d_mina

If I were to tune my car with a 2.25in exhaust system and then upgrade to a 3in. exhaust system, would that cause a big enough change in airflow to necessitate another dyno tune?

Muckman

iTrader: (2)

I would. Thats a big jump.

B18C1CYA

i would do any upgrade you are going to do then tune, thats what i do

95GSRTT

my tuner says it shouldnt need to be retuned, since boost is boost. Your not making more boost, just more hp.

B18C1CYA

boost will come on sooner and the fueling will need to be adjusted

Muckman

iTrader: (2)

It can depend on how its tuned too. I have my AEM tuned with a method known as "Boost comp" that uses manifold pressure as a fuel trim multiplcation. Boost adjustment would not affect my tune.

95GSRTT

ya i think thats why he says its ok with my hondata. I believe with a Safc you would need to.

Mase

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95GSRTT &raquo;</TD></TR><TR><TD CLASS="quote">my tuner says it shouldnt need to be retuned, since boost is boost. Your not making more boost, just more hp. </TD></TR></TABLE>

lol your 'tuner' is wrong.


on higher whp cars, changing the exhaust can have dramatic effects on AFR and will need to be retuned....

on lower whp cars, a afr of .2-.3:1 change can easily be expected

turbo*s2k

what would happen if you tuned open downpipe, and then bolted up a 3" exhaust?

Would it run richer?

I'm pretty sure that if tuned with an exhaust, and if you ran open you would run a bit lean right???

Mase

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TurboChrgd_Civic &raquo;</TD></TR><TR><TD CLASS="quote">what would happen if you tuned open downpipe, and then bolted up a 3" exhaust?

Would it run richer?

I'm pretty sure that if tuned with an exhaust, and if you ran open you would run a bit lean right???</TD></TR></TABLE>

bingo, you're correct

better to be rich than lean

95GSRTT

is it true that hondata would be able to kind of compensate for that or no? also my car would only make like 220 whp

PolySquared

I had to re-tune my car when my catalytic converter was removed. That may help you with your question. I'm running Hondata as well

95GSRTT

Well how about this, right now im running a hollowed out stock cat. and 2.25 cat back. Im getting a 3" car sound cat and 3" exhaust system. That should pretty much cancel out right? lol I know dumb question, but Im wondering b/c spending 100 bucks a pop and retuning EVERY time I add a part gets rediculous.

h22 civic

when ever i had my cars tuned and then ran open exhaust i always had 2 programs

sharkcohen

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95GSRTT &raquo;</TD></TR><TR><TD CLASS="quote">my tuner says it shouldnt need to be retuned, since boost is boost. Your not making more boost, just more hp. </TD></TR></TABLE>
Wow, time for a new tuner.

turbo*s2k

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">

bingo, you're correct

better to be rich than lean</TD></TR></TABLE>

Thanks Mase!