Concerned With Port Mismatch

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
Hi.

I need a intake manifold that fits the ports on my double hump 3782461 heads.

The intake ports are 50.30mm x 28.77mm something like 1.98" x 1.13".

Is there a intake manifold that match the ports?

If not I have read it’s important that the intake manifold has smaller ports then the heads, something about turbulence with sharp corners and edges.

The engine (327 with full roller) has dyno results 360hp @ 5700rpm with Edelbrock C3B intake with intake ports 49.45mm x 32.0mm (not a good match)

I have three intake manifolds on the shelf:
Edelbrock C3B intake with intake ports 49.45mm x 32.0mm (1.95" x 1.26")
Holley 300-38 Street Dominator with intake ports 43.2mm x 27.0mm (1.69" x 1.08")
Edelbrock performer 2101 47.75mm x 28.96mm (1.88" x 1.14")

I don’t have the time or tools to port the heads, but I can port a intake manifold.

Any suggestions on intake manifold, or a manifold that I can port to match the heads?
Or is it overrated to match the manifold to the heads with only 360hp?



minor mis-matches in the port shape, in height or width are NOT critical,
and I certainly would not be very concerned with minor mis-matches,
now if you can match the ports it certainly won't hurt, to do so,
but its really not critical if the ports have minor mis-matches
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

http://garage.grumpysperformance.co...-by-step-guide-with-pictures.5378/#post-71848

http://garage.grumpysperformance.com/index.php?threads/porting-can-help.462/page-3#post-91237
 
Last edited:
Back
Top