Rediculous e36 rotary valve engine project

[pizzaman09]

Dyno day is tomorrow! It's all loaded on the trailer and it is running even better than the last update video. We fixed up all of the intake leaks and put fresh spark plugs in it.

[pizzaman09]

Dyno tunning was quite the informative experience. Good progress was made in making the car run better but it is apparent some fiddling with the tune is needed yet. We kept running into a sudden change in performance north of 4200 rpm at WOT and couldn't exceed 6000 rpm under the high load of the dyno. We think the issue is the ECU is pulling timing due to a change of state, possibly VANOS turning off.

At peak we made 106 RWHP and 127 ft-lbs of torque. The torque curve was basically flat from 1500 to 5000 rpm.

[KinkedChrome]

This is a wild project. Really great work. However, i think the most impressive thing to me is how flat the torque curve its throughout the entire rpm range. I wish area under the power curve was a more important figure to people than peak HP.

[pizzaman09]

Still working out the kinks on this project. I determined today that the clutch in the fan is not working correctly which could explain why the engine over heats after 10 minutes regardless of how much coolant flow is going through the radiator.

In any case, here is a recent video of it running and idling as well as a show an tell of the build.

[spyderg0d]

If you have the accessory fan installed, it should kick on when the engine reaches temps, force air through the rad, and allow the coolant to cool the engine given the water pump is flowing it. Even at idle.
I think your issue is probably related to a variable in your assembled system.
I dont know if you used a stock modified head or not for coolant passages. Oil passages and how you deal with that. Combustion chamber dimension vs. Compression rates vs, airflow rates at various rpms. Theres also exhaust flow and the internal contact area of the combustion(ed) gases to consider for heat retention. Id imagine the contact area would probably atleast triple internally for exhaust, the volume lessened from the lack of regular intake dynamics decreasing efficiency, and the overall combustion process itself diminished and less efficient resulting in a longer or uneven burn.
Id imagine domed pistons might help a bit.

[pizzaman09]

If you have the accessory fan installed, it should kick on when the engine reaches temps, force air through the rad, and allow the coolant to cool the engine given the water pump is flowing it. Even at idle.
I think your issue is probably related to a variable in your assembled system.
I dont know if you used a stock modified head or not for coolant passages. Oil passages and how you deal with that. Combustion chamber dimension vs. Compression rates vs, airflow rates at various rpms. Theres also exhaust flow and the internal contact area of the combustion(ed) gases to consider for heat retention. Id imagine the contact area would probably atleast triple internally for exhaust, the volume lessened from the lack of regular intake dynamics decreasing efficiency, and the overall combustion process itself diminished and less efficient resulting in a longer or uneven burn.
Id imagine domed pistons might help a bit.

Thanks for the reply!
Do you happen to know what controls the electric auxiliary fan to kick in? I have never had it kick in on this e36, I had always assumed it was only part of the air conditioning system. I have the coolant temperature functioning properly so the ECU should be getting the signal it needs to tell the fan to turn on.

In terms of flow rates of coolant through the system, it is quite suspect. The entire engine head has been replaced with the custom rotary valve design. There are coolant passages very near the combustion chamber likely picking up significant amounts of heat. Additionally there are coolant passages right near the exhaust manifold flange that are keeping a set of rotary shaft seals cool as they are running right on the hot exhaust side of the rotary valve. The flow area I know is signficantly smaller than the OEM setup and I have considered running a bypass that keep coolant flowing through part of the system. However it really seems to me that the system just isn't rejecting heat so I think the next thing to try is to get the viscous coupling on the fan working again.

[pbonsalb]

Aux fan is controlled by the switch on the cold (passenger) side of the radiator. Those are essentially the trigger wires that ground the high and low speed relays for the fan and allow power to the fan. The fan will also run with the ac compressor. 20 year old fans are at or near the end of their life. Apply power directly to the harness under the fan to see if it works. If

[pizzaman09]

Aux fan is controlled by the switch on the cold (passenger) side of the radiator. Those are essentially the trigger wires that ground the high and low speed relays for the fan and allow power to the fan. The fan will also run with the ac compressor. 20 year old fans are at or near the end of their life. Apply power directly to the harness under the fan to see if it works. If

Cool, thanks! That particular plug like to come off on my 328 as it is missing the clip, I will check that out soon to see if the aux fan works. I have also ordered a new viscous fan clutch.

[Sleepyhead97]

You guys are amazing!

[spyderg0d]

The mechanical fan more or less is a constant flow through the bay,. Its more or less for heat soak of componants and anything in the bay than it is for the engine until the weather is in extreme heat.
I certainyl would have checked coolant flow rate and routes through the head firstly in the mock up process.