My NA to Tii JDM Swap!!!
02-16-07, 06:00 PM
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rottary89
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My NA to Tii JDM Swap!!!
Project: 1989 Mazda Rx7 GTU(manual) into S5 JDM Turbo II with N/A wiring harness!!!
Before buying the engine and other parts I decided to do the following:
- Upgrade the break rotors with Brembo rotors and semi-metallic break pads (popular ones used in autoX). Also put the Turbo II calipers in the back to fit vented breaks, also better if you like to drift and e-break a lot =)
- Also bought the Turbo II carbon fiber hood because I decided to use the top mount for at least a year after the swap.
- some 17x7” ebay rims that looked good but sucked with 215/40/17 Falken GR Beta FK4 in the front and 225/45/17 Falken GR Beta FK4 in the back.
- Tein Flex Damper Suspension (idea was to make the car break better and handle better before the swap and have it prepared for more power, or at least power potential)
- Bought a Walbro 255 and installed it and ran the car for a few months to make sure the fuel pump is good.
- Installed a Autometer boost guage and narrow band A/F guage to a vacuum line and to the stock O2 sensor to make sure I get that does before the swap.
- I already had 2.5” full straight exhaust with only a hi-flow racing cat and a Apex’I N1 muffler.
Buying parts before the engine: (I just wanted to do a stock swap(and did NOT want to pass 10psi @ peak boost), with a B.O.V. for the sound… and of course I don’t care if people say that you don’t need a blow off valve, that’s their opinions, and also I knew I wasn’t going to run stock exhaust(I decided to keep mine since it was 2.5” already), S5 LSD as well)
-Mazdatrix competition engine and transmission mounts
-2 sets of new spark plugs from the dealer
-20W-50 Royal Purple, and a bunch of Penzoil 10W-30
-Radiator fluid
-Break fluid
-RacingBeat 2.5” dp with gasket, and two more regular exhaust gaskets
-used S5 Tii LSD
-used turbo axles
-new turbo driveshaft
-turbo throttle cable
-N370 pressure sensor
-N374 ECU (was bad, later explained)
-N370 ECU (was good)
-new oxygen sensor
-new thermostat
-Cosmo RE afm(same as S5 Tii afm)
-HKS ssqv kit
-top intake manifold gasket(x2, bought them after swap)
-89-91 FCD
- some EBay 3” intake (piping with filter, HKS look-a-like)
-new oil filter(x3), new fuel filter
-state 2 clutch & pressure plate with pilot bearing, other bearing
-other small stuff (like exhaust heat wrap, etc)
-turbo clutch slave cylinder came with the engine
Buying the engine:
- Bought the first engine from EBay: complete engine block with ECU (when we got it, and removed the exhaust manifold we realized that the engine was full of coolant(moisture, orange color, rust), and EVERYTHING inside was rusted including rotors and combustion chambers… I WAS SO HAPPY with this new findings… that I went into a one month long negotiation of getting my ******* money back ASAP… and after over a month I did get it back!)
- Bought the second engine from: https://www.tigerjapanese.com/index.php (they said they actually look at the engine before they ship ‘em to you LOL, so I gave it another shot) (this engine did not come with the ECU or afm, so I bought those separately)
Engine comes in!!!
1. First, we check the spark pulgs… no orange… no misture….
2. Then we took the exhaust manifold off and looked inside the cambers… looked GOOD! =)
3. Then I removed the A/C and powersteering… which I never had and I didn’t want to have now either.
4. We put ATF and flooded the engine with it, let it sit for a day or two then slowly started turning the engine(fan of course had to be removed).
5. After the engine turned smooth, we realized that there are only 5 good puffs instead of 6 when turning the engine… realizing that one of the side seals was stuck due to carbon build-up, so we put more ATF… with no results… then we put some Marvel Mystery Oil, and in about 30min, the seal got unstuck, and we had 6 strong puffs on each face of the rotors.
6. I took the intercooler, top intake manifold off
7. Removed the harness by numbering each sensor with plug by the same number, we also removed the transmission
8. Removed the old clutch, sent the flywheel to get resurfaced… got it back replaced both bearings (throw-out and pilot), put new clutch in, then put transmission back in.
9. I cleaned the whole engine, put the exhaust manifold and turbo back on the engine. We checked all the lines for being cracked and made sure the engine had everything on it.
