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I am wondering what exactly changes in a tune using $8D bin when you change your injector flow rate,
I recently went up to 30lb injectors from 24lb, I changed injector flow rate in the tune, data logged and
retuned, I noticed my VE is maxed out under most the upper map area, with 24lb I was only maxed out in a few areas
I still need to tune with the new 30lb injectors at WOT using my WB
I would think ve would be much lower with the 30lb injectors.
First attachment is bin with 30lb injectors
Second attachment is bin with 24lb injectors
90 Corvette
385 TPI
AS&M Runners
comp cam 08-302-8 cam
Long tube headers
mild porting on 113 heads.
Last edited by eutu1960; Jun 30, 2023 at 02:16 PM.
Also here is Dyno sheet with 24lb injectors, the dyno's afr is way off from my WB, the dyno operator thinks there is air reversion on his WB giving incorrect readings
at my max torque on I am around 13 to 13.5 afr going by my WB
This is a gray area for me, I just do and don't ask. It appears the injector offsets have been unaltered but I don't see that making such a significant impact on VE in the areas you're asking about.TBH there's hundreds that have thrown in a new set of injectors on an unaltered bin and haven't looked back.
I am wondering what exactly changes in a tune using $8D bin when you change your injector flow rate,
To answer this specific question:
When you change INJ flow rate to match bigger INJ and everything else stays equal in your tune (BIN), the actual INJ will open less (in terms of ms) for same amount of fuel required. Now that's the theory. In reality, there are variations, and yes, you might have to retune your VE table. Why? Because the theoretical delta between your old INJ vs new ones (24# vs 30#) is only on paper. It might be otherwise once it's installed on your engine. Flow rate is calculated using a specific fuel pressure. Some injectors use 43.5psi, some 58psi or even 39.15 psi. There is a conversion formula that I don't have off hand. Easy to look up if you take the time. There are also other factors that makes the transition not as easy as just changing the INJ flow rate such as INJ offset for voltage and low BPW. They also need to be updated in your BIN based on manufacturer datasheet.
Last edited by SbFormula; Jul 1, 2023 at 10:02 AM.
Also here is Dyno sheet with 24lb injectors, the dyno's afr is way off from my WB, the dyno operator thinks there is air reversion on his WB giving incorrect readings
at my max torque on I am around 13 to 13.5 afr going by my WB
Seems a bit low on HP for a 383 TPI. Or am I out of line? You should get over 300 easily.
I recently went up to 30lb injectors from 24lb, I changed injector flow rate in the tune, data logged and
retuned, I noticed my VE is maxed out under most the upper map area, with 24lb I was only maxed out in a few areas
I still need to tune with the new 30lb injectors at WOT using my WB
I would think ve would be much lower with the 30lb injectors.
First attachment is bin with 30lb injectors
Second attachment is bin with 24lb injectors
Sorry for the early posts (deleted). I had not understood correctly. So....
If all you changed are the INJ and the INJ flow rate in the BIN to match, you forgot to adjust the INJ Voltage compensation and the INJ Low PW. You should have an INJ data sheet from the manufacturer to help you with that. Also, you could experience issue at cold start-up. At start-up, the ecm will fire the INJ with a fixed amount of PW. So if you increase INJ size to 30# from 24#, you will get 25% more fuel in theory. But, it might not be an issue.
If VE went up, it means the new combo "INJ + INJ Flow rate" removed fuel, thus you need more VE in the equation to add fuel. In theory it should not happen, but like explained in post #4, things can be different from theory. I see you are at 99% in your WOT VE. Be ready to need increasing over 100%, which can not be done with $8D. So you will have a problem. This is normal with your 383 TPI. It is a consequence of the harmonic wave effect from the TPI design. You will achieve over 100% VE. Check this one out. They achieved 120% VE!!!
Solution to this issue is decreasing INJ Flow rate in BIN which will results in INJ opening too much, which will result in need for lower VE. Example: if you decrease INJ Flow rate by 6.67% (30# to 28#), VE will have to be lowered, across the board, by same 6.67%. So 100% will go to 93.3%.
