318 temp use

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moparmat2000

moparmat2000

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I am building a 67 4 speed barracuda. I have a dissasembled 360 short block and bare aluminum heads. I was planning on a 408-410 stroker. For now though i was thinking of using a 1974 318 i have from a granny fresh 4 door dart parts car. This engine ran good, no knocking, and didnt smoke. Was parked because of timing issue in the distributor, vac adv didnt work, mechanical adv weights were frozen in place by old sticky grease. I was wanting to swap it later into a 69 barracuda future project car i have for my son and i.

So heres the questions. I didnt want to get too far into this engine money wise. I was thinking make sure the crank was piloted for the input shaft bushing, or drill it out a bit deeper if needed and use a dakota bearing (i wont cut the input shaft on trans). Install a new timing chain and use an automatic tensioner from a dakota. Original chain is slopped out. Pull the oil pan and clean it out, put a new oil pump, install new brass core plugs, seals, gaskets etc. I dont have the 2bbl intake or carb anymore, recommendations on a used 4bbl intake, and what 4bbl carb size to use on this thing. I dont want to dump a ton of cash in this thing. I just want to get the car on the road faster and use the cash earmarked for the 360 to get other things done it needs. Car will have an A833 O/D box, and 3.73 gears. 68 340 exhaust manifolds and dual exhaust.

Should i add a mild cam and lifters to it? Pop the rods and mains and look at the bearings? This engine down the road will end up in the car of a new driver when i build my stroker, so i dont want to go nuts with it.

Any thoughts?

Thanks
Matt
 
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Rumble; feel free to skip to the bottom line.......lol.
Car will have an A833 O/D box, and 3.73 gears. 68 340 exhaust manifolds and dual exhaust.
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I did just about exactly that, except no stroker. The teener was my winter motor for 5 years running.
All I did was; oil pressure test,compression test, cooling system pressure test. She passed them all. I put a 340 chain kit on it,no tensioner, a TQ and intake, and used the TTIs from my summer screamer;that's all.No cam.My engine was a 73; is actually, I still have it,now in another project.
I ran that combo with 4 or 5 different transmissions, and many different rears. One of my favorites was the A-998 with the 2.74 low-gear and a 2800TC, and 3.55s. Well, there was no loser combo. I ran it with the same exhaust as was on the 360 summer engine,namely;TTIs and dual 3" all the ways with an H-pipe. You have got to try that! That 8/1 engine sounds soooo mellow at full-song, thru dual 3s.

Anyway, the point I'm working up to is this;try to resist the urge to throw a cam in it.That 8/1 engine really isn't an 8/1. The cam that's in it makes good cylinder pressure, and so the low-end is pretty good. At WOT and after about 3500 it makes reasonable power.But;
That od trans has very wide ratios, wider than anything you can bolt on there, short of a trans from a grain-truck. 3.09-1.67-1.00-.73od, with splits of .54-.60-.73
Now, if you put a bigger cam in her, she will lose cylinder pressure;guaranteed. And that will show up as a soggy bottom end. Your 3.73s will help get you thru that.
If you put a 262 (a typical choice);for low-ET she will want to be shifted at 5500ish, making the drop on the 1-2shift to 2970. That would be a powerband requirement of 2530. Teener can't hardly do that with the meager cylinder pressure it's gonna make. So it will feel soggy. But if you shift it at 3000 in cruize-mode, the Rs will drop to 1620, and again, the meager cylinder pressure will mean that you have to open the throttle a lot further than necessary, just to continue accelerating from the current 21 mph to cruise speed in second.
I just can't stress this enough; with that od trans, please stick with the factory cam.
If you had a lighter car, like an early-A, then you could maybe get away with a mild cam, but the 2nd gen Barracuda is the tank of the As, with p/s, p/b,aluminum top end and wheels,plus full interior, mine weighed in at 3450 with less than a half tank of gas. This is 10.85 pounds per 318cube, pretty mundane. The early As are about 350/400 less so in them, this is 9.59, fully 12% better. That's like adding 38 cubes right there!

Heres a quick comparo;
This is a stock teener with the 240/114 cam in it
Static compression ratio of 7.8:1.
Effective stroke is 2.89 inches.
Your dynamic compression ratio is 6.93:1 .
Your dynamic cranking pressure is 132.46 PSI.
V/P (Volume to Pressure Index) is 110...............................................110VP

And here is the same engine with a 262/110 cam;
Static compression ratio of 7.8:1.
Effective stroke is 2.72 inches.
Your dynamic compression ratio is 6.58:1 .
Your dynamic cranking pressure is 123.66 PSI.
V/P (Volume to Pressure Index) is 97.................................................97VP
Notice the drop in cylinder pressure, and that the VP has dropped by 13.4%. That's like the engine just shrunk by that percentage. That's why the teener feels soggy on take off. To get it back, you will have to slip the clutch out and rev it it up to where the torque is that same percentage higher. Ideally the compression needs to be brought up,usually with pistons.
Read about VP here; V/P Index Calculation

Here is the same 262 cammed engine, now with the cylinder pressure brought up;
Static compression ratio of 9.5:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 7.59:1 .
Your dynamic cranking pressure is 149.29 PSI.
V/P (Volume to Pressure Index) is 111..............................................111VP
Notice I had to bring up the compression ratio to 9.5 to get the 111VP. So now the bottom end feels about the same as the stocker. This will make a very nice teener; plenty of torque, good power, lots of rpm, yada,yada,yada.....

