will i need a new tune?

broken_joke

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Nov 24, 2004

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carriere, ms

Jul 10, 2005

#1

• Jul 10, 2005

• #1

i recently purchased 42# injectors for my 351w setup. i installed yesterday and the drive is good, power feels good also. doesn't feel like it is falling off like the 30#s. will i need a reburn to maximise power output?

at the dyno it seemed to struggle to get to 360 at the wheels. will the upgrade produce some much better numbers at the track and dyno?

 

W

wytstang

Mustang Master

Mar 14, 2004

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Summerville,SC missing South Fl. weather :(

Jul 10, 2005

#2

• Jul 10, 2005

• #2

If it was starving for fuel then yes it will net you hp/tq and better times. I would think as long as you mass air is calibrated to accept 42# injectors it will be fine. But if you want to sqeeze out every little hp/tq than a reburn is in your future.

 

Venom351R

Founding Member

Apr 27, 2002

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Jul 10, 2005

#3

• Jul 10, 2005

• #3

Only way you will really see a peformance increase is if the injectors before were just not cutting it and you were not getting enough fuel. That happend w/ mine my #30's could just not keep up once I reached 5,000 RPM's but w/ the #42's I was able to get better dyno #'s. As far as your tune you really dont need to reflash it when you just switch injectors it should be ok, just make sure you have a matching MAF.

 

mytight95

Active Member

Apr 11, 2003

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Dothan,Al

Jul 10, 2005

#4

• Jul 10, 2005

• #4

I am curious as to how us N/A guys can get away with 300 or so RWHP with 24# inj. without issues, and the blower guys have to have twice as much inj. so to speak.... This is an HONEST question...


thanks for info and enlightenment.


jason

 

Venom351R

Founding Member

Apr 27, 2002

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Jul 10, 2005

#5

• Jul 10, 2005

• #5

mytight95 said:

I am curious as to how us N/A guys can get away with 300 or so RWHP with 24# inj. without issues, and the blower guys have to have twice as much inj. so to speak.... This is an HONEST question...


thanks for info and enlightenment.


jason

Click to expand...

boost requires more fuel would be my guess. Im at 340-350 RWHP which on an N/A car #30's would be pleanty, but w/ my set up hitting 10 PSI the 30's just could not keep up.

 

mytight95

Active Member

Apr 11, 2003

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Dothan,Al

Jul 10, 2005

#6

• Jul 10, 2005

• #6

so do boosted cars run a fatter a/f curve or what.... once again i am just learning about the boost stuff...lol


jason

 

W

wytstang

Mustang Master

Mar 14, 2004

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Summerville,SC missing South Fl. weather :(

Jul 10, 2005

#7

• Jul 10, 2005

• #7

I think it has to do with boosted engines being put under a heaver load. You are cramming(sp?) x amount of psi's into these cylinder the load is pretty much 10 fold compared to n/a (this is just my thinking).

 

broken_joke

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Nov 24, 2004

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carriere, ms

Jul 10, 2005

#8

• Jul 10, 2005

• #8

alright! i guess i'll look into some cost for a reburn. i wasn't really sure if the injectors would affect the tune or not?
thanks!

 

final5-0

Mustang Master

Apr 6, 2003

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DFW Texas

Jul 10, 2005

#9

• Jul 10, 2005

• #9

mytight95 said:

I am curious as to how us N/A guys can get away with 300 or so RWHP with 24# inj. without issues, and the blower guys have to have twice as much inj. so to speak.... This is an HONEST question...


thanks for info and enlightenment.


jason

Click to expand...

Jason

Its all about airflow ............. well mostly airflow....a little fuel helps, lol.

A forced induction combo will "force" more air through the maf than it can accurately report to the pcm.

It goes without saying that you need the extra fuel to go along with all that extra airflow.

As for the comment about na combos with 300rwhp getting buy with 24lb inj's. Some are starting to find that are not "getting buy" with 24's and they do in fact have "issues".

Go hang out on some of the tuning sites and you'll see a few peeps with 24's who have found that their combos turned out to be more thirsty than they first thought.

Later
Grady

 

194stang

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Aug 11, 2003

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Jul 10, 2005

#10

• Jul 10, 2005

• #10

I changed the stock maf and inj to a pro-m and 24#s, and JMS said the chip had to be reburnt because of the different maf curves. Whether or not that matters since you seem to already have an aftermarket maf, I don't know.