Help with my 71' roadrunner

[patmckinneyracing]

How's it going folks. I am new to the website and learning about mopars basically. I'm 18 and finished turning my 80' malibu in a street-strip car and really wanted a mopar (blame dad for that lol, 67 Dart GTS):grin:. Well I scored big and found the mopar I've always wanted that was taken off the road in 77'. This RM23 roadrunner is origionally a california car and is basically rust free and I talked the guy down from 10k to 7.5k. Has numbers matching 383 4 speed and the car is origional to the point of having the factory exhaust. What I'm trying to figure out is the differences and specs between a regular 383 and the "N" code HP 383. Mine just so happens to be the "N" code. Another question I have is how often did 71' roadrunners that had the 383 4 speed come with AC? This car has the AC as well. Finally, this car has what I believed is called a DictAphone (cassette recorder) and had the black bikini vinyl top, origional color curious yellow. Are these options rare on roadrunners?
There's just a lot of things on this car that shows that it was special ordered and not part of a bulk order made by the dealerships. Case and point, its a 4 speed with the bucket seats, console, etc. but has AC and has a Clock instead of the RPM Gauge. I'm not sure how rare the bikini vinyl top is either. But with the options this thing has, along with the dictAphone, I believe the origional owner was a doctor or something along those lines. He wanted to look badass in this thing with all the racing options but at the same time have the lucturies such as the AC, vinyl top, etc. As we all know, these things ordered in bulk were nothing but bare bone cars, and if any muscle car guy from back then ordered one of these, he wouldn't want the AC or other luxuries.
Unfortunately, this car did have the build sheet but a rat or mouse made a home underneath the back seat and made some nesting out of it. I saved whatever scraps were legible. Here's the fender tag codes:

first 7 vin # RM23N1G

V8X 26 END
M21 N41 N97 R36 V21
C55 G11 G36 H51 J45 L31
V4X U A01 A87 B11 C16
GY3 M6X9 TX9 610 040964
E65 D21 RM23 N1G

 

[69 Runner]

Welcome. You've got a pretty cool car there, one worth a proper restoration (as opposed to hacking in to a race car). First, it's a 4 speed. Big plus. It's also a 'high impact" color. Also a plus. Then there is the A/C and the cassette. While you don't see tons of 4 speed cars with A/C, it isn't unheard of. The cassette on the other hand is a pretty rare option, and you're lucky it's still there.

As far as differences in 383s goes, a "lo-pro" would have had different exhaust manifolds, cam, valve springs, carb tuning and distributor advance curve. Do NOT let anyone try to snow you with that "magnum head" BS. A 383 2V had the exact same head casting as any of the 4V or Six Pack motors did.

Your fender tag reads from bottom left to top right (if you didn't know that already)


V8X transverse tape stripe, black
26 26" radiator
END end of the tag
M21 chrome drip rail moldings
N41 dual exhaust
N97 noise reduction package (probably a California car, no tips just turn downs)
R36 AM/FM Stereo w/cassette
V21 hood performance treatment
C55 bucket seats
G11 tinted glass
G36 dual painted racing mirrors
H51 A/C
J45 hood pins
L31 hood/fender mounted turn signals
V4X black vinyl roof
U sold car
A01 light package
A87 road runner decor group
B11 hd 11" drum brakes
C16 console
GY3 citron yella
M6X9 medium class bucket seat black
TX9 black interior paint
610 build date June 10, 1971
040964 order number
E65 engine code (383)
D21 trans code (4 speed)
RM23 N1G breaks down to road runner hard top 383 1971 St.Louis ***. plant

 

[696pack]

Welcome. You've got a pretty cool car there, one worth a proper restoration (as opposed to hacking in to a race car). First, it's a 4 speed. Big plus. It's also a 'high impact" color. Also a plus. Then there is the A/C and the cassette. While you don't see tons of 4 speed cars with A/C, it isn't unheard of. The cassette on the other hand is a pretty rare option, and you're lucky it's still there.

