'1970' Road Runner '383' vs. AMC Rebel Machine '390'

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69 Cuda 440

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1970 Match Race,

1970 Plymouth Road Runner 383 {335 HP}
vs.
1970 AMC Rebel Machine 390 {340 HP}

The 'new' stylish 1970 Road Runner, a little bulkier than the
stripped down 1968 and 1969 Road Runner, but still only
at #3475 lbs. 'Shipping Weight' Hardtop.

But, now with an optional 'Air-Grabber' Hood Scoop.

The 383 Engine had the same components as the 1968 and 1969 Engine,
but in California a 'special' Holley #4160 {680 CFM} Carburetor was required
to meet 'emission standards'.

In all other states, the 383 received the 'standard' Carter AVS {625 CFM}.

For Gears, the {3.23} was standard, but in 1970 'optional gears' {3.55 ~ 3.91}
were now available.

In 1970, was classed in NHRA G/S or G/SA.

A 'stock' 383/335 HP Road Runner with a 4-Speed and 3.23 Gears w/Sure-Grip was
capable of 14.90's @ 96 MPH.

 
1970 American Motors Rebel 'Machine'

A 'special' performance version of the 390 with 340 Horsepower,
featuring a 'special' Camshaft, new 'Dog-Leg Port' Cylinder Heads and
and 'special' Exhaust Manifolds with large outlets.

th
 
sales were down for the 70 RR, almost half of what it was in 69. ill take the Machine if gear ratio is about equal
 
The 1970 Road Runner 383,

335 HP ~ #3475 lbs. = {10.37 Wt/Hp}

Could be purchased with gears up to 3.91 though very few were ever ordered
that way.

Most came with the standard {3.23 Sure-Grip}, and/or with 3.55 cogs.

Code #A31 {3.91 Gears} was the 'High-Performance Axle Package'.

If the 1970 Road Runner was 'optioned' with 3.91 Gears and the 'Air Grabber'
air induction unit, a 4-Speed {with performance tune-up} was capable of
14.30's @ 98 MPH.

The 'California Emission' Holley Carburetor cars {Holley #4367} with
{1 9/16" Primary ~ 1 3/4" Secondary} with a 680 CFM Rating actually
were better performers on the track, if you 'yanked' all the C.A.P. pollution
control vacuum lines off the Carb and Intake.

Holley #4367 (Manual} ~ Holley #4218 {Automatic}

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That was probably my all time favorite RR ad up there!
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Optioned with;
* 15" x 7" Rallye Road Wheels
* F-60 x 15" Goodyear Polyglass GT Tires
* Performance Hood Treatment
* Body Side Stripe

My neighbor {female} had one just like below photo.

A Coupe with 'automatic'.

They were sharp-looking cars.

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I'm also leaning towards the AMC here. All their engines are small blocks and pretty potent, so I'm thinking there's an advantage here for the Rebel Machine.
 
1970 AMC Rebel 'Machine'

390/340 HP
#3650 lbs.
{10.73 Wt/Hp}

1970 NHRA Class = H/S or H/SA

Low Production Numbers........ 2326 Built

* 3.54 Gears w/Twin-Grip Differential....{Optional 3.91 Gears}
* Ram-Air Hood 'Air Induction'
* Special Exhaust Manifolds..................{2.5" Outlets}
* Special Camshaft..............................{.457" Lift ~ 296* Duration}
* E-60 x 15" Tires................................{15" x 7" Road Wheels}
* Hurst Shifter and Linkage
* Borg-Warner T-10 Transmission
* Autolite Carburetor {670 CFM}
* Special High-Rise Cast Iron Dual-Plane Intake Manifold

Advertised as a 14.40 @ 99 MPH 'Machine'.

That is debatable,,,,,,,,,,

As I saw a 'Brand New' Rebel Machine at the Track {Dover Drag Strip} in 1970,
that Geis Motors Rambler/AMC was 'showcasing' on a Dealer-Day 'Sunday', and it
lumbered to 15.10's @ 92 MPH, but that may have been with no 'trick tuning', or
possibly a bad driver.
 
Tell ya whut. I've seen that "under 3500 lbs" figures before for 70 B bodies and I have one word that starts with "B"

Mine, originally a 440-6, but with headers, side exit tail pipes, and aluminum intake and 800 Holley STILL weighed a lot closer to 3800 than it did 34--somethin. Mine admittedly had the track pak and Dana 60 so a little more weight there.

SOMEPLACE, after all these years, I still have a weight slip for that thing.
 
Based on 'Shipping Weight' numbers from the 'factory' and NHRA factoring
specifications.

Curb Weight can easily add anywhere between #150 lbs. and #250 lbs.

'Your numbers may vary'............depending on 'barometric pressure'.
 
Kalvinator played the same hp game. The "machine" was a traction limited 14.0 flat any day runner. I didn't like 'em but there were a few around.
 


A 'stock' 1970 Rebel Machine

Even with 3.91 Gears 'Twin-Grip' Differential, 'The Machine' wasn't running 14.00's @ 100 MPH.

They got 'hammered' in H/S or H/SA in 1970 and 1971 at NHRA Tracks,
and in Super/Stock {SS/J or SS/JA} in 1972 and later,,,,,,,,,

They were nice and smartly detailed 'Street Performance Cars', that were targeted
for a 'limited customer base'.

They were 'not' feared on the Street.
 
I don't remember if it was AMC advertisements for this car or another AMC performance car.
I would have fired the copy writer.
It went something like "it isn't as fast as a HEMI Cuda, but it is pretty quick"
This was in an AMC ad copy that I read once. Not the best way to try & sell a performance car, by apologizing for it.
 
Mike,

If you remember the way AMC was managed, the guy who did the 'Ad'
probably got a raise and a promotion to Executive Director of Sales and Marketing.
 
'3' Mopar Guys from Nebraska checking out the Rebel 'Machine'.

"You know something Bubba, this 'Machine' would make a nice Tow Car for our 63' Max-Wedge."

1970RebelMachine.jpeg
 
The classic Magazine Ad,

'For instance, it is not as fast as on the getaway as a 427 Corvette, or a Hemi,
but it is faster on the getaway than a Volkswagen, a slow freight train, and
your old man's Cadillac.'

'Classic wording by the Ad Agency'

1.jpg
 
I for one like the Machine.
But that ad didn't give you a real good reason to buy that product.
If I'm selling water, I'm going to tell you my water is the wettest that you can buy. LOL
 
I do remember back in 1970, a Service Manager for our local
American Motors/Rambler/Buick Dealership {Geis Motors} had a Rebel 'Machine'.

The car did sit real nice, kind of high as it had 'special' suspension and
15" E-60 x 15" tires.

And, the exhaust was loud. The 'Machine' did sound real good.

70rebelmachine-2.jpg
 
69 Cuda 440 said:
The classic Magazine Ad,

'For instance, it is not as fast as on the getaway as a 427 Corvette, or a Hemi,
but it is faster on the getaway than a Volkswagen, a slow freight train, and
your old man's Cadillac.'

'Classic wording by the Ad Agency'
Click to expand...

I wonder if the guy who wrote that ever told his wife "hey, not bad....I've seen worse" when she bought a new outfit. LOL
 
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