1974 Rotary Swapped Corolla Hits The Dyno!

Summary

The video follows a group tuning and testing a Toyota Corolla with a Mazda rotary engine swap on a dynamometer. They start with a base tune and make modifications to improve drivability, facing challenges with exhaust backpressure limiting power. After multiple dyno pulls showing increasing horsepower figures up to 332 hp, they determine the current setup is at its limit without upgrading the turbo and exhaust. They decide to focus on reliability over more power for now, getting it ready for an upcoming road rally while managing expectations that the modified Corolla may not survive the event.

Takeaways

• 😀 They installed a new oil cooler from Amazon to fix the overheating issue with the Corolla
• 😮‍💨 There were some driveability issues with the tune which they worked to improve
• 🔥 The Corolla dyno tested at 332 horsepower but they limited it for durability
• 🚗 The goal is to get the Corolla running well enough to survive Sick Week
• 👨‍🔧 Mike helped tune the Corolla over the phone while shirtless
• 😂 There was some joking around about Mike's tattoos during the tuning process
• 😲 The dyno runs produced some big fireballs that got into the dyno room
• 🤔 They determined the turbo exhaust housing is too small causing backpressure issues
• 🛠️ They will swap the turbo exhaust housing before Sick Week for more power
• 👍 The driveability is much improved though it still needs some fine tuning

Q & A

What was the issue with the oil cooler that needed to be fixed?

The original oil cooler was failing and causing high oil temperatures, so Mike replaced it with a larger aftermarket oil cooler from Amazon to help keep temperatures under control.

What is the goal horsepower number they are shooting for on the dyno?

They are hoping to make around 400 horsepower on this dyno session.

Why are they only revving the engine to 7,000 RPM on the dyno?

Due to the tight exhaust housing on the turbo, there is too much backpressure building up at higher RPMs which causes the engine to break up and run poorly over 7,000 RPM.

What modification do they need to make to relieve the backpressure issue?

They need to install a larger exhaust housing on the turbocharger to flow more exhaust gases and reduce backpressure.

What is the peak horsepower number they reached on the dyno?

They managed to put down 332 horsepower at the wheels on their highest dyno pull.

Why did they stop doing dyno pulls at 332 horsepower?

They were running low on fuel due to doing many consecutive dyno pulls, and they also felt that more power would put too much stress on the stock rear end and transmission.

What event are they preparing the car for with this engine build?

They are getting the car ready for an event called Sick Week, which appears to be some type of road rally/track event.

Do they think the car will survive the Sick Week event in its current state?

They seem unsure if the car has enough drivability and durability modifications yet to reliably complete the Sick Week event.

What further improvements need to be made to prepare for Sick Week?

They still need to work on overall drivability, throttle response calibration, and making sure cooling system performance is adequate before the event.

What future modification do they mention to allow more power?

Swapping the motor and transmission at some point to handle increased power output.