This guy says keep original VE values when increasing displacement value
This is the HPTuners math I use to get VE at any point of the engines operation off of a calibrated MAF signal. 0.7875 is the cylinder volume of 1 cylinder of my 383 in Liters. Insert the displacement of whatever you are working with there. 8 is the number of cylinder, if you are working on a 4 or 6 change as needed. I also calculate CFM off MAF Flow and Temperature as a reference.
As shown in the video I was able to setup a base tune for a starting point in a matter of minutes. I was able to start the engine without issue and put it through a heat cycle. At that point I changed the oil/filter and looked everything over for any leaks. From there I started driving it and tuning within a couple short drives I had it very close AFR wise and was able to start making wot pulls. From there I had the AFR where I wanted it and started adding timing while checking plugs. This is a guy that had maybe a year of experience tuning with hptuners at the time. My first tuning experience with hptuners was a cammed procharged sbe. I never hurt that motor, but only took it up to 14 psi before I decided to pull it and sell the good running ls1. I put that money towards building a forged ls3 block.
Keep in mind the 3 times I used this technique(once for myself and for two friends) they were all speed density tunes for boosted applications no maf involved. I also did both start up tunes for my friends for free. I've done plenty of sbe cammed 6.0 and 5.3 truck tunes using a maf locally, but what I did in the video was obviously not needed on those tunes.
Last edited by BCNUL8R; Jan 16, 2023 at 02:19 PM.
The Best V8 Stories One Small Block at Time

@NicD is correct about the history lesson and formatting of V and cylinder volume being linked. Heck, I even pointed this out in my original GM Tuning DVD ( with that segment that's now on streaming HERE) It's indeed a "feature" in HPTuners that shifts the VE displayed values automatically in an effort to "help" the user. In my video, I showed pretty much the same thing where we change the cylinder volume and then re-insert the original VE values as a starting point for calibration. Chances are, if you have a stroker motor and bigger cam, you'll be changing them anyway, but at least you start with a more reasonable estimate.

@NicD is correct about the history lesson and formatting of V and cylinder volume being linked. Heck, I even pointed this out in my original GM Tuning DVD ( with that segment that's now on streaming HERE) It's indeed a "feature" in HPTuners that shifts the VE displayed values automatically in an effort to "help" the user. In my video, I showed pretty much the same thing where we change the cylinder volume and then re-insert the original VE values as a starting point for calibration. Chances are, if you have a stroker motor and bigger cam, you'll be changing them anyway, but at least you start with a more reasonable estimate.
I usually just work with the raw g.K/kPa VE table.
ive never used hpt but i always thought (in my first hand experience with efilive) that the ve table was not displayed relative to the cyl volume variable. im curious now and going to pull up those two tunes and see.
and for some of the early posts in this thread, wow, heres a gift
I also released a commercial version of my PFI Injector Test Bench that creates exact plug and play calibration data from any set of injectors in just minutes. This should really change how we approach ECU calibration. Once enough shops have these on hand, users will be able to quickly get precise data for their specific set on injectors, saving time and headaches during the tuning process.
Beyond that, I have a bunch of mostly emissions-based projects in the background. I still love playing with the go-fast stuff, which is why you occasionally see me in places like this helping enthusiasts who want to learn.
I also released a commercial version of my PFI Injector Test Bench that creates exact plug and play calibration data from any set of injectors in just minutes. This should really change how we approach ECU calibration. Once enough shops have these on hand, users will be able to quickly get precise data for their specific set on injectors, saving time and headaches during the tuning process.
Beyond that, I have a bunch of mostly emissions-based projects in the background. I still love playing with the go-fast stuff, which is why you occasionally see me in places like this helping enthusiasts who want to learn.
I'd like to see more of the guys with 20+ years of real world tuning experience come back. Joecar probably doesn't remember either, but he gave me some pointers early on that helped me out as well. I'm really appreciative of everything I've learned from some of the long time members here and also wish we could bring it back the way it used to be. I've found some good info that is vehicle specific on the book of faces, but the discussions aren't nearly as technical/informative as they used to be here.
I'd like to see more of the guys with 20+ years of real world tuning experience come back. Joecar probably doesn't remember either, but he gave me some pointers early on that helped me out as well. I'm really appreciative of everything I've learned from some of the long time members here and also wish we could bring it back the way it used to be. I've found some good info that is vehicle specific on the book of faces, but the discussions aren't nearly as technical/informative as they used to be here.













