yes i have but if the dyno is calibrated correctly and used for it,s intended purpous it is a very valuable tool.

Its General Question and Answer, and if someone asks a question, there will always be many people that have the "answer" or input on the question. There will be different opinions, there will be facts, and there will be wrong information. fi you expect that everyone will share your opinion or the same experiences that you have then you are going to have a constant battle on the internet posting information. It doesn't matter what you post it will see some sort of criticism or disagreement from someone. Dyno may be a reference, or data, or whatever you want to consider it, but it isn't a hard data point, if it was then you would be able to take any engine to any dyno in the country at any time and it would spit out the exact same figures every time on every dyno.

I 100% agree, its a priceless tool honestly. But the data that comes from it could be skewed one way or the other is all I am saying, and that number can be skewed a significant amount depending.

We have the same mind set here, we want the dyno to simulate "in the boat" atmosphere as much as we can. Unfortunately not every dyno is set up that way, calibrated that way, or calibrated frequently for that matter.

i will add that the tech that esist today for dyno,s takes all the correction information and imputs it directly to the machine,s computer,then it self corrects for all the things that effect the reading.when it comes time to choose where to take your engine for dyno tuning it is wise to ask questions before before spending your hard earned money.edit in-this is why i do all my dyno work where i do,they have state of the art equipment and there duno spits out facts,it,s not a wish o meter.

At work I just tap on the glass till the needle reads what I want. Same thing then, I guess.

Mark, as BS aside, I am excited as heck for you, to get these engines in the boat. We know what it ran with the 420 combos, and I think you are gonna be extremely happy with these two new engines in your boat. You did an excellent job on last years interior makeover, and now you're gonna have some sweet engines to push that boat to speeds it's never been to. You did it right. You didnt cut corners, trying to reuse old pistons, rods, half azz machine work, reusing old heads, and what not. You spent some coin, but I feel you did it right. It makes life much easier for the guy doing the assembling and what not, dealing with someone who's willing to take the steps needed. I've seen way to many guys want to cut corners, and not only does it make life hard for the builder, it usually comes back to bite everyone in the azz.

I would like to come down with Mike to help dial it in on the maiden voyage if thats cool with you guys.

That would be my assumption as well. If you simply walked up to a 177, and a fresh tight 871 sitting on a bench, and spun each pulley by hand, theirs no question which one turns with less effort.

In an equal comparision, if the 8-71 is producing an extra 100HP up top, and gave up 30ftlbs at 3500 to the 177, the 8-71 combo is still going to make for a much faster boat. It has been proven many times on merc's 575sci. Replacing the small 256 blower, with an 8-71, even at the same boost level, has netted significant speed increases, with no other mods, and guy's who've done it, have been very pleased with the results. Just as I was, when replacing the 177 with a 250, and replacing the 250, with a 420. Each time i upgraded, I saw gains, which is the ultimate goal, is it not?

In a scenerio like Paytons, maybe down the road sometime, he will get an itch to go even faster. He has a solid foundation to work off of now, and in the future, if he scored a deal on some blowers, he'd be able to bolt them on and probably pick up an extra 5mph or more. But at this point, his current builds have met and exceeded his goal, and should make his boating experiance, alot more fun than last year.

joe,since you offered to help i am going to hold you to it,we may even have a few beers when we are done.

Yes the dyno that we are using is the dyno that my builder uses for all of his motors including the motors in his race boat, if anything its on the conservative side. The shop where the dyno is use it predominately for circle track cars where it is crucial for the dyno to be dialed in. They have a test mule that they run and calibrate the dyno constantly.

Performance in the boat is what matters, and tells all really, so absolutely.