318 Build Stock++

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mickey_bigdaddy

mickey_bigdaddy

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The car is a stock '73 Dart Swinger with a 318 2bbl, 904 trans, pwr steering, pwr front brakes, and 7-1/4" rearend with 2.76 gears. I'm planning to do a little more than stock 318 rebuild right now, mainly just want to go with a little more performance than stock for the street.

Been reading a lot of ideas on here and think I have come to what I want to do based on what I have laying around and what I want from the motor and my budget. I'm planning on having some fun with the Dart and then selling it off.

I have decided to go with the following and am looking for inputs on what is good and bad.

1. Stock 318 block, crank, pistons with typical clean, flux, hone and reassembly. Polish the crank and new rings, plugs, oil pump, main & cam bearings, and hardware.
2. Summit 340 camshaft K6901 kit (with hydraulic lifters) with specs. .441/.441 lift and 276/288 advertised duration, RPM Range:1,800-5,500
3. '86 4323302 heads with bigger 1.88" & 1.60" valves, Comp Cam springs #911-16, and stock 318 pushrods
4. Mr. Gasket #720-1121G head gasket with compressed thickness .028"
5. Stock '84 360 intake manifold with 360 intake gaskets
6. Stock ThermoQuad carb smaller primaries, 1-3/8" (really want to work this out since I want this carb for my upcoming 340 build)
7. Stock ignition
8. Stock 904 automatic
9. Hedman Tight Tubes Hedders #78500 & dual exhaust w/something other than Flowmasters, kinda tired of the sound.

Ok, let me have it! :prayer:
 
Make sure you trust your exhaust shop-fitment with those headers is tight. For what you're wanting to do, 2 1/4" pipes should be fine...and I'd recommend a late model mini starter to facilitate header fitment. If you haven't already found it, look for the thread on those headers in the exhaust section...lots of good info...
 
I like the combination you picked for the motor, however, I would personally use a better brand of camshaft than the summit. I would use the Mopar performance cam of equivalent lift and duration. The TQ will work great, just a little more time consuming to tune. I did a very similar 318 using a 340 cam and it ran strong at 40 degrees full advancement on ignition timing. Also, just so you know, with those heads and stock bore along with that size of cam, the headers will help but not an absolute necessity. With a stock torque converter and 2.76 gears, headers will actually hurt the low end. Those headers will only help your particular build at the upper rpm's. By the way, I shifted my build that was very similar to yours at 5500 rpm (with headers).
 
318willrun said:
I like the combination you picked for the motor, however, I would personally use a better brand of camshaft than the summit. I would use the Mopar performance cam of equivalent lift and duration. The TQ will work great, just a little more time consuming to tune. I did a very similar 318 using a 340 cam and it ran strong at 40 degrees full advancement on ignition timing. Also, just so you know, with those heads and stock bore along with that size of cam, the headers will help but not an absolute necessity. With a stock torque converter and 2.76 gears, headers will actually hurt the low end. Those headers will only help your particular build at the upper rpm's. By the way, I shifted my build that was very similar to yours at 5500 rpm (with headers).
Click to expand...

Do you have a part number for that Mopar perf. cam? And, I'm going to do something about the gearing, just not now. How much do you think the low end will suffer?
 
FWIW, you could get with RustyRatRod to help tune your TQ...word is he's pretty good with them.
 
just PM him and see if he can help you out-I know he's offered his assistance before.
 
txstang84 said:
Unless he's talking about this one...

http://www.summitracing.com/parts/dcc-4452761ae/overview/make/dodge


Yes, this cam is awesome for a small block. It does not idle rough. It idles as smooth as a stock 340 or 318. It pulls up to 5800 rpm and offers good low end torque. Not the cam you want if you are shooting for 11's, but is plenty of cam for a mild street small block. If you get a good pair of flowing manifolds along with dual exhaust, that is what I would run. However, when you step up to a better gear and perhaps a 2400 or so stall converter, then you can easily add headers. Never go cheap on a converter if you should ever decide. I know a lot about TQ's, just hard to explain it all by typing in threads
Click to expand...
 
good flowing manifolds...that's gonna be fun to track down. Last time I checked, the 340HP or 92-93 Magnum manifolds are the best bet there, and HP manifolds would cost as much or more than those headers. Magnum manifolds would probably be the better bet, but you'll likely have to do some junk yard diving...of course, there are many around H-town you could check out. They also need some grinding to clear the steering components.
 
