Car question: how to increase performance without forced induction?

To expand on this - Your engine runs on air, which it draws in from the air intake. An after market intake setup seeks to make it as easy as possible for the engine to draw the air it needs. The “cold air” aspect of these things is just marketing - whatever real gains from the colder air is going to be less than the error factor on a dynometer (the ramp with the rollers that you use to measure horsepower). SOME cars, notably certain versions of the old Mustang and the Mazdaspeed 3, and some other Ford products, often gained significant amounts of power from an upgraded air intake, because 1) They were performance-minded models that had engines which sucked up a lot of air and 2) The factor air intake setup was so poorly designed that it was choking off the air supply to the engine. In any case, you will only see a performance increase near the top of the RPM range, since that is where the engine needs a lot of air.

For a Scion with a 4 speed auto, I’d say it’s a waste of time/money. It’s very unlikely it will make any noticeable difference.

You could do this, I suppose, but it won’t be cheap (or if it is, it’s probably useless), and at the end of the day, you’re spending a lot of money for performance that you probably won’t even notice.

Actually, this is the exact opposite of my understanding - aftermarket performance “chips” typically advance ignition timing, to a point that is less safe than what the manufacturer would like, but still pretty safe. Again, some cars i.e. turbocharged cars, will have more to gain from this, as their ECUs will also control the turbocharger boost, and there are more parameters that the ECU can fiddle with. Fuel economy should be increased, at the cost of less tolerance for low octane fuel and propensity to knock. The ones that are perfectly safe probably won’t give you very much extra power. Again, a waste of time and money on a 4 speed auto economy car, IMO.

I’m not sure that the auto 'box makes as much of a difference as you and Tristan think it does - regardless of how long you hold a gear for, more power is more power.

It’s a 2.4L engine producing 160ish HP as standard; plenty of room there for improvement. Not everything has to be a 5.7L before it’s worth tinkering with.

Also, drop your seat down and back, only use one hand on the steering wheel, spin the tyres when starting off from traffic lights, it all helps boost power.

Channeling Colin Chapman, “Just add displacement” was going to be my original reply.

I don’t think any of use in this thread have a Scion Tc, look for some good forums. That’s where I learned about modding my Ford Contour and F-150.

These look good:

Actually, driving with one hand on the steering wheel lowers the suspension by 1.5". It doesn’t do anything for the performance, silly.

I gained a perceptible increase in performance on my Suzuki Aerio by installing an underdrive pulley.

50 Hp by changing the intake, exhaust and chip on a normally aspirated 2.4L motor?
Snerk… Giggle… Bwaaahaaaaaa.
Go ahead, pull the other one, it has bells on it.

FTR you cannot increase the power to any number with a chip. There is a limit, a very definite limit which is based on camshaft profile, port size in the head, and valve arrangement, and number. (Along with displacement of course) There is only so much air you can flow though a given size port. If you can’t flow more air, adding more fuel does not result in an increase in power.

I very seriously doubt that the engineers that designed that motor left 50 HP on the table. They might have, but I doubt it.

BTW since we are talking mods, here is a way to get 50 more HP from your car. More mods here

I got 178 HP (dyno tested) out of the 140HP-stock 2.2 four in a 1993 Accord, back when I was younger and much stupider. And that was with just a remapped chip and intake.

Unless you are using some type of new math 140+50 is substantially greater than 178.

I know the entire purpose of this thread is to offer you alternatives to FI, but in your case it probably makes the most sense. The TRD supercharger specially made for your tC and installed by your dealer will make a ton of difference. 200 hp at 6200 rpm, 184 lb-ft at 4200. A big bump in performance. A bit pricey (probably $3500-ish) but when installed by a Toyota dealership, you are covered by the factory warranty (3yrs, 36K miles I think?), and so you won’t have to worry about things that go wrong. I don’t think I would want to deal with the frustration and expense of a ton of NA bolt-ons that may give you only mild gains or, worse, decrease your performance.

The Scion tC is a natural for supercharging. Toyota says so. Listen to them. :slight_smile:

140 + 38 = 27%

160 + 50 = 31%

I didn’t go for the top-end chip available, I picked the second one down, which supposedly gave a smoother delivery. The exhaust I didn’t add might easily make up the difference, and in any case 4% is hardly “substantial”. Besides, I said 50HP would be the maximum increase, if you scroll up.

Hm. Well, if I had known that all the inexpensive minor mods were really only effective for manuals, I might have learned to drive a stick. :frowning:

sigh I wonder how much of a gas mileage hit I would take from supercharging, then. I need to do more research.

Based on this link:
It should not have an effect on your overall fuel economy (depending, of course, on how much you get on it). The link does mention the need to use premium instead of regular, though…

The problem with many inexpensive mods for NA motors is that they give you more power up top, sometimes sacrificing power in the low and mid range. With an auto, you are going really want to retain your mid range, since that is where you will be most of the time. With a manual, it is easier to wind it out more regularly.