10. Replaced the engine and transmission mounts.
11. You don’t have to, but I also removed the oil pan and made sure we got out most of the ATF and other crap, and then replaced the oil pan gasket, and put it back on
12. Put downpipe on after wrapping it in heatwrap. (extra: remove shifter from transmission and wait to put it back in from inside the car after new engine and transmission are already in!)
Swap time (total duration was 2 days, 28hours total, two people, one garage)
But first, some links that I used from rx7Club that helped me a lot in doing this swap (and having the Rx7 Hanes manual helps A LOT!!!):
https://www.rx7club.com/sitemap/t-26647.html
https://www.rx7club.com/showthread.p...light=jdm+swap
https://www.rx7club.com/showthread.p...=duty+solenoid
https://www.rx7club.com/forum/showthread.php?t=530860
https://www.rx7club.com/showthread.p...49#post6277949
I’m not going to go into too much detail of the mechanical side of the swap, because this is something that is pretty obvious and easy to do. I will explain tho all my problems, and what you NEED to do to make this work, which I know people would like to hear.
a. Replace N350 sensor with N370 pressure sensor (also plug in FCD)
b. Replace ECU located under passenger seat with the turbo one (N374 in my case… or N370 later).
c. Replace the fuel filter with a new one if you have to. Also your fuel pump if you have not done so prior to the swap like myself.
d. Install boost gauge and other gauges you wish as well.
e. Put new oil filter and spark plugs on the turbo engine
f. Replace throttle cable
g. Removed the top manifolds of the old engine still inside the car, and start unplugging every plug from the NA harness from its sensor.. and make sure that the numbers on the turbo engine match the numbers on your NA harness, so when you plug the NA harness onto the turbo engine is as easy at matching #7 plug with #7 sensor hehe. The only two exceptions are:
- Turbo Duty solenoid plug from the turbo harness needs to be spliced into the wires from the NA harness that went to the plug from the 6-port induction solenoid. (ECU pin: 3R)
- Knock sensor plug from the turbo harness needs to be spliced into the one thicker black/white wire from the NA harness that went to the plug from the VDI control solenoid. (ECU pin: 2M)
Take hood off, remove radiator.. bla bla bla, do what you have to do to safely removed engine transmission, driveshaft, diff, axles…
PUT NEW ENINGE WITH TRANSMISSION IN!!!
- After you get it in, start pluging in the N/A wiring harness on the turbo engine. Everything should go right in, there will be few plugs that will not have anything to connect with if you don’t have certain options on your car, and also remember that the JDM engine does not have AWS system.
- Also for the 5th gear/ neutral switch you only need to hook up the reverse light, because the JDM transmission does not have a 4pin connection, only 2 pin since they do not use the 5th gear switch!
- Make sure you have the injectors the right way, and the right angle and don’t crush one of the primaries by accident like me lol
- Replace the top manifold gasket if you wish , then put the manifold back on, then intercooler
- Put everything back on.. oil lines, blab la bla… if you have done the splice on knock sensor and duty solenoid this should just be an easy plug-n-play.
- Now, make sure your air pump is not rusted stuck like mine was (I guess that’s better then a rusted engine… LOL), and go into more problems by buying a used US air pump which are much bigger and use different brackets which are different then the US NA and JDM Turbo air pump brackets. Unless you decided to remove emission as well, but my rx7 is still a DD and I need to pass emission this July =( . I eventually got a used JDM air pump and found a custom length belt which works with it because the US belts are too long. If you run the car for a week or two like I did w/o air pump, power steering, a/c, only the alternator belt, you will snap that belt at least twice a week! Anyways, back to the swap:
- Connect all the wires to the transmission and starter
- Put radiator back in
- Your intake piping with air filter and afm connected
- The two hoses coming from the turbo duty solenoid and oil cap breather can get plugged back into the intake system before the turbo but after the afm
- Install the blow off valve if you wish
- THE LINES FOR THE FUEL GO BACKWORDS (JDM engine)
- Plug in oil lines, coolant lines, vacuum lines, b.o.v. lines, boost gauge lines, break booster line, and if you have power steering and a/c, then those too!
- Fan shroud back on, then fan
- Replace LSD and axles whenever you feel like it, then connect driveshaft back in.
