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.

Outlines

00:00

😀 Installing a new oil cooler and preparing for dyno testing.

This paragraph discusses installing a new, cheaper oil cooler from Amazon to replace the damaged one and prevent overheating issues. It mentions talking to Mike more about the incident, getting the Corolla ready for dyno testing, and covering all bases to avoid issues at Sick Week.

05:01

🔥 Doing dyno pulls and reaching 266hp, but having backpressure issues.

This paragraph describes doing dyno pulls and reaching 266hp initially, but having issues with backpressure limiting power. It mentions revving only to 7000rpm due to the backpressure, the need for a larger exhaust housing, and optimizing drivability for now.

10:04

😱 Hitting 300hp but melting interior parts with fireballs.

This paragraph discusses pushing the dyno pulls to 300hp but having huge fireballs that melted interior parts. It talks about still having backpressure issues and the need for a larger exhaust housing to properly flow the rotary engine.

Keywords

💡Corolla

Corolla refers to the Toyota Corolla, which is the car that the video focuses on modifying and tuning on a dynamometer (dyno). The Corolla is an inexpensive, common economy car that the hosts modify to make faster and more powerful as a fun project and for the Sick Week driving event.

💡dyno

A dyno, short for dynamometer, is a machine used to measure the horsepower and torque output of an engine. The hosts use the dyno to tune and test modifications to the Corolla's engine, measuring the power gains from new parts like a turbocharger.

💡turbocharger

A turbocharger is a forced induction system that uses exhaust gases to spin a turbine and compressor to force more air into the engine, allowing more fuel to be burned and increasing power output. The hosts install a turbo on the Corolla's engine as a main modification.

💡tune

Tuning refers to programming the engine management system, modifying things like fueling and ignition timing to optimize performance. The hosts work with a tuner remotely to tune the turbocharged Corolla engine for maximum power and reliability.

💡back pressure

Back pressure refers to resistance or pressure opposing the engine's exhaust flow. The hosts identify back pressure issues limiting the turbocharged Corolla engine's performance, indicating the need for exhaust modifications.

💡Sick Week

Sick Week refers to a week-long driving event where cars compete on the street and track to test endurance and performance. The hosts aim to get the modified Corolla ready for the Sick Week event after completing dyno testing.

💡driveability

Driveability refers to how easy and smooth a car is to drive. The hosts tune the Corolla engine for good driveability before maximizing power, focusing on optimizing things like idle, acceleration, etc.

💡fuel map

The fuel map refers to the programmed fueling parameters in the engine management system that control how much fuel is injected based on operating conditions. The hosts tweak the Corolla's fuel map to optimize drivability and prevent leaning out under turbo boost.

💡ignition timing

Ignition timing refers to when the engine's spark plugs fire to initiate combustion. The hosts work with the tuner to optimize ignition timing along with fueling for maximum power and reliability with the turbocharger.

💡torque

Torque is a measure of rotational force produced by the engine, important for acceleration and towing. The dyno measures the Corolla engine's horsepower and torque output to evaluate modifications.

Highlights

Replacement of the oil cooler with a half-price option from Amazon to address overheating issues.

Selection of a slightly larger oil cooler to manage elevated oil temperatures.

Procurement of an additional oil cooler as a backup for an upcoming event, showcasing preparation and foresight.

Successful restoration of the car with good oil pressure, ready for dyno testing.

Goal to achieve 400 horsepower on the dyno to improve drivability and performance.

Collaboration with a remote tuner to adjust the vehicle's tune for better performance.

Initial dyno run resulting in 225 horsepower and 191 ft-lb of torque, indicating room for improvement.

Encounter with back pressure issues due to full exhaust system and tight exhaust housing.

Decision to overnight a larger exhaust housing to address back pressure and enhance performance.

Second dyno pull showing improvement to 266 horsepower after making adjustments.

Investigation into a persistent lean spot in the tune, affecting performance.

Further dyno testing leading to 292 horsepower, with significant back pressure still present.

Achievement of 300 horsepower on a subsequent pull after exhaust modifications.

Final dyno run reaching 332 horsepower but limited by fuel pressure, indicating a fuel system limitation.

Conclusion with 330 horsepower at 11 lb of boost, deemed sufficient for the vehicle's current setup.

Plans for future upgrades to fully utilize the engine's capabilities while focusing on reliability for an upcoming event.

Transcripts

[Applause]

well luckily Amazon had oil coolers

ready to go yeah made it real easy got

the same half price China One which is

obviously identical just without a big

fancy logo on it and uh this one should

do the trick so I don't think it hurt

the motor or anything I talked to Mike a

little bit more after that whole

incident and uh yeah next D got this one

from Amazon and should do the trick for

us yeah and it's a little bigger so yeah

a little bigger I noed the oil temps

were getting a little bit hot so I

figured it could fit a little bit bigger

one might as well and then I Al also

ordered another one just to have a

backup for sick week so never know but

trying to cover all our bases for this

week yep got her top back off with oil

fired it up sounds good oil pressure is

good so yep all away so we'll take it to

the dino tomorrow see what it

does

[Music]

[Music]

big Dino day for the Cora yeah man we'll

see what it makes we're probably going

to shoot like 400 hopefully keep this

reaction alive and get it to where it's

drivable cuz right now it is really

not easy on those ratchet straps back

there yeah we might tear the car apart

man hel together with a whole lot all

right guys we got the Corolla on the dyo

we are over here at Full Throttle Fab

and repair like always got her strapped

down and right now why is kind of going

over the tune and we are on the phone

with the Dorito boy himself he's at home

shirtless right now helping us out over

the phone there he is and uh bad boy I

got

[Laughter]

tattoos but uh we're starting with the

sidekicks base tune to kind of build off

of and uh kind of go from there so made

some changes going to try to work on the

driveability first probably and then

from there on do some power pulls and

see what it does that's the plan and not

blow it up and not blow it up that's key

I mean to be fair man I I tune the

sidekick on the street in front of

Crystal so is that why it run so bad it

a't it ain't blown up yet you going to

sick week Mike yeah if it doesn't if my

truck doesn't blow up tomorrow we're

going to see you guys there nice perfect

we'll see you

[Music]

