What dyno do you like?

[HaxbySpeed]

I'm looking to buy an engine dyno and was hoping to get some input from the experts. Anyone using Land and Sea stuff? Their pricing seems good. I've only used SF and DTS. It needs at least 1500hp capability. Thanks, Alex

[Brian41]

DTS, DTS, DTS..............Land and Sea are toys.............SF are somewhere in the middle.

[MikeyFIN]

Gotta agree here,, DTS is great, L&S forget it, Im myself putting together one with an eddy current brake...saves a lot on the engine.
Looking into DTS4000G Data Acquisition System or Custom made here.

[rockfish71]

Siemens AC dynamometer

[Lee]

Avl

[Mrhorsepower1]

Superflow

[imco offshore]

i have a dyno question...is it so??? torque = hp @ 5200 RPM.S ON ALL ENGINES
#2 can all dyno sheets be manipulated to show what ever you want??

[MOBILEMERCMAN]

5250

[MikeyFIN]

5250rpm is where ft.lbs and hp meet, the other going up the other down..

[MikeyFIN]

i have a dyno question...is it so??? torque = hp @ 5200 RPM.S ON ALL ENGINES
#2 can all dyno sheets be manipulated to show what ever you want??

'
Not sheets but dyno runs can be fiddled with..Sweep tests show a tad more than step tests.
Well actually yes Sheets can be fiddled too... just change the parameters to show wrong on the sheet...

[jeff1000man]

SUPERFLOW... Land and Sea are toys. Your forgetting one thing though. It takes years and years of experience and 1000's of pulls to finally understand what the dyno is telling you and how to translate the data into useful info.

I looked into buying one a couple years ago, but your time and money is better spent doing research into what has allready been done, and finding a good dyno operator who knows what he is doing.

I have run across a lot of guys with dyno's, but I have only found 1 really really good one and one who is pretty good. The rest are just guys who have expensive toys and are learning to use them at your expense.

Good luck with it if you decide to buy one. If I had the room and the disposable income, I would have one, but for what a couple sessions cost, you can't beat taking your engines to a good dyno guy. And I usually learn a couple tidbits of info when you I am there since there is allways a lot of engine guys around talking about things that they have tried in the past.

[MikeyFIN]

Thats why I´m selling my rolling road dyno for cars...not enough use to make bucks...

[MOBILEMERCMAN]

Its tedious to verify the different variables. Weighting the fuel, measuring barometric pressure, maintaining consistent air supply temp.....

I witnessed a guy in Jersey who took the time. He did the IROC engines for Penske. They had dynos too but, Johnny knew how to use his.

[HaxbySpeed]

i have a dyno question...is it so??? torque = hp @ 5200 RPM.S ON ALL ENGINES
#2 can all dyno sheets be manipulated to show what ever you want??

Torque x rpm divided by 5252 = horsepower
it doesn't matter what the engine is that's just how it's measured. Horsepower is the result of torque and rpm..

[MikeyFIN]

Torque x rpm divided by 5252 = horsepower
it doesn't matter what the engine is that's just how it's measured. Horsepower is the result of torque and rpm..

P= W/t=(m x a)/t

P=Power
W=work
m=mass
a= a-c-c-e-l-e-r-a-t-i-o-n
t=time

[Mrhorsepower1]

i have a dyno question...is it so??? torque = hp @ 5200 RPM.S ON ALL ENGINES
#2 can all dyno sheets be manipulated to show what ever you want??

Yes the dyno is only as good as the operator. An un honest builder could inflate corrected torque and horsepower figures. All this will do is hurt them in the long run when the boat or car doesn't perform and run the speed it should with X amount of horsepower.

[Mrhorsepower1]

'
Not sheets but dyno runs can be fiddled with..Sweep tests show a tad more than step tests.
Well actually yes Sheets can be fiddled too... just change the parameters to show wrong on the sheet...

Actually a step test is more accurate when you want to know figures at a given rpm. My endurance engines I run step tests. With step testing, The engine is ramped by 100, 250, 500, 1000 , ect rpm and held there for approx. 3 seconds on each step . This allows more accurate torque and HP numbers at that rpm. With Sweep tests or acceleration testing the numbers will be a bit lower due to the time the dyno has to measure. On extremely high horsepower Drag Racing engines acceleration testing is more appropriate. -

[MikeyFIN]

Actually a step test is more accurate when you want to know figures at a given rpm. My endurance engines I run step tests. With step testing, The engine is ramped by 100, 250, 500, 1000 , ect rpm and held there for approx. 3 seconds on each step . This allows more accurate torque and HP numbers at that rpm. With Sweep tests or acceleration testing the numbers will be a bit lower due to the time the dyno has to measure. On extremely high horsepower Drag Racing engines acceleration testing is more appropriate. -

Sweeps are just the ones IMO to make the customer happy.
I never did sweeps..steps only maybe thats why I never got the job to take off... being too honest and conservative.
Thenagain I didn´t have an inertia dyno either which are optimistic compared to a brake one.
At least on the rolling road dyno, right?

Funny thing is that I did a boat engine for a guy and he asked how much does it have?
I told the numbers @ rpm and said it´s a tad rich.
He took it to one guy with an engine dyno and first pull they took was the exact number and RPM and the operator told this hasn´t happened for a long time... played with it for 2 hours and took it a bit leaner and gained only 3 hp...
Told the customer when he heard who did the engine Yes I heard thru the grapevine he builds good engines...
Dunno about that but I try my best and double or triple check a lot.

[MikeyFIN]

some interesting reading from my favourite mag...

http://www.circletrack.com/techartic...iew/index.html
http://www.4wheeloffroad.com/techart.../the_tune.html

[Brian41]

If you are considering buying an engine dyno do not forget that the dyno purchase is just the down payment of the entire system needed to achieve accurate and repeatable pulls. The proper cell construction is as important as the equipment you buy. I bought my DTS dyno 8 years ago and soon realized I was in the wrong location for what I was about to do (neighbors). It took me 3 years to find and purchase a property that was better suited for the dyno operation and another 4 years to finish the cell. Now the equipment is new in box and 7 years old.... guess what I had to buy all new data acquisition because of internal problems and found out the old stuff was obsolete before I did my first pull. DTS gave me a deal at $5000.00 but it still hurt with all the money spent putting this together and with the first engine ready to go I could not stop. I built the cell myself and still have over $100K invested. Would I do it again? I look back at all the engines we have done over the past 30+ years and the time it took to tune and correct the engines in cars and boats I would be 5 years younger so YES I would.

MikeyFIN if you want good reading on dyno's get "DYNO Testing and Tuning" by Harold Bettes & Bill Hancock

Here are some pics of my dyno