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Re: Is there a such a thing as cam surge in sd lt1’s
Oh, that's cool that you made that spreadsheet... interesting how things can come full circle back around on the internet!
I think you're running the $EE mask on your ECM. I have that as well for Tunercat and Tunerpro. Ordinarily I'd say you'd have to play with the accelerator enrichment to get rid of tip-in issues, but it's strange how that mask doesn't seem to have any accelerator enrichment tables in it. I'm out of my element on that though, so I can't say for sure. Maybe they just baked it right into the main fueling tables somehow.
On my Gen1 SBC with LT1 style Miniram intake, pretty much all I had to do was grab the $DA3 LT1 AE values (93 LT1 Camaro 6-speed), copy and paste them into the old TPI $8D calibration verbatim and I have perfect throttle response. I'm also running a 112@.050 cam.
Any rate, when I went looking for 30 lb injectors, I made absolutely sure the ones I was buying had factory Bosch data behind them. My $h!tty experience with data-less injectors convinced me I did NOT want to be doing guess work on what values to use.
Re: Is there a such a thing as cam surge in sd lt1’s
Originally Posted by ACE1252
The injector offsets were calculated by me using what I learned from Banish's DVD. That is my spreadsheet in the link for post #45. AdsoYo used them to help get his injectors dialed in. They are for FMS 30# "fat" redtops. I'm not sure if they will work right with the bosch orange tops. Sucks that most injector manufacturers don't put out calibration sheets. That's why I moved to the Ford injectors. They hand out the cal data.
I've yet to solve my tip in issue, but it's no where near the problem that the OP is having with his setup. I think my cam is 112 LSA and does run pretty decent.
Re: Is there a such a thing as cam surge in sd lt1’s
Yeah, you're pretty much pegged at 108 BLM everywhere after you get up to temperature, even at higher rpms where this cam is supposed to be coming into it's power band... which is odd considering your VE tables are overall significantly leaner than stock.
There seems to be something going on here besides a bigger cam...
Your ignition voltage being reported in the data seems awfully low at ~12.5V. It's what the ECM is seeing. I'd expect to be seeing a minimum of 13V, but typically should see around 13.5V if the alternator is charging properly.
What is the voltage at the back of your alternator when the engine is running? What is it at the injectors on the (+) wire? If the ECM is seeing a lower voltage than the injectors, it's going to be driving the injectors harder thinking the injectors are seeing low voltage (this is where the voltage offset table comes into play). The lower the system voltage, the longer the on-time the ECM commands. In which case, you'll get an excessively large base pulse width and wouild explain this 108 BLM...
I questioned that, and whether your tune was or was not based on vacuum compensated fuel pressure. You never answered that. That would certainly explain over fueling.
I questioned that, and whether your tune was or was not based on vacuum compensated fuel pressure. You never answered that. That would certainly explain over fueling.
my gauge says about 44psi mostly. Racetronix fuel pump new filter regulator (gm)
no clue on what the tuners did since I no longer talk to them. Always saying it’s not there tune it’s something on the car.. funny how all I did was put those offsets in and car runs hell of a lot better even if it’s rich
Re: Is there a such a thing as cam surge in sd lt1’s
Originally Posted by ULTM8Z
Yeah, you're pretty much pegged at 108 BLM everywhere after you get up to temperature, even at higher rpms where this cam is supposed to be coming into it's power band... which is odd considering your VE tables are overall significantly leaner than stock.
There seems to be something going on here besides a bigger cam...
Your ignition voltage being reported in the data seems awfully low at ~12.5V. It's what the ECM is seeing. I'd expect to be seeing a minimum of 13V, but typically should see around 13.5V if the alternator is charging properly.
What is the voltage at the back of your alternator when the engine is running? What is it at the injectors on the (+) wire? If the ECM is seeing a lower voltage than the injectors, it's going to be driving the injectors harder thinking the injectors are seeing low voltage (this is where the voltage offset table comes into play). The lower the system voltage, the longer the on-time the ECM commands. In which case, you'll get an excessively large base pulse width and wouild explain this 108 BLM...
car has always been 12.5v even with new battery and alternator but stereo system was on though
Re: Is there a such a thing as cam surge in sd lt1’s
Originally Posted by grabbem88
Also one offset I’m lean and this offset I’m rich
so I can’t answer that since everything is basically wrong
So I'm confused now...
Which bin was causing it to run lean? The bin you're saying that's associated with this latest data log has an injector voltage offset value at 12.5V of 675 microseconds (0.675 millisecond) and is still pig rich.
The factory offset value is 4500 microsecond (4.5 milliseconds)! If you ran that bin, (all else being equal) I'd expect you to be belching raw liquid fuel out the exhaust.
So which bin were you running where it was lean? And do you have a datalog from that bin?
Re: Is there a such a thing as cam surge in sd lt1’s
Originally Posted by ULTM8Z
So I'm confused now...
Which bin was causing it to run lean? The bin you're saying that's associated with this latest data log has an injector voltage offset value at 12.5V of 675 microseconds (0.675 millisecond) and is still pig rich.
The factory offset value is 4500 microsecond (4.5 milliseconds)! If you ran that bin, (all else being equal) I'd expect you to be belching raw liquid fuel out the exhaust.
So which bin were you running where it was lean? And do you have a datalog from that bin?
I already gave it to you. All I did was yank their offset for the one you supplied me with
Re: Is there a such a thing as cam surge in sd lt1’s
Originally Posted by ULTM8Z
The bin and data log you gave me showed pig rich (BLMs pegged at 108 with the integrator WAY below 128, meaning it was even richer beyond that).
The bin you gave me before that had the stock offsets.
So I'm curious what the other bin was with the other guy's offsets.
I understand the BLM thing but afr driving was 13.5-14.1 now wot was 11.2 and idle was 11.8-13.4
if those were stock offsets that’s what pcmforless uses we did not change them
Solomon tune offsets are different but injector flow rate is 27 I took Solomon tune today and put it at 28.5 and it did run better but nowhere as me punching the offsets you gave me on the pcmforless tune. This is what happens when we have too many chefs in the kitchen cause it’s getting crazy...
im going to take 5% fuel from my idle and take 10% from 3-7000rpm in my PE vs rpm table.
on my ve tables I’m not sure if I should multiply.84 off my entire ve tables per the 108/128 or go off my wideband which is 13.3
Re: Is there a such a thing as cam surge in sd lt1’s
I have the two original bins per each tuner
the rest are what I’ve been piggy backing off of per pcmforless tune
the Solomon tune hasn’t been messed with that much. And was my dyno results
btw all my plugs look or have looked like this all 24 plugs
