Coming into a free 88 RX7 TII time capsule full of mystery mods.
04-21-23, 03:27 PM
#1
80's cars
Thread Starter
Coming into a free 88 RX7 TII time capsule full of mystery mods.
Hello everyone. It's a long story how I got the car for free, but I didn't have the most accurate info one what was done to the car. This car sat for 9-10 years. After hearing and investigating what was done, here is what I gathered. (I did do a compression test and it seemed okay too btw)
That being said, I have a couple questions, maybe for the people with the old school knowledge. It appears that I have rtek 1.7 to me. According to rtek's site in order to use 720cc injectors it requires version 1.7. On the front the the ECU it says 720cc, and although the stick looks like it's just 1.0 it almost looks like someone wrote a 7 over the 0 and it faded away.
Thanks! Also despite my long time membership this is indeed my first RX7, so I'm trying to search and learn as much as I can, but there is so much outdated information
- Hybrid Turbo (trim unknown)
- Streetport 89 motor (keg?)
- FMIC (which was so bad that I replaced it with another brand)
- All emissions removed, 3"+ exhaust straight from the the Turbo
- AC / PS deleted.
- Koyo Rad
- AFR gauge (not working but I'm getting on that)
- Short throw / Clutch I believe
- Mystery RC aftermarket injectors (and I assume a fuel pump based on this)
That being said, I have a couple questions, maybe for the people with the old school knowledge. It appears that I have rtek 1.7 to me. According to rtek's site in order to use 720cc injectors it requires version 1.7. On the front the the ECU it says 720cc, and although the stick looks like it's just 1.0 it almost looks like someone wrote a 7 over the 0 and it faded away.
- Based on the pictures would you also assume that's 1.7?
- I know to make real power / control I would need to go with a real standalone, but I'm on a budget for awhile. What would a few cheap options at this mod level to either make the car more reliable, fine tune it, or make more power? I was told a manual boost is unnecessary since the turbo is spring controlled, is that true?
- Basically beyond the obvious maintenance, where do I go from here on a tight budget? Not looking for anything crazy but some simple additions could be nice.
Thanks! Also despite my long time membership this is indeed my first RX7, so I'm trying to search and learn as much as I can, but there is so much outdated information
04-22-23, 09:46 AM
#2
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on a tight budget your best bet is to service the car, and then verify the tune. depending on where the tune ends up, you maybe have some room to do stuff.
what does that mean? as part of the service work you should change both fuel filters, 952-0043 is the in tank part. i like to verify that the voltage at the pump is within about 0.5v of the battery, if its not you should be looking for voltage drops.
spark plugs you might want something colder than the 7/9's, any JDM tuner would be running 10's for a setup like this https://www.rhdjapan.com/ngk-r7420-r...-range-10.html HKS, and Denso all have colder plugs
wires should be checked, Mazda's spec of 16k Ohms per meter is the maximum, new wires are about 8k. we want to avoid any "inductive cross fire" so you can either cross all the wires at 90 degrees, or route the trailing wires away from the leading wires. i like to check and set the timing right on the mark, if the timing is off, you might want to mark where it is, maybe its that way for a reason.
new thermostat is a good idea. also you probably want to make sure the cap(s) are good.
to verify the tune i would add/borrow a wideband 02 setup and make sure the AFR's are good. i'm not sure what that setup is supposed to do, but we're looking for something in the 10.5-11.5 afr range at like 12-13psi.
that ecu is kind of a wild card, its possible it got a 720cc tune. you might do some searching on here, its possible the car has a build thread or something
depending on the turbo it has, and how much boost its running you should be in the 260-280rwhp area, which is a lot of fun, you're going to want to work on the suspension if it hasn't been done yet!
what does that mean? as part of the service work you should change both fuel filters, 952-0043 is the in tank part. i like to verify that the voltage at the pump is within about 0.5v of the battery, if its not you should be looking for voltage drops.
spark plugs you might want something colder than the 7/9's, any JDM tuner would be running 10's for a setup like this https://www.rhdjapan.com/ngk-r7420-r...-range-10.html HKS, and Denso all have colder plugs
wires should be checked, Mazda's spec of 16k Ohms per meter is the maximum, new wires are about 8k. we want to avoid any "inductive cross fire" so you can either cross all the wires at 90 degrees, or route the trailing wires away from the leading wires. i like to check and set the timing right on the mark, if the timing is off, you might want to mark where it is, maybe its that way for a reason.
new thermostat is a good idea. also you probably want to make sure the cap(s) are good.
to verify the tune i would add/borrow a wideband 02 setup and make sure the AFR's are good. i'm not sure what that setup is supposed to do, but we're looking for something in the 10.5-11.5 afr range at like 12-13psi.
that ecu is kind of a wild card, its possible it got a 720cc tune. you might do some searching on here, its possible the car has a build thread or something
depending on the turbo it has, and how much boost its running you should be in the 260-280rwhp area, which is a lot of fun, you're going to want to work on the suspension if it hasn't been done yet!
Last edited by j9fd3s; 04-22-23 at 09:48 AM.
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04-22-23, 11:40 AM
#3
80's cars
Thread Starter
Thanks for the reply. Yeah the wideband is something I plan on getting next, preferably something that would work well with a standalone in the distant future.
04-22-23, 01:44 PM
#4
Please search for my posts I’ve made on similar threads within a few months regarding older style ecu’s and piggybacks (rtek, apexi safc).