As far as exhaust manifolds on a A-body goes, the kicker is if you have power steering or not. If you don't have power steering, then your options for manifolds become much easier. But, I wouldn't make work out of it, just a set of 360 manifolds or even your 318 manifolds you have now will work. Or early small block B-body manifolds (if you don't have power steering). Like I say, lots of options that are "low-dollar, 20 dollar" options. I'm just saying with your current gearing and converter, you would probably like even your stock 318 manifolds better than headers. I personally did a project like yours in a '72 demon (except this 318 had the .474 280 duration cam). With factory 904 converter and 2.76 gears, I liked it better with the manifolds. ONLY at rpm's above approximately 4000 rpm's did the headers start to make a difference. But the headers took away my low end stomp.
 
Thanks guys.

So I went to look for my stock exhaust manifolds and I lost one in the move. I am missing my driver's side one, #3614395. I still have my right one, #2843953. I guess I'm heading to the junk yard to see what I can find.

Also, I did look up the Mopar Performance Purple Camshaft Kits #P4452761AE @ Summit Racing and it looked similar to the one I originally had chosen in my original list so I'll probably go with it. What valve springs should I use?

Any idea where I can get a complete list of exhaust manifold casting numbers so I can determine what cars I need to be looking at? All I have found only goes up to 1973. I know there is a 1976 Aspen & a 1986 5th Avenue, both with 318s, and a bunch of trucks in my local junk yard. Pretty sure both are power steering cars like mine.
 
If you have power steering, you will need to find an A-body manifold. But, you can always try one from the cars mentioned above and see. The drivers manifold is the sticker because it goes up and over the power steering box. I bet you could post in the parts thread of this site and someone would have what you need for cheap. If it doesn't matter to you, go with manual steering :) ! Very easy swap. Just need the box. Your steering column will even work. Hey, there is a 40 pound diet, one less belt (2 hp), and more room under the hood and a better flowing manifold will work great because you won't need the up and over manifold..... more room for headers when it is time for them too.... lol
 
Mo-Par said:
I would run 3:55 gears with that cam.
Otherwise it will seem a little lazy .
Click to expand...

For sure 3.55 gears would help, especially vs 2.76. However, with a dual plane intake, small port heads, and a 340 size cam, low end torque should not be a problem. The factory 904 converters are usually around 2000 rpm stall which will help. The car is light, and if he goes with manifolds instead of headers, I think he will be happy. If he decides to step up to 3.55's, I would also advise stepping up to an 11 inch 2400 stall converter and headers too. At this point, he would have a very quick A-body for a mild 318. :)
 
318willrun said:
For sure 3.55 gears would help, especially vs 2.76. However, with a dual plane intake, small port heads, and a 340 size cam, low end torque should not be a problem. The factory 904 converters are usually around 2000 rpm stall which will help. The car is light, and if he goes with manifolds instead of headers, I think he will be happy. If he decides to step up to 3.55's, I would also advise stepping up to an 11 inch 2400 stall converter and headers too. At this point, he would have a very quick A-body for a mild 318. :)
Click to expand...

Ok, this getting more expensive. I'm now considering going back to stock w/just 302 heads, the 4 barrel TQ and dual exhaust. Remember, I'm just wanting to get this car on the street before it goes up for sell.

Pisses me off that I lost my driver's side exhaust manifold those suckers are expensive on eBay. I've looked at the A-Bodies classifieds and not too many there either.
 
If you lived near me i would give you an a body manifold.
They are pretty common, shouldn't cost more than $20 for one.
 
mickey_bigdaddy said:
Ok, this getting more expensive. I'm now considering going back to stock w/just 302 heads, the 4 barrel TQ and dual exhaust. Remember, I'm just wanting to get this car on the street before it goes up for sell.

Pisses me off that I lost my driver's side exhaust manifold those suckers are expensive on eBay. I've looked at the A-Bodies classifieds and not too many there either.
Click to expand...

