Match Race = 1968 Road Runner '383' vs. 1964 Belvedere '426-S' Street Wedge

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The 906 heads flow better, better cam and intake, better avs carb, better complete exhaust, better hurst shifter on the after February RR, didn't the early 8.75 rears use more power to turn? My 4 gear RR came through with the hemi leafs!
 

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Comparisons

* Cars ..........................1964 Belvedere 426-S 'Sedan' ........... 1968 Road Runner 383 'Coupe'

* Shipping Weight.......... #3465 lbs. ........................................ #3422 lbs.

The Road Runner is {43 lbs.} lighter. But that would make only a minor difference {-.05} in the 1/4 Mile.
--------------------------------------------------------------------------------------------------------------------

* Carburetor ............. AFB .................................................... AVS
* Model .................... #3611 ................................................ #4426
* CFM ........................ 575 .................................................... 625
* Throttle Sizes ........ 1.437" x 1.563" .................................. 1.437" x 1.686"

Advantage with the Road Runner. The Carter AVS {625 CFM} provided 'more' fuel than the Carter AFB {575 CFM}.

And the bigger Secondary {1 11/16"} provided more Top-End.

The Carter AFB {575 CFM} for the 426 Street-Wedge was woefully under-sized.
 
The Carter AFB {575 CFM} for the 426 Street-Wedge was woefully under-sized.
Click to expand...

Understatement of the century.

Smaller carb, smaller exhaust valves, smaller exhaust... let that thing breath.
 
Intake Manifolds

1964 Belvedere '426-S' ................... 1968 Road Runner '383'

Casting ....... #2206000 ...................... #2806301

Type.............. Cast Iron ....................... Cast Iron
Style.............. Dual-Plane .................... Dual-Plane
Design........... Low-Profile ................... Low-to-Medium Profile
Carb Height... 3.30" ............................ 3.44"

The Intake Manifold for the 426-S 'Street Wedge' was considered the 'Dog-of-Dogs'.
 
That 426 wedge car sounds like it would respond great to some simple bolt ons like headers, intake, and carb.
Probably would get 40 to 50 more horses out of that alone.......
Add a bigger cam and now we're really talking!
But in pure stock form, my nod goes to the Road Runner.
 
Engine ----------------- 1964 '426-S' ----------------------- 1968 '383'

* Bore........................... 4.25"...................................... 3.75"
* Stroke........................ 3.75"...................................... 3.38"
* Compression Ratio..... 10.3 - 1 ................................. 10.0 - 1

* Advertised HP............ 365 HP @ 4800 RPM's ........... 335 HP @ 5000 RPM's
* Advertised Torque..... 470 Ft/Lbs. @ 3200 RPM's .... 425 Ft/Lbs. @ 3400 RPM's

* Engine Dyno HP ........ 317 HP @ 4700 RPM's ........... 310 HP @ 5000 RPM's
---------------------------------------------------------------------------------------------------------------

Drag Race Test

Both cars equipped with;
* 4-Speed Transmission
* Hurst Shifter
* 3.91 Gears w/Sure-Grip
* Cheater Slicks {7" Width x 28" Tall}
----------------------------------------------------------------------------------------------------------------

1st Gear

The Road Runner would get off-the-line first, with the advantage of the shorter engine stroke. The 426-S
was notoriously sluggish coming out-of-the-hole.

The Road Runner would jump to a full car-length lead mid-way thru 1st-Gear.

But, by the end of 1st-Gear, the 426-S {Torque Advantage} would start to open up.


2nd Gear

Advantage for the 426-S 'Street Wedge'. Once the RPM's got up in the Engine, the 426-S would start to breath, and
pull on the 383 {shorter stroke}.

By mid-way thru 2nd-Gear, the 426-S would pull 'near even' with the Road Runner 383.

By the end of 2nd Gear, the 426-S would have a 'slight lead'.


3rd Gear

The 426-S would maintain it's 'slight advantage' thru early 3rd-Gear, and start to pull on the Road Runner 383 by
mid-way thru 3rd-Gear.

The 426-S {+43 Cubic Inches} would extend it's lead to more than a full car-length by the end of 3rd-Gear.


4th Gear

A 'surprise' here. What should be expected, is that the Belvedere 426-S {with +43 Cubic Inches} and longer stroke,
should pull away from the Road Runner 383.

But on 'Top End', the 426-S would starve for fuel.
1} The Carter AFB {575 CFM} limited Air-Fuel mixture.
2} The low-profile Intake Manifold would restrict breathing.
3} Also, the 'weak' Valve Springs would float out at 4800 RPM's.

