Building an engine dyno.

Dessertrunner · #1 05-23-2010, 02:06 AM

Over the last couple of months I have come top the conclusion that we basicly have no solid number on what each mod will do to our engines as regards power. We make a number of changes and have no idea if they all worked or only some.
I have redesigned the roller throttle port size lots of times and clearly have no clear idea which is best. Having read that recent artical I have change my mind again so i want to be able to run tests to be able to give clear direction.

Okay enough reason, now to "HOW I THINK I WILL DO It",
I am talking to a guy to buy a "Eddy Retarders from a truck" this is then anchoured with a strain guage to measure the torque and a prox reading revs.
From that you get to calc HP and torque at the different revs.

Was going to use a water pump but they have issue and are a bit difficult for me to find.
Tony

Dessertrunner · #2 05-25-2010, 05:22 AM

You guy are pretty quite,

I paid for the Telma eddy Retarder today (PDF of the unit is attached). It provides the load for the engine. A shaft is connected to the front and back for support with the front attached to a pulley and chain driven to a shaft driven from the engine. Eddy current units are limited to around 4,000 rpm so thats why the cahin drive. I am using 2.5 reduction to enable the unit to read up to 10,000 rpm on the motor & 1,600nm.
The centre section of the retarder is floating and will be fitted with a 1 ft lever at the end of which is a strain guage (set of scales). At any point in time its just a simple matter to read the pound weight and you have the ft pound the engine is producing. At the same time measure revs and you can calc the HP being produced.
I am ahead of myself a bit we control the load on the engine by feeding between 0 to 24vDC to the coils (using a old electric forklift charger) on the retarder as required to keep the engine at full load.
I recently purchased a half cut and I will pull the ECU and wiring harness from it to enable me set up the test bed.
My plan is to start with a stock standard low k engine (100,000 kilometer is low to me). Attach it as if it was in a car, full exhaust, standard intake then do a couple of base line numbers.
Then with out touching the internals of the engine I want to see what can be done to get more power from the out side, extrators, different ECU (have got the Wolf going), different injectors & roller throttle. All of it one step at a time to put solid number at each stage.

Okay thats it for me for the moment will keep you posted as I go, given that it is the slow part of the year (only working 60hour now) for me I want it all built and running in the next 6 weeks or sooner.
Have a great day all.
Tony

SilverSpear · #3 05-25-2010, 06:05 AM

Good luck Tony

Nomad · #4 05-25-2010, 08:52 AM

I'll be reading that ! Very interresting to know real numbers.

TomsSVX · #5 05-25-2010, 02:13 PM

was also thinking about build/purchasing one a while back... Quickly realized it would be cheaper albeit inefficient on time to just dyno the car on a chassis dyno

Tom

Dessertrunner · #6 05-25-2010, 03:06 PM

I had the same thought Tom and agree that is cheaper.
Clearly thought you never get the research done that is need to develop the SVX engine. Take for example cams. On a engine dyno you don't run timing belt covers, and when you want to change the cam its a simple matter. If the engine is in the car you have to pull it, put it back everytime.
I don't know of any serious race engine that has been developed that hasn't spent time on a engine dyno.

Besides a guy needs a hobby to keep him off the streets.
Have a great day.
Tony