Engine mods - why bother?

[RallyYaris]

I have been interested in super/turbocharging a Yaris. However, I have read that the engine will not be able to handle any appreciable extra horsepower without internal mods. So why bother getting CAI, exhaust mods, etc. if it will only add up to about 5 hp increase? It seems it will cost a lot of money to get the Yaris into the 150 hp range.

I guess I need to decide whether or not I want fuel efficiency or power. I wish they would put a slightly larger engine that could handle a turbo.

[Idjiit]

Supercharging it up to around 130-140hp combined with chopping off a lot of weight (which would be pretty easy) should give you a pretty decent power-to-weight ratio. What sort of ratio were you looking for?

[RallyYaris]

140 hp would be great, but I would seriously worry about the reliability of the motor. Wouldn't you need to get stronger internals to keep up with the extra power?

[jcove]

Originally Posted by RallyYaris

140 hp would be great, but I would seriously worry about the reliability of the motor. Wouldn't you need to get stronger internals to keep up with the extra power?

Anything more and you would, but 140 should be fine from what I've been reading. Check out the thread on the Blitz.

[Sp33dY]

i KIND OF AGREE. Spend the cash on suspension if anything ..... if it cant go fast in a straight line, make it go fast in corners!

[birdy]

i think with this motor just get intake exhaust and header and be done with it and then get coilovers, sways and kick ass

[why?]

Any type of serious adding of power, like forced induction, will shorten engine life.

The choice is always between mpg or hp.

However, a new intake, a full exhaust system, lightened flywheel, etc, things that will free up hp by removing restrictions and weight should not shorten the life of the engine.

[AutoTech1]

Originally Posted by why?

Any type of serious adding of power, like forced induction, will shorten engine life.

The choice is always between mpg or hp.

However, a new intake, a full exhaust system, lightened flywheel, etc, things that will free up hp by removing restrictions and weight should not shorten the life of the engine.

You can about cut your engine life in half with forced induction... Maybe more. With the yaris, I wouldn't even think about forced induction, unless you have the money for internal upgrades.

I like the idea of less wieght. Less rotating mass on the crank. Decreasing wieght and rotating mass is about the best modification anyone can do for a car, and it is often over looked. It does not destroy the engine. If anything, getting lighter parts are just that. They are lighter, but weaker. You're better of breaking a flywheel than a few pistons or rods...

The yaris can be a very agile car if it's balanced the right way with modifications. In a car like this, I'd shave lbs, perform bolt ons and do whatever it takes to increase power without turbocharging/supercharging. I'd also correct the suspension and brakes. But I'd end up writing a good amt. There are many ways to gain power... Not only through forced induction or giggle juice (nitrous, alcohol, Co2 etc).

If I bought this car though, the best bet would probably be to machine the engine. Send it to a private shop. N/A modifications are always great. They are just costly as well. :-P I wish I could say more, but that's all I can think of off the top of my head, since it's only my first year of Auto Tech so I only know so much. :-)

But remember this. If you perform a good amount of N/A modifications, you may want to consider crossing over to Forced Induction afterwards... This gets crazy with explaining, but you have no clue how many ways you can get power from a car.

[Sp33dY]

Originally Posted by AutoTech1

If anything, getting lighter parts are just that. They are lighter, but weaker.

.....And it's only my first year of Auto Tech so I only know so much. :-)

Not necessarily true.
Keep studying .... you have a lot to learn .

[AutoTech1]

Originally Posted by Sp33dY

i KIND OF AGREE. Spend the cash on suspension if anything ..... if it cant go fast in a straight line, make it go fast in corners!

This car is good for that stuff too. Nice input. ;-)

[AutoTech1]

Originally Posted by Sp33dY

Not necessarily true.
Keep studying .... you have a lot to learn .

I'll place a bet saying lighter parts can be weaker. In most cases they are weaker... But where they are weaker, they are stronger somewhere else... Everything has it's advantages and disadvantages...

[Idjiit]

Originally Posted by AutoTech1

I'll place a bet saying lighter parts can be weaker. In most cases they are weaker... But where they are weaker, they are stronger somewhere else... Everything has it's advantages and disadvantages...

Of course lighter parts can be weaker. But usually aftermarket parts aren't. They're just made out of materials that are prohibitively expensive for a company like Toyota to put in a car that retails for $11,000. And of course some of these parts trade off performance for ultimate drivability.

[why?]

Lighter parts are not weaker. That would be stupid.

F1 parts are the lightest parts any vehicles use. They are also some of the strongest. F1 engines spin to 20,000 or so rpms.

It will cost more money, but it would be worth it. Every pound you can take out of a car means better gas mileage, handling, braking, acceleration, etc.

