70 duster project

[duster 344]

Starting the 70 duster project, Manley gathering parts right now. I found the duster a month ago, it’s a factory 318 car. Has a cast 833 manual swapped in it already and a healthy rebuilt 318 from seventy five. Still has the factory 742 sure grip with 323s. Needs a little bit of body work, and new carpet inside. it’s all there and in pretty good shape for Minnesota. Going to b cold here soon, I plan on spending a lot of time in the heated shop.
With what I have in the shop right now, the duster will receive a steel crank 340, 30 over, with 11.5 direct connection pistons 2.02 heads. A 268 cam, 492 lift, flat tappets, and a performer intake with a 750 double pumper. 1 5/8 full headers, 2.5 exhaust with flowmasters.
Changing out the 323s for 391s and putting a big set of 28 inch tires on the back, that’s the plan right now.

 

[duster 344]

So I’m back in the shop, I’ve learned that the duster has 276 gears in the rear end from being an automatic car in its past life, I miss quoted the cam I have, it’s the high energy 268/.454 cam, been out of the game sorta speak for a while. Really exciting getting back to it. Speaking of which, got the old 340 tore down, been sitting in an undisclosed location for about twenty years. Sad! I know. Every thing looks really good, but. I found some potting on the cylinder walls. Was just going to get some gaskets clean it up. Now it looks like a bit of a different plan?

 

[duster 344]

A little back story on the motor if anyone is interested, I always like the history behind things. My friends dad had this in his shed for a long time. It came in his 68 challenger. He built it and crashed it not long after. The car was parted out. All that was left 20 some years latter, when I showed up. Was a 340 block, the crank, connecting rods, and a set of direct connection 11.5:1 pistons. I bought it from my buddy’s dad for six hindered bucks, with my tax return at 18 years old. I was going to tech school and needed a project. I perchased an old 318,and a 360 out of a van so I would have all the parts I needed. Not knowing a whole lot, and on a budget. I got a rebuild kit, with upgraded cam, and put it all together. Set of 596 heads and stock four barrel intake, from the 360. Harmonics balancer, timing cover, oilpan, flex plate and converter off the 318. The 360 came with a 727, and I got the k frame with the 318. I put it all In a 81 Marada, that came with a slant six. Stock exhaust manifolds and a crappy dibble pumper, badly in need of some work I scored off my brothers car. That boat was to big and to new for what I wanted. I sold the car, and the transmission. Kept the motor for something better. Didn’t have much money, got into construction and had a daughter. Twenty years later still don’t know a whole lot, still don’t have a lot of money but could pass up this 70 duster when I found it.

 

[duster 344]

So back at the ranch. I have a buddy with a machine shop, that’s going to cut the 2.02 valves into those 596 heads, thinking we might have to go to 40 over, on the cylinders. I’ve honed them out once already, tried to clean them up with the try hone: meybe the dingleberry will do it? Was going to mic the cylinders tonight but can’t find mi micrometer. Guessing I borrowed it to some one and never got it back. If I have to go to 40 I guess I’ll have some nice pistons for sale. But if I’m getting pistons, I might as well get the rebuild kit. Think it would be worth it to go to a bigger cam? I’ve got the 268, I could spend a little bit more on the motha thimper meybe. Basically street strip car. 4 speed with probly 3.55 gears and 28s

 

[duster 344]

It’s been a while, buissy times. But, moving stuff around in the shop, my girlfriend and I might get the 318 out of the duster this weekend. I came across this old corner glass with the playboy sticker on it. I remembered my cousin having one like that in his Camaro. I started thinking of all the things that window probably seen in its lifetime. Cruise nights up town, gathering of friends around cars on warm summer days in yards and parking lots. Memories long lost I’llb a pile of dust and I tilt parts in the corner of a garage some where. I think that’s probly why we do what we do, to relive some of those memories, and to make new ones, just wanted to say thanks for this sight everyone, great place to share stuff like this. But I better get back to work so I have something real to post in the next couple days

 

[duster 344]

Spent a few hours in the shop yesterday. Got the 318 ready to come out. My cherry picker took a crap on me, sat to long or something. Going to borrow one today I hope. Was a good time though pulling bolts with my girlfriend. Her small hands work good for header bolts

 

[Moparone]

Following. Looks like a great project. Looking forward to seeing your progress

 