This is no more expensive than your original thread. You were planning on the TQ, cast intake, cam, and 302 heads. None of that has changed. You mentioned that you were planning on upgrading gears, we suggested 3.55's. I only suggested an upgrade on a torque converter, but it isn't necessary. I will tell you this, that usually you never get out of a car what you put into it if you are building them. In other words, if you want the most out of your Swinger, just throw in a 150 dollar 318. The next buyer will probably yank the 318 you build anyways for whatever they have in mind.
 
My Demon has most of the same combination that you are putting into your 73. The Summit cam is a Crane Fireball. It's an older grind, but still good for street work and is easy to live with. The cam will work well with stock valve springs. If you want to be sure use the 340 valve springs or P4120249.

Suggest you look into a shift improver. Transgo offers a product range, any can be installed without removing the tranny. I'm using the TF-1 and enjoy the crisp but not harsh shifts.

When you get your engine rebuild kit, ask for 67-70 spec pistons. The later piston sits lower in the hole. Even without milling the heads, these ought to give you better than a 9.0:1 compression ratio.

If you really want to enjoy the extra power, dumping the 2.76:1 rear needs to happen. Suggest a 3.23:1 or 3.55:1. Less, no fun under acceleration; More, no fun under steady state cruise.
 
Agreed on the gears, trans work, 4bbl intake, and mild cam...hey mickey, does the engine "need" to be rebuilt?
 
I would recommend using Rhoades lifters with whatever cam that you choose. They will make it idle smoother, more idle vacuum, better MPG, and stronger off the line.


I ran a similar build. 72 318 block, TRW 10.5 forged pistons, 77 360 heads with 1.88" intakes, stock 340 cam, Rhoades lifters, stock 69 340 4 bbl intake, stock exhaust manifolds, 2 1/4" exhaust with h-pipe, and a Holley 600 vac secondary carb. I got 17.75 MPG highway with a 7 1/4 axle with 2.76 gears.

UPGRADE YOUR AXLE! I blew up 3 of the 7 1/4" axles in 4 years with that combo in my daily driver (not very radical either). After switching to a 8 3/4" axle, I drove the car to 500,000 miles without needing any more axle work. Those 7 1/4" axles can't handle much over a stock 318 2 bbl... :banghead:

If you use 10.5 compression pistons with a 340/360 head, the larger combustion chambers will get you down to 9.2 compression and able to run cheap pump gas. With stock 318 heads, I had overheating problems above 80° F outside. I had to install the 360 heads to bring the compression down to reasonable street levels.
 
, TRW 10.5 forged pistons
Click to expand...

These are still made?

I know KB still makes a dome piston, but didn't know TRW did...

That being said, CR is not required to build a fun driver. My 5.2 Magnum is totally stock with an Air Gap intake, Hedman tight tube headers...stock converter, 2.76 gears, and it's plenty fun to drive...or it was before I stored it. You're encouraging him to pour money into a vehicle that will only be sold shortly thereafter...kinda counterintuitive.
 
txstang84 said:
These are still made?

I know KB still makes a dome piston, but didn't know TRW did...
Click to expand...


Those were old that my brother bought back in the 80's and gave me with a short block. I don't think that they are made anymore, but were nice, flat top with valve reliefs.

But if you can find a 10.5 piston for a 318, they will also do, doesn't have to be the old forged type, that's just what my brother bought for the short block that he gave me when he planned to build it, then later didn't need it.
 
Ok, my original post is getting changed now based on all this feedback. Thanks to all!

First, I just spent the afternoon at the junk yard pulling the stock exhaust manifolds ($30) that were with on the 302 heads I just bought so that problem is solved there, I think. I already have the intake and TQ, not cost on those.

On the gears, anyone have a cheap option, maybe a salvage car to obtain them from?

Yes, the engine needs a rebuild. It's caked in oil buildup and the previous owner took it apart and gave up so it's in pieces already. The pistons look good so I don't want to change them.

I think I'm going to go stick with the Summit cam and change the valve springs.

And I'm going to sell this car soon so I don't want to put too much into it. I just want the thing to run for a while for me and then enough for someone else to want it. The car is very very clean so I think someone will like it for later.
 
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