And the best thing is Yaris engines only make 106 hp. I bet it would be hard to find a part too weak to handle Yaris like power.

[AutoTech1]

Originally Posted by why?

Lighter parts are not weaker. That would be stupid.

F1 parts are the lightest parts any vehicles use. They are also some of the strongest. F1 engines spin to 20,000 or so rpms.

It will cost more money, but it would be worth it. Every pound you can take out of a car means better gas mileage, handling, braking, acceleration, etc.

And the best thing is Yaris engines only make 106 hp. I bet it would be hard to find a part too weak to handle Yaris like power.

Ok. Before you jump ahead, let me point out, which I might not have, that I did not say "All light parts are weaker." That statement would be completely false. When you are looking into many interior components within the block, and you are going in the direction of racing, you can't simply be paying more for parts when they are not any stronger. These parts will be stronger. And more often, they'll be forged over their stock counterparts proving your argument true. A lot of internal parts are built strong, because it's torque that deals a blow to anything in the block, which is why aftermarket parts are made stronger for the engine. And when you force more air into the engine, this increases torgue; that is, if you are adding the right amount of fuel to get the best stachiometric ratio for performance.

As for some other things, take a flywheel for example, it is not built in mind for as much of a strength purpose. It's basically to decrease rotating mass. And you may wonder why? Well, if you decrease rotational mass, you decrease resistance and you free up tiny amounts of horsepower. Consider this... You can rotate a crank from nascar with two fingers... Could you ever do that on a yaris or a stock car of any kind that is not dedicated to a race track? Probably not. Kind of like what N/A modifications aim to do. Now that's not to say, that they (flywheels) aren't stronger than stock counter parts. They most likely are. But these parts are made for lighter wieght purposes and you can still break them under a lot of stress/torque.

And take a drilled rotor for example, to prove me right. Drilled rotors do nothing for stopping purposes. They are drilled to reduce wieght. With these drilled holes, they make the rotor weaker... Which is why you have to ask yourself, why even bother getting drilled rotors for a street application? Many do it. Now that's not to say again, that they aren't stronger than stock components. Most often than not, they are... But they are still weak... And that's what I'm saying. Anything that aims for a lighter wieght purpose only, is going to be weak... "Torque fighting modifications" will be stronger though... But keep in mind, everything is only stronger to a certain point.

Which brings me to an interesting fact. Bolt grades. To get a point across, some bolts are built weaker on purpose. Take a lawn mower or a machine of comparible size with the same purpose. Let's say that your blade binds up. Some of these machines have weaker bolts connected to this blade, so that you break the bolt, and not the blades... In other words, break a small thing to protect a large investment. And for other applications you have stronger bolts... For the obvious fact that you don't want the bolts to break.

Any you're right. The Yaris can't break too many things yet with the torque it makes. It's not so much hp... But torque that kills an engine... I was talking about higher powered cars... But still, I wouldn't run forced induction on the Yaris, unless you consult a professional and get the right parts to rebuild an engine before doing so.

[AutoTech1]

Originally Posted by Idjiit

Of course lighter parts can be weaker. But usually aftermarket parts aren't. They're just made out of materials that are prohibitively expensive for a company like Toyota to put in a car that retails for $11,000. And of course some of these parts trade off performance for ultimate drivability.

Or they trade off drivability for performance. Or they trade off reliability for performance... Or they trade off life for performance and so on and so fourth. I have to agree with you. And that's what I was trying to say. Not all lighter parts are weaker. But some are. And some can be... But it depends on how you look at it. I can say, they are stronger and be right, or I can say they are weaker and be right... Depends no how you look at it. Everything has it's weakness and it's strength...

[C2AUTOSPL]

Market rightnow is very small for the Yaris. We'll see what the future holds.

[YarisHatch]

Its all about power to weight. On a 2,200lbs car, 110whp is going to produce acceleration much differently than a 3,000lbs car. People get too caught up on dyno numbers that they loose sight of what car those numbers are on.

Also, when boosting any original n/a motor, its always best to upgrade the internals no matter what psi you plan to run on in terms of daily. Because in the end, you'd rather over-build the motor/tranny than underbuild. At least, thats the way i think.

[Snake]

if you want any real power on the yaris, just drop in a 2zz (1.8) motor from a celica or
a 2AZ-FE 2.4 from a scion tc, the stock yaris motor is not really good past 170 crank hp on boost without heavy internal block work

if you guys look into it, these swaps should really not be that difficult and they are inexpensive enough to find at a junkyard, plenty of aftermarket turbo kits for both motors with the celicas and tc's running around