as I expected, I had someone ask me why I could possibly even suggest use of a 225cc port head on a TINY 383 SBC BUILD?
well as we gain experience you either use that experience to LEARN and improve or you ignore it and just keep making similar mistakes to those you've done in the past!
from what Ive seen you get significant gains in the mid and upper rpm ranges with those brodix heads over the typical 200cc and 210cc heads most guys use, on a serious street/strip combo sbc build with MINIMAL lower rpm power /torque losses , now I have to point out that if your cruising along at a steady 70mph, your using maybe 45-60hp to keep the car cruising at that steady speed, so youll never notice the potential loss of torque nor the minute or marginal loss of air flow port speeds, and once you stomp your gas petal to the flow your pushed back in the seat nearly instantly, and won't notice any loss in the power band for the first 1/2 second or so before the engine reaches its peak power, where theres actually some power gained.
lets look at the differences in port size/volume a second.
I see several guys suggest this afr head notice its about $120 more
at $1950 a pair
it has a 2.110" H x 1.265 port opening (thats 2.669 sq inches) 10% smaller cross sectional area than the brodix heads below
195cc Street Head Flow Chart | | | | | |
| .200 | .300 | .400 | .500 | .550 |
Int | 146 | 201 | 247 | 275 | 280 |
Exh | 119 | 166 | 197 | 213 | 218 |
Cylinder Head Specialists
www.airflowresearch.com
I suggested this head(matched to the long runner TPI FIRST INTAKE who's long individual,
runner design more than compensates in maintaining air flow inertial mass and speeds in the mid and upper rpm ranges
Economical out-of-the-box horsepower is what comes to mind with this new series of Dragon Slayer series small block aluminum cylinder heads from BRODIX. SBC
brodix.com
Match Intake Port to
FP 1206 (NOT A HUGE PORT SIZE) $1830
yet they come with larger 2.08 intake valves and stronger 7/16" rocker studs
Free Shipping - Brodix Cylinder Heads Dragon Slayer 23 Degree Cylinder Heads with qualifying orders of $109. Shop Cylinder Heads at Summit Racing.
www.summitracing.com
Flow Chart cfm @ 28" H20
�
Part Number | Valve Size | 0.200 | 0.300 | 0.400 | 0.500 | 0.600 | 0.650 | 0.700 |
---|
DS 225 | 2.080 Intake | 142 | 212 | 260 | 287 | 302 | 302 | 304 |
1.600 Exhaust | 115 | 154 | 183 | 199 | 204 | 207 | 210 | |
find the closest intake gasket and use it as a guide to match the ports to as close as possible
COMMON SBC INTAKE GASKET PORTS
felpro # 1204=Port Size: 1.23" x 1.99"=2.448 sq inches
felpro # 1205=Port Size: 1.28" x 2.09"=2.67 sq inches
felpro # 1206=Port Size: 1.34" x 2.21"=2.96 sq inches
felpro # 1207=Port Size: 1.38" x 2.28"=3.146 sq inches
felpro # 1209=Port Size: 1.38" x 2.38"=3.28 sq inches
felpro # 1255 VORTEC=Port Size: 1.08" x 2.16"-2.33 sq inches
felpro # 1263=Port Size: 1.31" x 2.02"=2.65 sq inches
felpro # 1266=Port Size: 1.34" x 2.21"=2.96 sq inches
felpro # 1284 LT1=Port Size: 1.25 x 2.04''=2.55 sq inches
felpro # 1289 FASTBURN=Port Size: 1.30" x 2.31" 3.00 sq inches