Desktop Dyno 2000 and Head confusion

[Guest tony78_280z]

I’ve been playing around with Desktop Dyno 2000 to determine the direction I should take when I begin to modify my motor. It shows no improvement in torque or horsepower between Low Performance/Pocket Porting and Wedge/Pocket Porting, Stock Valves in the heads selection. What gives? I thought that the wedge style (vortec) would increase HP and Torque. According to this dyno there is no difference

 

 

For the same price I could order new iron Vortecs assembled and intake manifold or I could find some aluminum low performance from the junk yard and rebuild them. Either would cost about the same. If the HP / Torque is going to be the same then I would like to go with the lighter aluminum heads.

 

 

Dumb Tip for the day: Get the ignition system correct with new plugs and wires before bothering tuning a carb. I got my holley all tuned up, turns out my plug wires were a lot worse than I had thought. A tuned carb to bad wires = retruning carb.

[grumpyvette]

first thing you need to realize is DD-2000 is a very poor software for prodicting engine output, but it does have its place as its quick and easy and surprizingly accurate on the PEAK numbers and where in the RPM band those PEAKS fall PROVIDED you enter the data correctly

 

WANT BETTER RESULTS??

 

http://www.auto-ware.com/software/eap/eap.htm

 

I use this, in the shop.....it costs ALOT MORE MONEY but its BETTER SOFTWARE and it should be for Your price $459.95

 

want to predict your potential hp from the cylinder heads flow numbers?

I can give you a quick and dirty formula,.flow at max lift x # of cylinders x .257= hp

not its not exact but it is a good guide that will get you SURPRIZINGLY CLOSE on most STREET STRIP engines

[Guest tony78_280z]

first thing you need to realize is DD-2000 is a very poor software for prodicting engine output' date=' [b']but it does have its place as its quick and easy and surprizingly accurate on the PEAK numbers and where in the RPM band those PEAKS fall PROVIDED you enter the data correctly[/b]

 

WANT BETTER RESULTS??

 

http://www.auto-ware.com/software/eap/eap.htm

 

I use this, in the shop.....it costs ALOT MORE MONEY but its BETTER SOFTWARE and it should be for Your price $459.95

Right, Like I can afford that LOL. I "Borrowed" DD2000. All other data being equal in the program, Even the PEAK numbers you describe are the same for both type of heads.

[grumpyvette]

if the flow thro the ports is the same or close to the same at the max cam lift, the results will be similar and DD-2000 is just a way to get a quick estimate , theres tons of factors it fails to account for, it, (dd-2000) makes a educated guess, its NOT reliable in its exact results

 

BTW you may find these useful

 

http://users.erols.com/srweiss/tablehdc.htm#Chevy

 

http://chevyhiperformance.com/techarticles/41598/

 

http://www.kendrick-auto.com/head_flow_figures.htm

 

http://www.nastyz28.com/2gcog/cylhead.html

 

http://www.geocities.com/z28esser/headcomp.html

 

http://www.dw1977.cz28.com/photo2.html

[Guest tony78_280z]

Great info as usual. You always got the hook-up wit' da' links! The flow @ lift information is very interesting.

 

I think I would be happy with any of the following. at the bottom of the list is the bow ties. They don't look too bad, and might be just the sort of thing I'm looking for, Unless the small chamber size will get my ratio higher than 9.5 !! I still wanna run on cheaper gas.

 

Vortec L31

PORT SIZE: 170

 

CHAMBER: 64cc

 

VALVE SIZE: 1.94 / 1.5

 

PRICE: $400.00

 

FLOW@.100: 70 / 48

 

FLOW@.200: 139 / 101

 

FLOW@.300: 190 / 129

 

FLOW@.400: 227 / 140

 

FLOW@.500: 239 / 147

 

FLOW@.600: 229 / 151

 

 

GM LS1

 

PORT SIZE: 204

 

CHAMBER: 65cc

 

VALVE SIZE: 2.00 / 1.55

 

PRICE: N/A

 

FLOW@.100: 83 / 55

 

FLOW@.200: 134 / 98

 

FLOW@.300: 189 / 130

 

FLOW@.400: 222 / 156

 

FLOW@.500: 240 / 175

 

FLOW@.600: 252 / 182

 

 

GM Bow Tie

 

PORT SIZE: 175

 

CHAMBER: 55cc

 

VALVE SIZE: 2.05 / 1.6

 

PRICE: N/A

 

FLOW@.100: 61 / 54

 

FLOW@.200: 123 / 103

 

FLOW@.300: 179 / 130

 

FLOW@.400: 214 / 148

 

FLOW@.500: 226 / 157

 

 

So do you have a link that lists what years and models of cars I should look for at the junk yard for these heads. Especialy in aluminum with strait plugs.

 

Thanks again !!