Hello, as you may know, I have been interested in turbocharging my automatic since the day I bought it. I feel that the automatic may have more potential than the manual because of its taller gears, torque converter, and ability to stay in the motor's powerband by itself. I have yet to prove this on my own, as I have just started collecting parts for my build.
To turbocharge an automatic, you will need a piggyback ECU like the speeduino to control fuel and spark while the stock ecu controls the shifting as seen in this thread Guide - Run your Mazdaspeed Protege on a Speeduino
Here is a quote from Chris with SpeedyEFI
"When you order your ECU from us, make sure to include in the notes that it's for a piggyback application and we will float the temp sensor inputs.
If you have specific questions about the install, please ask. The speeduino wiki and the forums have decent guides in how to setup a piggyback application, but I know there will be questions that pop up."
here is the wiring diagram for it to run in piggyback.
and the tuning files are provided here by the author Speeduino Tune Files - Google Drive
as for the turbo system, this thread shows all the parts necessary to complete the swap A Guide to Turbocharging your 2.0L FS
when it comes to the automatic transmission, I have been in contact with lentech automatics. even though they do not produce parts for our transmission anymore, they have been very helpful in identifying flaws in the stock automatic such as the plastic stator, the open differential, the weak 2-4 band, and the lack of cooling capacity. here is a quote from them on how to adress these issues
"The plastic stator is an internal component in the torque converter, so you'd replace the entire torque converter with an upgraded one that has that component upgraded to aluminum.
As for the differential, I visited the website and it does list a solution for the 4F27E
(update: do not buy the LSD. it looks to
be a continuation of the “phantom grip” company’s snake oil. Basically a crappy Detroit locker)
Regarding friction, it’s not just materials (specifically in the 3rd-4th (direct) clutch...its capacity. Some applications use single sided friction setup and others are traditional friction/steel plates alternating. Focus models typically have 3 friction and the steel plates between them are the same thickness as the top pressure plate. An easy upgrade is to order extra steel plates for the forward drum (which are the same pattern and fit into the direct drum too) and stack it like this: thick steel plate against the piston, then a friction, then thin steel plate, friction, thin steel plate, friction, thin steel plate, friction, thick top plate, snap ring. This upgrades it from 3 to 4 friction discs....a 33% increase....all with factory style parts.
Do the upgraded converter, add those extra frictions while doing a rebuild and add a cooler and it should live. Pressure could be added via the valve body, or if you have ECU access, it can be done via tuning as well. Good luck!"
since the stock ecu on this car has never been cracked, tuning the ecu is not an option.
a shift kit to raise line pressure and reduce friction is available here Trans Go SK4F27E: Valve Body Shift Kit 4F27E, FNR5, FN4A-EL, FS5A-EL - JEGS
aftermarket transmission cooler is here https://www.summitracing.com/parts/tci-820500
an electric fan may be necessary to keep the transmission cool in hot weather. Heat is the #1 killer of an automatic transmission
the stock rods should be able to support the power produced by 7 psi of boost. I would go with forged rods and pistons for anything over 190 crank horsepower
the block does not need attention as it was used in a turbo-diesel model overseas, which is where many of the parts for the mazdaspeed protege originated
the FSDE also suffers from oil starvation when the oil moves away from the pickup in the oil pan. An aftermarket baffle can be found here Pope Engineering Performance (PEP) Oil Pan Baffle for Mazda Protege
DO NOT PLUG THE OIL SQUIRTERS!!!! they are necessary for piston cooling especially if you run forged internals!
also, since the turbo will be taking the place of the manifold catalytic converer, you will either need to put another cat in front of the secondary or use a drilled-out spark plug non fouler on the o2 sensor to trick the system if you dont want a permanent CEL.
with all parts accounted for, the system will run around $3000 if you rebuild the transmission yourself which I would not recommend
a lot of other information on the mazda protege can be found here Protegé FAQ
I have yet to put all this information to use in my own vehicle. I will be turbocharging my car this summer and will update as I go. Furthermore, I am not responsible for damages to vehicles. do keep in mind I am a dumb 18 year old and my experience with these cars is middling at best
To turbocharge an automatic, you will need a piggyback ECU like the speeduino to control fuel and spark while the stock ecu controls the shifting as seen in this thread Guide - Run your Mazdaspeed Protege on a Speeduino
Here is a quote from Chris with SpeedyEFI
"When you order your ECU from us, make sure to include in the notes that it's for a piggyback application and we will float the temp sensor inputs.
