Building an engine dyno.

[Cam]

Thank you for clarifying that Trevor. I understand what was said much better now .

I still think it would be fun to take a class that focused on the engineering aspects of combustion engines and other automotive applied sciences. Knowledge is power, after all

[Dessertrunner]

Trevor you still getting me wrong. The cruise is not connected to the engine the only thing it has to do with the engine is it reads the speed of the motor in rpm. The cable is used to control the Varic unit not the throttle on the engine as you keep mentioning.

The problem with doing as you suggest is that as soon as the motor RPM speeds up the ECU is reading a new part of the table. Its a whole lot more difficult then dealing with constant revs.
Tony

[Dessertrunner]

Did some quick maths based on Phil's info of 4 pulses per rev on the tyre. I maybe able to hook the rev counter output from the ECU to drive the cruise direct. If my rough calcs are right the crusie will work above 1,200 rpm.
Need to do some checks to see if what I think is correct.

By the way I have completed the construction of the dyno with the exception of,
Mounting starter
Fit up load cell.
Fuel pump to the motor.
Battery
ECU wiring

so I am getting there
Tony

[Dessertrunner]

Well team spun the unit over on the starter to day so the job is geting closer to completation.

A question for you guys is "What does the fuel pump modlator do?

Adam if you are out there how do you handle the ECU issues when you are dynoing the different engines?

Tony

[Trevor]

Originally Posted by Dessertrunner

Well team spun the unit over on the starter to day so the job is geting closer to completation.

A question for you guys is "What does the fuel pump modlator do?

Adam if you are out there how do you handle the ECU issues when you are dynoing the different engines?

Tony

Kia oira Tony,

The fuel pump modulator controls the output of the fuel pump in two stages, full output or a reduced output. A resistor in series with the pump drops the supply voltage and therefore reduces output. When full output is required the modulator bypasses the resistor, so that full voltage results in the pump delivering full output.

You will not be involved with lengthy slow running, as so often occurs with a car on the road. As as result you should be able to run the pump continuously at full output, with the surplus fuel returning to the tank. Therefore the modulator and resistor need not be fitted.

Cheers, Trevor.

[Dessertrunner]

Trevor,
Thanks for that it all makes sense I understand what you are saying.

Its a bit of a challange to cut the ecu harness out of the half cut have had to solider a cuple of wires back after I cut the wrong ones.

I think it going to be a case of cross my finger and hope for the best.

Tony

[Boxersix]

ah gutting the harness for the necessary wires is easy. I can walk ya through it if needed, done about a dozen of them here for myself and other EG33 swaps.


What ECU issues are you referring to? If you're talking about how do I operate say a Corvette LS1 one day, then a Nissan RB26DETT the other....I have a harness and PCM for every motor I can run. If it's an oddball engine the customer typically provides a standalone EMS and harness that I just apply the necessary power/grounds and key on sources.

[Dessertrunner]

Adam when you have set up the ECU did you bother connecting the O2 sensors?
Tony

[Boxersix]

Originally Posted by Dessertrunner

Adam when you have set up the ECU did you bother connecting the O2 sensors?
Tony

Absoltely required if using stock ECU. If you have an EMS using WBO2 input, it would be wise to use that.

[Dessertrunner]

Radiator mounted, battery box in place, load cell arrived still need to mount it.
Big project for the weekend is sort out the ECU, connect the fuel and sort out exhaust.

Will keep you all posted.
Tony

[Dessertrunner]

Have hit a problem,
In the manual on the page headed "Power Supply Routing" the Ignition Switch shows power going to "IG-2". I can't find were this goes to and I also can't figure out how the main relay is turned on.

Anyone got any ideas?
Tony

[Trevor]

Originally Posted by Dessertrunner

Have hit a problem,
In the manual on the page headed "Power Supply Routing" the Ignition Switch shows power going to "IG-2". I can't find were this goes to and I also can't figure out how the main relay is turned on.

Anyone got any ideas?
Tony

IG - 2 denotes a point where various items, only energised when the ignition switch is in the accessory position, are connected. You are not involved in these accessories so can ignore the connection.

The main relay has one side grounded and is turned on via a diode blocking a sneak circuit involving the ECU, with the diode connected to the positive supply to the fuel pump. Therefore the two relays are energised together from fuse number 16 when the ignition is turned on. Refer 6 - 3 - 15, page 44, Engine Electrical (MPFI) System.

[Dessertrunner]

Hi Trevor,
I think fuse 16 is in the small fuse box not the main, so I have re wired to the main fues box.
Currently I am using the head light relays for the starter circut and put an addiational relay unit to act as ignition switch so I don't have to switch high load throught my new ignition switch.

My reason for using these is I need tocontrol the starter etc from a PLC.

Thanks for clarifying that for me Trevor it makes sense. Hopefully I will get a Engine start tomorrow. By the end of next week I hope to read the dyno getingsome rough numbers.
Tony

[Dessertrunner]

Here is a couple of photos as to were I am at. Finding a place to mount the ECU was a bit of a pain so I mounted it on a plate that is mounted on rubbers to protect it from vibration.
Tony

[Dessertrunner]

Okay, lastest issue, got no start seems to not have spark. I need to set up the check engine code light so I can pull the error code.
Have a heavy blue wire coming from the front right side of engine that I can't find a home for any ideas?
Tony