Any desk top dynos out there

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mod5v

mod5v

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Built this for my dirt track factory stock. The rules require 14"vacuum at 1200 and 175psi max cranking and .450" max lift Cam. flat top 4 eyebrow pistons 365cid max. cast iron exhaust 4412 holley 500 2bbl stock cast or aluminum intake.

360+.030 SP 405 pistons between 8.9 and 9-1 static comp.
EQ mag heads with LA manifold
diguised aluminum 68 340 intake P4532059
340 LH and early magnum dakota RH exhaust int 2 1/4 inch pipe
Bullet custom cam 286--230@.050--.3027 lift--110 separation---degree to 106 Hydralic per rules.
can anyone run this thru there program and give me a rough idea on HP--Torque ?
when racing runs betweeen 4000 and 6400 rpm.
Thanks
PS what happen if I install cam at 104?
 
I have a copy of Performance Trends Engine Analyzer Pro v3.9, I'll have a go and run it thru but will need some more specs from you - do you have more detailed specs on cam? Timing card info would be best. 1.5:1 rocker arms? This program relies more on numbers than picking parts out of catalog so I will take my best guess on stuff I'm not familiar with and you can correct me later.
Head data I pulled from Hughes website, using 2.02 Iron Ram specs: Hughes Engines
 
IMG_1528.JPG


The heads are just stock EQ magnum replacements 1.92in-1.625ex useing stock 1.6-1 rocker arms.
and thanks for doing this..Dan
 
This is more likely the kind of flow numbers i have.

Lift Stock Int 1.92" valves 1.62 exh valve.



IN EX
.100 58 59
.200 109 108
.300 168 145
.350 192 157
.400 212 165
.450 228 172
.500 236 177
.550 238 180
 
with specs given - 320@5500/348@4000 w/ cam at 106
 
Jeff webber said:
I have a copy of Performance Trends Engine Analyzer Pro v3.9, I'll have a go and run it thru but will need some more specs from you - do you have more detailed specs on cam? Timing card info would be best. 1.5:1 rocker arms? This program relies more on numbers than picking parts out of catalog so I will take my best guess on stuff I'm not familiar with and you can correct me later.
Head data I pulled from Hughes website, using 2.02 Iron Ram specs: Hughes Engines
Click to expand...

Performance Trends has good software...

My friend's son used it to design a cam for his 340 Duster and then another program to predict the ET and came within one tenth of what the software predicted....
 
I ran your engine and came up with the following:

- I think chamber size of your heads is 62cc, entering a couple of additional bits of info (-10cc for 4 eyebrow flat tops, .039" thick x 4.180" diameter head gasket, .050" down the hole @ TDC) I get 9.2:1 static compression, cranking compression still looks ok
- I used specs for a similar style Chev intake because it's in the program already
- If your max lift is .450" your combo exceeds this, I get .484" @ valve with .3027 and 1.6 ratio rockers

Best average torque calculated between 4000 and 6400 is with cam intake centerline at 108 degrees (2 degrees advanced, green=hp, dark blue=torque). As ground and installed straight up the intake is at 110 degrees (yellow=hp, pink=torque), your 104 degree centerline is 6 degrees advanced and does better below 4000 but loses out above (see red=hp, light blue=torque). Here is graph of the 3 cam centerlines:

Torque & HP Curves.png
 
Ignore the "Chev LT1 exhaust manifold" title in the exhaust system specs, used as starting point and forgot to change name.

If you see any errors in the specs let me know and I can make correction and re-run program. Note I don't have any air cleaner on carb so no restriction, I'm sure you're running one.

What water temperature does car typically run at? I've entered 165 which may be low in your case.

I modeled my 422" stroker for my car before it went on dyno, my predicted results were optimistic at higher rpm and actual exceeded prediction down low so something wasn't right in my model. Will play with model some more and see if I can get mine closer. I also found on dyno that I picked up power by taking a degree out of timing at higher rpm, was told this is common drag racing trick - use more timing to get car moving then pull a small amount for top end charge once chamber running hot and not needing so much. In my case was easy to do with MSD Digital 7, maybe you could try a degree out of total timing to achieve same thing in your running 4000-6400 range? Software doesn't get the same result as actual regarding timing with hot chamber.
 
Wow thats really detailed. Thank you. I run a 4"x14" high flow paper filter so probably very little restriction there also yes temps run anywhere from 170 at start of race to 220 at end. thank you for doing the diffrent advance/retard tests. Right now as the motor sets it is at 106. I know that the valve lift is a little high but they never check it at the track I race so I would bet most of the other regular cars there are over also. The cam was originally specked for stock LA 360 heads so when I was running those heads the lift was in spec.
Mostly I was wondering how close I was to the Intended power levels of the rules which are based off the late 60's chevy 350/350hp motor. I know that the chevys for the most part are out powering me so I need to step up my game a little. Thanks again for doing this. Dan
 
Hope it helps! Keep in mind my results are based off some guessing once you look past all the generated detail. If you want me to run anything else or make any corrections just let me know. I've got the file saved in case you wanted to try something. Can also send you the full PDF if you like, just PM me.
 
You can always use guesstimation.
Torque is a pretty easy guess. With 2bbl and manifolds probably gonna be around 1.15:1 tq:cid engine like that will peak about 4000 rpm so 420 @ 4000 and peak hp will be about 1500 higher and torque ruffly drops 90% at peak hp. So 378 lbs-ft @ 5500 put through the hp formula and you got 396hp @ 5500. But since your running manifolds and a 2bbl you could lower the peak rpm a bit and or the 90%.

Its no dyno program, can get you in the ball park.
 
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