As far as differences in 383s goes, a "lo-pro" would have had different exhaust manifolds, cam, valve springs, carb tuning and distributor advance curve. Do NOT let anyone try to snow you with that "magnum head" BS. A 383 2V had the exact same head casting as any of the 4V or Six Pack motors did.
Your fender tag reads from bottom left to top right (if you didn't know that already)


V8X transverse tape stripe, black
26 26" radiator
END end of the tag
M21 chrome drip rail moldings
N41 dual exhaust
N97 noise reduction package (probably a California car, no tips just turn downs)
R36 AM/FM Stereo w/cassette
V21 hood performance treatment
C55 bucket seats
G11 tinted glass
G36 dual painted racing mirrors
H51 A/C
J45 hood pins
L31 hood/fender mounted turn signals
V4X black vinyl roof
U sold car
A01 light package
A87 road runner decor group
B11 hd 11" drum brakes
C16 console
GY3 citron yella
M6X9 medium class bucket seat black
TX9 black interior paint
610 build date June 10, 1971
040964 order number
E65 engine code (383)
D21 trans code (4 speed)
RM23 N1G breaks down to road runner hard top 383 1971 St.Louis ***. plant

Yeah, that was a little "creative license" the marketing department took when advertising the 383 RR and Bee engines as having the "440 Magnum heads." Not untrue as they were used on the 440 Magnums and Super Commandos, as Tem stated above, but they were also used on 383 2 barrels as well.

 

[patmckinneyracing]

Do you know how rare the cassette is? I had another guy on a different forum telling me he heard that only 137 were put into RR's that year. Not sure if this is true or not but would like some verification. I know they sell for 1500 on eBay easily.
But I refuse to turn this car into a racer and will be going with a full factory restoration. May bump up the cam if the previous owner didn't already do that. He claimed he put one of the biggest mopar purple cams into it.
As far as the heads go, this one was the HP 4 barrel 383, so it should have the same heads as a 440 right? I also heard that the 440 and 383 HP shared similar cams and valve springs.

 

[696pack]

That looks like a pretty much untouched/unmolested car. I would think twice before I did a "restoration" on the car, especially if the paint is original. If it is I would hand polish it and them put a wax or poly sealer on it and leave it original as that speaks volume for the car and MANY people are very turned on by it.
I would shampoo the carpets, possibly re-die it and patch what appears to be the hole on the side of the trans hump next to the gas pedal.

 

[69 Runner]

Do you know how rare the cassette is? I had another guy on a different forum telling me he heard that only 137 were put into RR's that year. Not sure if this is true or not but would like some verification. I know they sell for 1500 on eBay easily.
But I refuse to turn this car into a racer and will be going with a full factory restoration. May bump up the cam if the previous owner didn't already do that. He claimed he put one of the biggest mopar purple cams into it.
As far as the heads go, this one was the HP 4 barrel 383, so it should have the same heads as a 440 right? I also heard that the 440 and 383 HP shared similar cams and valve springs.

You must LISTEN young Padawan if you wish to learn:grin:

A 383 2 barrel and a 440 Six Pack have the EXACT SAME HEAD. A 383 4V and a 440 4V (the "magnum" motors) used the exact same cam and valve springs. And before you ask, they had the exact same valves, as did a 383 2V etc etc etc.

I doubt anyone including Galen knows exactly how many were built with the cassette, but it's safe to say it wasn't many.

I also agree with Darryl IF that is the original paint, and IF there are a ton of usable pieces (rear seat, passenger's seat etc) then I wouldn't replace them for the sake of replacing them. The original stuff is better for you in the long run.

As far as the cam goes, something tells me this guy was blowing smoke. I'm betting it doesn't have "one of the biggest purple cams" available.

Assuming you want to run your cast exhaust I can set you up with a cam that will make it go like stink, idle easy, and be a pleasure to drive. It's the same cam I ran in my Certified Stock Six Pack Challenger and I was running 12.80s @110.6 with no traction, but was deceptively sedate and easy to street drive.

 

[69 Runner]

Something else about the heads. Your car being a 71 will probably have either 346 or 452 castings (as opposed to 906s) They are good heads. No need to change. YES, the port configuration is slightly different than a 906, BUT there is a give and take here.

Yes, the 346/452 heads have a slightly flatter intake port than a 906. BUT, they have MORE short side radius on the exhaust side than does a 906. So you loose a little on the intake side, but GAIN a little on the exhaust. A fair trade in my book.