The Road Runner 383 would make a move, and nearly catch the Belvedere 426-S at the 'Traps'.
1} The Carter AVS {625 CFM} would provide more Air-Fuel mixture.
2} The better design Intake Manifold would provide better flow on Top-End.
3} More Cam {Lift and Duration}, with higher load-rate Valve Springs.
4} Better flowing Cylinder Heads.
5} Better Exhaust System.
 
1964 Belvedere 'Sedan' {2-Door}

1964 Production Numbers
* Total .................. 5364
* 426-S ................ {227}

Moniker
"426" Commando
426-S
426 Street Wedge
426 Mild





 
69 Cuda 440 said:
* Plymouth ------------1964 Belvedere {Sedan} ------ 1968 Road Runner {Pillared Coupe}

* Engine ----------------- '426' Commando --------------- Road Runner 383

* Shipping Weight -------- #3347 lbs. --------------------- #3422 lbs.
*Weight-to-Horsepower --- 9.17 --------------------------- 10.22


* Bore................................ 4.25"...................................... 3.75"
* Stroke............................. 3.75"...................................... 3.38"
* Compression Ratio......... 10.3 - 1 ................................. 10.0 - 1

* Advertised HP............... 365 HP @ 4800 RPM's ........... 335 HP @ 5000 RPM's
* Advertised Torque........ 470 Ft/Lbs. @ 3200 RPM's .... 425 Ft/Lbs. @ 3400 RPM's

* Engine Dyno HP ........... 315 HP @ 4700 RPM's ........... 310 HP @ 5000 RPM's
---------------------------------------------------------------------------------------------------------------

Drag Race Test

Both cars equipped with;
* 4-Speed Transmission
* Hurst Shifter
* 3.91 Gears w/Sure-Grip
* Cheater Slicks {7" Width x 28" Tall}
----------------------------------------------------------------------------------------------------------------

1st Gear

Despite being {+75 lbs.} heavier, the Road Runner would get off-the-line first.

The 383 gains the advantage because of the shorter engine stroke, and quicker RPM gain.

The '426 Street Wedge' was notoriously sluggish coming out-of-the-hole.

The Road Runner would jump out to a '3/4' car length lead thru 1st-Gear.

But, by the end of 1st-Gear, the bigger 426 engine {+43 cubic inches} would start to make it's move.


2nd Gear

Advantage for the 426-S 'Street Wedge', as this engine had 'strong' Mid-Range Torque.

Once the RPM's got up in the Engine, the 426-S would start to breath, and catch the 383 {shorter stroke}.

By mid-way thru 2nd-Gear, the 426-S would pull 'even' with the Road Runner 383.

And, by the end of 2nd Gear, the 426-S would have a 'slight lead'.


3rd Gear

The 426-S would add to it's 'advantage' thru early 3rd-Gear, and continue to pull on the Road Runner 383 by
mid-way thru 3rd-Gear.

The 426-S {+43 Cubic Inches} would extend it's lead to a full car-length by the end of 3rd-Gear.


4th Gear

A 'surprise' here. What should be expected, is that the Belvedere 426-S {with +43 Cubic Inches} and longer stroke,
should pull away from the Road Runner 383.

But on 'Top End', the 426-S would starve for fuel, and flatten out.
1} The Carter AFB {575 CFM} limited Air-Fuel mixture.
2} The low-profile Intake Manifold would restrict breathing.
3} Also, the 'weak' Valve Springs would float out at 4800 RPM's.

The Road Runner 383 would make a move, and nearly catch the Belvedere 426-S at the 'Traps'.
1} The Carter AVS {625 CFM} would provide more Air-Fuel mixture.
2} The better design Intake Manifold would provide better flow on Top-End.
3} More Cam {Lift and Duration}, with higher load-rate Valve Springs.
4} Better flowing Cylinder Heads.
5} Better Exhaust System.
Click to expand...

Result

The 1964 Belvedere '426-S' holds off the 1968 Road Runner '383' by a nose.

1964 Belvedere '426-S' ....... 14.26 @ 97.50 MPH
1968 Road Runner '383' ...... 14.28 @ 99.77 MPH
 
Wow, thought the 426 would really be the definate leader, but after seeing all the disadvantages it has,I guess it's lucky to barely beat the RR.
 
This one was interesting. Didn't know that the 426 wedge was a dog off the line. I had the 'Runner taking the win at the top end mostly due to better breathing.
 
2 Darts said:
This one was interesting. Didn't know that the 426 wedge was a dog off the line. I had the 'Runner taking the win at the top end mostly due to better breathing.
Click to expand...

Yes,

The 426-S 'Street-Wedge' was a 'slug' coming off-the-line.

To get more 'oomph',

Back-in-the-Day, we would pull the Intake Manifold off and stuff rags in the Cylinder Head Intake Ports
and gasket-match the ports.

