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View Full Version : What dyno do you like?



HaxbySpeed
12-29-2009, 03:27 PM
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
12-29-2009, 05:37 PM
DTS, DTS, DTS..............Land and Sea are toys.............SF are somewhere in the middle.

MikeyFIN
12-29-2009, 05:45 PM
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
12-29-2009, 05:55 PM
Siemens AC dynamometer

Lee
12-29-2009, 06:13 PM
Avl

Mrhorsepower1
12-29-2009, 07:14 PM
Superflow

imco offshore
12-29-2009, 08:24 PM
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
12-29-2009, 08:27 PM
5250

MikeyFIN
12-29-2009, 08:48 PM
5250rpm is where ft.lbs and hp meet, the other going up the other down..

MikeyFIN
12-29-2009, 08:49 PM
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
12-29-2009, 08:49 PM
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
12-29-2009, 08:51 PM
Thats why Iīm selling my rolling road dyno for cars...not enough use to make bucks...

MOBILEMERCMAN
12-29-2009, 09:21 PM
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
12-29-2009, 09:31 PM
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.. :cheers2:

MikeyFIN
12-30-2009, 07:34 AM
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.. :cheers2:

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
12-30-2009, 01:53 PM
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. :eek:

Mrhorsepower1
12-30-2009, 01:59 PM
'
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
12-30-2009, 02:32 PM
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 didnīt 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 itīs 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 hasnīt 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... :eek:
Dunno about that but I try my best and double or triple check a lot.

MikeyFIN
12-30-2009, 03:14 PM
some interesting reading from my favourite mag...

http://www.circletrack.com/techarticles/139_0303_dynameter_dyno_tech_types_overview/index.html
http://www.4wheeloffroad.com/techarticles/engine/131_0610_engine_dyno/the_tune.html

Brian41
12-31-2009, 10:46 AM
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

skaterdave
12-31-2009, 11:09 AM
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. -

MR, how do you apply the load to the engine on your dyno.

my engine guy has an Inertia Dyno, in this design he has a fixed weight which is excellerated. the computer reads the time in which it takes to excellerate the weight along with reading all the other info. since it takes torque to move the object, this is timed and thats how you get HP.which it is also my understanding this is how much of the high end endurance builders test engines(nascar).

Mrhorsepower1
12-31-2009, 11:30 AM
Looks good Brian! :cheers2:

Mrhorsepower1
12-31-2009, 11:32 AM
MR, how do you apply the load to the engine on your dyno.

my engine guy has an Inertia Dyno, in this design he has a fixed weight which is excellerated. the computer reads the time in which it takes to excellerate the weight along with reading all the other info. since it takes torque to move the object, this is timed and thats how you get HP.which it is also my understanding this is how much of the high end endurance builders test engines(nascar).

Superflow use a water brake to apply load.

Brian41
12-31-2009, 12:01 PM
Looks good Brian! :cheers2:

Thanks, We have not met each other I have heard a lot about you as we are only a couple hours from each other, I am in SE Michigan 21 miles north of Toledo. Sorry about the SF comment but before I bought the DTS I went to SF and spent 2 days with them and then went out to California and spent time with the guys at DTS. I am not saying SF does not make a good system but at the time they did not offer a docking system and I found DTS's acquisition system easier to read plus the 2000 HP capability without upgrades.

HaxbySpeed
12-31-2009, 12:53 PM
Thanks for all the input guys. I'm not trying to reinvent the wheel, just save some time and money. I usually dyno around 20 engines per year. The facility I use is not set up for wet exhaust which results in a lot of extra tuning in the boat. On EFI stuff there is often times where it would be nice to leave the motor on for a couple days to work stuff out. I break in everything on the dyno, even if its only 300hp. Anyone who's spent 40+ hours rigging an engine and installing it in a boat only to find a small leak somewhere knows the value of dyno testing first. Also Jeff, it's not so much the dyno operators experience, it's his tuning ability. I certainly don't know even close to what some of the guys on here do about tuning, but being crew chief for a six second drag car for about seven years now I get lots of practice..

Have a great New years everyone! :cheers2:

dykstra
01-08-2010, 05:38 PM
:driving:

Brian41
01-09-2010, 09:58 AM
:driving:

Whats all the analog looking gage things........... its 2010

mdgperf
01-09-2010, 11:51 AM
I have owned
a land & sea dyno since around 1996,dual rotor i set it up for what i work on the most 500-800hp marine engines,I set it up to use water cooled exhaust and all the marine hardware so its true marine hp ratings,the brake holds well on sweep and steady state pulls,I pull my water from a 1000 water tank and keep refilling as i am running,during a 30-40 minute break in water will start to get low works great for my purpose,Land and Sea builds dyno to be more affordable than the superflow and dts system and has put a lot of dynos in shops that couln't justify spending the big bucks on the dts or superflow,my set up works great on the 500-800hp range i have dyno 1100 the brake held it but got very hot,with more water volume going into and out of brake could work better on the 1000-1300hp stuff but i really don't work that hp level much

dykstra
01-09-2010, 05:08 PM
Whats all the analog looking gage things........... its 2010

It's Peoria, Illinois!!!:bump:LOL

tunertech
01-10-2010, 11:30 PM
save your money and send your engines to those that have done it for years.

www.mefituning.com

HaxbySpeed
01-11-2010, 12:44 AM
Sure I'll just crate em up and send them to you. I'm sure that will save time and money...:rolleyes: