FONK

so i just put a cut-out on my car,we routed it straight off the turbo and goes down to the side,i was tuned for a 2 1/4 xhaust,do i have to re-tune my car for the cut-out,since its a big difference??????and is there any tricks i can do with the tuninig,because i ran the cutout straight off the turbo so theres no o2 bung to plug a wideband.......

drintegra

should have ran the cut out further down to give room for the bungs, it might affect drivability now since there is no O2 reading. the cut out on a friends car did not change the reading too much maybe .2-.3 AFR points. It went from like 10.8 -11.2 through out the power band.
Get an AFR meeter like PLX 300 or UEGO. This will give you an accurate reading and a baseline.

FONK

ya,i was goin to but i my i have 3 inch downpipe and then it bottlenecks to a cat then to a 21/4 xhaust

yee SERIOUS

iTrader: (1)

don't you just need one o2 bung before the cutout for wideband tuning? i'm sure you can just get one welded on. how far is your cutout from the turbo? 10-12inches?

FONK

its about 10 inchs straight

yee SERIOUS

iTrader: (1)

get a pic for us

ccivic

retune.

FONK

so you think it will make that big of a difference?????

FONK

so you think it will honestly make that big of a difference???

SovXietday

You need to get your O2 inbetween the cutout and the turbo, that's for sure. And yeah, I'd definitely retune.

blackeg

yea, id retune. i have mine tuned at a lil less than 12:1 with my cutout open and with it closed (stock exhaust) im just about 11:1, so it varies up to about a full a/f point. with the cutout open im making a solid 30+more hp than with it closed, and consequently you will need more fuel to compensate

jdm'dc2sc61

i have the same setup with the cutout straight off the turbo and no bung for the o2. i haven't gotten my car tuned yet, will this make things more difficult to tune?

p.s. im not tryna jack the thread, i figured we're both in the same situation.

FONK

no,completly understanable,i need some answers,hehehe j/k,but how much boost you think i can run with it open i used to run around 17psi

blackeg

well with it open, everything elsse being the same you should make a few more psi right out of the box, just due to better flow

yee SERIOUS

iTrader: (1)

of course you need a retune. i bet your turbo is gonna spool wayyyyy faster. you want to go lean?

ExVtec

Tuning before and after having your cutout open may affect the tune.

Depends on many variables.

I have a 3" exhuast w/a cutout and w/it open it changes my a/fs from 10.9 to 11.4 in boost.

IF you have a stock exhuast and a cutout and are tuned with a stock or somewhat restrictive exhuast, the cutout will dramaticlly make a difference.

Always variables...depends on your application.

FONK

do think that 14 psi would be safe!!!!

Dc4turbo408

with 5 psi u will be super safe

lol, jk..

Naterror

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FONK &raquo;</TD></TR><TR><TD CLASS="quote">do think that 14 psi would be safe!!!!</TD></TR></TABLE>
I can tell you this far sure. Tuning it would be safer.

5thgen

I've just taken my exhaust off from the downpipe back. From a kteller/magnaflow 3" to just open 3" dp.

It may have changed my a/f by 2 tenths consistently....spool is much quicker though, was able to gain 4-5 psi (9-14psi) at 5000rpm....and a/f stayed where it was supposed to.