Easy methods to benefit from a day on the dyno

Have a Plan

We by no means go to the dyno with out a plan. Normally, we favor to maintain the plan easy.

Whereas we’ll sometimes spend the entire day on the dyno making a number of exams and pulls, we often discover it higher to spend lower than an hour taking a look at just some variables reasonably than an entire day taking a look at a number of them. The extra variables you’ve gotten in your testing session, the extra likelihood it’s important to make errors or misread your knowledge.

For instance, we might determine to work on dialing in our automobile’s ignition. Our plan can be to first baseline the automobile with the inventory ignition. Earlier than beginning, nonetheless, we’d examine the timing and report it. Then we’d set up any elements we wish to take a look at, often one after the other (extra on this later), and see how they do with the timing set the identical as inventory. As soon as we discover the very best mixture of elements, we’d modify the timing a bit at a time to search out the very best setting for energy. Within the above instance, we’ve outlined about an hour’s work and will in all probability make 15 to 30 pulls on the dyno. You’ll discover we’re doing nothing with the induction aspect of the engine—in a great world, we’d come again and do this at a unique session.

If we did do it on the similar session, we’d first do the entire ignition testing after which transfer on to the induction work (for which we’d have a separate plan). We’d not intermix any of those exams as they might confuse our knowledge and pondering.

Tune Your Automotive First

Opposite to what some folks might imagine, a dyno session shouldn’t be used for a lot “tuning.” About 90 p.c of your tuning ought to be performed earlier than you get to the store, with simply the rest dialed in on the dyno.

We’ve been to a number of dyno periods and dyno days the place automobiles go on the rollers and may’t even make a full pull as a result of they’re working so poorly. Whereas we’ve been capable of get them working proper on the dyno, we may have performed the identical factor with out this piece of kit and would have saved the house owners a bunch of cash.

In case your automobile has a drivability downside, a tough spot in its acceleration, or elements that you realize are weak, repair them earlier than you go to the dyno. Some folks will anticipate the dyno to magically establish these issues—and sometimes it’ll, however so may an excellent typical tuning session.

Rehearse Your Plan

After we’ve made our plan however earlier than we go to the dyno store, we all the time rehearse the plan at residence first. We set up all of the elements within the order we plan to put in them on the dyno. Once more, we often set up one half at a time and make sure the automobile nonetheless runs high quality after every set up.

Along with ensuring all of the elements match and work earlier than going to the dyno store, this rehearsal lets us be sure that we’re bringing all the right instruments with us to the store. It’s fairly cheesy to borrow instruments on the store, plus it’s simply going to waste costly time when you’re doing it.

Pack Your Elements and Your Instruments

On the dyno store, time is cash and good preparation will prevent each. Pack your elements and your instruments in an organized manner so as to simply discover them once you get to the store.

If doable, lay the instruments and elements out on a bench and even on the ground close to the automobile so as to seize each once you want it. Ensure you hold all of them collectively as a lot as doable so you possibly can deliver again every thing you introduced. No have to make the session dearer by by accident donating instruments or elements to the store.

Write Issues Down

We hold a pocket book that we take to each dyno session. We’ve our plan written out within the ebook.

Following the plan, we write down the baseline particulars of the automobile, together with issues just like the elements used and current tune-up settings. We additionally write down the climate situations.

Then, as we make every pull, we be aware the pull quantity, the adjustments we made to deviate from the baseline, and the outcomes—for instance, “down 2 peak horsepower,” “too lean above 4000 rpm,” and so on.

Whereas the dyno operator is hopefully placing comparable notes into the pc, it’s fairly good so that you can have a separate set to corroborate and examine afterward. Chances are you’ll discover the operator misinterpreted one thing or used abbreviations that make no sense to you.

Talk With Your Operator

Both earlier than or upon your arrival on the dyno, go over your plan with the operator. The operator might provide some recommendations: In the event that they’re useful, take them; in the event that they’re not, politely clarify that you simply’d like to stay to your plan.

Put collectively a mutual understanding of roughly what number of pulls you’ll be making and the way lengthy you’ll be on the dyno. That manner you gained’t end up dashing due to a miscommunication.

