How good does an E-cutout do for FI cars?
I have a gsr about to do my boost setup.
I was thinking of leaving my stock piping
and getting a 3" e cutout.

 

get a boost activated cutout

http://atpturbo.com/root/releases/release091004.htm

 

Any cutout is going to make power on an FI car versus having the backpressure of a full exhaust. Get the ecutout and activate it through management outputs, as well as use a manual override switch to use it full time if you wish.

If you get the boost activated one it could get annoying to hear it every time you get into boost at all. If you activate it through a programmable management output though you can determine parameters in which it'll open....much better.

 

Personally I LOVE the cutouts. I just finished my T4 GSR setup, Sleeper unit. Has stock muffler and exhaust, but 3" dp feeding a 3" cutout that is manual (i have to physically remove it to run it open) But on the street i love the looks i get with people thinking my car just has a HUGE exhaust leak....

 

Is it better to tune with the cutout or stock exhaust?

 

Tune with the cut-out open.

 

whats a cut out a 2 step or something completely diffrent

 

something completely different, it is essentually a butterfly much like your throttle body that opens up to let exhaust out fast instead of going through your whole system

 

A lot of people will say that having a e-cutout is just another thing to break. And you know what? They are right. They do break, just think about how hot those exhaust gas temps can get and how much vibration those e-cutouts see. I have a e-cutout and one day it just stopped working, its a good thing it broke closed because it is loud. Open downpipe without a e-cutout for some reason seems a lot quieter to me. Turned out the motor fell off the e-cutout and was just hanging around. I took my e-cutout apart by seperating everything and re-bolted the motor back up and it works like normal. Bolts came loose because of the vibration. My point is, if you get a e-cutout just make sure you're ready to fix it if it breaks. I have it connected to my stock exhaust, it is a big difference when its opened and closed. But it can save you from getting a loud exhaust ticket or hassled because you have a big shiny muffler and it's well worth it.

 

dont get that boost activated cutout. it will slow up your spool time. get an eletric cutout. but make sure u modify it before you install it. what i did with mine was JB weld the motor to the e-cutout flange so that it would not fall off (my 1st motor fell off) after i did that the motor never fell off again. exhaust cutouts make a hige differences. i just tuned my friends car last night. with the cutout closed the car made 300whp. cutout open the car made 394whp (boost did increase a few lbs with the cutout open though)

 

will there be much gains with a open cutout vs a full 3'' exhaust ?..on a 400whp setup?(tuned of course for the cutout open)

 

I doubt it

 

If you have a good free flowing 3" exhaust with no cat/restrictions and a good free flowing muffler there should be little to no difference between open/closed.

 

what if your tune on the open cutout, but when your driving around, and close the cutout, should that effect your tune....i mean if you have a switch for the cutout.

 

ok i have a stright 3'' all the way back to my stright threw muffler..so ill probly just leave it

 

I had a QTP ecutout and I liked how it worked. it was nice to be able to open it up when needed. Thing I did not like was the quality. for the amount of money it costs, it was really poorly made. First couple days I got it, the wires came loose and I had to open it up and re-solder it to the motor. few months later, the whole motor fell off somewhere leaving only the flange. It worked well, while it was there though. I kinda laughed at a buddy of mine when I drove by his house the other day and seen him under his 240sx, asked him what he was doing and he said he was rewiring his ecutout, I asked him if he had a QTP one, and he said yeah.

 

I haven't noticed any difference between AFR. AFR at closed during boost might be richer, but other then that cruise and part throttle are the same, according to my wideband.

 

wow, everyone hates on that boost activated cutout...good thing I never got one.

I had a full 2.5" piping, only hitting 250hp on my ls/v turbo, t3, 64 trim, stock motor, 7 psi.

 

Yes your a/f will change with having open exhaust compared to having an exhaust. Trust me, i blew a motor doing so.

 

I would get a tune with it closed..

 

Dont listen to this guy, hes a tard...if you get an ecut, tune it with it open.

The car makes more power with it open, which means it needs more fuel. If you tune with it shut, then when you open it you will run lean.

 

I'll be putting this to the test Saturday, unless I get hit by a bus or something. I'm doing a 3-pull dyno run at King this weekend, 1 pull closed, 2 pulls open. However I have mine rigged to switch to secondary fuel/ignition maps whenever the cutout opens. Manual or fully automatic when I choose.


http://www.youtube.com/watch?v=1_2RlSZoplw

FYI that's a 3" for the "b pipe", merging to a stock axle-back.

 

Listen to this guy. Your car will run lean with the cutout open and run rich with the stock exhaust. You need to get a tune for BOTH cutout open and closed or your just asking for a blown motor.