Desktop Dyno - Please rate this motor...

[66P51GT]

Being a Mac user, I don't have access to the hord of PC software that is available. I was wondering if one of you can pass back HP and Torque estimates for this engine build?

302 Standard Bore
Stock Pistons
Boss Rods (stockers refitted with 7/16" rod bolts)
9.5:1 Compression (estimate)
Crane 2131 Roller Cam
.050 Dur Lift
Intake 214 276 0.513
Exhaust 220 282 0.529
Dart Windsor Jr. Heads (iron)
58cc chamber
180mm runners
1.94 Intake
1.60 Exhaust
Full Roller Rockers
Edelbrock RPM Intake
Holley 670 Street Avenger Carb.
MSD Distributor
MSD 6A
MSD Wires
Mac Long Tubes
Dynomax X-Pipe
Flowmaster Delta 50s

Motorsport T-5 Tranny
4.11 8" Posi Rear

Not sure if you need any additional information.

Thanks in advance,
-Chuck

 

[larrendeuce]

I have a program that can give an estimate, I'll post the numbers when I'm done.

 

[larrendeuce]

I need the lobe center angle, intake centerline, and the intake and exhaust duration of the cam, when I used the numbers you posted it came up invalid.

With a performer RPM cam, Single Plane Manifold, 670cfm carb, windsor jr heads, long tubes and mufflers, and 9.5 to 1 compression

385 hp @ 5500 rpm
396 ft lbs torque @ 4500 rpm

its a pretty general program I can't input intake manifold flow numbers or exhaust system specifics like midpipes.

 

[proxses]

I tried it in Performace Trends engine analyzer 3.2
I got:
348hp at 6500
321tq at 5000
Lobe separation of 112, dual plane manifold (at least the program said the RPM was a dual plane), 34" long primaries, and a standard duel exhaust.
On open pipes it made:
380hp at 6500
346tq at 5000
Both had very broad torque curves.

And is it possible that it is the Crane 2031, and not the 2131. If it is the 2131, then the lobe sepatarion might be different. But I couldn't find any info on the 2131.

 

[66P51GT]

Thanks for the replies. I was looking for a flat torque curve with ~350HP. Looks like I'm right in the ballpark. I'd say that's pretty good for $1,807 motor and $657 exhaust!!!

Cam Correction: Crane 2031 (thanks proxses)
Lobe separation: 112*
Performer RPM: Dual Plane
Intake Centerline: ??? not sure what this is

-Chuck

 

[proxses]

My program lists the intake centerline at 107*, for anyone else, who wants to run numbers.
I ran numbers at 112* intake centerline.

 

[Black331Stang]

larren..do u have that mustang specific dyno program?

 

[66P51GT]

I averaged the numbers and came up with:
371 HP @ 6,167 RPM
354 TQ @ 4,833 RPM

If anyone else chimes in, I'll be able to better refine the initial estimate. After the engine is built, I do plan on getting on a dyno to measure RWHP. It will be interesting to see which program is most accurate.

 

[ninjacoupe]

I'm in the same boat here. MAC computer's just don't have the support that everyone else gets.

 

[Roger Ramjet]

Well, that program is worth exactly what it cost. I loaded it with real head flow data and cam events from a Harley motor I did for a friend of mine last year. I have real carb flow numbers and rear whell dyno numbers. I designed the engine on Performance Trends' Engine Analyzer Pro - it predicted 135 HP at the crank. A DynoJet dyno measured 121 HP corrected at the wheel. That's an 11% loss through the drive train - very normal. The Desktop Dyno program shows less than 100 HP.

The induction flow element seems to be the weak link. Who has flow numbers at 1.5 In Hg? No matter what I put in this entry, the result never went over 100 HP.

If you want to get serious about engine modeling, go to: http://www.performancetrends.com/