502 BBC

[grumpyvette]

I found this rather interesting dyno result posted else ware,
stock zz502 bottom end, qualified, zero decked and clearanced for higher rpm's
104cc max angled milled AFR 315's net 10.2 compression
Custom UDHarold Solid Roller 255/263 duration at .050 lift 725/707 lift 110/106 lsa
as cast HV2000
850 Holley/Proform
T&D Shaft Rockers
Melling Select 10778 bench set @ 80psi
open headers / 2" x 3.5"
MSD HEI conversion locked @ 36
Pump gas
Car has TH400 & 28" slicks, rpm's are approximate;

-3:73's, tight 3500 stall, best of 132mph / 6400rpm's(across stripe)

-4:30's, tight 3500 stall, best of 130mph / 7300rpm's

-4:30's, loose 5000 stall, best of 126mph / 6600ish rpm's

-4:30's, loose 5000 stall, Prosystems 1000 (from an 850dp) best of 125mph / 6500ish rpm's

,I knew the gear/tire was a little much for a 6500rpm spec'd cam but, with out a dyno sheet, I wanted to see where the motor actually was making power. The car didn't pick-up any with that gear and it really slowed down with more converter & carb, about 7mph. The motor obviously pulled good down low but was falling off too quick over 6000ish rpm's. I thought with the size of the heads and it being a S/R it would rev higher, at least to 7000, but it didn't like it. I couldn't find much info on this HV2000 Brodix intake. It has extended dividers and consequently smaller plenum area compared to a Vic Jr. Also, the port match area was about 1/4" smaller than the 315 heads. I assume it would be better suited to a smaller BBC without being ported- dunno. In its defense though, it's a quality casting compared to the Vic, has a smooth plenum entry, nice radius at the plenum to port roof and has a built in carb spacer.

 

[87vette81big]

Bigger tube headers may help Grumpy.
Kinda small for a 700+Hp BBC.
They love Big Primary Tubes. 2-1/8 or 2-1/4".
4 " INCH COLLECTOR OR 5" inch.
Use no mufflers. Turn down dumps only.
Be horendous loud but HP be there.

Its a Heavy Street car.
3,800-4200lbs weight .
Mid 10 second ride now.
Few changes made & into the 9's.

BR