Chassis dyno for engine break in, Is it a good idea? Options

[nine14cats]

If all goes well The Beast™ will be back in my garage by October 28th. Randal and I can then finish all of the little things and she will be ready to go.

As the motor is newly rebuilt with ZERO hours on it, I was thinking about the best way to break in the motor. Our engine builder has given us a sequence that he uses. Our first thought was to take it to the track and use the first 2 sessions to break it in. However, there is a risk that if we run into issues we will be far from home and have to deal with the inconvenience of coming home in the middle of the day.

I have a chassis dyno that is close to me and gets $135 / hour to set up your car. The unit is programmable for the load on the car. I'm thinking this may be a much easier way to break the motor in. The dyno is located in a business park, so the owner says that 20 minute pulls are no problem. Two pulls and we should be good to go. I could then bring the car home, change the oil, and be ready for some fun!

Anyone ever done this? Engine dyno's break in motors all time, so I don't see a downside.

Any comments / experiences would be appreciated.

Thanks,

Bill P.

[Twystd1]

A wide band o2 sensor (Lamda) and EGT are your friends in this circumstance.

A fuel metering/measurement system will allow to you look at your BSFCs and help target your tune.

And yes you need a bung for the o2. An extractor exhaust like a Type 1 or Type 4 is too long put a o2 at the end of the pipe and expect critically accurate data in real time. (I.E. smog machine setup)

And no you don't necessarily need a bung for an EGT. You can simply drill a hole in your exhaust and clamp it in place with a stainless hose clamp.
(4 inches or so from your exhaust port is best, if possible)

Next question is... How the hell do I fill four 3/16s holes I just drilled in my totally bitchin and expensive ceramic coated headers???????????

Just thread it for a 3/16s allen "set screw" and safety wire it in by drilling the set screw and tossing a wire through it and wrap it around your pipe.

That allows you to install an EGT sensor whenever you want to.

If ChrisNprider will post up the set of headers I sold him. You can see that exact setup. Works bitchin and is fast to plug up. Or remove screws to use on a dyno.

This assumes the dyno you are using has solid data logging and has an EGT probe you can use.

And head temp. And oil temp...etc...etc...

Does this take time and money? YUP

Is this one of the best ways to set up an engine? YUP

Realtime data logging is the only way I know of to really know what the engine is doing.

Note: Your engine will take as much as timing and fuel as IT wants.
If you listen to the engine and watch the data, interesting things happen.
YOUR ENGINE WILL TELL YOU WHAT IT WANTS.
Then it's your job to deliver the goods to your engine.

This is a most interesting symbiosis.
IMHO: Thats in part why Jake, or Stewart Van Dyne or Darrin Morgan and many others are so good at their craft.
They understand this relationship and exploit it to the fullest.

No two engines are the same. Each one wants a different tune to maximize potential. And an experienced technician can really help you on this.

In truth. Guys like Jake and others have more pertinent data specific to your question than I.

I am a pretty solid back yard mechanic at best. Not a pro. (Far from it)

I suggest you wait for Jake and others to get back from their weekend and get some more data from the guys that do this for a living.

More useless data: You and I can't hear pinging on a dyno very well. Unless it's pretty loud.
Problem is. By the time your hear it. It has been going on long before it became audible.
Thats why the instrumentation of the engine is so important.
It helps keep you in the safe zone.

And gives you an idea on how far you can enter the danger zone.

I hope I have confused you even more than my previous post..... (IMG:style_emoticons/default/chair.gif)

Cheers,
Clayton