‘07 Scion tC
HKS : Reloaded Intake PN# 70020-XT001
Tsudo : PN# N/A
DC Sports : PN# SHR-4402
Text, Photos, and Testing by Arnold Eugenio
Install by Arnold Eugenio and Brian Dawson

Now don’t go accusing us of going Scion crazy - we managed to throw in a Lexus, a Mazda, and a Chevrolet in this month’s tuning escapades. It’s just that we serendipitously happened upon a 2007 Scion tC (see also this month’s Tuner Test Drive) so the wheels started turning in our heads and we started testing.
Our main purpose was to see if the 2007 model year brought any changes to the lineup, aside from the obvious. As it turns out, we were playing R&D department for all of the manufacturers we contact, at least where ‘07 tCs are concerned.

Dyno Day
First up to bat in the ever popular I/H/E path was the HKS Super Mega Flow Reloaded intake system, released at SEMA 2006. Basically a redesign of their popular Super Mega Flow intake, the Reloaded system didn’t work on our 2007 model due to the different size of the MAF sensor (see picture at right.) By the time you read this, HKS should already be working on a replacement for it, as should most other manufacturers that have had a chance to R&D their intake systems on the ‘07 models. But, we couldn’t let a good baseline dyno go to waste - the car checked in at 141.1 WHP and 144.3 TQ - so we continued with the dynos for the day.

E is for Exhaust

Yes, the acronym is I/H/E but in the world of bolt-on performance, exhaust systems are usually purchased for a vehicle before the header is purchased. So, rather than destroy the natural order of things, we decided to try the Tsudo exhaust system first. Constructed of a stainless steel canister and piping that’s polished to a mirror finish, the entire system looked put together very well; the welds were clean and smooth and the flanges were flat. The system also included all necessary gaskets and bolts and lined up correctly, including all the facotry hangers. The system also came with a tip-mounted silencer to help quiet things down on the street. Our decibel meter was MIA during the test, but our “ear dynos” noted that the included silencer did quite the exhaust significantly enough to warrant two tests - one with and one without the silencer installed.
With the silencer, the exhaust system managed a 3.0 WHP and 1.6 lb/ft TQ increase at the max point, checking out at 144.1 WHP and 145.9 lb/ft TQ. However, in the interest of extracting the most horsepower, we decided to also test the exhaust system without the silencer.
With that in mind, a simple nut and bolt removal and we were back on the dyno. Sans silencer, the exhaust system turned out 147.2 WHP peak and 147.1 lb/ft TQ peak; there was a 5-7 WHP increase in the low to mid-low range, and another large jump after 5500rpm, spanning almost 7-9 WHP. In terms of peak horsepower gains, the exhaust alone (without the aid of an aftermarket intake) garnered an additioonal 6.17 WHP and 2.79 lb/ft TQ.

H is for Header

... and when we think of headers, DC Sports comes immediately to mind. Building their reputation in the Honda/Acura heyday of import drag racing, they have since expanded to include other popular sport compact applications, including the ever-popular Scion line. Since we ran across a glitch in the intake fitment, we were prepared to do more work than necessary (outside of DC Sports’ included instructions) to try to get the header to work. To our very pleasant surprise, the header was a direct bolt-in, with all the flanges and brackets where they were supposed to be. With that matter settled, we turned the wheels of the dyno and churned out 153.9 WHP and 151.2 lb/ft TQ at the peak output, good for an additional 6.6 additional peak WHP and 4.1 lb/ft additional peak TQ. The header showed an impressive 10-12 WHP gain at the extreme low-end and again from 4500 rpm to 6500 rpm.

Conclusion

So, 2007 tC owners, rejoice. We’ve shown you two options to complete the basic I/H/E combination, and we’re sure by the time you read this you’ll have more options to take care of the remanufactured (and therefore smaller) MAF sensor situation.
Should we come across another 2007 tC, or one of those tasty stripped-down Spec tC’s, we’ll be sure to throw some more bolt-on parts on it to see what we - and what you - can expect to find.