I've built a few performance engines that did great on the street/strip, but I have yet to get a car ch***is dyno'd. Eventually i'm going to take the Rambler to get dyno'd. Yeah it's a straight six, but I want to tune it right and tune it on a dyno. If I can get it tuned up to it's original power level that would be fine by me. My question is this... what is proper dyno etiquette? I mean I don't want to just roll up there in the car and say "Hey can you guys tune this thing for me?" and not have what they need or sound like a complete idiot. Should I bring different jets, distributor advance springs, different plugs etc etc? Dyno operators: What do you guys prefer? What are some of the things you hate when someone brings a car to your dyno? How much of the tuning do you do, and how much do you prefer the car owner do? I know these questions are stupid-basic, but i've had these questions on my mind for years lol... Thanks...
having been a dyno owner for a few years i would say call (or stop in) first and see how each shop makes you feel after you leave or get off the phone. also look around or ask if your type of car piques their interest in any way. if not and they are tuning you just arent going to get as much for your $ imho. i know that of the three shops with ch***is dynos in my town i am the only one that caters to the customer, completely. that i think is really important. from giving the customer the opportunity to drive the car while on the dyno to allowing you to do your own tuning if thats what you want. alot of dyno owners get high and mighty about the fact they have one and expect you to heed their status. hence most do not allow the owner to drive the car or tune it on the dyno. i think this is ridiculous on so many levels, no one knows your car like you do. why would you want someone you dont know running your car at wot multiple times? another major factor that some do not consider when looking to dump some loot on tuning is the dynos loading capacity (or loading at all) and the dynos capicity in general. this might not sound like a big deal but consider the fact that the general dynojet you will run into probaly will not give you what you are looking/paying for. for instance, the common dynojet 248 is an inertia dyno. that means unless your car weighs the same as their drums your tune/time is wasted, and i believe without a proper load youre wasting your time. i have seen this firsthand many times over the past few years seeing cars come from inertia dynos. sure theyre good for #'s but thats not what youre looking for. also if the capacity is lower than your cars output youre wasting time. you said youre looking to tune a stock 6 so that should not be a problem. i would recomend hitting up the net so you understand the differences between dynos. this way you will learn about dyno mfgrs. fudge factors, what the #'s mean and what youre getting into. lastly, get an o2 bung in your header/exhaust 24" from the exh. port and 36" on a turbo car. that way you are ready for them to install their wideband sensor when you get there. i personally do not like tailpipe sniffers. too much delay in the information and they seem to vary based on maintenance. a wideband sensor is relatively cheap, replaceable, and pretty accurate. i usually only see @ 50 rpm delay when tuning and change mine every 30-60 days. dont forget the obvious checklist like checking all fluids, lugs, tire pressure, etc. my buddy joe has one at the bottom of this page of his website (i still need to do this). http://www.dohcvtec.com/pages/dyno/index.php
Dyno tuning is pretty stressful on your car. If something is going to go wrong, it is likely to happen on the dyno. It is important that your cooling system in particular be up to snuff. Since the car is not moving they have to cool it with forced air fans which may or may not be as efficient as natural air flow when driving... usually it is less. Check for leaks before you go. Dyno operators do not like leaky cars. Make an appointment to talk to the operator before you decide. If he's "too busy" to talk to you, go somewhere else. Make sure he understands your goals. Talk about the risks and what will be done to mitigate them. Clarify what work can and can't be done to the car while it is on the dyno. Changing jets and such is pretty standard.
Thank you very much for the advice. It's cool to hear from an actual dyno owner too. It's too bad you're not down here in Austin, it would be great to do business with you. Do you guys know what average going rate is for dyno time? Maybe i'm really unrealistic... but with a stock six i'm not going to drop a grand on this motor for just a couple dyno hours to maybe pick up 15ish horsepower. I might just have to save the dyno for a car that's got some major cajones. How long does it take to dyno and tune a car?
Our shop only has an engine dyno, but one of the biggest mistakes is when the customer comes in and expects a huge number from a combination that has no chance of making it. Seeing as how you're only looking at a stock 6, don't be suprised if it puts down a very small number. Don't accuse the dyno or the operator of being wrong. Go in with a conservative number so you can be suprised when it makes more. We've had alot of lunches bought because of dyno bets... Good luck!