[duster 344]

Got the 318 out yesterday, separated the transmission. That all looks brand new. The clutch and pressure plate, through out bearing all were recently put in there. So I’m happy about that. I decided to see what was in the 318, while Jade took more lights and wiring harness out. And started stripping the doors

 

[duster 344]

 

[duster 344]

Was a good running 318, looks like it was running rich with that 750 Holley, I’ll have to see what jets are in that. I’m not sure what the cam is. I did some looking on line. It has (Wilson 30012HY) scribed in it. Could be a local grinder, I don’t know. Has anyone heard of that? Anyway, I’ll have to order some parts for the motor, still waiting to get the 340 to the machine shop. Meanwhile where going to keep pulling the duster apart. A couple patches on the rear quarters, which I’m having trouble finding. Then off to get sandblasted and primed. All in all no big issues yet

 

[rumblefish360]

I think it’s great that your girlfriend is getting dirty along with you. Keep your temper and don’t yell! My wife and I still turn a wrench together. I started dating her at 15. She’s 52 now. She can drive the socks out of a 4spd and has no issue swinging an engine in & out or doing brakes.

Those old 11.5-1 pistons, if reusable, will almost certainly require a race fuel to run. The cams you mentioned are driver cams and with that piston, I don’t think it’ll make a very happy or wallet fuel friendly street engine. It’ll create a lot of cylinder pressure. Or AKA, BIG cam friendly.

With 3.55 gears rolling a 28” tire, I suggest a cam no larger than 230@050. Also a reduction of compression (AKA New pistons) of ether the replacement style or slightly lower compression style of a flat top.placed at zero deck height.

Duster metal, at least new replacements are sometimes difficult to find. AMD has discontinued some metal parts. Also, yes, that could be a local grinders cam stamp.

 

[duster 344]

I’m always open to suggestions, I have a basic understanding of how it all works, but haven’t built alot of engines. I’d like to break 400 hp with the 340. I’ve been looking at the thumper cam. 295/312 advertised .507/.494 lift thought that would be more fitting with 2.02/ 1.60 valves, may have to look into some different gears but I haven’t bought them yet either. Just thought the 3.55s were a happy medium

 

[340sFastback]

Here are some tips on a mild 340 build:

1970 340 High Performance Mill Dyno - Mopar Muscle Magazine

Also, if your carb is running rich make sure the transfer slots are not overly exposed. Otherwise it will be excessively rich at idle no matter what the jets are.

 

[rumblefish360]

I’m always open to suggestions, I have a basic understanding of how it all works, but haven’t built alot of engines. I’d like to break 400 hp with the 340. I’ve been looking at the thumper cam. 295/312 advertised .507/.494 lift thought that would be more fitting with 2.02/ 1.60 valves, may have to look into some different gears but I haven’t bought them yet either. Just thought the 3.55s were a happy medium

What’s the overall goal of the car? Just a hood streeter it seems like.
3.55’s are everyday performance street gears. I run them in my car, the wife’s and my sons truck, all 360 powered.
(If there back by an overdrive, there really good.)

If your using the flow masters for there sound, OK fine but I’d would run a DynoMax or Summits turbo muffler, (best turbo muffler) or a Hooker Aerochamber, best Chambered muffler and awesome sound or a straight through Hooker or Dynomax “Maxflow” muffler. Glass pack ish style.

 

[duster 344]

I’m definitely going to drive the car, mostly weekends. Pretty rural around here, more 60 70 mph than stop light to stop light. I’d also like to take it to the track for test and tune just for fun, using the flowmasters because I already have them. Probly get a set of cut outs to. Trying to make the most of what I have without buying a bunch of parts. I know horse power cast money. And toys cost money, and having fun in general cost money, But if I can make a lot of fun on a budget that would be better. I have to buy a set of gears, probly a cam. Obviously a rebuild kit. Which could include pistons. I’ve been looking at a lot of threads on here, trying to figure out my best combination, it’s an on going thought process with everything I learn

 

[rumblefish360]

Skip the cut outs, they’re almost always a power looser unless you scientifically figure it out on a dyno. You would be a world ahead of you follow David Vizards exhaust example recommendations for sure!

That would be a header extention into a pressure wave cancellation box, each box being at least 360 cubic inches necking down to the exhaust pipe into the mufflers.
Big difference!

