How streetable is this 1970 Duster?

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fernando.

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Hey all. I’m new here.

I’ve been an import guy my whole life. Shame shame. But now I’m looking at buying a 1970 Duster - I would just like some opinions on how streetable this is. I’m not planning on going on far drives. Maybe church with my family, ice cream runs, back and forth from my shop the odd time. All in town with speeds less than 55mph.

1971 Plymouth Duster
Was a Slant 6 car

Engine:
318 bored .030 over
10.9:1 Compression
Purple Shaft .508/292 Camshaft
Eagle 6.2cc Domed Pistons
Eagle Crankshaft
Eagle H-beam Connecting Rods
Holly Sniper EFI w/Fuel Cell in Trunk

Transmission:
A833 4 Speed Transmission

Rear End:
8 3/4
4.30 Gear Ratio

Please excuse any misinformation. I’m still new to the brand and just going by what I’ve been told.

Cheers.

B2-D01-A15-FCA2-4-E34-8-F3-B-6-CA59-B110512.jpg
 
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No long highway trips with that.... Unless you like hearing that motor buzzing. Is it "street-able", sure, it's all in what you can tolerate. If the car is in great shape, a cam and rear gear change would make it a good driver. High octane only (91-93). This is my $0.02
 
85glht said:
No long highway trips with that.... Unless you like hearing that motor buzzing. Is it "street-able", sure, it's all in what you can tolerate. If the car is in great shape, a cam and rear gear change would make it a good driver. High octane only (91-93). This is my $0.02
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Rear gear I understand. I'm sure some 3.55's or 3.92's would be better.

What's wrong with the camshaft?
 
That camshaft needs low gears and a stall or a 4 speed to be happy. It won't make much low speed torque. Probably couldn't fall out of a tree at less than 4000rpm. I would be more worried about what octane gas you have available (especially in the hot months).
 
496 polara said:
That camshaft needs low gears and a stall or a 4 speed to be happy. It won't make much low speed torque. Probably couldn't fall out of a tree at less than 4000rpm. I would be more worried about what octane gas you have available (especially in the hot months).
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It's a 4 speed car with 4.30's.

Here in Canada we have 91, 93 and 94 readily available at any station, year around.
 
Sure, it is streetable. Depends on what you can tolerate. I have 3:91's in one car, 4:10's/4:11's in 3 other cars, and 4:88's in another car. All street driven.
 
I would run it the way it is and run the highest octane you can get, see how you like it first. With comp 11-1 and that cam you want rpms and a good tune to stay out of detonation, if you don't like the rpms look up a chart with taller tires to see if that can help. The lowest set of gears would be 3.91 with that combo all depending on tire size.
I would make sure it has disc brakes up front if not It's an easy upgrade.
 
6PKRTSE said:
Sure, it is streetable. Depends on what you can tolerate. I have 3:91's in one car, 4:10's/4:11's in 3 other cars, and 4:88's in another car. All street driven.
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Great! Thanks for the input. Looking for something a little more "rowdy" than a factory car but not a full drag car. Won't be spending more than 30min at a time inside in this car, ever.
 
moparlvr166 said:
I would run it the way it is and run the highest octane you can get, see how you like it first. With comp 11-1 and that cam you want rpms and a good tune to stay out of detonation, if you don't like the rpms look up a chart with taller tires to see if that can help. The lowest set of gears would be 3.91 with that combo all depending on tire size.
I would make sure it has disc brakes up front if not It's an easy upgrade.
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Thanks for the most in-depth response so far.

All of my driving will be within 15-30min one way, all in town, stop light traffic, no real "cruising". I don't mind something a little more "rowdy".
 
85glht said:
No long highway trips with that.... Unless you like hearing that motor buzzing. Is it "street-able", sure, it's all in what you can tolerate. If the car is in great shape, a cam and rear gear change would make it a good driver. High octane only (91-93). This is my $0.02
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Cam is a bit more than I would want, but should be ok with a 4 speed. I wouldn't plan on going over 55 mph for any distance with that much gear, but it should be a really fun car.

BTW, welcome from Alberta.
 
fernando. said:
Okay? Thanks for zero explanation.
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The compression is going to force you to run high octane fuel. The cam requires a non street friendly gear (It'd be a pooch out of the hole without them). A lot of parts would have to be changed to make it street friendly.

It would be an absolute riot in town/stop light to stop light!
 
Your explanation of your expectations in #11 mean that thing is perfectly streetable FOR YOU, as is. You will need the very best pump gas you can find. (Aasuming it won't be your ONLY car/daily driver)
When I was younger, (WAY younger!) and a real hot rodder, I drove a 57 chevy with a 400hp 350/4sp/4.56 gear daily to work. But I had a 3.08 center, and quieter mufflers when required.
My occasional street driver has a 500hp 440, 4500 stall, and 3.91s. Perfectly streetable..... occasionally.
Edit: the green Duster? I'd burn those rear tires to the ground, then replace em with tires about three inches taller. Effectively reduce that rear ratio a bit.
 
