175/75 installed feel slower

[Ross@Flyindiesel]

well while i have the tranny thread going i thought id post up and ask. we had 175/stock in there from warren and man the truck would just pull its *** off! ran awesome and would keep up with my 6.4 pretty good. yea i would still kill him but kept up alot more than i thought. the truck would throw you back in the seat until you let out. anyways finally got around to putting nozzles on 75% and after installed the truck doesnt have the put you back in your seat power. now we havent gotten the truck tuned yet for them as thats happening friday at tsd on the dyno but i would think even though the truck isnt tuned for them yet it would still have awesome power! its just matts slr x. also the egts are like 450-500 at idle. its it just because we havent gotten it tuned or is there something possibly wrong? its still on the stock turbo.

 

[Derek@Vision Diesel]

In my opinion it shouldnt be pretty damn smokey with stock nozzle tuning and larger injectors.
Pulse width is opened up with stock nozzles to use as much of the fuel as possible in a reasonable amount of time.

Having that same pulse width with larger nozzles would make it empty a lot more fuel under the same condition, possibly drowning itself? But you would see lots of smoke if that were the case.

This is about the easiest way to explain it. Have any way to watch fuel pressure?

Sent from my DROID4 using Tapatalk 2

 

[Ross@Flyindiesel]

yea fuel pressure drops from 60 psi to about 55 or so. its got an airdog ii and rr on it though. its really smokey down low. bro said it will boil the tires from a stop but mid to top end just feels super sluggish. he said its like he is in a stock truck with a tow tune on it if he is going about 60 or faster and punches it

 

[Pizza pig]

The larger the nozzle, the less bottom end toque you will have. This is why you're getting these results. Get it tuned right and you will love it, i can guarantee it. I loved the 75 nozzles daily driving, was a dream, and zero smoke with chris behind the computer.

 

[windrunner408]

I would say there has to be something with the tuning. I agree with Derek to check the fuel pressure to see what it is doing. Hope you get it figured out man.

EDIT: posted too late.

 

[Ross@Flyindiesel]

i think it might be drowning its self because sometimes you sit at a stop light and it will bogg down for a sec and then rev up to 1k and come back to normal idle. its not all the time just kinda has a mind of its own. i just wanna make sure its the tuning and not something internally wrong.

 

[Powerstrokeracing]

For the erratic idle, could be air or IcP sensors going bad act like that..

 

[05wh250]

Are the injectors the same ones with different nozzles or different injectors?

 

[Ross@Flyindiesel]

same ones just different nozzles. and funny you mentioned icp. it went out the other day. truck wouldnt start so i took it out slammed it on the table put it back in and truck fired right up been fine ever since. i did however pull the wiring harness over to give the plug some slack so maybe in the wiring harness but its runnin fine right now as far as firing up

 

[motoxracer42]

I highly doubt it's drowning itself. I've ran stock files with nozzles that are much larger than that. Are there any contribution codes? I know my truck felt extremely slow with 205/100s and after driving it awhile it has two injectors randomly acting up. When they fire correctly its awesome but when they don't it's slower than mikaelas tunes 6.0.

 

[Ross@Flyindiesel]

not that i know of but havent really checked either. they ran great before we pulled them and did the nozzles. but im not going to rule that out. i guess after tuning tomorrow we will be able to tell if its just tuning or something going wrong

 

[the chad]

my question is why the hell are the egt's 400-500 at idle!?

and my truck ran like complete **** on my old tune before i got it updated the new injectors

 

[Ross@Flyindiesel]

Well laid down 470hp and 989 tq. We tried everything and couldn't break the 475 mark. It's running out of air up top.

 

[Fox hunt]

Well laid down 470hp and 989 tq. We tried everything and couldn't break the 475 mark. It's running out of air up top.

Is that after a new tune?

 

[Ross@Flyindiesel]

yea