cylinder volume? used for anything?

[sarg]

We have a debate going on another forum and I just wanted a firm answer. Is cylinder volume used in any calculations? For instance if you changed it from .700 to .900 would it change fueling if all other fuel tables remain unchanged?

[Britt2020]

We have a debate going on another forum and I just wanted a firm answer. Is cylinder volume used in any calculations? For instance if you changed it from .700 to .900 would it change fueling if all other fuel tables remain unchanged?

Legend has it that it plays a small part in calculating dynamic cylinder air, such a small part that it in fact does nothing. Legend also speaks of it being used in identifying misfires. This is all legend of course and can only be speculated.

You and whoever you’re arguing with at whatever forum you’re arguing on need to debate something for which the truth is more attainable, like Bigfoot, Lochness Monster or Burt Reynolds hair. This is one of those,” this guy said it does this, but this guy says it does this, but when I changed it, it done nothing, yet." questions.

Maybe one of the big dogs will get on here and give a cut and dry answer.

[sarg]

So what was Banish talking about in the dvd when he referred to changing cylinder volume rather than rescaling the injectors to avoid a limitation in the ecu?

[eficalibrator]

It plays a HUGE role on determining cyl_air in speed density on the older systems. Newer systems retained the value for reference as a placeholder, but it really doesn't do anything. The way to tell is check and see if the units in your VE table are "% VE" or "GMVE". The older %VE (numbers typically 0-100ish) versions must multiply by the cylinder volume to get an actual airmass. When they switched to GMVE (numbers 1000-2000ish), the volume got baked into the numbers in the GMVE table, so the reference value scalar became redundant as far as fueling is concerned.

[sarg]

Greg about what year did they switch?

[Britt2020]

You and whoever you’re arguing with at whatever forum you’re arguing on need to debate something for which the truth is more attainable, like Bigfoot, Lochness Monster or Burt Reynolds hair. This is one of those,” this guy said it does this, but this guy says it does this, but when I changed it, it done nothing, yet." questions.


Hmm. Well I take back my statement.

If there is anyone in the world that would know, he just answered.

[sarg]

Went through and compared files for various year vettes and found that it seemed to have started in 2005 from what I can tell. 2005 was the first year vette that had the VE in the 1000's. Maybe different on other platforms. All the Camaro files seems the same from 1998-2002.

[vette_c6]

it does
always change the vol for each car you tune and get it exactly like what the car have

[cmt_cibarra]

Volume, i believe this will be used when you actually stroke the engine, for instance.. 350 to a 383 engine block. That will change the volume on the cylinder therefore you'll get some different readings since it's a different stroke and bore which change the volume....

Would you agree or disagree?

[ssdungeon]

Legend says change the volume but what about the Type for the older ECMs?
If the block is a 6.0 block stroked to say a 408
The Cylinder Volume is .83611
if the original engine was a 5.7 before the engine swap to a 6.0 based 408 should we leave the type at 5.7 or change it to 6.0? I have read posts that say leave it and others that say change it.

Got my answer today.

Dont change the Type just the cyl volume.

[ssdungeon]

Thanks James

But in your case your initial block never changed. You just stroked it.
My question is when you move from a 5.7 based block to a larger 6.0 or a 7.0 based block... whether you stroke it or not.
Say you put in a 427 would you change the Type?

[ssdungeon]

No he explains it above. GMVE does not matter as much for the cylinder volume.
VE tables matter.

My question is the engine "type" when changing the base block displacement should we change the type. Like putting an LS3 in an LS1 car regardless of stroke or bore.
I didnt mean to hijack the thread but since this thread was sort of relative I think itll help anyone else searching to find all the info in the same place.

I think you can tune either way even if you dont change the cyl volume but the VE will be HUGE or small. Thats my current issue. I can hardly wait to get off work to go plug in the cyl volume numbers and retune VE my car is running pretty good just a super high VE table like a BOOSTED car!!!

lol.

If you notice, Banish did not give you the definition of "older" systems where the value really makes a difference. However, I bet Greg has an idea in which instances it makes a difference. Knowledge is money though!

[kyphur]

I think it is a shame that the HP Tuners owners who built the software cannot tell us how this parameter is to be used. A little scary that they wrote the software to select this parameter however they are not in this case telling YOU what to enter for your specific application. They should offer a help line technician to answer questions by email or phone for people who lay down the money for their product. You are most likely going to be told that sometimes it matters and sometimes it doesn't so just try it several ways and see what happens - you know, give the motor what it wants.

I feel that way with a lot of the information given for the software. A lot of it is vague with references that are apparently known to the programmers but not to the lay-person. In one part of the app they reference something that they've termed completely different in another. You can come on here and ask but if it isn't something they can answer in just a few words in a post they don't even bother responding it seems.

[JamesLinder]

I know for sure now that the cylinder volume affects operation of the fuel injectors. If you enter larger than actual volume then it would cause a rich condition; smaller than actual volume would result in a lean condition - assuming all the other settings were correct for the specific engine build. So think "fueling" when entering this number whereas VE affects the amount of air you are telling the PCM that the motor can push through the motor for given MAP and RPM range.

[Maxwell Power]

How about the effects of a cam on cylinder volume?

Since the cam affects the charging coefficients and affects the amount of air in the cylinder, normally VE alone would cover this. However, when I stroked my motor I increased the cylinder mass correctly and I still had to add a ton to the VE table. Obviously a longer stroke makes an engine more efficient down low and it would have a higher VE, but the changes were large across the board. I'm wondering if the cam made a bigger difference than I was giving credit for.