Conclusion
This swap to the Indy SR heads delivered a knockout punch beyond our expectations. Imagine the difference if we had tested them against a stock set of heads, either 906 or 452 castings. Moving to a more aggressive cam and a bigger carb would have surely given us a mid-10-second, pump-gas street car. Of course, for now, that's merely speculation. If you decide to use Indy heads on your B/RB, be sure to plan your combination wisely and don't try to put these heads on a low-compression motor and expect big gains.

Indy SR Heads Flow Chart
As tested at Ray Barton Racing Eengines SF-600 Flow Bench

Intake Flow

Lift
Intake
StockStock With
Back-Cut
PortedPorted With
Back-Cut
Port & Polish
W/Back-Cut
Port & Polish
With Back Cut and
MaxWedge style
.200139147142148148150
.300198205195198203215
.400245251239242250266
.500270278278280282308
.600280290301302305335
.700288291317319320357
.800290297331331333374

Exhaust Flow

LiftStockPortedPorted & Polished
.200112112112
.300149150151
.400192192195
.500214213215
.600232235239
.700245247252
.800253257260

Note: Indy sells the SRs with optional CNC super-modified porting with the Max Wedge-size intakes. It will save you many hours while returning flow numbers and performance equal to, or better than we achieved.

Chassis Dyno Results
Superflow SF840 SAE-corrected rear-wheel horsepower and torque tested at SLP Performance Parts & Engineering Center

Baseline W/906Indy w/40 TimingX StreamWilson Space
Max hp @ rpm366 at 5,600433 at 5,600433 at 5,600433 at 5,600
Max tq @ rpm427 at 4,200457 at 4,200460 at 4,200465 at 5,600
Avg hp @ 4,000-6,000350394397403
Avg tq @ 4,000-6,000367410414421
SOURCE
Schumacker Creative Services
2-06/-364-7151
engine-swaps.com
Wilson Manifolds
4700 NE 11th Ave.
Ft. Lauderdale
FL  33334
954-771-6216
www.wilsonmanifolds.com
Indy Cylinder Head Inc.
3-17/-862-3724
indyheads.com
Ray Barton Racing Engines
Robesonia
PA
6-10/-693-5700
raybarton.com
K&N Engineering Inc.
N/A
KNfilters.com
Tube Technologies Inc. (TTI)
Corona
CA
9-51/-371-4878
ttiexhaust.com
Randy's Ring and Pinion
8-00/-347-1188
ring-pinion.com
Red Line Synthetic Oil Corporation
7-07/-745-6100
redlineoil.com
SLP Performance Parts
1501 Industrial Way North
Toms River
NJ  08755
831/44 Center W/391s & Clutch-Type