[Music]

there

so wife has been doing a little

driveability making sure that it is

running good we're about to calibrate

the dyno and then do some power pools

and see what she

[Music]

[Applause]

makes first shake down hit on the dyno

it did 225 at 191 ft-lb of torque out of

the Dorito box yep so I've been playing

hell with it this morning just trying to

get kind of the fuel map where we need

it so it doesn't go lean all weird and

uh got that kind of sorted and then I've

been talking to Mike and the problem is

with the full exhaust 3-in exhaust and

the really tight exhaust housing we're

running into a lot of back pressure

issues so I'm not sure we're going to be

able to make a whole lot more power

right now because we're at 5 lb of boost

but 8 lb of dry pressure so it's more

than 1 to one which is really not ideal

and that's why I'm also only revving it

to about 7,000 RPM right now because

anything above that it just wants to

break up because of the extra back

pressure um so what I'm going to try and

do is overnight a larger exhaust housing

for this Turbo from VSS racing so we can

hopefully have that for a sick week and

make more power but uh for right now

we're just going to work on getting this

thing cleaned up a little bit get the

driveability a little more dialed in and

then go from there but uh couple little

issues we got to get figured out but

it's starting to make some progress we

might try and turn it up a little bit

more see if it'll do some more power but

uh definitely needs a bigger exhaust

housing on that turbo for sure getting

ready to go for pool number

[Music]

two that was a big old

Fireball

that one was

266 it it sounded or it felt better the

Boost definitely picked up looks like

you had a little breaking up going into

the pool there yeah I don't know what's

up with it it's just got this super

finicky lean spot what you think about

this

W whatever it ain't me doing it I don't

care cardo's up under here pulling our

exhaust off cuz we have a little bit of

a back pressure issue and we want to see

if the exhaust is contrib want to see

any of it I know why it's doing it but

why I went to the bathroom will not take

what I said for an answer so here we are

you think that'd be enough light I don't

know I Ain crawling my ass down there

yeah that' probably be

enough he's loud

[Music]

now

[Music]

292 on that one Jesus did that fireball

come up inside here all up in this holy

ridiculous damn what happened here

well I guess see how much boost that was

in if the back pressure got any better

that's more the question is the back

pressure versus the Boost the Boost is

we can always make more boost but you

got to fight the back pressure first it

revved out a lot further I'll tell you

that we still dropped to 7 lbs at the

end and web of boost we still got 12 lb

of dry pressure it it made more boost it

carried the Boost out further and didn't

drop as bad but it still made the same

back pressure so this turbine housing is

just way too tight and uh that's where

we're at with it that was

AAR that some was all up in here I

was about ready to grab a fire ex I know

I was about ready to kill it I was like

put the flame out all right guys we got

the exhaust back on going for another

pull

[Music]

here

300 we hit 300 nice not bad 8 lb yeah I

made 8 lb out the top on that one like

11 lb down low um but you can see here

in the

log as we as we're increasing RPM our

boost is tapering off and our back

pressure is coming up so green line down

here is back pressure red line is Boost

and yeah that's not good how much the

back pressure keeps climbing as the

Boost continues to drop off y so

definitely need a bigger exhaust housing

on this thing yep I think that'll take

care of a lot of our problems rotaries

flow a lot of air yeah so tried to size

it to have like a good responding Street

setup but just need to go a little

bigger yeah yeah a little bigger I think

it' be pretty good help on this thing

turned her up what 10 more

per. try it one more

time yeah we're going to give her a shot

see what it

does and

uh probably be the last pull just it was

just cool to put up a number but really

I'm going to turn it back down so that

it runs efficiently and you don't break

that rear end yeah that's going to be

the next thing that's going to let go

for

[Music]

sure

332 we might be out of

fuel I got a low fuel pressure light

that time so 32 yeah not bad starting to

pick up yeah we haven't put gas in it

all day yeah we've been doing pull after

pole with no gas so I think we uh

finally just ran her a l low so

hopefully she didn't get too lean there

well we're calling it there 330

horsepower at 11 lb of boost yep is what

it is yeah just making a little too much

back pressure but right it's plenty of

power for this rear end anyways so yeah

yeah it's going to destroy this thing if

we're done with it and uh later on in

the future obviously we're going to swap

it motor's capable of more power so

that's all in the future but right now

the key is to get it through sick week

and I'm still unsure if it's going to do

that so we need to focus on that right

now and uh making more power is kind of

the least of our worries so that's where

we're going to leave it we'll call it a

win though shot some sick Fireballs made

300 plus now he just got yep burnt some

of his leg hairs just got to make sure

the cooling Situation's good and figured

out and should just about be ready to go

yeah should be we'll know uh for sure

here in about 2 three days yep it's

coming up yep going to ride or it

ain't

it's driving way better now oh yeah not

bucking and banging nearly as bad yeah

it still definitely needs a little bit

but it's nothing he's somewhat drivable

now which is really

[Music]

nice

oh started to break them loose a little

bit yeah she started to SP this thing's

going to be so sketchy

bro but at least it's driving it's

somewhat drivable it still needs a

little bit of a pickup fix right as it's

coming into boost but definitely a lot

better than it

[Applause]

[Music]

was

[Music]

oh