In 2023, people on here seem to think the rtek’s don’t work and prefer newer ecu’s. Back then, a lot of people (including myself) used rtek ecu’s and paired them with a safc to dial in the fuel, and they worked great. In recent years, stand-alone technology has really taken off so a lot of guys are running to the newer ecu’s. But the rtek & safc combination does work. Read my posts on the negatives of using the safc to pull or add too much fuel.
There is a thread made by the creator of rtek ecu’s which states what power levels are possible with each 1.0, 1.7, 1.8, 2.xx.
I don’t think the rtek 1.7 with 550cc primary/ 720cc secondaries are going to keep up with the potential the hybrid turbo has at higher boost levels.
get your injectors tested, cleaned, retested to verify flow rates and make sure they’re flowing properly. if the secondaries are ~720cc, I’d fire it up, and after everything’s squared away, go into low boost and see what the afr’s are. If it’s stupid rich, you probably have the rtek 1.0 as the ecu thinks it has 550cc secondaries.
If the block has been sitting, put some marvel mystery oil through the spark plug holes and rotate by hand over a couple of days to loosen everything up and build compression. There is a chance the oil control o-rings have dry rotted and it will burn oil, but we shall see after you get it running.
good luck.
In 2023, people on here seem to think the rtek’s don’t work and prefer newer ecu’s. Back then, a lot of people (including myself) used rtek ecu’s and paired them with a safc to dial in the fuel, and they worked great. In recent years, stand-alone technology has really taken off so a lot of guys are running to the newer ecu’s. But the rtek & safc combination does work. Read my posts on the negatives of using the safc to pull or add too much fuel.
There is a thread made by the creator of rtek ecu’s which states what power levels are possible with each 1.0, 1.7, 1.8, 2.xx.
I don’t think the rtek 1.7 with 550cc primary/ 720cc secondaries are going to keep up with the potential the hybrid turbo has at higher boost levels.
get your injectors tested, cleaned, retested to verify flow rates and make sure they’re flowing properly. if the secondaries are ~720cc, I’d fire it up, and after everything’s squared away, go into low boost and see what the afr’s are. If it’s stupid rich, you probably have the rtek 1.0 as the ecu thinks it has 550cc secondaries.
If the block has been sitting, put some marvel mystery oil through the spark plug holes and rotate by hand over a couple of days to loosen everything up and build compression. There is a chance the oil control o-rings have dry rotted and it will burn oil, but we shall see after you get it running.
good luck.
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04-22-23, 08:24 PM
#5
80's cars
Thread Starter
Please search for my posts I’ve made on similar threads within a few months regarding older style ecu’s and piggybacks (rtek, apexi safc).
In 2023, people on here seem to think the rtek’s don’t work and prefer newer ecu’s. Back then, a lot of people (including myself) used rtek ecu’s and paired them with a safc to dial in the fuel, and they worked great. In recent years, stand-alone technology has really taken off so a lot of guys are running to the newer ecu’s. But the rtek & safc combination does work. Read my posts on the negatives of using the safc to pull or add too much fuel.
There is a thread made by the creator of rtek ecu’s which states what power levels are possible with each 1.0, 1.7, 1.8, 2.xx.
I don’t think the rtek 1.7 with 550cc primary/ 720cc secondaries are going to keep up with the potential the hybrid turbo has at higher boost levels.
get your injectors tested, cleaned, retested to verify flow rates and make sure they’re flowing properly. if the secondaries are ~720cc, I’d fire it up, and after everything’s squared away, go into low boost and see what the afr’s are. If it’s stupid rich, you probably have the rtek 1.0 as the ecu thinks it has 550cc secondaries.
If the block has been sitting, put some marvel mystery oil through the spark plug holes and rotate by hand over a couple of days to loosen everything up and build compression. There is a chance the oil control o-rings have dry rotted and it will burn oil, but we shall see after you get it running.
good luck.
In 2023, people on here seem to think the rtek’s don’t work and prefer newer ecu’s. Back then, a lot of people (including myself) used rtek ecu’s and paired them with a safc to dial in the fuel, and they worked great. In recent years, stand-alone technology has really taken off so a lot of guys are running to the newer ecu’s. But the rtek & safc combination does work. Read my posts on the negatives of using the safc to pull or add too much fuel.
There is a thread made by the creator of rtek ecu’s which states what power levels are possible with each 1.0, 1.7, 1.8, 2.xx.
I don’t think the rtek 1.7 with 550cc primary/ 720cc secondaries are going to keep up with the potential the hybrid turbo has at higher boost levels.
get your injectors tested, cleaned, retested to verify flow rates and make sure they’re flowing properly. if the secondaries are ~720cc, I’d fire it up, and after everything’s squared away, go into low boost and see what the afr’s are. If it’s stupid rich, you probably have the rtek 1.0 as the ecu thinks it has 550cc secondaries.
If the block has been sitting, put some marvel mystery oil through the spark plug holes and rotate by hand over a couple of days to loosen everything up and build compression. There is a chance the oil control o-rings have dry rotted and it will burn oil, but we shall see after you get it running.
good luck.
04-23-23, 10:40 AM
#6
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i agree with the good DR, plenty of people did really well with stock based ECU's, especially if you're on a budget. you do need to verify everything the ECU is hooked to though.
worst thing about the stock ECU is actually getting it to idle, vacuum leaks are a good first place to look.
worst thing about the stock ECU is actually getting it to idle, vacuum leaks are a good first place to look.
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