here is a list of the differences made to the engine for the new tC. What are the pro's and con's?

ENGINE — OUTLINE
ENGINE
EG-2
OUTLINE

MAJOR DIFFERENCES
The ’07 models have been modified from the ’06 models as follows:
Item Outline
Engine Specifications
[See page EG-5]
• Emission Regulations: ULEV (Ultra Low Emission Vehicle)
ULEV II
• Compression Ratio: 9.6 : 1
9.8 : 1
• Maximum Output: 119 kW (160 HP) @ 5700 rpm
120* kW (161* HP)
@ 6000 rpm
• Maximum Torque: 221 NVm (163 ftVlbf) @ 4000 rpm
220* NVm (162*
ftVlbf) @ 4000 rpm
Engine
ECM
[See page BE-67]
The ECM exchanges information via CAN (Controller Area Network).
Control
System Mass Air Flow Meter
[See page EG-14]
The intake air path of the mass airflow meter has been modified to enhance
detection precision.
Cylinder Head Cover
[See page EG-33]
The shape of the PCV (Positive Crankcase Ventilation) baffle plate has been
modified to enhance oil flow volume.
Cylinder Head
Gasket
[See page EG-35]
Along with modifying the engine coolant passage, the shape of the cylinder
head gasket has been modified.
Cylinder Block
[See page EG-36]
• Oil jets have been added to help cool the pistons.
• A water jacket spacer has been added to optimize temperature distribution
across the cylinder bore walls.
Engine
Mechanical
Piston
[See page EG-38]
• The thickness and tension of the top and 2nd piston rings have been
reduced in order to reduce friction.
• The shape of the pistons has been modified to change the compression
ratio.
Crankshaft
[See page EG-40]
The crankshaft bearing groove is deeper in the middle of the bearing than
at the ends. This enhances engine oil lubrication in the middle of the bearing.
Balance Shaft
[See page EG-41]
The balance ratio of the balance shafts has been enhanced to reduce noise.
Valve Mechanism
[See page EG-42]
• The profile of the intake camshaft has been modified to enhance output
by increasing the valve operation angle and valve lift.
• The exhaust valves are heat-treated to enhance thermal resistance.
• The diameter of the intake valve springs has been reduced to
accommodate increased valve lift, without changing the seat pressure.
Emission Control System
[See page EG-49]
The EVAP service port has been discontinued.
Intake
Throttle Body
[See page EG-62]
The throttle valve shaft of the throttle body has been flattened to increase the
size of the throttle valve opening.
Intake Manifold
[See page EG-63]
The length and shape of the intake manifold ports have been modified to
accommodate increased maximum engine speed.
*: Maximum output and torque rating is determined using the revised SAE J1349 procedure.
ENGINE — OUTLINE EG-3
Item Outline
Exhaust Exhaust Manifold
[See page EG-65]
• The shape of the exhaust manifold has been modified.
• The capacity, wall thickness, and noble metal catalyst specifications of
the TWC (Three-Way Catalytic converter) have been modified in order
to comply with ULEV II.
Oil Jet
[See page EG-37]
Piston-cooling oil jets have been added to enhance lubrication performance.
Lubrication
Oil Pan
[See page EG-70]
The capacity of the lower oil pan has been increased, and the shape of the
oil pan has been modified to reduce the energy consumed by the balance
shafts churning the engine oil.
Starter [See page EG-72] Starter Output: 1.6 kW
1.7 kW
Charging Generator Pulley
[See page EG-75]
A generator pulley with an integrated one-way clutch is used to reduce
friction.

One con (for people wanting to turbo or s/c) would be the higher compression. Yet, the oil cooling jets and the water jackets will help keep the temperatures down so the engine could handle a bit more power, or at least handle the power easier. Almost all of the rest seem like pro's, so I guess scion did some good changes. Anything else I didn't mention that is a big change?

 

glad to see they're making good improvement, I love my 2007 NB tC

 

so after all those improvements.. did it gain any horses?

 

yup....one horse gained...

although one lb of torque lost....

 

At first it is deceiving, but yes it did gain a decent amount of power.

Note
If you read up, the new HP and TQ ratings are measured on the testing procedure which is much more conservative. If you notice on the xA/xB, the engine did not change. However HP dropped from 108hp to 103hp. This is due to the new testing procedure, and it's fairly consistent across the board for Toyota. So the 1hp gain is really more like a 6-10hp gain. There's really no way to know for sure unless they are dyno'd on the same procedure and machine.

 

plus once you slap on some stickers and vinyl you will gain another 25 HP

 

that's only on the 06's though...

 

oooh my bad, I'm still living in the past.....I'm not familiar with the current sticker/horsepower ratio

 

I love my 07 BSP tC too! This makes me think what it will dyno at now... very curious compared to the others stock for stock. One reason it may not be 6-10 better is the new 3 cat header system, forgot what it was called exactly but I think it is more restrictive, now maybe header and exhaust will yeild a lil more power... why couldn't they just drop the comp. ratio to 9.0 and have it s/c from the factory for the same price, is that too much to ask??? haha j/p

 

.....or you could get a S/C Cobalt and have it fall apart on you in a few years........NOT j/k of course

 

cobalt, cavalier... same thing right?!? plus that thing is a tank! my friend has a black cobalt ss and I was curious so I checked his curb weight and it was 3800ish pounds! Thats 900+ pounds more than our car hmm....

 

New Sticker/Decal Performance Rating:
AEM = +5 HP
NOS = +25 HP
VTech = +30 HP
Bulletproof Gas Tank Cover = +20 to MPG

 

I think all they did was level out the torque at the high end. Made it so that it wouldn't drop so sharply. And if you know how Torque and HP work, this means that the HP is probably holding steady at 160ish HP from 5700 RPM all the way to red line. This is very good.

 

It wasn't about gaining horses, it was all about passing the all new 2007 emissions requirements.

 

it aint that restricted or low emissions my 07 still gets black on my exhuast tip.

 

seems like alot of changes for a 1hp gain and 1tq. lost.

 

DAMNIT, nobody can read. The testing methods for HP and tq have since changed. If you really read the post, you will see that. So the gain and lost isn't exactly accurate, as it is NOT an apples to apples comparison; they were tested using different methods.

 

Supposedly the 07s are a bit underrated in comparison to 05/06s.. Would love to see a dyno comparison between the models.

Most importantly the changes found in the 07s will extend the life and tolerances of the engine in the long run (given you don't drive the ____ out of your car all the time).

I still haven't found the reason why 07 RPMs float between gear changes versus the 05/06s.. some people say there might or is a dashpot on the 07s. Although I haven't driven another 07 to compare to mine, perhaps my 07 is jacked. Shrug. The powerband has been shifted closer to redline on the 07s, which means it should typically out-pace a 05/06 tC.

Jay

 

This is exactly right.. I drive my gf's 06 tc and obviously my 07 tC all the time.. my 07's torque curve is so flat, my car actually feels slower compared to her 06 that has it's torque ramping up fast and dropping fast at redline.. She refuses to have a spirited run against me so I have no idea if 07s are actually faster ;)

Jay

 

thank you for the breakdown! i was looking for these specifics. good info that their method of testing has changed too! would love to hear if anyone drove their stock '06 against an '07.