Anyone have desktop dyno be willing to get me a ballpark?

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Cal_gecko

Citron Yella!!
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I use a Mac, and there's no desktop dyno programs available for a Mac :(

I'm curious if anyone out there could get me a ballpark of what my engine might be making for HP .. ?

Engine is a remanufactured 360 - I'm assuming around 8.5:1 CR
Stock heads
Comp Cam XE268H cam (224 intake and 230 exhaust duration. .477 intake and .480 exhaust lift. And a 110 degree lobe seperation angle.)
Edelbrock Performer intake manifold
Edelbrock Performer (1407) 600 cfm carb
Hedman headers to 2.25" exhaust with turbo mufflers
 
No desk top dyno but I would say 320-340 hp @ 5300 rpm and 370-380 ft/lbs @ 4600 rpm. Stock heads is not enough info but this should get you close. I may be a little high though. J.Rob
 
Here you have a ballpark numbers from Comp Cams dyno: 320 hp @ 5000 rpm and 368 ft/lbs @ 2000 rpm.
 
My computer is screwed right now but RAMM is probably right on the money.
 
Thanks guys .. that's respectable I guess. Considering my 2012 Mustang V6 is 305hp, and it did a 13.81 @102 ... I just wanted the Dart to be close to that .. and after driving it, the Dart definitely has more torque... WAY more... and felt a bit quicker than the Mustang.. but traction will be a problem!
 
A real world 310hp at the flywheel would be about the top tune for that build in my opinion.
 
Mopar Muscle mag just did a dyno test on almost exactly the same set up and got 306hp and about 360 tq.
 
65cuda360 said:
His stock heads prolly have 1.88s, 2.02s on the Xs. Only 8 hp gain?
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Yep! And it'll only show up top the RPM scale.

Bakerlite said:
Desktop dyno is inaccurate.
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Generally speaking, yes and no, a lot depends on the exact inputs and the program also assumes a perfect running condition & optimum tune. While no program is perfect in its prediction of YOUR exact combo, it is a Ok program.

It is best as a learning tool.

I think RAMM has a great guess. I was thinking along the same line.
 
Bakerlite said:
Desktop dyno is inaccurate.
Click to expand...

No, those who input into desktop dyno are inaccurate. It can be spot on with all of the correct variables. How do you expect it to be accurate without head flow numbers? I can get mine right on the money with flow sheets.
 
See if you can read this.
 

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with what you stated I RAN THE NUMBERS WITH CAMQUEST..........which is close to the numbers some of the other guys ran

310 HP @5000

381 torque @3500
 
I got 301hp at 5000rpm and 354ft. lbs at 3500rpm. For as inaccurate as a lot of people say the program is, I've built things just like magazine articles and had my numbers come out within 5%.

It's just like the one poster above said it's only as accurate as the information your plug in. I probably have 200 different types of cylinder heads saved with all kinds of flow numbers, just so I am as accurate as possible.

I just use the program for fun anyways and if I was serious about half the stuff I build on it I'd be on the phone with a reputable builder for my project.
 
Yes it's inaccurate.. Straight away I can see a carb size of 600cfm @ 3.0Hg. 4bbl carbs are rated at 1.5 Hg. So if you trying to use a 600Cfm 2bbl, then your putting a "choke" on the engine.
8.5 :1 comp?? Really, my Briggs & Stratton lawn mower has more comp than that :)
What size is the "small tube header" 1 1/2 ?? 1 5/8 ?? 1 3/4 ?? What sort is the muffler? Free flow? Smog type ? with lots of back pressure. That program take a lot of inputs for granted.
I found EA pro was closer to the mark because it has a far better range of inputs.
That program always overestimates power readings, every half decent engine builder will tell you the same. But as they say, you get what you pay for.
 
Until you design something better, stuff a sock in it.
 
C'mon Rod, I'm just giving my opinion as an end user. Your comment's like saying
" Unless you've been President of the USA, then you shouldn't comment on politics"
Anyway, try going from a 4.030 inch bore to a 3.91 in your sim. I lost about 22 Ci but made 2 extra HP.
 
the user manual states the rule of thumb is that 95-105% of the exhaust valve diameter is considered a small tube header

120-140% of exhaust valve diameter is considered as large tube header.

It states that any mufflers simulated are high performance mufflers.

measure the actual compression ratio of a smog era 360, if it's over 9:1 I'll eat my hat, your hat and everyone else's hat.

I always think it's amusing that all the magazine articles tend to encourage everyone to think that an engine can be made into a 400hp+ fire breathing monster by bolting on an intake, some headers and a baby hydraulic cam, as if horsepower comes in chunks of 50 at a time with every mod.

You may have gained 2hp peak by going to a smaller bore, but the average would have been shot to hell because of the lower displacement.
 
Lots of good discussion here Cal. My quick scan of the earlier posts by guys that know there stuff, looks like really close predictions.

With that said.....Take her to the track :thumleft:. While paper numbers can give you a idea of power, they can also disappoint when the "real" numbers are revealed.
 
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