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Discussion Starter · #1 ·
I got my car dynoed today and kinda disappointed with the results.

This one's from last year: HP 234....TRQ 274....No AFR was taken

Mods: MRT catted h pipe, Flowmaster 2.5" catback and K&N
Air Filter

Today: HP 242...TRQ 272..AFR: [email protected] WOT

Same mods as above Plus:O/R H pipe, UDP,T/A(14' deg) ,Plenum spacer and 4:10's..

I only gained 8 HP from the added mod, what gives? and with the AFR of 11.0 is that very rich?....any input is appreciated.
 

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Your problem is defintely your air/fuel ratio. Mine is 12:1 supercharged. I bet you will gain another 15rwhp if you take some fuel pressure out.
 

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holy cow that's a rich A/F ratio. Get you ride tuned and you'll pick up some good power just from straightening that out.
 
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NoSlow5oh said:
Your problem is defintely your air/fuel ratio. Mine is 12:1 supercharged. I bet you will gain another 15rwhp if you take some fuel pressure out.
Don't change the fuel pressure. Just adjust the MAF transfer function.

On an N/A car you can run it at lot leaner then that. Your car problaby went pig rich when you put the O/R pipe on. It happens. You just need a tune. Your 4.10's also could have absorbed some of the extra power you made .
 

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Discussion Starter · #5 ·
Mana4Real said:
Don't change the fuel pressure. Just adjust the MAF transfer function.

On an N/A car you can run it at lot leaner then that. Your car problaby went pig rich when you put the O/R pipe on. It happens. You just need a tune. Your 4.10's also could have absorbed some of the extra power you made .

I've always though that if you free up the intake and exhaust side of the car that it makes it run lean. I'm gonna throw in some Accufab plenum and throtle body and head to sacramento to get it dyno tuned and see what happens
 

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It does open the motor up and let it breathe more, but that doesn't always mean it's gonna go lean. The EFI on the cars will monitor the exhaust O2 content and determine if the car is running lean or rich and adjust to a certain extent. That's where I'm at now. The stock tune is maxed and I need to have a tune done on it because my AFR is a little lean in the upper RPM band so it's costing me power.
 
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bloodyshin said:
I've always though that if you free up the intake and exhaust side of the car that it makes it run lean. I'm gonna throw in some Accufab plenum and throtle body and head to sacramento to get it dyno tuned and see what happens
Nope... That's not always the way it works... Computers are weird like that aren't they?
 
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I'll probably catch some **** from saying this, however, DO NOT get caught up in the dyno game. Dyno's are great for tuning, however, don't get hung up over them.

Want to know if you lost horsepower? Take it to the track.

Ok I'm done ranting now.

-Tim
 

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I agree wholeheartedly!!!! Dyno numbers don't amount to a pile of SNOT. The ONLY number that matters is how fast you can go 1320 feet!!!

I beat a car that "dynoed" over 100 horsepower and 85 torque more than my car . . at the track . . . I have the timeslip . . . :winks

GO TO THE TRACK YOUNG MAN . . . DON'T BE A BENCH RACER!!!!!
 
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bloodyshin said:
I've always though that if you free up the intake and exhaust side of the car that it makes it run lean. I'm gonna throw in some Accufab plenum and throtle body and head to sacramento to get it dyno tuned and see what happens
Are you gonna go to force fed performance? I heard they are pretty damn good. Badass is right about the track being the only way to tell if you really gained power.
 

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The track can't tell you your air/fuel ratio can it?
 

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No the track can't tell you diddly about your AFR, but it can tell you worlds about how the car is doing overall. Make sure your AFR is right before you go though, lots of people have gone with goofy AFR's and paid dearly for it.
 

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Mana4Real said:
Don't change the fuel pressure. Just adjust the MAF transfer function.

On an N/A car you can run it at lot leaner then that. Your car problaby went pig rich when you put the O/R pipe on. It happens. You just need a tune. Your 4.10's also could have absorbed some of the extra power you made .
I may be missing something. For him to adjust his MAF transfer function, he would need a custom tune right? I didn't see where he already had one. Are you suggesting he needs to get a custom tune just for the a/f ratio? What would you need to change the MAF transfer function? A new chip or reflash? I've always thought dropping the pressure a little bit was the easiet way to lean the mixture. Is there something wrong with doing that?
 

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Discussion Starter · #15 ·
Mana4Real said:
Are you gonna go to force fed performance? I heard they are pretty damn good. Badass is right about the track being the only way to tell if you really gained power.
Yeah I'm going to force fed performance like you suggested to me awhile back, their the closes one to Reno. Is there anything I should tell them when I get it dyno tuned or do they ask you want you want done to it? as in turning off the egr, trac control and stuff like that?
 
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bloodyshin said:
Yeah I'm going to force fed performance like you suggested to me awhile back, their the closes one to Reno. Is there anything I should tell them when I get it dyno tuned or do they ask you want you want done to it? as in turning off the egr, trac control and stuff like that?
That's up to you. Just let him do his thing. He knows what he's doing.

Noslow- Well, since he's on the dyno, he may as well get it tuned. That's all. Taking out fuel pressure also effects the entire fuel map. If you change the transfer function, you are mostly messing with high air flow anyways. So you would really want to run richer
 

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Egr

What we use one of these plates to block off EGR? would it do any good for performance? Where i live, i don't have to worry about emission test or any of that bull. So, should i block it off or would it cause me problems?
 
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