- In my case, I made my 2.5” exhaust reach the new downpipe with some welding and new flange
- Put shifter inside car
- Put new oil in, clutch fluid, coolant, trans oil, LSD oil…
- I’m not sure if I forgot anything else major, but the car is ready to start… (put hood back on, or not)
In MY case: took over 10min of turning the car to start it. With many break in-between to not burn the starter or drain the battery.
When it did finally start…well... it didn’t sound right even though you could rev it fine and did idle good. I took it for a slow test drive, and it felt like it had NO power. I went back and did an immediate oil change to make sure no ATF or other crap is still in the engine. (FYI: We originally started the car on the old spark plugs which we have cleaned). After the first oil change and new plugs, we decided to call it a night at 4am and figure things out in the morning. (Next day after driving the car a little more, we looked the the new plugs and realized that the rear plugs were brand new; coming to the conclusion that the rear rotor was not combusting due to lack or fuel). The next day we put on the N351 ECU and the car drove perfectly (with a high idle)… and that’s how we knew the N374 ECU was bad, which seems like a very common problem. [For the rear rotor not combusting: we did additional test like injector resistance check, and pulsation, and spark and coils were tested as well]
I drove the car for about a week on the N351 ECU, without being hard on it (clutch had a 750mile break in period, and your supposed to be nice on engines that haven’t run in God knows how long). I got a used N370 ECU and put it in, then the car ran even smother, and eventually I got another JDM air pump and my alternator belts stopped snapping. I have 9.5psi peak boost with ~7psi @ redline. I did two more oil changes and a final one after I put on 800 miles since the swap, where I changed to 20W-50 Royal Purple, and new stock spark plugs (and of course new oil filter haha).
I would like to THANK everyone who has helped me on this forum with my questions, and made this swap possible and a success =) . And if anyone has question about this swap feel free to ask me, and I’ll be happy to help as much as I can!
There’s a picture before after the swap without an air pump: (and more pictures can be seen at www.myspace.com/13brotary)
Before buying the engine and other parts I decided to do the following:
- Upgrade the break rotors with Brembo rotors and semi-metallic break pads (popular ones used in autoX). Also put the Turbo II calipers in the back to fit vented breaks, also better if you like to drift and e-break a lot =)
- Also bought the Turbo II carbon fiber hood because I decided to use the top mount for at least a year after the swap.
- some 17x7” ebay rims that looked good but sucked with 215/40/17 Falken GR Beta FK4 in the front and 225/45/17 Falken GR Beta FK4 in the back.
- Tein Flex Damper Suspension (idea was to make the car break better and handle better before the swap and have it prepared for more power, or at least power potential)
- Bought a Walbro 255 and installed it and ran the car for a few months to make sure the fuel pump is good.
- Installed a Autometer boost guage and narrow band A/F guage to a vacuum line and to the stock O2 sensor to make sure I get that does before the swap.
- I already had 2.5” full straight exhaust with only a hi-flow racing cat and a Apex’I N1 muffler.
Buying parts before the engine: (I just wanted to do a stock swap(and did NOT want to pass 10psi @ peak boost), with a B.O.V. for the sound… and of course I don’t care if people say that you don’t need a blow off valve, that’s their opinions, and also I knew I wasn’t going to run stock exhaust(I decided to keep mine since it was 2.5” already), S5 LSD as well)
-Mazdatrix competition engine and transmission mounts
-2 sets of new spark plugs from the dealer
-20W-50 Royal Purple, and a bunch of Penzoil 10W-30
-Radiator fluid
-Break fluid
-RacingBeat 2.5” dp with gasket, and two more regular exhaust gaskets
-used S5 Tii LSD
-used turbo axles
-new turbo driveshaft
-turbo throttle cable
-N370 pressure sensor
-N374 ECU (was bad, later explained)
-N370 ECU (was good)
-new oxygen sensor
-new thermostat
-Cosmo RE afm(same as S5 Tii afm)
-HKS ssqv kit
-top intake manifold gasket(x2, bought them after swap)
-89-91 FCD
- some EBay 3” intake (piping with filter, HKS look-a-like)
-new oil filter(x3), new fuel filter
-state 2 clutch & pressure plate with pilot bearing, other bearing
-other small stuff (like exhaust heat wrap, etc)
-turbo clutch slave cylinder came with the engine
Buying the engine:
- Bought the first engine from EBay: complete engine block with ECU (when we got it, and removed the exhaust manifold we realized that the engine was full of coolant(moisture, orange color, rust), and EVERYTHING inside was rusted including rotors and combustion chambers… I WAS SO HAPPY with this new findings… that I went into a one month long negotiation of getting my ******* money back ASAP… and after over a month I did get it back!)