Then we would pop on a 1967 440 HP Intake Manifold with a 1" tall Carburetor spacer.

Then add a Carter AFB {750 CFM} with 1 11/16" x 1 11/16" throttle bores.

What a difference..............
 
1964/1965 > 426-S 'Street Wedge' Intake Manifold

#2206000

* Cast Iron
* Dual-Plane
* Low-Profile
* Primary....... 1.437"
* Secondary... 1.563"



[URL="http://www.440source.com/2206000.jpg"]


Below, the highly desirable 1967 440 HP Intake {#2806178}

2806178.jpg

[/URL]
 
Your Welcome A-Body-Bomber,

The 1964/1965 426-S 'Street Wedge' Intake Manifold is generally regarded as a poor unit.

The Low-Profile Design was adequate for 'low' RPM Horsepower and Mid-Range Torque, but it restricted
flow and limited 'higher' RPM breathing.

By comparison, the 1968 '383' Intake had nearly 50% more flow in the runner ports.
 
69 Cuda 440 said:
'Econo-Racer' Street Musclecar Match Race

1968 Road Runner {383/335 HP}
* Coupe
* 4-Speed
* 3.91 Gears
* Shipping Weight....... #3422 lbs.

1964 Belvedere {426/365 HP}
* Coupe
* 4-Speed
* 3.91 Gears
* Shipping Weight...... #3347 lbs.
Click to expand...

Corrected Shipping Weight
 
69 Cuda 440 said:
First Hand Experience,

The 1964 Belvedere '426' Commando {Shipping Weight; #3347 lbs.}

Though the '426-S' {365 HP} was over-rated in the HP Department by the Factory, on the street it was consistently good.

* 365 HP @ 4800 RPM's
* 470 Ft/Lbs. of Torque @ 3200 RPM's

And, the 'Sedan' body style was 'stiff-and-rigid'.

Just add Gears and Headers, and the 426 Street Wedge was a top runner on the street.



Click to expand...

Street Sleeper.

The only 'moniker' was the 426 Hood Emblem.
 
69 Cuda 440 said:
Comparisons

* Cars ..........................1964 Belvedere 426-S 'Sedan' ........... 1968 Road Runner 383 'Coupe'

* Shipping Weight.......... #3347 lbs. ........................................ #3422 lbs.

The Belvedere 'Sedan' with the '426' Commando is {75 lbs.} lighter.

That would be worth .10 {1/10th} in Elapsed Time.

--------------------------------------------------------------------------------------------------------------------

* Carburetor ............. AFB .................................................... AVS
* Model .................... #3611 ................................................ #4426
* CFM ........................ 575 .................................................... 625
* Throttle Sizes ........ 1.437" x 1.563" .................................. 1.437" x 1.686"

Advantage with the Road Runner. The Carter AVS {625 CFM} provided 'more' fuel than the Carter AFB {575 CFM}.

And the bigger Secondary {1 11/16"} provided more Top-End.

The Carter AFB {575 CFM} for the 426 Street-Wedge was woefully under-sized.
Click to expand...

Leaning with the Belvedere over the Road Runner.
 
In 1964,

Plymouth Production Numbers

Savoy 'Sedan'
* Total .......................... 21,326
* '426' Commando ........ {760}

Belvedere 'Sedan'
* Total ........................... 5364
* '426' Commando' ....... {227}

Belvedere 'Hardtop'
* Total ......................... 16,334
* '426' Commando ........ {852}

Fury 'Hardtop'
* Total.......................... 26,303
* '426' Commando ....... {1273}

Fury 'Convertible'
* Total .......................... 5173
* '426' Commando ....... {205}

Sport Fury
* Total ......................... 23,950
* '426' Commando ....... {1814}

Sport Fury 'Convertible'
* Total .......................... 3858
* '426' Commando' .......{184}
 
Chino,

The 426 Street Wedge was really a long stroke 383.

The only difference in Engine Components besides {+43 Cubic Inches}, was that the
426 Street Wedge had different Exhaust Manifolds, with a rear outlet exit angled at 45*.

Both had 2.25" Manifold Header outlets, and 2.25" Primary Piping, with 2.25" Tail Pipes.

The 1964/1965 > 426 'Street Wedge' and 383 4-Barrel both had the same
* Carter AFB {575 CFM} Carburetor
* Cylinder Heads {#2406516}
* Valve Size {Intake 2.08" / Exhaust 1.60"}
* Camshaft {Hydraulic}
* Valve Springs
* Dual-Point Distributor

* Compression 426/365 HP = {10.3-1}
* Compression 383/330 HP = {10.0-1}
 
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