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-   -   S5 NA to turbo conversion/buildup, $15k (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s5-na-turbo-conversion-buildup-%2415k-631899/)

arghx 08-10-07 09:44 AM

that 8 looks sweet. I'm guessing that suspect it's too much bullshit to make a reliable renesis turbo? Just easier to use an older rotary then?

sc0rp7 08-10-07 11:18 AM

First time I saw this thread and I thought I would add to the praise that your car is very very freakin sweet... Clean as could be... Very nice work sir...

- Chris

RotaryResurrection 08-10-07 07:13 PM


Originally Posted by arghx (Post 7222629)
that 8 looks sweet. I'm guessing that suspect it's too much bullshit to make a reliable renesis turbo? Just easier to use an older rotary then?

It's not the engine itself, but the PCM controls that are a bitch. It is nothing like the stock computers in rx7s...it's like a nazi control system! To give you an idea, there are like 4 different types of codes that it throws if the main cat/2nd o2 sensor doesnt respond to it's liking...and if you run a midpipe you can't fool with 2nd sensor with a resistor circuit or with a sparkplug nonfouler on the sensor like you can on every other OBD2 vehicle in the world.

There are few options for engine management, none are all that awesome, and all are quite expensive. To give you an idea, there are 2 complete turbo setups that I am aware of...the small greddy kit that costs around 4k and is of questionable quality and is so tiny that power is limited to 290-300rwhp, and the larger mazsport kits with their own engine management that run...get ready...10 grand, and can get you 350-375rwhp.

Looks like I am committed for now; I made a deal last night to buy a complete 6 port/6 speed pullout from a partscar, along with most everything needed (at least, I hope) for the manual swap into my car.


Kevin, about the OMP mod...
About how large is that tank and how long does it last?
I know you suspect it is leaking into the oilpan (a bit) but a general idea would suffice.
It is about 1 quart. I have never let it get below 1/3 full, and I refill it about every 4-500 miles. Of course, I dont drive the car a lot, so when I do take it out I usually "play" some, so those are harder city miles and not really any highway. :)


Do you have the water path on your lower intake welded off? If so, why?
Uhm...no? Why would you say that? :scratch:

Valkyrie 08-10-07 09:49 PM

How do you wire the e-fan to run at a higher speed when the A/C is on? (and does it only run when the car is actually running, not whenever the ignition is on?)

Idling in 99 degree weather does not work so well for my R134A-charged A/C...

...plus, the clutch fan is just so big.

RotaryResurrection 08-10-07 10:09 PM

you have to use 2 relays, I use the 4 prong PILOT headlight/foglight relays from autozone, but you could use stock or those 5 prong style ones as well.

The stock s5 FC thermoswitch sends a ground signal when it switches on. You run that wire to the low amp side of the first relay. The other low amp terminal goes to the ignition switched output, which I get from the green plug by the leading coil. Then you pull fused battery positive from the enginebay fusebox (I used the blank spot, inserted a new fuse and terminal underneath) and it goes to a terminal on the high amp side of the first relay (and the second relay as well). Then the last terminal on the first relay feeds the low speed wire to the fan, and the fan gets grounded to the frame.

Now, with the ignition on, when the temp switch turns on at 207, the fan kicks on low speed, and when the temp switch kicks off at 195, the fan turns off.

The second relay handles the a/c function. Find the stock a/c relay in the front bumper and find which wire turns on when the a/c compressor kicks on. Splice into it and run it to the low amp side of relay 2. This is a positive wire, so the other low amp side of relay 2 needs to be grounded to the frame. Remember the fused battery positive wire from relay 1 also runs to relay 2 on the high amp side, and the remaining terminal feeds the fan's high speed wire.

Now when the ignition switch and a/c are activated, the fan kicks to high speed as long as the a/c runs, so it constantly pulls 2500cfm through the a/c core. I was first worried about wiring it this way, as this technically overrides the low speed function of relay 1 and the fan motor is not designed to have both wires/speeds fed at the same time. But after I thought about it further, with the fan on high speed, the thermoswitch is unlikely to ever actually be triggered anyway, so that shouldn't cause any conflicts.

NZConvertible 08-11-07 11:07 PM


Originally Posted by RotaryResurrection (Post 7224776)
Now, with the ignition on, when the temp switch turns on at 207, the fan kicks on low speed...

You don't think that's a little high?

RotaryResurrection 08-11-07 11:22 PM

That's lower than what mazda uses for most of their other cars. It's the stock turn-on temp for most vehicles on the road.

NZConvertible 08-11-07 11:58 PM

I just don't see the point or advantage in letting the engine temp get so much higher than the normal running temp (180-195degF). I just wondered why you did it.

RotaryResurrection 08-12-07 12:07 AM

Show me a sub $50, reliable/accurate temp switch that turns on at 195, that will thread directly into the FC waterpump housing, and I will gladly use it. :)

I used it for simplicity, availability, and ease of installation. This is the stock FC temp switch, after all.

FWIW, this is the switch that FD guys use as an upgrade to their stock temp switch, which turns on at...get ready...226*F.

Also; thermostats don't even open until 180...if you wanted a temp switch that low, there'd be no use in even using one, simply wire it straight to the ignition so it runs all the time. ...Which, btw, I have done before without issue on 89+ models, provided the charging system is in great health. The 88 and older models seem to struggle with even maintaining proper charge on a bone stock car, so I don't recommend any additional amp draw on those.

NZConvertible 08-12-07 06:05 AM


Originally Posted by RotaryResurrection (Post 7227143)
Show me a sub $50, reliable/accurate temp switch that turns on at 195, that will thread directly into the FC waterpump housing, and I will gladly use it. :)

No problem. Use the ECU thermosensor voltage as the input to this this adjustable voltage switch, which will then activate your fan relay at any temp you want with any hysterisis you want for US$36 shipped. :)

http://autospeed.drive.com.au/cms/A_2476/article.html


I used it for simplicity, availability, and ease of installation. This is the stock FC temp switch, after all.
I can certainly appreciate that.


FWIW, this is the switch that FD guys use as an upgrade to their stock temp switch, which turns on at...get ready...226*F.
The fans actually turn on at 221degF and go up a speed at 226degF, but that still seems frickin' nuts to me. I just can't see any rational engineering justification for that, other than maybe lowering emissions (just a guess). If I had an FD I'd seriously consider using two of those voltage switches above to set those temps lower.


Also; thermostats don't even open until 180...if you wanted a temp switch that low, there'd be no use in even using one, simply wire it straight to the ignition so it runs all the time.
Why would I want a switch that low? I'd want the switch to operate just above the engine's normal temp range. Remember I'm the one normally telling you not to run e-fans constantly like your website suggests... ;)

r0k0 08-12-07 10:24 AM

where did you get your lip from...?

87 t-66 08-12-07 10:40 AM


Originally Posted by r0k0 (Post 7227692)
where did you get your lip from...?

its a stock s5 t2 lip. i think japan2la and fc3s91 sell them new.

r0k0 08-12-07 10:43 AM

oh really.. wow..

oh well i still bought the Type Ms lip from Corksport.. :P

but that lip is so awesome.. i would of love that one even more..!


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