Also, the 452 has induction hardened exhaust seats in them (346s are the same head except for this. NO hard seats). But since this is a simple induction hardening and NOT a hard seat installed in the head, you will loose the hardness when you do a valve job. Best thing at that point is to have hard seats installed (and I also go with bronze guides) and you're set for crappy gas.

 

[696pack]

You are young enough that you may not understand the value of the heads Tem is explaining above. The older heads that didn't have the hardend seats need to have them added to run unleaded gas, so it is money you don't have to spend.

 

[patmckinneyracing]

The problem with leaving the car alone is that the yellow you see isn't the origional color. Some jack*** used yellow spray paint. The next problem is the origional owner screwed up both quarters. The driver side quarter I believe is workable, but the passenger side not so god. There was at least 2 inches thick of bondo on the passenger side, which tells me this guy was t-boned. The frame is good and if i remember right they replaced the door with a 71 charger door.
The interior is going to need to be re-worked. The headliner was sagging and I already took that out and the seats need to be re-upolstered. Now with the motor, the guy was claiming that it had a 525 lift. I doubt this is true but we'll see when I fire it up.
Now concerning the heads and motors etc. , I'm still learning a bit but as far as restorations go, this isn't my first rodeo. Just got finished with my 80' malibu and finishing dad's 67' Dodge Dart GTS. Here's some pics:

http://http://i113.photobucket.com/albums/n211/DarkSnipe5/DartinOct08001.jpg
http://http://i113.photobucket.com/albums/n211/DarkSnipe5/Dartmovie017.jpg
http://http://i113.photobucket.com/albums/n211/DarkSnipe5/Nov08047.jpg
http://http://i113.photobucket.com/albums/n211/DarkSnipe5/Nov08042.jpg

 

[69 Runner]

Isn't your first rodeo, but don't know if a 383 and a 440 use the same head.

Links weren't workin for me

 

[patmckinneyracing]

Sorry bout the links man. Like I said I'm still learning the mopars I learned off dad's dart's 440. Plus my first resto was a chevy which didn't help matters much but was still a good learning experience. Sounds like i'm gonna end up pullin the valve cover to check the numbers.

 

[69 Runner]

If you're planning on driving the car a bunch, I'd consider doing a rebuild on the motor so it can live on bad gas anyway. You will find out then which heads it has and can go from there

 

[alleyoopmgv]

Sweet car! like runner said, one worth a proper restoration, that is a great car (wish I had it!) Keep us updated on progress!

 

[patmckinneyracing]

Of course. I'm gonna restore this thing to factory specs. The only thing I'm considering about doing is converting those big a** drums in the front to A body disc spindle for safety purposes. I've heard plenty of scary stories about drums.

 

[696pack]

Of course. I'm gonna restore this thing to factory specs. The only thing I'm considering about doing is converting those big a** drums in the front to A body disc spindle for safety purposes. I've heard plenty of scary stories about drums.

The Mopar 11" drum brakes will stop that B body just fine, but you don't want to do 2 or 3 panic stops in a row or you WILL get a lot of brake fade on the second stop and will only have about 25% on the 3rd.

You just need to make sure they are in good working order, adjusted right, and assembled right. Many people mistakenly reverse the brake shoe position which effects there braking ability.

 

[69 Runner]

What Darryl said. The 11" drums on my Challenger would stop it just fine from 110+ at the end of a quarter mile. That said, they wouldn't be my choice if I wanted to go to Watkins Glen

 

[patmckinneyracing]

I might just keep the origional drums on the front. Just depends on if I like them or not when I take it for a ride. I would just feel better with discs but that's just me.

 

[Deleted member 214]

If you swap to the A body setup (F body - Volare, Aspen, etc. parts work too and may be cheaper/easier to find) keep your old drum parts. That way you can always go back if you want, and if you sell it someday to a purist having the original parts can only help the sale.

 

[69 Runner]

Don't ask him how he knows that:grin:

 

[71gtx]

hi the 71 383 hp 383 2bbl heads are 346 71 440 hp 440 4bbl 6bbl 71 440 not hp 346 so the head s are same ones

the springs on a 383 hp are red with a dampers which are called magnum springs. The 71 440hp 4 & 6 bbl use hemi springs with damper s which are black and heavy duty rockers. That's the difference. the 71 383 2bbl and 440 not hp have green springs no dampers:grin: