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spla300

bought an rx7, any tips welcome

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Does anyone use lower temp thermostat?
The stock one is 82deg which seems a little high considering engines get pretty hot. There is a 75 and 68deg ones, would 68 be too low? Anyone have some experience with different thermostats?

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@Chief Wiggum& @Bradyy were looking into the different thermostats a while ago I think, worth asking them or doing a quick search on RX7Club.com or FDUK as someone over there might've done it. One thing to beware of with RX7Club: a lot of them are based in the US in much hotter climates than Ireland so their experience & recommendations may not suit these climates.

Also note that the optimal oil temperature is around 80-90 degrees anyway so once the stock cooling system isn't going much above 105-110 Celcius range the engine should still be in a good place.

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Time frame is as soon as I get money together.
All i need to get is front mount intercooler now and thats pretty much the engine bay complete she will be driveable. then it's all down to sanding and spraying.

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Oh yeah cant wait to see what the Clutch feels like without the springs.
Also I've got a 12psi spring in the external wastegate I'm guessing that's too much boost for the stock ecu. I wonder if I put an 8psi spring in would the ecu handle the fueling ok?

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Not sure what turbo you are using but il guess it flows a lot more than the stock turbos. At 12 psi where the stock turbo would have enough fuel, a single turbo setup with a less restrictive exhaust manifold will max out the injectors causing lean conditions. Idealy you dont want injector duty above 90% max which you cant monitor on stock ecu. The ecu will also be trying to control boost to under 10 psi so there might be issues there. Safest bet would be to use the 8 psi spring and run boost at spring pressure and hardwired the fuel pump if not already done. With a ported engine and less restrictive exhaust and a turbo flowing higher cfm than stock at same boost the best thing is to run it off boost til you get an aftermarket ecu and mapped correctly. I assume you are on stock injectors with the ecu.

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I have a t04z Turbo I just wanna have it running the way she is just to brake in engine for now. I have an ecumaster black edition which I'll wire in at a later date and I'll have to buy injectors.
I've yet to buy a walbro pump for it and I'll wire that in directly. As for spring I could even cut a coil off it to reduce it further to maybe 5psi if 8psi might still be too much.
I'll also be fitting a wideband into her at a later date.

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On 1/12/2017 at 5:22 PM, spla300 said:

As for spring I could even cut a coil off it to reduce it further to maybe 5psi if 8psi might still be too much.
I'll also be fitting a wideband into her at a later date.

If you shorten the spring for your wastegate, it may not have any preload to keep the flap shut, so it won't spool. Also, when cutting coils of a spring, it actually makes it stiffer. If you remove all the coils from a spring, it becomes a stick.

Regarding the wideband, if you have it already, you can wire it in, and depending on the model, it may have an "emulated narrowband" output that you can wire in place of your oem narrowband signal, so you don't have to add a second O2 sensor boss, and this way, you can monitor your AFR using a gauge or using a laptop. Even for breaking the engine in, better be safe than sorry, it takes only seconds for detonations to break an engine, while it takes hours/days to rebuild!

Nico

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Well done fella, that's some progress! ;) Great sound too!! B):D

On 01/12/2017 at 4:17 PM, spla300 said:

Also I've got a 12psi spring in the external wastegate I'm guessing that's too much boost for the stock ecu. I wonder if I put an 8psi spring in would the ecu handle the fueling ok?

What Nico & Laned3 said. ^^

Were I in your shoes, I wouldn't trust the stock ECU to fuel that turbo at all correctly: the flow characteristics in the T04Z on whatever porting you've done to yours are likely completely different from the the flow characteristics of the stock twins so your fuelling & ignition timing will be all over the place (in comparison) & you've more risk of doing damage to the engine than anything else.

For the break-in period until you've some sort of map on it I'd suggest running no boost; so if you've a boost controller turning the gain all the way down, boost all the way down, & setting a warning for anything above vacuum/0.0bar.

Even for the break-in period, if your aftermarket ECU has a 13B basemap I'd suggest installing it as a priority. Failing no basemap being available from the manufacturer, I'd look for others that run a rotary with a similar single turbo setup & (if you trust the source) ask them nicely for their map so that it'll at least start/run & allow you to rev it up to the point where you can break the engine in & then map it properly.

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Awesome thanks for thr help.
I'll stay out of boost for now.
Would anyone have a broken stock ecu for sale Maybe? I need the connector from it so I can connect my ecumaster.
Also would anyone have an ignition map please?
Once I've that the ecu has an autotune feature for the injector map, I'll just set it to keep it at 10-11 afr and it will adjust the fuelling itself.

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On 06/12/2017 at 9:10 PM, spla300 said:

Once I've that the ecu has an autotune feature for the injector map, I'll just set it to keep it at 10-11 afr and it will adjust the fuelling itself.

As a heads-up 10-11 AFR is super-rich unless you're on full load. I can imagine you're trying to be conservative with the fuelling so it might be worth aiming for 14.7 as the norm (stock) for idle & low-load cruising AFRs. When tuning you can usually go leaner than 14.7/15 while on light-load situations like constant-speed cruising & sometimes idling, & 13s under medium-load conditions that either don't involve boost or have very light boost.

If you wanted to be "safe" then everything outside of the idle cells aim for 13s at most but if you're doing many miles on this remember you're likely overfuelling & so carbon buildup on the likes of plugs etc may occur (over time but possibly not for the few miles you'll be doing to get it run-in/to a tuner's place).

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Hi guys it's been a while since last update not getting time to get to her.
She did start to act up however. She fired up no problem until I bled the clutch and got in to drive her slowly in a circle in the car park for first time not even accelerating.
Then she cut out and starting her is a struggle she keeps flooding. Injectors checked they are not leaking and are injecting as they should. Rear rotor at firewall does get flooded more.
You can hear in the vid she is trying to pick up but something not letting it. Is it a misfire? I know what piston engine misfire sounds like no idea of rotary.
Plugs and leads are brand new and compression is 6bar on all rotors and 8bar with a little oil. Check out vid let me know what you guys think.



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Yeah that sounds like a misfire alright.

 

So just to be clear: is the car is running on...

- A stock ECU for the moment (or is the aftermarket one wired in yet?)

- Stock injectors (have these been flow-tested?)

- Stock fuel pump & fuel pressure regulator

- Stock coils (used in a car that was running perfectly? If no, have you another car to test them in or have you a coil tester?)

- Mazda/aftermarket leads (connected from the correct coils to the correct plugs?)

- 7s (leading/lower housing position) & 9s (trailing/top position) spark plugs? When that video was taken, were the sparks confirmed as still being in perfect nick, not soaked in fuel or coked in carbon? (All it can take is one bad flooding & being left to kill off a set of plugs sometimes)

 

Also, have you...

- Changed the fuel filter?

- Drained the tank of old fuel if any of it was sitting in the tank for 1+ years?

- Added fresh fuel to the tank?

- Connected up all the necessary vacuum lines to the inlet manifolds (lower & upper) to avoid any vacuum leaks? (& blanked off any that aren't being used)

 

Finally, does this change at all when...

- The engine is stone cold?

- The engine warms up?

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Still on stock ECU.
Stock injectors.
Pulled fuel rail out and cranked it both injectors have nice even spray. No leaks.
Stock fuel pump for now.
Stock FPR.
Coils are stock I don't have another car to test them in.
I have a bulb thing that goes over spark plug and the lead goes over the bulb and bulb flashes when there is spark if that's what you mean by coil tester?
Leads are connected the right way.
Brand new leads.
Brand new NGK plugs BUR9EQP all 4 the same.
Fuel tank has been drained and cleaned fresh fuel put in and new fuel lines used no fuel filter installed for now.
Checked the system for boost leaks all is good.
Engine runs the same hot or cold.
I did notice the rear rotor gets flooded very easily and a load of fuel comes out the spark plug holes.
Maybe it's the coil pack not functioning right and not strong enough to ignite the fuel.
Any ideas how to check the coil packs?

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Did you check both sets, in other words all 4 injectors yeah?

Have you checked all the wiring around the engine bay, in particular around the injectors?

Yeah a coil tester like that would do for low/no-load situations like idling. I know one of the guys up North created his own coil tester to check for spark when coils are under load, that's the only alternative that I know of - having said that you could ask around for a set of known good coils to eliminate that possibility?

If one rotor is constantly flooding & diagnosing the root cause is becoming difficult to logically determine or you don't have the necessary equipment to test everything that could be wrong, I'd focus my efforts on swapping out components with ones that are running fine in someone else's car until you find the issue.

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