"Injector rate was set at 26 lbs/hr (instead of 32lbs/hr) to give ample room in the VE tables. The set-up achieves over 100% VE at certain RPM. The VE tables can not be set over 100%. By lowering the injector rate, VE has to be lowered also to achieve same INJ PW (all else being equal)."
Good luck
Last edited by SbFormula; Jul 1, 2023 at 09:56 AM.
Seems a bit low on HP for a 383 TPI. Or am I out of line? You should get over 300 easily.
Yes I am not happy with this build at all, at peak torque I need to add more fuel but was maxed out in my VE in that area thats the
reason I went with bigger injectors. i was about 13.5 afr according to my WB at around 3800 rpm.
Yes I am not happy with this build at all, at peak torque I need to add more fuel but was maxed out in my VE in that area thats the
reason I went with bigger injectors.
Sure!
Putting bigger injectors and changing the injector flow rate in BIN accordingly does absolutely nothing!!!!
Read post #8 for solution
You should get 340-360 at wheel
Maybe exhaust is too small or air intake
Have you mesures vacuum at WOT?
Last edited by SbFormula; Jul 1, 2023 at 04:38 PM.
Thanks for everyone's input, I am going to do what SbFormula said and change to injector flow rate to 28lbs, The injectors I am using are
Bosch 4 hole rebuilds from South bay fuel injectors (noisy as hell), I am now wondering if I might be better off going back to my 24lbs trick flow injectors
and trying the same thing. Anyway I will post a video on my YT Channel and here when I get it worked out.
Thanks for everyone's input, I am going to do what SbFormula said and change to injector flow rate to 28lbs, The injectors I am using are
Bosch 4 hole rebuilds from South bay fuel injectors (noisy as hell), I am now wondering if I might be better off going back to my 24lbs trick flow injectors
and trying the same thing. Anyway I will post a video on my YT Channel and here when I get it worked out.
I would stay with 30#
24# could max out at WOT
Shoot for 12.8 AFR at WOT and see what happens. You might have to go with 26# flow rate and lower VE accordingly.
There is definitely something wrong as your 383 should put out way more HP
Shoot for 12.8 AFR at WOT and see what happens. You might have to go with 26# flow rate and lower VE accordingly.
There is definitely something wrong as your 383 should put out way more HP
Peace
I think the restriction is the stock 113 heads, I did some mild porting , blended the seats some bowl work and opened up the ports a little, they still have the stock valve size in them 1.94 intake/1.5 ext. I did have them changed to stainless steel (no I did not have them flowed) that being said I did build this as a mild 383 in mind and would be quit happy with 300 hp at the wheels for the way I use it especially as I am getting older now.
I think the restriction is the stock 113 heads, I did some mild porting , blended the seats some bowl work and opened up the ports a little, they still have the stock valve size in them 1.94 intake/1.5 ext. I did have them changed to stainless steel (no I did not have them flowed) that being said I did build this as a mild 383 in mind and would be quit happy with 300 hp at the wheels for the way I use it especially as I am getting older now.
Well this is where I am at so far with my bin I still haven't played with the injector offsets just the VE tables, it seems to be developing a stumble right off idle and seems to be surging at idle just after I come to a stop so I will have to work on that.
I also noticed going through my log that commanded afr is showing going lean in some areas well going under load, I was logging it in overdrive in order to fill as many cells as posable.
I also noticed going through my log that commanded afr is showing going lean in some areas well going under load, I was logging it in overdrive in order to fill as many cells as posable.
Before you read, keep in mind it took me about 1.5 hours to come-up with all this information and I have not gone too deep.
A few things I noticed just for your information. That's from post #17 BIN and post #18 log
Your Air Injection Reaction System (AIRS) is enabled.
You have a WB AFR gauge I assume? If yes, be aware that the readings will be false when AIRS is pushing air to the ports. Happens mostly in OL.
Your fan is set at 201Deg.F... why? Looks like you have a 160Deg.F Thermostat.
Your EGR is disabled.
Your CCP is enabled
Initial timing set at 6* in BIN. Has to match your real set initial timing
Your HWY mode AFR is disabled but your HWY mode SA is not!
Your SA shoots up to 50* but is limited at 41.8* by the BIN. Your SA calculation needs adjustment I would say.
