Tiago

iTrader: (27)

I tried to get it to idle yesterday but with no luck only ran for 5 seconds at a time

using HPtuners, need to get it at least to run up to 2000 rpms just to get it ot hte dyno where the 3bar OS will be setup


Any help?..

thanks

foff667

iTrader: (2)

im assuming this is on the 99 TA correct? Have you considered flashing a 00+ OS that will allow you to do a true 3 bar tune?

Tiago

iTrader: (27)

I will once I get to the dyno... need to make it run as is to get there first

foff667

iTrader: (2)

try PMing rick at synergy he might be able to give you a heads up.

soundengineer

iTrader: (16)

if you have a 3 bar sensor in the car..then its just going to read lie its a 1 bar in the software...
0 volts will show 10kpa and 5 volts will show 94.34 kpa....
so you are going to have a 1/3 resolution VE with a 1 bar OS in there...
you will also need to chane your IFR tables to reflect that same change...
whats in 60 will be what needs to be in 20 ..... the rest is just a linear guess...

slow

iTrader: (7)

could you just change the map sensor offset and slope to allow the one third resolution to be the 1 bar that is used by the factory pcm?

Ryan

kbracing96

iTrader: (25)

I would stick the 1 bar MAP back in it, drive it easy to the dyno and change the MAP to the 3 bar there. IDK how hard they are to change on a car, but on a truck I can do it in about 5 mins. That way, you don't have to jack a bunch of tables around just to get it to barley run. My 2c anyhow.

SSpdDmon

iTrader: (10)

You might want to take another look under the hood of an LS1 f-body. We pretty much have to remove the intake to get to the MAP sensor since the back 1/3 of the motor sits under out cowl/windshield. Then there are the sharp pieces under the cowl that turn your hands into shreaded cheese if you don't have a pair of gloves that go halfway up to your elbows. I guess the engineers did us a favor by screwing over the mechanics....at least we have a somewhat decent front/rear weight distribution.

vanillagorilla

iTrader: (1)

Put it on when you get there. The dyno shop should have somebody that has done it before.

soundengineer

iTrader: (16)

yup...its easier to remove all teh **** on top of teh engine and take off teh intake to get to the MAP sensor...otherwise..you get shredded arms...

last time I had to do stuff on the back side of an ls1..when I got home..my wife asked me if I had gotten in a fight with a cat and lost..LOL

Tiago

iTrader: (27)

its easy to swap out for me....Victor Jr intake

BUT, the 3 bar sensor wiring harness is different from teh stock 1 bar, therefore I had to cut the connector and splice in a pigtail, so now I can't put the 1 bar back ....without rewiring it again.... tahts out of the question

wait4me

iTrader: (10)

you just have to change the map scaler to make the kpa read 100 when key on engine off. then it will work fine. I have a 2 bar on my lingenfelter transam and not even running boost. Im just too lazy to pull it back off.

SSpdDmon

iTrader: (10)

Or you can find out your elevation for your town (in feet).

Then, get a calculator and figure out ~ 10^(5-(h/50853.0183725)) where 'h' is your elevation. Then divide by 1,000.

This will give you your atmospheric pressure in kPa, which is what you should see when you floor it. I tried it with mine and it worked.

Lansing, MI = ~850 ft above sea level
Calculated pressure = 96.2 kPa
Observed pressure last night at WOT = 96 kPa



Come on Jesse....I thought you were on the ball when it comes to this stuff. j/k

wait4me

iTrader: (10)

If your key on engine off kpa is 100.

And your running wide open throttle is lower, That means you have an intake restriction.

Ive seen on one of my modded caddys 90kpa at wot!!!!! There was a little rubber boot in front of the airbox that would collapse under full excelleration... Pulled it and kpa went to 97.

Then pulled the airfilter assembly, and sure enough kpa shot back to 100... Well that and a 26hp increase from just removing that restriction.. Damn Gm cars.. lol


If you put in 188 in the map scaller for a 2 bar should put it right where it needs to be.

SSpdDmon

iTrader: (10)

True...but my point was if your atmospheric pressure is only 96.2kPa outside the car to begin with, then chances are you won't see anything close to 100kPa. I actually saw my 96kPa for a brief second. It was mostly 95kPa. Considering its still got the paper filter in it, I'd say there is minimal intake restriction.

What I wanted to ask was, does the offset stay the same when you change out a MAP sensor? I'd assume if you go from 1-bar to 2-bar, you just double the scaler based on your reply...

wait4me

iTrader: (10)

The barometer updating should fix any slight variance. That is why it is easier to just turn on the key and note what it says kpa is at, then just put in the 2bar and match that number by playing with the scaler a little more.

kbracing96

iTrader: (25)

Ha ha, I wish I could turn the key on and see 100kPa. Try 85 kPa, I got to make 2 lbs of boost, just to get to 100 kPa. Thank god for turbos

Sorry guys, I haven't been around many Fbodys. I live in truck country, but got some fast trucks

Tiago

iTrader: (27)

for anyone trying to get their car at least running to be able to get around until you put a real tune on it, like I needed, try this:


3bar MAP on 1 bar OS, double your entire secondary VE

it should at least start and idle, you can go from there adjusting from the LTFTs.
I had to reduce my minimum MAP for LTFTs to work due to the 3bar scaling...but worked like a charm, now to schedule a dyno session

Pro Stock John

iTrader: (34)

t-r-a-i-l-e-r

Tiago

iTrader: (27)

buy me one, and a truck too while you're at it