A lot about making horse power is now well the cylinder heads flow in AND out. This would be why the Trick Rlow heads gets the nod by many here since it’s a very good high flowing head that is t a bank breaker. A bit more pricey than an Edelbrock head, BUT! It’s already CNC ported and it will make the most power with what ever cam you use.

Speaking of a camshaft…. I’d have one on a LSA at 108 in that 340. A cam at 230@050 (give or take a few degrees) would be pretty good with the 3.55’s.
Use as much lift as you can get to take advantage of the cylinder heads air flow capability.

With a stick shift car, I myself would run a mechanical cam. Look at Hughes engines for starters. Also Howard’s cams and Schneider cams. Remember it’s only a few bucks more to have one custom ground with melts away as time and usage go on.

 

[duster 344]

I appreciate the info, I’ll look into it more. The plan with the 596 heads is to duplicate an x head cutting in the 2.02s some porting and a little shave to get in the same cc range, not shure if it’s real important at this stage to offset lift and duration to get a little more on the exhaust side

 

[duster 344]

Tonight was a bit of a learning experience. Got most of the doors stripped down. Basically focused on getting the body ready for paint till I can get in the machine shop

 

[rumblefish360]

I appreciate the info, I’ll look into it more. The plan with the 596 heads is to duplicate an x head cutting in the 2.02s some porting and a little shave to get in the same cc range, not shure if it’s real important at this stage to offset lift and duration to get a little more on the exhaust side

With those head I’d just kill them flat. If you start to mill them down a bunch, you’ll need to mill the intake as well.

I’m not catching the cam lingo here. But there’s plenty of time for cam selection later.

Concentrate on the body.

 

[duster 344]

Working on the doors again tonight, the car at one point was dinged in the drivers side. There are two different year doors on it. And they have different Hard ware in them. So a learning experience on bothe sides the car

The driver side had bottom style connectors on the window, and they were stripped out. Had to grind a few screws and drill on out.

keep in mind that I am not a body guy. But I’m going to have to find some parts. If anyone can steer me in the direction of what year this door is, or where I can get the window seals for the door.
To bad that the girlfriend had to work. It’s definitely more fun with her working in the shop to. And she’s way better at marking and tagging parts then I am there’s a bit of a mess of parts there now, I’m sure she’ll appreciate me including her in the experience when she gets back. But I got the doors stripped down.
The rocker was damaged the same time as the door. They replaced the door and tried to mud in the rocker.

have to consult my body guy

 

[B-i-n-g-o]

When I was a kid, maybe 74-75, so not 100% on the details, my brother had a 70 340.Duster in yellow. He tore up one side drag racing it on back roads (a buddy thought the clutch was too loose, so tightened it, but didn't tell him, so he lost it on launch). He bought a parts car...it was green with the black hood, like yours. I always thought he should've pulled the drivetrain from the wrecked yellow one and built the green one...I like that scheme!

Good luck on it!

 

[rumblefish360]

I really dislike when I find crap like this.

 

[B-i-n-g-o]

Cool car messed up due to young and foolish? Agreed, sorry, didn't mean to bring it down. I'm just saying that body in green with black and a 340 is going to be mighty nice!

 

[rumblefish360]

Cool car messed up in youth? No, no issue at all. That’s youth for starters and I don’t fault anyone for mods or what needs to be done like replacing doors after a fender bender.

It’s when I discover things like swapped doors but different years with minor differences. While it works, it just will make something harder later. Finding parts maybe? Just simply remembering all the little things added to the whole car is a PIA sometimes. Knowing up front is nice when I purchase the car. That’s not always possible.

Doing it myself is what I like to avoid. Modifications for a Hotrod or road course and etc… are one thing. I really don’t mess and swap around body panels and interior. I like to keep the electrical mods to a min.

 

[duster 344]

Yesterday was a good day. I got done with work early, got to she shop and started with the gas tank and bumpers. Wanted something easy after the whole door thing
The girlfriend got back and we took out the interior, side glass and door trim. Looks pretty good under all that.

and the cigarette light is still there, looks like it’s in nice shape yet. Took out the stereo from 1996 and all the extra wiring. The aftermarket gauges where patched in underneath but didn’t hack up the the factory harness too much. That all looks pretty good