James_GSC

so we had some time to play with and happened to have a couple of the Greddy tC axle backs in stock so we decided to do a little dyno shootout

Stock vs. No Exhaust vs. Greddy SP2 vs. Greddy Evo2

Test car is our in house project Scion tC - Bone Stock '06 model with 2200 miles on it running on 87 octane

From our measurements all the axle backs seem to have the exact same diameter piping - 60mm for the greddy units and measured 2.45" for the stock unit - kind of hard to measure with the flanges on them cause of the way they are mounted but simple piping designs and the flow of the mufflers can have a big difference.

Pics of the Exhausts:
all 3


evo2


sp2


stock


this first test is comparing the stock scion tC axle back vs running no axle back at all - surprisingly the car actually sound pretty good without the axle back installed and as you can see it did pick up quite a bit of power

002 - stock axle back
003 - no axle back


on went the Greddy Evo2 axle back - sounded good - pretty close to a stock sound more or less - just a bit deeper - john mentioned having a little issue with the driver side exhaust hanger - didn't really want to line up as well as it could of

002 - stock axle back
005 - greddy evo2 axle back


next came the greddy sp2 axle back - i was expecting to like the look of this one the best once it was on the car but slight fitment issues seemed to push the exhaust tip out a little further than i would of liked, the sound was quite nice - close to stock with a bit of a rumble to it

002 - stock axle back
007 greddy sp2 axle back


for comparison sake - this is the greddy evo2 vs the greddy sp2 - dyno graphs are pretty much identical

007 - greddy sp2 axle back
005 - greddy evo2 axle back


looking for other small modifications we could do with the car while we had it strapped down to the dyno we decided to remove the air filter all together and see what would happen - a nice little increase for something as simple as removing the filter and running it open

009 - greddy sp2 axle back with air filter removed
007 - greddy sp2 axle back


here is the graph of the stock axle back vs the greddy sp2 axle back with the air filter removed

002 - stock axle back
009 - greddy sp2 axle back with no air filter


here are all the graphs together - kind of hard to read but to show a little comparison - no matter how you put it removing the stock axle back and replacing it with an aftermarket unit will pick up a little increase all throughout the powerband without sacrificing power anywhere and keeping the tone quite reasonable

002 - stock axle back
003 - no axle back
005 - greddy evo2
007 - greddy sp2
009 - greddy sp2 with no air filter






Please let me know if you have any questions and I will answer them to the best of my ability. All pics and graphs can be seen here - http://gscdownloads.com/scion/exhaustdyno/

James@GSCMotorsports.com

matty-tC

1whp

w00t!

jager_kc

thanks for the info james, i was wondering how much louder is the axel back than stock? and how is the idle sound?

James_GSC

at idle you really can't even hear either exhaust - no louder than stock at all

as for at wide open throttle - if a stock exhaust was 1 on a scale of 1-10 - the greddy exhausts would be a 2 - not much louder at all

matty-tC

yeah add an alphawerks header to that lol

James_GSC

our header test will be coming up shortly - we just had some free time and some parts here

the header test will hopefully be done within 2 weeks

DTRUONG_112

Thanks for the numbers...I like it when people dyno different setups to see how much HP and TQ are gained.

matty-tC

Great work. You're combining the exhausts and header with that right? Or stock exhaust with different header designs?

James_GSC

we are leaving the sp2 on the car so the header testing will be done with that installed - and we would like to get our hands on a S pipe as well to test the headers with and without to get pretty comprehensive data

the evo2 that we used on the car for testing is for sale if anyone is interested - brand new out of the box - onto the car for 2 dyno pulls and back into the box

matty-tC

$?

James_GSC

$420 shipped

acasanova

Hey thanks for the tests guys 5.66hp peak 5tq not bad for just an axleback.

dmxsoulja3

BUMP FOR JAMES. The hatch is doing great

James_GSC

lol - good to hear - having fun with the tC over here now

should have some nice parts available for it soon that we are working on

acasanova

Cant wait for the Header or intake roundup.

05-RS1

how bout trd or injen? also i was pretty surprised that removing the stock axle will give u 5 whp and 4tq..i didnt know u can get that kind of power by removing the axle..actually i thought removing the muffler was jus for ricers who want some sound but dont wanna fork up the doe for an axle or catback

B1uEsC1uEs

nice info
ive been thinking about getting the evo2 since i got my car

franktherank

awww...shoulda done a TRD dyno as well...but great testing thats a lotta dynoing...

Whocares05050

thanks for the dynos, hope you all can get the header pulls ASAP, thanks

daewonder

nice dynos. thanks for the info!