Then, after every change you make, talk about the outcomes with the operator. Once more, he might have some recommendations for you primarily based upon his expertise. Additionally, take a look at the information on the pc and ensure it is smart and the notes are right.

Make Your Baseline

The primary pull you make for the session is your baseline, and also you need it to be correct. We often make three or 4 baseline pulls and ensure that all of them graph out the identical. This shall be essential later within the session in addition to for future periods, because you all the time want an excellent baseline for reference.

If you happen to actually need to be ok with your session, you might even wish to return the automobile to its baseline set of elements and tune, then make a few final pulls earlier than leaving for the day to make certain it’s nonetheless the identical as the start. That manner you could be certain the climate situations or one thing else didn’t skew your knowledge.

Make One Change at a Time

There are occasional exceptions to this rule, however in the event you’re really making an attempt to check outcomes of tuning or elements adjustments, you must make one change at a time. If, for instance, you make three adjustments and lose a few horsepower, you possibly can’t actually decide what price you the energy.

Make Your Pulls

Consistency is a key a part of dyno tuning, so be sure to drive your automobile the identical manner for each pull. If you happen to’re making your pulls in fourth gear, be sure to speed up in control in the identical method every time. If you happen to skip second gear the primary time, skip it each time. If you happen to drop right down to 2000 rpm earlier than your acceleration begins the primary time, do that each time.

We often make two pulls, again to again, for every take a look at. In the event that they don’t repeat precisely, we don’t transfer on till we determine why and proper the issue. Then we repeat the pulls to verify we’ve obtained good numbers.

Count on Dangerous Pulls

It’s very seemingly that you simply’ll have a number of malfunctions throughout your session that make a number of of your pulls dangerous. Be a skeptic once you see extraordinarily good numbers and be an optimist once you see dangerous numbers. It might be that one thing threw off the information and it’s simply unsuitable. Repeat the take a look at till you’re assured issues are working correctly, then throw away the information from the dangerous pulls.

Get All of Your Knowledge

Don’t simply accept a number of graphs of your greatest pulls. Ask the operator to offer you all your knowledge. We often get graphs that examine some pulls in opposition to one another (for instance, baseline, greatest and worst, all on one sheet).

On the graphs, we’ll ask to have horsepower and torque vs. rpm—ideally with horsepower and torque on the identical scale—and we’ll additionally ask for graphs with air/gasoline ratio vs. rpm. Typically, we’ll ask for comparable graphs over time as an alternative of rpm.

As soon as we’re performed with the graphs, we’ll ask for a set of printouts of the numbers for every pull. We’ll get horsepower, torque, and air/gasoline for each 100 rpm. Lastly, we’ll get the entire knowledge on disk so we will plug them right into a spreadsheet later at residence if crucial. Your operator will not be keen about spending the time to do that with you and you might not really feel prefer it’s definitely worth the time or additional expense, however it’s. Your reminiscence will fade over time, so the flexibility to return to the recorded knowledge could be very useful.

Examine Your Knowledge

You could have discovered some issues at your dyno session, however you gained’t actually know till you’ve checked out your knowledge extra carefully. Learn via the graphs and numbers fastidiously and take into consideration what info is there.

Take into consideration whether or not you possibly can belief your testing: Does the information appear to help it, or are there numbers that simply don’t make sense? If you happen to’ve constructed an information library, you possibly can examine your numbers to earlier knowledge (or look on the web at different folks’s knowledge in the event you can) and see what else you possibly can glean.

Maintain a Knowledge Library

We’ve obtained knowledge from each dyno pull we’ve made. (Effectively, apart from a few of the clearly dangerous pulls we’ve thrown away.) We’ve made copies of the originals and we hold all of it organized in three-ring binders.

On the pages within the binders, we’ve included copies of our session plans and notes, and we’ve written feedback on the graphs and printouts. As our library has grown, we’ve been amazed at how typically we will use the information from previous session to make predictions and plans about future periods. It’s definitely worth the effort.

That’s a Lot of Work!

If all you wish to do is brag about how a lot horsepower your automobile makes on the wheels, you don’t actually need to do all of these things—simply go to the dyno and make a few pulls.

However in the event you’re critical about efficiency tuning, you’ll discover that these practices are useful, and also you’ll end up going again to the dyno time and time once more.