71-73 Swag

  • New T-Shirt Design (Also coffee mugs and posters!) – read more!
  • Mach 1 Key Tags available (almost gone!) – read more
  • Convertible Key Tags available (limited supply) – read more
  • Coupe Key Tags available (only a few left) – read more

  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
351 4v Intake question, can this be right?
#1
OK, putting my closed chambered 4V heads on my 71 M code Mach tomorrow. I repainted them the proper dark Ford blue after it was pointed out that's the correct color. After comparing the weights of the standard 4V intake with an Edelbrock Performer 4V intake, I decided to go with the Edelbrock. I noticed that the ports of the Edlebrock 4V Performer are smaller than the ports of the heads, the original cast iron intake has the same size as the heads. Shouldn't the Edelbrock 4V ports be the same size or is it not an issue?


.jpg   Intake.jpg (Size: 46.71 KB / Downloads: 180)
.jpg   Intake2.jpg (Size: 96.3 KB / Downloads: 179)

Jim

M code 71 Mach 1, 351 4V Cleveland, Ram Air (not factory), C6 Trans, 3.5 rear
  Reply
#2
The ports on the Performer are intentionally smaller to provide better flow velocity. It will not be a problem. If the port were smaller than the manifold it would create turbulence at the port inlet which would be a problem. You could port match the manifold but would not likely gain much performance.

Some performance/race manifolds like the Edelbrock Victor are quite a bit smaller to provide more meat for port matching.

Jeff T.

Low buck, touring style, '73 Convertible "rolling restoration", 351c, 2v heads with a shave and a haircut, Performer intake, Holley 650(ish), roller rockers, screw in studs, guideplates, stainless valves, Duraspark / Motorsports MSD, T-5 conversion. 1-1/8" front, 3/4" rear swaybars KYB shocks and some home brewed subframe connectors. Future plans; JGC steering box, Cobra brakes and... paint, interior, etc.

When I die I want to die like grandpa, peacefully in my sleep... not screaming, like his passenger.

[Image: 1_12_09_14_10_15_11.png]
  Reply
#3
On my old motor I used a gasket set to port match both my heads and intake. Put some blue machinist die on the head and traced the gasket same with the intake then took die grinder to them and matched them up. Not sure how much I gained but figured it couldn't hurt.

Kevin

1971 Mach 1
408C Stroker
C4 w/3,000 stall
8.8" Rear w/3.73's
Disc brakes all way around.

[Image: 28ivsix.png]




                                                                                             
  Reply
#4
droptop73;170988 Wrote:The ports on the Performer are intentionally smaller to provide better flow velocity. It will not be a problem. ...

Thanks Jeff, that's a load off my mind!

Those puppies are going on tomorrow and off with the 2V heads that the prior owner had put on it.

   
.jpg   Intake3.jpg (Size: 135.22 KB / Downloads: 160)

Jim

M code 71 Mach 1, 351 4V Cleveland, Ram Air (not factory), C6 Trans, 3.5 rear
  Reply
#5
+1 the smaller ports keep them from loading up as easily.

COOL PROJECT!
  Reply
#6
Just a rhetorical question, but why would you want
to use a smaller/mismatched intake on a Cleveland?

mike

[Image: 1_11_11_13_11_50_27.png]
  Reply
#7
to compensate for the oversized ports at lower RPM's (in theory I suppose)

[Image: 1_01_07_15_8_53_18.png]

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!
  Reply
#8
Exactly, throttle response comes from flow velocity not flow volume. When an air column is moving faster it fills the cylinder better.

Jeff T.

Low buck, touring style, '73 Convertible "rolling restoration", 351c, 2v heads with a shave and a haircut, Performer intake, Holley 650(ish), roller rockers, screw in studs, guideplates, stainless valves, Duraspark / Motorsports MSD, T-5 conversion. 1-1/8" front, 3/4" rear swaybars KYB shocks and some home brewed subframe connectors. Future plans; JGC steering box, Cobra brakes and... paint, interior, etc.

When I die I want to die like grandpa, peacefully in my sleep... not screaming, like his passenger.

[Image: 1_12_09_14_10_15_11.png]
  Reply
#9
I didn't notice any valve stem seals?

[Image: Image3.png]
Jim
  Reply
#10
They're there... the blue things inside the springs.

Jeff T.

Low buck, touring style, '73 Convertible "rolling restoration", 351c, 2v heads with a shave and a haircut, Performer intake, Holley 650(ish), roller rockers, screw in studs, guideplates, stainless valves, Duraspark / Motorsports MSD, T-5 conversion. 1-1/8" front, 3/4" rear swaybars KYB shocks and some home brewed subframe connectors. Future plans; JGC steering box, Cobra brakes and... paint, interior, etc.

When I die I want to die like grandpa, peacefully in my sleep... not screaming, like his passenger.

[Image: 1_12_09_14_10_15_11.png]
  Reply
Share Thread:  


Possibly Related Threads...
Thread Author Replies Views Last Post
  351C Stroker / TKO 600 bellhousing question tony-muscle 11 724 03-29-2018, 03:18 PM
Last Post: tony-muscle
  FMX Transmission casting number question? Monterey 6 204 03-01-2018, 11:45 AM
Last Post: Vicus
  internals on 71 351 m old henry ford 17 622 02-10-2018, 05:58 PM
Last Post: Boss1Ray
  351 Cleveland 2V Coolant System Noise Bluesky10 10 564 02-04-2018, 06:49 PM
Last Post: Bluesky10
  What should be done to a 351 CJ head? scgamecock 10 666 01-23-2018, 08:29 AM
Last Post: Ron Tanzi
  Suggestions for carb/intake combination mild rebuild timachone 15 610 01-20-2018, 02:15 PM
Last Post: Canted 393
  351 Boss or Cleveland 8.8 mm plug wire looms kcmash 2 450 01-15-2018, 09:00 AM
Last Post: Pegleg
  351 c distributor bushing boilermaster 14 648 01-13-2018, 09:28 AM
Last Post: Stanglover



Users browsing this thread: 1 Guest(s)