. I would still like to see the correct numbers for these inj. I did notice that when I increased all the cells, the AFR ratio was extremely stable - but rich.
And yeh, maybe a vacuum ref. regulator may make tuning these big inj. a bit easier. (Already have onewaiting to go on)
JfPilla
Can you share your SVO 30 table values?
Im still interested in seeing if i can get the voltage variations matched up better.
Sure, but it's not really ready.Quote:
Originally Posted by Flyer
Quick note before everyone goes off and ends up getting frustrated with the tuning of this table...
The injector data that I've seen for various injectors(manufactures, et) follows a similar curve. With that being said, this table shouldn't vary much from the stock table across the board. (Hint, when you do a % compare in EFILive on the table compared to stock your graph should look near flat IMO)
If you tuned your VE table and then try to tune this table, forget about it. Your probably done. You've probably made life for youself exponential more difficult. Same goes for any other table that affects fueling. Start with the stock knowns.
Keep it simple, the change shouldn't need to be drastic. (see my table above) Delco put it best in his post. Don't get wrapped up chasing your tail with another new table or the hype around the table. KISS
Example: Here's how it worked for me... I knew the ZO6 MAF table was correct (stock - after all GM spent massive $$$ to nail down the MAF flow characteristics in a C5), I knew the IFR table was correct (again - the math for stock injectors confirmed this and actual injector flow #'s for others confirm math). So, why was what I was commanding in PE not matching what I was seeing on the WB??? Partially, VE I'm sure. How, the characteristics of the injector are different also. Thus my quest began. Thanks to Chris B for the extrapolation math and the real data from a ford vehicle, born was a new offset table. Is it 100% accurate? Don't bet you life in it. Is it more accurate then stock... hell yeah, I peronally believe it to be based on the results... well, lets just say, what I command in PE is what I GET out through the tailpipes (Wideband) and always repeatable. At this point, I didn't even TOUCH the PE table, my WOT ltrims are 0 and my ltrims all together ranges from -8(very few) to +3 .
Either this worked out way to SIMPLE for me or I'm going crazy. I can't wait to VE tune. I don't think my VE table change will be drastic. What do you guys think? ;)
Anyone else do it this way? I'm not telling or suggesting to anyone that this is the way it should be done, merely sharing what worked for me based almost solely on given GM data and math over 2 years ago. Besides, I to lazy to guess at table # and flash the car hundreds of times when if all is right the math should work.
opps... I did say quick note... :bash:
:beer:
John,
The VE suggestion sounds good. I'll try it for sure.
Joe
Got any ideas on how to calculate a correction?
Would like to know also.
I created a custom PID some time ago that turns the LTFT values into a factor similar to BEN that I could use as a multiplier.
Could that work? Using a sort of multiplier against the current Voltage Offset table as sort of a error %?
Next file.
another one.
I'd try it. The biggest problem is logging volts. There's no way to control voltage and log them sufficiently. It looks like lots of extrapolating.Quote:
Originally Posted by Tordne
You will be combining all of the data for each map range and condensing it into one cell so there could be some error as your BEN is probably not 1 across the board. But it will give you an idea. One thing I looked at was the difference between the BEN factors between 13.5V and 14V for the same map values. Not how far the BEN was from 1.00. Only the difference. I think this is useful and got my BENs a lot closer.Quote:
Originally Posted by Tordne
Initially i used the maf and scaled the offset table so I had similar BEN values that i had with my stock injectors. I had to increase mostly around idle and not much at WOT.
Quote:
Originally Posted by hpcubed
Now that's a good idea...
It looks like you got your wish. The attached was done with the MAF so it's not accurate. I was interested in seeing the values it would produce. It should be done in SD. Any thoughts on what comes first?Quote:
Originally Posted by TAQuickness
-VE's back to stock.
-IOS adjusted.
-VE's
Those look pretty good already just need a little tweeking. I would adjust the IO's with the maf in open loop, then go to speed density and adjust the VE's. Don't really need to put the VE's back to stock.Quote:
Originally Posted by jfpilla
One question is how accurate is the stock offset table for the stock injectors. Assuming that it is very accurate, I think the way to do it would be:
1. Log BENs with maf in open loop using stock inj. If you have old files saved with this data you could use that.
2. Log BENs with maf in open loop using new inj.
3. Adjust inj. offset so that new BENS match old BENS. Obviously everything is not going to match perfectly. This effectively divides out the error in the maf.
4. Go to speed density and start the tuning process.
1. Log BENs with maf in open loop using stock inj. If you have old files saved with this data you could use that.Quote:
Originally Posted by hpcubed
>>>>That's out.
2. Log BENs with maf in open loop using new inj.
3. Adjust inj. offset so that new BENS match old BENS. Obviously everything is not going to match perfectly. This effectively divides out the error in the maf.
4. Go to speed density and start the tuning process.
>>>>I don't get the point of logging in open loop then tuning in SD?
I've established an offset table using ltft's vs volts and manvac and the stock VE table. You mentioned using Ben's so I tried it to see what kind of values would be returned. The results seem accurate but whenever the AFR changes enough it's obvious that trims affect these results making the results look decent since the AFR is being maintained by trims. It looks as if there are two ways to do this. 1) Set up the offset table by ltft's. This is very tedious. 2) Go into mafless mode and use BEN's.
What I don't know is if the VE table should be stock when doing offsets. VE's should be done with correct IFR's. If the IOS's are wrong then the IFR's are wrong. It sounds like I'm going around in circles and that's how I feel. Any opinions on my thinking are encouraged since I'm a little lost as to what to go at first. I guess I can do the offsets using BEN with a stock VE table in SD and see what I get. It would seem that if the offsets come into line then the VE table should also be close. I'd better save my current file since the car is running great with it.
