tomas_wallin

I have been trying to use desktop dyno but cant get it right...

The setup as follows:
Stock bottom 454 Gen V 330hp (1995)
Heads: GM Vortec 105cc CC, Large oval 230cc int ports, D shaped exh ports
Valves: 2.19int/1.88exh
Intake: Holley 300-42
Carb: Edelbrock 1410 750cfm
Cam: Comp Cams Extreme Marine CL11-236-4
Dur @ 0.50: 226int/236exh
Lift: 0.544int/0.547exh
Lobe: 112
Exhaust: Manifolds from GIL
Dry exhaust through transom, no mufflers
Complete MSD ignition
Rpm limit set at 5100rpm
K&N Air filter


That should be it.

Thanks!

Crazyhorse

I haven't got DT on my computer here at work but part of your problem may be that the compression ratio is going to be higher than stock due to the 105cc chambers on the vortec heads. A wild guess on c/r would be 8.5:1.

Griff

+/- 425 HP or so would be my guess also.

tomas_wallin

Thanks for the answers!

Do you know of anyway to get the flow numbers for the vortec heads? I assume GM has some numbers but that seems to be a long shot...

KAAMA

iTrader: (1)

tomas, call "JimV" at 616-735-0800. He has ported, and flowed many head designs, and may have some flow numbers on the Vortechs that you are looking for.

rmbuilder

Tomas,
Here are the flow #'s for the L-29 Vortec heads @ 28" H2O:
.100".....63.....49.....77%
.200".....121.....91.....75%
.300".....165.....120.....73%
.400".....198.....133.....67%
.500".....226.....140.....62%
.600".....242.....142.....59%
There is a significant drop off in the mid/higher lift flow numbers that you need to address in cam selection.
Bob

tomas_wallin

Thanks!!!

Are these numbers for stock valves? I put Manley 2.19/1.88 in mine.

How do I translate the numbers...
lift.....int.....exh.....exh/int?

tomas_wallin

I assume I need some numbers for the GIL exhaust too? Or how do I do with the exhaust input?