If you have specific questions about the install, please ask. The speeduino wiki and the forums have decent guides in how to setup a piggyback application, but I know there will be questions that pop up."
and the tuning files are provided here by the author Speeduino Tune Files - Google Drive
as for the turbo system, this thread shows all the parts necessary to complete the swap A Guide to Turbocharging your 2.0L FS
when it comes to the automatic transmission, I have been in contact with lentech automatics. even though they do not produce parts for our transmission anymore, they have been very helpful in identifying flaws in the stock automatic such as the plastic stator, the open differential, the weak 2-4 band, and the lack of cooling capacity. here is a quote from them on how to adress these issues
"The plastic stator is an internal component in the torque converter, so you'd replace the entire torque converter with an upgraded one that has that component upgraded to aluminum.
As for the differential, I visited the website and it does list a solution for the 4F27E
(update: do not buy the LSD. it looks to
be a continuation of the “phantom grip” company’s snake oil. Basically a crappy Detroit locker)
Regarding friction, it’s not just materials (specifically in the 3rd-4th (direct) clutch...its capacity. Some applications use single sided friction setup and others are traditional friction/steel plates alternating. Focus models typically have 3 friction and the steel plates between them are the same thickness as the top pressure plate. An easy upgrade is to order extra steel plates for the forward drum (which are the same pattern and fit into the direct drum too) and stack it like this: thick steel plate against the piston, then a friction, then thin steel plate, friction, thin steel plate, friction, thin steel plate, friction, thick top plate, snap ring. This upgrades it from 3 to 4 friction discs....a 33% increase....all with factory style parts.
Do the upgraded converter, add those extra frictions while doing a rebuild and add a cooler and it should live. Pressure could be added via the valve body, or if you have ECU access, it can be done via tuning as well. Good luck!"
since the stock ecu on this car has never been cracked, tuning the ecu is not an option.
a shift kit to raise line pressure and reduce friction is available here Trans Go SK4F27E: Valve Body Shift Kit 4F27E, FNR5, FN4A-EL, FS5A-EL - JEGS
aftermarket transmission cooler is here https://www.summitracing.com/parts/tci-820500
an electric fan may be necessary to keep the transmission cool in hot weather. Heat is the #1 killer of an automatic transmission
the stock rods should be able to support the power produced by 7 psi of boost. I would go with forged rods and pistons for anything over 190 crank horsepower
the block does not need attention as it was used in a turbo-diesel model overseas, which is where many of the parts for the mazdaspeed protege originated
the FSDE also suffers from oil starvation when the oil moves away from the pickup in the oil pan. An aftermarket baffle can be found here Pope Engineering Performance (PEP) Oil Pan Baffle for Mazda Protege
DO NOT PLUG THE OIL SQUIRTERS!!!! they are necessary for piston cooling especially if you run forged internals!
also, since the turbo will be taking the place of the manifold catalytic converer, you will either need to put another cat in front of the secondary or use a drilled-out spark plug non fouler on the o2 sensor to trick the system if you dont want a permanent CEL.
with all parts accounted for, the system will run around $3000 if you rebuild the transmission yourself which I would not recommend
a lot of other information on the mazda protege can be found here Protegé FAQ
I have yet to put all this information to use in my own vehicle. I will be turbocharging my car this summer and will update as I go. Furthermore, I am not responsible for damages to vehicles. do keep in mind I am a dumb 18 year old and my experience with these cars is middling at best
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