To boost/improve Yaris, or move on....?

[ROCKLANDTOYOTA]

Originally Posted by Jason@SportsCar

Only you know what will make you happy... But I would start with the basics and work up.

First, better suspension. Get a set of quality coil-overs. The Tokicos are not track worthy, they are an OK street shock - hint, stay away from any adjustable shock that combines compression and rebound adjustments, you will never get the damping curve where you want it. Stick with rebound adjustable shocks unless you really know what you are doing, you can really screw up a car playing with the compression settings.

Swaybars: if you get the springs and shocks right you wont need to bolt a 15lb weight to your rear axle.

Brakes: the stock brakes are overkill for the weight of the Yaris. Upgrade the front pads and leave the rest alone. If your car has a lot of miles, or the lines look suspect, get the stainless ones. We only added brake cooling ducts when we went to the 13" wheels because the airflow is so restricted, we have still never had fade - and this is with a 40min race, not a few hot laps.

Trans: this makes the car, you must get an LSD. If you have the money get the OS Giken, if you want to go cheaper get the TRD unit. BUT while you are in there install the xB 4.312 final drive, it really wakes the car up. You will already be paying the labor (or doing the work) to pull the stock gears when you install the LSD, it is not much more work to swap the gears.

Tires/wheels: 13" wheels make the car a rocket. They give you an even shorter final drive, lower the cg (and help get the roof down out of the air), they are also a lot lighter than the big stuff. Another advantage is you can run a wide 13" tire without it bashing the fenders, no need to cut or roll.

Bolt-ons: Get the header, intake and ecu. You can really unlock some power.

That alone should be enough to take out any stockish Cooper S. If you are not satisfied at that point you have all the basics covered, and now you add the FI.

As far as a radiator, the Mishimoto xB unit pretty much drops right in (you have to drill two holes in the core support), and we used the xB hose set.

what ECU are we to use for just BOLT-ONS???

[Jason@SportsCar]

Originally Posted by ROCKLANDTOYOTA

what ECU are we to use for just BOLT-ONS???

Anything that will let you past the rev limiter, and control the VVTi.

We had a custom harness made that allows us to piggy back an AEM EMS series 2.

There are other options out there, none of which are cheap. But without ECU control any mods, including FI, are compromised.

[Blown_xa]

Good advice was given for sure. If you go boost, keep it at a 40whp gain and no more if you want it reliable on a stock motor for track abuse. I say 40whp gain instead of a specific number because dynos vary. Get a baseline number, and use that same dyno later for reference. I popped rods many times at 150whp (our dyno) and it is never fun to invest $500 entry fee and go home on a tow truck. I must have done 6 Time Attacks at 130whp and never had issues. It was enough power to podium many times in street fwd, as long as you are a decent driver and you have everything else dialed in.

[OTB]

Originally Posted by Blown_xa

Good advice was given for sure. If you go boost, keep it at a 40whp gain and no more if you want it reliable on a stock motor for track abuse. I say 40whp gain instead of a specific number because dynos vary. Get a baseline number, and use that same dyno later for reference. I popped rods many times at 150whp (our dyno) and it is never fun to invest $500 entry fee and go home on a tow truck. I must have done 6 Time Attacks at 130whp and never had issues. It was enough power to podium many times in street fwd, as long as you are a decent driver and you have everything else dialed in.

thanks! I think alot of us wanted this info