- Bought the second engine from: https://www.tigerjapanese.com/index.php (they said they actually look at the engine before they ship ‘em to you LOL, so I gave it another shot) (this engine did not come with the ECU or afm, so I bought those separately)
Engine comes in!!!
1. First, we check the spark pulgs… no orange… no misture….
2. Then we took the exhaust manifold off and looked inside the cambers… looked GOOD! =)
3. Then I removed the A/C and powersteering… which I never had and I didn’t want to have now either.
4. We put ATF and flooded the engine with it, let it sit for a day or two then slowly started turning the engine(fan of course had to be removed).
5. After the engine turned smooth, we realized that there are only 5 good puffs instead of 6 when turning the engine… realizing that one of the side seals was stuck due to carbon build-up, so we put more ATF… with no results… then we put some Marvel Mystery Oil, and in about 30min, the seal got unstuck, and we had 6 strong puffs on each face of the rotors.
6. I took the intercooler, top intake manifold off
7. Removed the harness by numbering each sensor with plug by the same number, we also removed the transmission
8. Removed the old clutch, sent the flywheel to get resurfaced… got it back replaced both bearings (throw-out and pilot), put new clutch in, then put transmission back in.
9. I cleaned the whole engine, put the exhaust manifold and turbo back on the engine. We checked all the lines for being cracked and made sure the engine had everything on it.
10. Replaced the engine and transmission mounts.
11. You don’t have to, but I also removed the oil pan and made sure we got out most of the ATF and other crap, and then replaced the oil pan gasket, and put it back on
12. Put downpipe on after wrapping it in heatwrap. (extra: remove shifter from transmission and wait to put it back in from inside the car after new engine and transmission are already in!)
Swap time (total duration was 2 days, 28hours total, two people, one garage)
But first, some links that I used from rx7Club that helped me a lot in doing this swap (and having the Rx7 Hanes manual helps A LOT!!!):
https://www.rx7club.com/sitemap/t-26647.html
https://www.rx7club.com/showthread.p...light=jdm+swap
https://www.rx7club.com/showthread.p...=duty+solenoid
https://www.rx7club.com/forum/showthread.php?t=530860
https://www.rx7club.com/showthread.p...49#post6277949
I’m not going to go into too much detail of the mechanical side of the swap, because this is something that is pretty obvious and easy to do. I will explain tho all my problems, and what you NEED to do to make this work, which I know people would like to hear.
a. Replace N350 sensor with N370 pressure sensor (also plug in FCD)
b. Replace ECU located under passenger seat with the turbo one (N374 in my case… or N370 later).
c. Replace the fuel filter with a new one if you have to. Also your fuel pump if you have not done so prior to the swap like myself.
d. Install boost gauge and other gauges you wish as well.
e. Put new oil filter and spark plugs on the turbo engine
f. Replace throttle cable
g. Removed the top manifolds of the old engine still inside the car, and start unplugging every plug from the NA harness from its sensor.. and make sure that the numbers on the turbo engine match the numbers on your NA harness, so when you plug the NA harness onto the turbo engine is as easy at matching #7 plug with #7 sensor hehe. The only two exceptions are:
- Turbo Duty solenoid plug from the turbo harness needs to be spliced into the wires from the NA harness that went to the plug from the 6-port induction solenoid. (ECU pin: 3R)
- Knock sensor plug from the turbo harness needs to be spliced into the one thicker black/white wire from the NA harness that went to the plug from the VDI control solenoid. (ECU pin: 2M)
Take hood off, remove radiator.. bla bla bla, do what you have to do to safely removed engine transmission, driveshaft, diff, axles…
PUT NEW ENINGE WITH TRANSMISSION IN!!!
- After you get it in, start pluging in the N/A wiring harness on the turbo engine. Everything should go right in, there will be few plugs that will not have anything to connect with if you don’t have certain options on your car, and also remember that the JDM engine does not have AWS system.
- Also for the 5th gear/ neutral switch you only need to hook up the reverse light, because the JDM transmission does not have a 4pin connection, only 2 pin since they do not use the 5th gear switch!
