Hey guys,

took my untuned Vortech out on maiden drive around the neighborhood today.

I know "i need to get it tuned" is the answer to this question, but I wanna know why...

so i can rev and stay off boost, but as soon as I punch the gas it lurges forward then stumbles just like it does when VDC kicks in (no vdc light though). Feels like the throttle plate is snapping shut. Is this bc I am maxing out the MAF voltage. I have a MAP sensor but havent switched over to it yet.

I did get it to accelerate into boost 1 time, but everytime after that, it feels like that throttle plate shutting, or fuel cut or a something.

I got that drive out of my system, so I'm just waitin to get tuned.

 

What engine management are you running? possibly a fuel problem. I don't think the MAF would max out until after 5k rpm

 

Wait for the tune before you blow it up....

 

ya i'm not goin to mess with it anymore. UTEC, 650cc injectors scaled to -17 in column 0, but I havent put in my Walbro 255l yet

i just wanna try to learn some of the methods behind tuning.

Thanks!

 

Do you have the Walbro already? I have one for sale, already installed and drilled out, etc. in a sending unit - ready for a quick swap into the tank...it's in the marketplace.

Other than that - the best way to learn is NOT to run the car untuned...

 

i have a walbro.

so how do people learn to tune then?

 

Usually as a tuner tunes their car...lots of reading, etc. You want to try and make sure your tuner explains what they are doing and why. It will be the best education you can get.

Also - without a wideband sensor, gauge and logging - you'll never be able to tune it yourself - unless you rent a dyno, etc.

Let me know if you have any questions otherwise...but please play it safe - your car will appreciate it

 

i have a wide band and a logger.

there of tons of people that street tune. lots of guys on the suby forums street tune as well.

I will just make sure to ask my tuner lots of questions

 

Fuel is very easy to adjust since you have wideband as long as you have a conservative timing map to start with and a good logging software. I think there is no one who will put more time on your car but yourself (Only if you have the time..hehe). There are so many things to consider and I would have typed them all but it's Sunday Morning and I'm lazy do a lot of research and you can tune your car on the street as long as you have a Wideband and EGT. The EGT gauge will help you if you want to play around with advancing/retarding your timing. Retarding the timing doesn't always equate to safety because it does raise your EGT to a point. Make sure you have a big space that you can run coz you'll end up running 100mph when you want to properly tune your higher RPM range. You also need someone to help you tune for safety. It will be hard to get info out of your tuner since Tuning is an Art and kinda proprietary, it will be hard to get all the secret out since that is how they make their $$$$. The good thing is that Utec is easy to tune as long as you know what you are doing. Hint, READ the Utec manual 10X and that is a good start.


Check this link. This will help you scale your injector if you can't find a basemap for your setup.

https://g35driver.com/forums/showthr...reddy+base+map
Good luck.

 

Was this a self install ?????

If so...take it to a shop that can check over your work and find the problem . You didnt get something done right . If a shop did the install , take it back . Going to the tuner now , he will more than likely beat his brains out trying to figure out whats going on and he'll be charging you for trouble shooting your car and not tuning it .

 

+10000

Also - was your kit NEW from Vortech or a used kit? If it was used at all, you are likely running the old owners tune, or they may have erased the the tune as well.

Either way - it's either a tune issue, maybe even a belt slip/leak, etc. - It does sound like fuel delivery...

 

There is for sure something not right . Trying to figure it out over the internet aint going to work 99.9% of the time . You are going to have to go thru the whole install checking . Then pull the maps off the SS box and check them . They could have ereased the whole tune off of it...who knows .

Oh the joys of trouble shooting !!!!!!!!!!!!!!!!!!!

 

well its not tuned, it's tuner kit from PF, stock fuel pump, scaled 650cc injectors.


Just a quick logged drive shows that as soon as i get on boost my AF goes to 10. Thats why the motor bogs out.

There;s nothing to fix, just tune.

 

Just take it to Jeremy asap and get it fixed b4 you blow it.

 

yes, dont get on it please. i dont want to see a blown motor thread...


see ya soon!!