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skep419 said:
The compression is going to force you to run high octane fuel. The cam requires a non street friendly gear (It'd be a pooch out of the hole without them). A lot of parts would have to be changed to make it street friendly.

It would be an absolute riot in town/stop light to stop light!
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I'm not looking for a daily driver at all. Just something FUN to roast the tires, go to church in, head over to my shop, everything is within 15-20min - stoplight to stoplight - there's almost no cruising.
 
33IMP said:
Your explanation of your expectations in #11 mean that thing is perfectly streetable FOR YOU, as is. You will need the very best pump gas you can find. (Aasuming it won't be your ONLY car/daily driver)
When I was younger, (WAY younger!) and a real hot rodder, I drove a 57 chevy with a 400hp 350/4sp/4.56 gear daily to work. But I had a 3.08 center, and quieter mufflers when required.
My occasional street driver has a 500hp 440, 4500 stall, and 3.91s. Perfectly streetable..... occasionally.
Edit: the green Duster? I'd burn those rear tires to the ground, then replace em with tires about three inches taller. Effectively reduce that rear ratio a bit.
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Awesome! Yes, we have 91, 93 and 94 available at almost every gas station all year round.

I have a Carli suspension equiped Ram 2500 and my wife has a 4Runner that we use for family stuff. This car is purely, get in, have a smile and coke, and live a little. No 1hr+ road trips or cruises.

Sounds good! That would be my plan, eventually getting a taller tire in there. Not sure what I could squeeze in there, but that would be the best plan!

Edit: I'm just a 32 year old on a budget! I don't have the luxury of immediately swapping cams, gears, etc. So if everyone steers me away from it, I won't buy it. A set of tires eventually is no problem however.

Cheers.
 
It looks like a nice car. That cam is a really poor choice for a 318, but with compression and gear, it will certainly be rowdy. You will probably be completely happy with it the way you plan to drive.
 
fernando. said:
I'm not looking for a daily driver at all. Just something FUN to roast the tires, go to church in, head over to my shop, everything is within 15-20min - stoplight to stoplight - there's almost no cruising.
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For stop light to stop light it's perfect.. i run the same gears but a bit more cam... streetable is relative and everyone has a different definition... I personally will probably drop my gears from 4.30 to 3.73 or 3.55 when i do my next motor.. the 4.30s are fun but in my area if you aren't doing 70 in a 50 you are in the way..

If that cars a good deal i would snatch it up.. i kinda wanna get rid of my b-body for a duster at this point.

P.S. i run 30" rear tires... yours look around 26" so your rpms will be a bit higher. It isn't bad but does get a bit old. If you do drop down i would go to 3.73 not 3.91. but it's all personal preference
 
NC Engine Builder said:
It looks like a nice car. That cam is a really poor choice for a 318, but with compression and gear, it will certainly be rowdy. You will probably be completely happy with it the way you plan to drive.
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Cheers man.
Yeah, church is the next town over - 20min stop lights.
Going for a quick rip around with my kid/wife would all be in town.
My dealership is a 7min drive from my
house and all stop lights as well.
 
Icetech said:
For stop light to stop light it's perfect.. i run the same gears but a bit more cam... streetable is relative and everyone has a different definition... I personally will probably drop my gears from 4.30 to 3.73 or 3.55 when i do my next motor.. the 4.30s are fun but in my area if you aren't doing 70 in a 50 you are in the way..

If that cars a good deal i would snatch it up.. i kinda wanna get rid of my b-body for a duster at this point :)
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Thank you for the response!

Everyone here is very helpful and friendly so far.

Not like that in the import world. Lol
 

fernando. said:
Thank you for the response!

Everyone here is very helpful and friendly so far.

Not like that in the import world. Lol
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well.... you haven't had any of the meaner guys respond yet is all :)

BTW... Radial T/A's are horrific tires... with that gear and limit on the tire size get some ET Streets on the back of it or you will be pretty much driving on ice...
 
BTW... since you don't know mopar... the main thing to check on that will be the transmission crossmember.. you will see 2 bars going from it to the front suspension.. on salt belt/northern cars the crossmember likes to rust out there and will be a major problem.. all fixable but just the 1 thing you really wanna look at...

Also.. if you ever take it apart do not paint the engine bay black.... always body color. And a clean/pretty engine bay matters more than the outside of the car :)
 
What cylinder heads are on this? If aluminum, then fuel requirement isn't as critical. 4spd and 430s in town will be a blast. Dad ran 4.56s for 120+ mile trips. All depends on what you can tolerate. For me, 3.91 are ok for short highway, but like the 3.23 for my driving.
 
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