- Make sure you have the injectors the right way, and the right angle and don’t crush one of the primaries by accident like me lol
- Replace the top manifold gasket if you wish , then put the manifold back on, then intercooler
- Put everything back on.. oil lines, blab la bla… if you have done the splice on knock sensor and duty solenoid this should just be an easy plug-n-play.
- Now, make sure your air pump is not rusted stuck like mine was (I guess that’s better then a rusted engine… LOL), and go into more problems by buying a used US air pump which are much bigger and use different brackets which are different then the US NA and JDM Turbo air pump brackets. Unless you decided to remove emission as well, but my rx7 is still a DD and I need to pass emission this July =( . I eventually got a used JDM air pump and found a custom length belt which works with it because the US belts are too long. If you run the car for a week or two like I did w/o air pump, power steering, a/c, only the alternator belt, you will snap that belt at least twice a week! Anyways, back to the swap:
- Connect all the wires to the transmission and starter
- Put radiator back in
- Your intake piping with air filter and afm connected
- The two hoses coming from the turbo duty solenoid and oil cap breather can get plugged back into the intake system before the turbo but after the afm
- Install the blow off valve if you wish
- THE LINES FOR THE FUEL GO BACKWORDS (JDM engine)
- Plug in oil lines, coolant lines, vacuum lines, b.o.v. lines, boost gauge lines, break booster line, and if you have power steering and a/c, then those too!
- Fan shroud back on, then fan
- Replace LSD and axles whenever you feel like it, then connect driveshaft back in.
- In my case, I made my 2.5” exhaust reach the new downpipe with some welding and new flange
- Put shifter inside car
- Put new oil in, clutch fluid, coolant, trans oil, LSD oil…
- I’m not sure if I forgot anything else major, but the car is ready to start… (put hood back on, or not)
In MY case: took over 10min of turning the car to start it. With many break in-between to not burn the starter or drain the battery.
When it did finally start…well... it didn’t sound right even though you could rev it fine and did idle good. I took it for a slow test drive, and it felt like it had NO power. I went back and did an immediate oil change to make sure no ATF or other crap is still in the engine. (FYI: We originally started the car on the old spark plugs which we have cleaned). After the first oil change and new plugs, we decided to call it a night at 4am and figure things out in the morning. (Next day after driving the car a little more, we looked the the new plugs and realized that the rear plugs were brand new; coming to the conclusion that the rear rotor was not combusting due to lack or fuel). The next day we put on the N351 ECU and the car drove perfectly (with a high idle)… and that’s how we knew the N374 ECU was bad, which seems like a very common problem. [For the rear rotor not combusting: we did additional test like injector resistance check, and pulsation, and spark and coils were tested as well]
I drove the car for about a week on the N351 ECU, without being hard on it (clutch had a 750mile break in period, and your supposed to be nice on engines that haven’t run in God knows how long). I got a used N370 ECU and put it in, then the car ran even smother, and eventually I got another JDM air pump and my alternator belts stopped snapping. I have 9.5psi peak boost with ~7psi @ redline. I did two more oil changes and a final one after I put on 800 miles since the swap, where I changed to 20W-50 Royal Purple, and new stock spark plugs (and of course new oil filter haha).
I would like to THANK everyone who has helped me on this forum with my questions, and made this swap possible and a success =) . And if anyone has question about this swap feel free to ask me, and I’ll be happy to help as much as I can!
There’s a picture before after the swap without an air pump: (and more pictures can be seen at www.myspace.com/13brotary)
02-16-07, 07:53 PM
#5
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i did the same swap. mines a little differnt however my n374 was dead as well. it killed my motor and i rebulit it w/3mm apex seals, no emish, 720 secondarys, koyo rad, rb fcd, safc II, 3"turbo back exhaust, duel alt pully, tein ra's, and a stage 2 cluch. i haven't started on the breaks yet and i still need wheels. mine's taken about a year and way to much money. this was a great write up. thanks for doing it.
02-17-07, 02:24 AM
#7
rottary89
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Originally Posted by My5ABaby
1 thing real quick... they're "brakes", not "breaks". 
Other than that, nice detailed write up (or whatever you wanna call it).
Other than that, nice detailed write up (or whatever you wanna call it).
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02-17-07, 12:25 PM
#9
rottary89
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Originally Posted by lchaidez
NICE congrats. Im in the middle of rebuilding or building either a new na engine, or turbo engine and im still lookin around for more folks from na > turbo. dammit why you gotta live so far!
lol good job.
lol good job.
