C_Rules

iTrader: (7)

I have an LT1 bored .030 over so now its a 355. I never changed the cylinder volume in the ecm constants table in tunercats. Anybody know what is the cylinder volume for a 355? stock is 717.25 but I know since it's been bored out i know that number has changed and I dont know how to calculate the new number. anybody know what it would be or the formula to calculate it?

matt94z

iTrader: (49)

I'm not sure about the volume, but most tuners that I know of don't change that table even with strokers.

C_Rules

iTrader: (7)

yeah i had taken it to a tuner a told him it was a 355 and he didn't change it. also most bins i have seen leave it alone. i wonder why that is.

matt94z

iTrader: (49)

They say it is easier to tune. I really don't know why. I have a formula somewhere that tells how to calculate it, but I haven't found it. If I do I'll post it up.

z28hustle

what would you be doing with the cylinder volume?

LT1Falcon

iTrader: (3)

350/717.25 = 355/X

X = cylinder volume

350/717.25 = .4879749

so .4879749 = 355/X

.4879749 * X = 355

355/ .4879749 = X

X = 727.49643

727.49643 = cylinder volume

if you can understand all that, good. if not, i can pretty much garuntee you its right. now im not saying that you should change it because i dont know. im just given you the formula and i did it for you too. im not sure thats the easiest or most used formula, i just made it up on my own but its basic algebra

LT1Falcon

iTrader: (3)

its just a setting on your ecm. i use tuner cats and ive seen it on there too. i guess the computer needs to know for some reason

infinitebird

iTrader: (11)

LT1falcon you got the value right. But it might be easier to understand this way. The cylinder volume is expressed in milliliters per cylinder. Knowing that's it's fairly easy to determine the correct value.

355 cubic inches = 5.81741 liters
5.8174 * 1000 = 5817.41 milliliters
5817.41 / 8 = 727.18 milliliters per cylinder

LT1Falcon

iTrader: (3)

yea i figured there was an easier way, i just didnt know exactly how many liters were in 355 cubic inches

infinitebird

iTrader: (11)

just use the google calculator for things like that: http://www.google.com/search?rls=en&...UTF-8&oe=UTF-8

C_Rules

iTrader: (7)

so anybody ever changed this in cats?

C_Rules

iTrader: (7)

okay so lets say you have a 383 because your bored .030 over and have 3.75 inches of stroke. this means you would have

383ci = 6.27624551 liters
6.27624551*1000 = 6276.24551
6276.24551/8= 784.531 ml/cyl

but has anyone evr done this when tuning their car?