1. What you suggest should work. But I would rather use a wideband than trims so that is why I suggest using the BENs (and open loop).
2. My suggested steps utilized the stock inj and maf because we need a known to compare to. And by doing it the way I suggest, the error from the maf is divided out. Since you can't do this in your situation. So you have to either accept that what your maf is saying as a known or the VE table. I would think the maf is more correct right out of the box - so to speak.
3. You set up your table as you suggested either using BENS or trim. However the value in your table for 1 cell is condensed down from the values of trims from all rpms for a given map. If they are all the same value then bingo if they are all over the place you have to use some judgement.
I've already done it by trims. It will be nice to do it by BEN and have them match what I've done, closely.
Thanks for the input.
I just had another go with the voltage offset table - this time i just changed the cells to suit the situation. The issue is i have used the IAT correction tables in the custom operating system to get the afrs consistent in different IAT and it is almost there....however the problem is that idle is still not cooperating and its leaning out when the IAT is hot but its not consistent with IAT temps ie. at the end of a long drive it is lean idling even when the IAT temps are lower than 30min before when the IAT temps were higher.
I think the issue is lower battery voltage after the car is driven for a while. Early in the drive its nearer to 13.4V at idle most of the time but when driven and hot its closer to 13.0V at idle and sometimes lower especially when the idle is erratic. I think leaness at idle is causing the erratic idle - it seems to be the main thing that is different ......so to fix it or at least i will find out tommorrow - i have just added a little extra offset in the cells that are used at idle in the voltage offset table , in the 11.5, 12.0, 12.5, 13.0 V columns. I added 0.08 in the 13.0V and 0.10 in the others. This should effectively richen things up a bit when the car goes lean at the end of long drives at idle
As i said earlier when moving and voltage is up a little higher the afrs at the end of a long drive are well sorted its just at idle things arent quite good all the time.
Currently im logging a 45min trip to work and trimming the tune and then logging on the way home. It makes the trip fun :thankyou2: EFIlive.
Makes your breaks at work fun too... :cheers:Quote:
Originally Posted by Flyer
This worked for me.
Calc. IFR and use stock MAF table.
With MAF.
Set up a MAP to log LTFTs_MANVAC_BATVOLTS and adjust these ltfts using IOS table. The VE's have no affect so you can keep what you've done. You can stop here. I like my VE's tuned even though I run the MAF.
MAFLESS.
Either do the above step first or if you don't have your maf installed do an autotune or keep your VE's if already done. Only adjust VE's to the point that DYNAIR matches MAF logged values. This will account for any incorrect IOS numbers. Then log IOS using BEN_MANVAC_BATVOLTS and adjust IOS.
I'm really pleased that the only tables now not stock are ETC and Startup Friction Airflow Correction. Probably due to having a 90MM TB.
Its offtopic - but here is a music video of the trip i made for a bit of fun. Its on the outskirts of Sydney where much of it is still farmland. http://www.athleticstraining.com/carsnew/fasthawk.wmv
jfpilla - Somehow I lost my train of though in this thread... Need some help to make sure I'm on the right page again.
Adjustments to the IOS are based on the difference in LTFT's or BEN's from one voltage/man_vac range to the next (column to column). If we're thinking the same thing, this part makes sense to me.
What's loosing me is what to use as the starting point. seems we would need at least one column of known good IOS offsets to use as a control.
It does appear that it's easier if you start using the MAF to get a decent IOS table. The option without an MAF is to set VE's to the point that the MAFgms and DYNAIRgms are close. That will get the AFR to a point and the difference is made up by setting the IOS table. The Offset Ben Map will get you there.Quote:
Originally Posted by TAQuickness
My IAC DES., DYNAIR and MAF numbers fell right in line.
It was magical.:banana:
Flyer,Quote:
Originally Posted by Flyer
Cool video, looks familiar, where exacltly was it shot...?
Joe:beer:
Edit: We're sorry to hijack the thread, we're attention challenged... :wave:
Blue Mountains to M4 then through Penrith and out Castlereagh Rd to North Richmond and beyond about 10min. Its a nice simple drive. In the mornings its been 25deg C and in the afternoons its been hot 33 deg C. Good variation for logging. But in winter it will be cooler and quicker!
My log today was a success - it seemed to help. I logged voltage and created a chart with rpm and afr and it seemed to show a good change.
Its certainly better parking up my driveway now when its hot. So i think this table is a good thing.
As soon as it has any lean afrs up near 15.0 at all when idling - the idle quality deteriorates.
this might be of some help/interest
http://www.ls1tech.com/forums/showth...09#post4573309
Hi Joe, just sent an email, any chance you want to share your latest offset table?
Ive just installed the svo 30's and have noticed stuff is out a bit.
Many thanks,
Richard
ringram: just use my spreadsheet, i used it for my svo 30s, punched in the numbers and it's been that way ever since. works perfect
I used your table for IFR, but didnt realise it did IOS as well..?
oh the OTHER offset... sorry ;) it doesn't do that one, i just use the stock one from 26.4 setup for that, and trims came back right about perfect after the swap
Ok cool. Ill see if Joe can share what he has, otherwise Im running an earlier one posted in this thread. Just want to make sure things are as nice as possible before tuning up again. It was pretty close till I put in the new t'stat and drop the temps and messed with spark advance... now the tune is all out, so just wanted to get the offsets right so that fueling was bang on going forward.
Quote:
Originally Posted by ringram
Email me.