Cold SA is enabled
BLM and INT looks ok
Reason your Commanded AFR goes "lean", which I assume means it goes over 14.73, is because PE kicks in. You have your PE AFR programmed in such a way that it gives a higher than 14.73 commanded AFR. What it means in reality?... Not much. Commanded AFR can differ greatly from real AFR when in PE. You need an AFR gauge to monitor, or estimate based on O2 sensor voltage readings for WOT (I don't like that method but it's better than nothing). In PE, ECM is shooting in the dark. There is no feedback.
AFR estimate based on O2 voltage at WOT:
830 mv = 13.0:1
880 mv = 12.5:1
930 mv = 12.0:1
I noticed your never reached WOT so O2 voltage can be deceiving. You need 100% throttle opening.
Your PE settings are too sensitive. It kicks in too early at low rpm. Look at #5930 to 5958. You need higher TPS% threshold at lower RPM and less at higher RPM.
How PE AFR is calculated
PE AFR = 14.73 / (1 + %Change vs Cool + %Change vs RPM)
Example at sample #5930
14.73 / (1+ 0.227 + -0.3085)
14.73/0.9185
16.04
You get 16.26... close enough for me!
14.73 is extracted from your BIN. It's the Commanded AFR for INJ PW Calculation in the scalar.
It seems like you are going lean "for real" when in PE. You also get knock event and SA get retarded up to 7*. Check sample 9587 to 9616. Your SA ave was 23*!!!! You were only at 85% TPS but in PE. Ave O2 voltage was around 800... a bit lean.
That's all for now
Last edited by SbFormula; Jul 9, 2023 at 09:52 AM.
SbFormula thanks for looking through the log, I really did not expect anyone to spend that much time on it just take a look.
My air pump has nothing in it I deleted the blades in side but I will disable my air injection anyway.
I do have a WB I normally just eye ball it well going wot , I just got around to wiring it up to the ecm so I can data log the WB.
I use a 180F thermostat
I have no egr
I do use my ccp
My initial timing is set at the factory 6*
My WB is reading about 12.5 when ever I get on the throttle
I went ahead and reset my PE Enable TPS % Vs. RPM to the factory setting
I have been using this table to adjust my PE PE Change to AFR Vs. RPM I will change it back to what I had it in my last tune.
As far as spark advance is concerned I am not sure what to do about that even when the engine was stock with stock tune it would do that.
Thanks for all your help I am going to make the changes and get some more logging in.
SbFormula thanks for looking through the log, I really did not expect anyone to spend that much time on it just take a look.
Anytime!!!
That's the issue. People are under the impression you can just take a look at things. Tuning is complex. TPI systems are sensitive to any malfunction and can do funky things. It triggers the "throwing parts at it rabbit hole" that I see too often on these forums. Scanning and understanding the data is key.
My air pump has nothing in it I deleted the blades in side but I will disable my air injection anyway.
Make sure you zero-out: Rich/Lean Reduction Volts for AIR (0x49D)
I use a 180F thermostat
It seems like your CT is at 170Deg.F when cruising. I don't have any data when your are idling. I bet you, CT spikes to over 200Def.F. Lowering the fan will help maintaining CT constant. You can also wire the second fan to the '7730 ecm. Just search the forums. Personally, I like CT to be as constant as possible when tuning.
My WB is reading about 12.5 when ever I get on the throttle
Interesting! "Get on the throttle means"? For me it means: for a real test you need a hard acceleration with 100% TPS (WOT) on the datalogger and at least going through 2-3 gear on your AT to max RPM. You can't just glance at the WB gauge. You need to monitor it. If you can data log it it's way better.
As far as spark advance is concerned I am not sure what to do about that even when the engine was stock with stock tune it would do that.
Yep SA is a real pain on '7730 $8D. Lots involved.
Make sure you disable SA HWY mode:
You can put max value in one of these:
Min. CT
Min. RPM
or zero out table Deg. vs MAP (0x1AB)
I tried modifying the xdf and my adx files to read the WB but no luck, I can data log my WB via 1320 Bluetooth adapter
using there software but everything will be in cvs but at least I can log it and look at it later.
