Desktop Dyno. . 256hp/295lbft

[Mr. Spock]

According to my Desktop Dyno software a 3800 should make 256hp and 295lbft of torque (at the flywheel) with a GT comp cam, Thrasher heads (with the 1.9 intake valves), small tube headers and descent exhaust. Does anyone have a similar setup that could verify this. If possible with real dyno numbers. What I am really wondering about is just how accurate the Desktop Dyno is.
If this is at least somewhat accurate I will likely be keeping this engine. Thats pretty good numbers for the money. a bit off Lt1 power for the 6 price tag hmmm. . .

[Bliggida]

I have never seen anyone ever make the power that desktop dyno claims. Either come up short or overshoot it by a large margin. Just use desktop dyno as a computer toy, instead of a hot rodding tool and you have better results. Its just a game.

[WickEdSix9838]

its not very accurate because you cant enter enough information to give the right numbers...i have a program call Engine Pro that cost $300 at home and you put in cam durations, valve sizes, how much the heads flow, bore, stroke, rod length, head gasket thickness, chamber CC's, deck height, intake flow, percentage of intake flow to how much the heads flow, and many more things and it figures around 10-20 HP within what the motor will actually make at the flywheel, then it also gives you what size headers to run, length of the primary tubes, what size collectors, how much lift to run on the cam, what length to make the intake runners if you build a sheetmetal intake, it also gives piston speeds in 100 RPM increments, its a really cool program but is expensive...

[Redsix]

Looking at something like 220 to the wheels maybe.

[navyblue2000]

1.9 rockers with a GT cam would give some insane lift...better find some tall valve covers [img]tongue.gif[/img]

[Dominic]

Its *very* easy to put in the wrong numbers in dd2k and get the wrong answer. Its also not accurate to 1hp either, more like +/- 20hp, and the variances in *exhaust* setup make a big difference... and I am not sure if it should or not.

Please be careful, its easy to get the wrong number if you dont know PRECISELY what you are doing with it. And even still its iffy. Never forget its theoretical power too and its before losses from accessories.

[Mr. Spock]

1.9 intake VALVES. Yeah I didn't think that it was too accurate. I definetly did think it didn't have enough parameters to be worth a damn. It's still a little fun to play with.

[ April 12, 2003: Message edited by: Mr. Spock ]</p>

[Takumi Fujiwara]

As well as our OHV engines produce different power than OHC engines. The desktop dyno is a waste of time, Go spend the 50 bucks and dyno the car.

[malloynx#2]

wel seppo runs the gt cam and he is trapping at 97mph in the 1/4.. he has to be making over 250hp..

[black34v6]

damn. listen to all the negative replies..

Desktop Dyno is not that bad a tool. it depends on how much info you have and how accurate it is.

ive put the 3.4 #'s into DD2k - and i come up with 156 hp @ 4500 rpm / 202 tq @ 3500 rpm. its still off yes, but not by as much as you guys say.

even with all the numbers i put into it for the 3x00 swap - it came out to 207 @ 5000 / 245 @ 3500 (very very close to what i dynod - 200 @ 4833 / 244 @ 3259).

It's Tiago and my reasoning that DD2k is great for N/A motors, but when it comes to Forced Induction it just doesnt handle very well. the other issue is that while everyone has put all the info they could find into it (tiago and i - i think - have the most accurate info for the 3.4L N/A engine and NRT engine), no one has really calculated the CC size - and last i looked DD2k reports it at like 69.something. the CC in the iron 3.4 head is 53 something, so even there you are off.

so instead of knocking the program, realize it is a very advanced tool and treat it as one. dont be childish and just be like "it doesnt work - its a pile of crap" just cause you dont know how to use it.

-R

[OneQuickV6]

YEP, just like the last guy said...can be a good tool to get a give-or-take result from say a cams wap before you do it...once you get all tghe parameters set right, it can be a very good tool. There's a guy who runs one of the biggest shops in town here, and he won't hardly do a cam swap or anything performance orientedt until he logs your car into DTD.

[Tiago]

DD2k was right on my stock numbers, but now its wayy of....

[Dominic]

<blockquote>quote:</font><hr>Originally posted by Tiago:
DD2k was right on my stock numbers, but now its wayy of....<hr></blockquote>

Yeah its terrible for FI, but n/a its wonderful for cam design if you just want to see what differences things make. ;)