Thread: Engine dyno question

Tweet

Another question guys,

I am about to finish an engine build with my dad, and we're wanting to put it on an engine dyno and tune it for max power. We are going to test fire it in the shop, do the 20 minutes at about 2000 r.p.m. to break in the cam, and run it long enough to make sure everything is working all right. My question , is it going to be hard on the engine to do dyno pulls with the engine still fresh? This will be my first time putting anything on a dyno and I want all to go well.


I appreciate any feedback fellas.

Adam

Any dyno pull is tough on an engine.... But so is making countless passes on the road trying to get it to work correctly!!! If you are with a good dyno man, the whole process shouldn't be more then 2 or 3 pulls. The tune up process IMO is sooooo much easier on a dyno, be it chassis or engine, because all the specifics of the pull are right there on the computer print out...
\
As far as being tough on a new engine, if it's built correctly and clearanced properly, no big deal....

.....I've only had two engines built but I've had both of them run on a flywheel dyno before putting them in the cars. I swear by them, don't think I would ever put a fresh engine in a car without dyno tunning it. Unless I had access to a rear wheel dyno. The only rear wheel dyno in my area only does the dyno pulls, no tune up involved such as jets & timing changes.... The first engine I had built put out something like 30 - 40 more HP on the last pull versus the first pull. And all in a couple of hours, it would take me 10 years to get that done on the street, if in fact I ever even did it!!! Plus, if somethings wrong with the motor your going to know it RIGHT away. I was told by both engine builders who built my motors that it didn't hurt anything to dyno an engine. Unless it's built wrong & if it is I want to know now not 200 miles down the road when the motor is in the car.... Bill

The guy running the dyno is the key. your looking for correct timing advance and carb jets. your going to screw with this stuff afterward anyway, so be sure to write it down so you can get back home when your lost.

Bill brought up a good point. If you DON'T dyno the engine, how are you going to know what the changes do to the engine???? A dyno printout is way more accurate then seat of the pants feel, and not near as susceptible to all the variables of trying to tune it at the drag strip by the old change stuff, make a pass, change stuff, make a pass method......

mod note: moved to engine talk