Be sure your dyno operator talks to you about correction factors. Most should correct to standard day at sea level...
Things to look at first , check for va***e leaks . replace pcv .change oil .look at exhaust leeks .also replace plugs and filter . nothings worse than several weak parts combined to lower your #s and performance before you even start . an important thing to check and this is more important on posi or locker rear ends than open rears is, even up the tire roll out on the rear tires it robs hp and its a bunch ,less than 1/4 inch is good . I think that once this is all done the time spent would be on dist and carb . since your in south tx i can say that we here in dallas pay just under 500.00 for a half days dyno time . you will need to hustle to get what ever you want done so go prepaired .I take a small box with tools ready for the specific jobs at hand ,this includes parts .good luck .c
If your dead set in using a dyno to tune your vehicle,im all for it. Finding a operator who uses it to its potential is not so easy.Matt seems to be right on with his explination. A dyno is a baseline to real world conditions,depending on the operator is how close to real world you get. Im a drag racer and my pesonal experiance with a dyno is limited,But i know what i have seen more than once and it is more common than not. Lean is mean,in order to get a big # on paper the tune is a little on the lean side,so drivability when its off the wheel is focused on hp rather than torque.Off the dyno it goes like stink wot and at 5k rpm but its real snotty getting there and around town. Yes im all about using a wide band and placement but for your situation,you may not need to spend time and money for braggin rights on a dynosheet. Use a 1340 dyno,get some plugs,a timing light and a few jets and make some p***es.If you never drag raced before a simple rule to tune by is MPH is horsepower and ET is driver.Tune for your mph.At first you will see et all over the place but mph pretty much the same. For 500 buck of dyno time i can make a lot of p***es down the strip and have a good time while at it.Knowing the changes you made and the results from doing it is reward enough.If something is going to blow,might as well have some fun while doing it. Dynos are a great tool,but its just that a tool. The person operating it determans the outcome,the same thing goes with flow benches and other tools that help us with important information. If your looking to get your car to run to its full potential,race it and you will learn a bunch along the way for shure. Dynos allowed racers to find gains that we would need 1000s of dragstrip p***es to find esp the tuneability in the efi world but in your case i thing a good p*** will put you in the right direction. Either way good luck on your quest........Gary
Ask the operator if he knows your carburetor well - he can't diagnose flat spots if the circuits are strange to him. He must know Holley 4150 and AFB - does he know 97, Rochester B? Stromberg WW? Tire pressure checked, oil changed, all fasteners tight, clean filters, &c. Bring with you: » Tune-up specs (valve lash, spark advance, &c.) » Spare jets, metering rods, power valves, wire gauge drills, &c. » Carburetor gaskets » Air cleaner or velocity stack choices » Normal and cold heat range spark plugs (several sets so you dont have to clean them) » Ignition points, plug wires and condenser » Exhaust pipe or collector extensions in small increments (2, 4 lengths), hangars, clamps and hardware » Any other parts to test (advance springs, cam advance key) » Wrenches » Gloves and rags » Colder thermostat » Log book
I recently restored a 340 Duster for the original owner. WE kept it stock looking but took some liberty's with the motor. Aluminum Heads, Cam, Manifold, Carb, Headers & Exhaust etc. When the car was done it felt real healthy and both we and the owner agreed that it was faster than before. To me something still didn't seem quite right. I called Joe Jill at Superior Automotive about a Dyno Tune session. We set something up and with this being a fairly common set up, he had jets and advance springs in stock. When they finished, they had "found" 120 HP and charged us a total of $350.00. Well worth it!
After hearing what dyno time costs, I don't think it's worth it for a stock 6 at this point. I'm going to do the drag strip test and tune from there. If I get serious with mods and install a bunch of speed parts i'll go to the dyno. For a stock car I just paid 350 bucks for... eeeh... not ready for the dyno just yet. hotroddon- Thats really cool that they found an additional 120 horsepower. If this thing were modded 8 like that 340, i'd definately get some dyno time in. To be honest I don't think this engine would put down 120 at the rear wheels. It sounds like i'd spend a couple hundred bucks and only pick up 20ish horsepower IF THAT. A couple hundred bucks buys some nice speed parts for this ol' Rambler.... Thanks for all the answeres to my questions. I've been mulling this over for years.
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