Dyno Tuning?

71Duster said
It's a new engine see -What would you do post-

It just doesn't have anymore go then the worn out 340 it replaced. What sort of questions/answers should I have ready when looking for a chassis dyno?


Read what I responded again. I didnt say flog it on a dyno. IMO, you have a problem you havent found yet. That means either you havent looked in the right areas, or it's easier (not cheaper) to not look and just tune. SOmetimes a running engine isnt a good thing. Because once it fires, one doesnt want to "take a step back" by pulling things apart. But, if there is a problem, you can stay dissapointed, try the easier avenue of throwing $$ at it with easy swapped parts, or maybe test the stuff, or toss money at someone else testing it for you and repair as needed. I really think you need to have it checked by a pro. leakdown test show how good the engine is at holding pressure and where things are leaking. Compression tests show how much potential power is there. Inspections give physical measurements that can be compared to "right" or "not right" values. When I worked at a dyno place, we'd see all kinds of guys who wanted the car "tuned" on the dyno. It's not cheap. there's usually a hookup fee that includes 3 pulls or one hour's time, then an hourly rate after that. Id watch as the cars were tied down, and the guys would work on them, only to disaapoint the owner who knew "the carb's worn out" or "it has oil on 2 plugs when I checked". So the $150 setup, and the $75/hr for 2 hours after (you get charged for time, whether or not the car is being pulled) and they leave disappointed and $300 lighter. The time to find problems is before the dyno, and then you use the dyno to adjust the last few items. If you use the dyno to diagnose a low power problem, you're looking to spend twice.

As you find different places, you'll find different dynos. Some are "friendlier" than others (meaning give higher results), some use a roller in the floor, some use individual power absorber heads that bolt on the hubs, some have data aquisition, some have fast rate O2 sensors, some dont. You want someone who is out to help you, not give you a hp number. Preferably someone a friend or club member has used and got good results. They should have been doing this for at least a year, the shop should be neat and clean, and they should be able to test air/fuel mixtures. There will be a charge for weld in bungs in the header collectors for that. It's worth it IMO. The tailpipe O2s are not as fast reacting and get sooted up fast, so they can give false readings. Also, make sure you understand thier charges and how they are applied. Is it by the hour? Does that include carb adjustment time at that higher rate? How many pulls are included in the base charge? Can you also work on the vehicle, or do you have to stand back and watch? Can you provide your own parts (gaskets, jets, MSD curve stuff, etc)? All questions that should be asked. I like to go and watch another car being tested. If you get nervous because it's not tied down well, or you dont see fender covers or clean uniforms/hands, or there's stuff piled all around the car, or you just dont like the way the guys tests (like back to back pulls with no cool down, or simulating a full dragstrip pass..I hate that), find another place..Find somebody else.