With a 262 cam,the power peak might be up around 5000/5200, which with 3.73s is about 44mph.The starter gear is pretty good at 11.53;so, you don't have to slip the clutch much to get moving. But then with the bigger cam, you have to drive thru the soggy part which ends at somewhere between 3000 and 3750 where the torque peak will likely occur. Now you're starting to make power;26mph. At about 40 you're gonna shift.And the Rs will fall to 3100, back into the top of the soggy territory. Second gear will now get you about 65mph@5000.
So really, The point I'm working up to is this; with this od trans and a 262 cam, the power is from 26 to 40mph, and again from 48 to 67mph, with the 3.73s

So let's talk automatic for a bit;
Say a factory stock teener, but with an A-998 automatic, and with the 2800TC.
2800 is about where the stock teener makes it's maximum torque. So you have the potential to blast off right off the line. With a 2.74 low gear and the 3.73s, your starter gear is 10.22, about equal to the stock A904 with a 4.17 rear gear. But wait; the TC has a hydraulic torque multiplication factor, that, on the line might be as high as 1.2, making the 10.22 climb to an instantaneous high of 12.26, and that is really blasting off!.But don't get excited, this multiplier rapidly falls off to perhaps 1.05 at about 3 car-lengths out. By now, the engine is well on the pipe,the secondaries are open,and she's pulling hard.And will continue to it's powerpeak at around 4400, and you will want to shift no sooner than 4700/4800 (5000 in my case), so 38mph.(put some springs on it) So it has been making good power almost from the get-go to 38 mph. So now comes the 1-2 shift and the Rs drop to 2700,oops 2800 plus slip, and you're back in the ballpark pulling hard,and second gear is good to 60=4500ish,about where the power-peak is.
And so the factory teener is making less power than with the earlier 262* cam, but the delivery is now from 3 lengths out,to almost all the way to 60/65mph; about the quickest way ever,to 60mph,with a factory teener,lol.
So the point is this;all other things being equal; the highest average power put down, wins,especially in the fun department.

I fabbed custom bracketry to put the automatic floorshifter up through the 4-speed hole, with no gear indicator. Yeah, I counted clicks,lol.
I put studded snows on it, and there is just no way to tell you how much fun this little winter engine was.
The only other combo that came close in fun-factor was with 3.91s and with the od box and splitting the GVOD. With this combo the powerband requirement was just 1050rpm. That little teener scoots pretty good when on the pipe; ALL the way. 4.30s were pretty good too, but a little too much starter gear for me.

So, it might sound like I'm trying to steer you towards the A998, and I am. I'm a die hard stick-man since 1970. But this combo will be way more fun with the A998/non-lock-up and a 2800TC.No comparison. Especially with the 3.73s. Teeners really like a starter gear of about 10/1, and 2.74 x 3.73 = 10.22 BadaBoom!

Ok one more; stock 360 2bbl, with 252/112 cam
Static compression ratio of 8.0:1.
Effective stroke is 3.02 inches.
Your dynamic compression ratio is 6.91:1 .
Your dynamic cranking pressure is 131.95 PSI.
V/P (Volume to Pressure Index) is 120.........................................120VP

Or this one, factory 360 with a teener cam
Static compression ratio of 8.0:1.
Effective stroke is 3.13 inches.
Your dynamic compression ratio is 7.12:1 .
Your dynamic cranking pressure is 137.27 PSI.
V/P (Volume to Pressure Index) is 130.........................................130VP
you can put that 833od trans on this and drive it like a teener,lol. 130 is gangbusters. You could probable drive that with a one speed,lol.

I know this is a long rambling post,but that's the way it worked out.......lol
 
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  • With a 4-speed, I'd bump the cam up... a little. I'd say around a .450 lift and a duration somewhere around 210 -218 @ 50.
  • New gaskets, seals, freeze plugs and timing chain is great! (and a must for peace of mind). Tensioner an option.
  • "Look" at a rod bearing/main bearing. If not needed, skip 'em.
  • If it ran good, no smoking or knocking, I'd use the original oil pump
  • I'd put a Weiand action plus on top with a 600 cfm carb. (if you had access to a factory cast intake/TQ set up, I'd do that in a heartbeat).
Good Luck!
 
Fascinating.
After reading all of this, what advantage would a bone stock teener with headers be with a 4 speed O/D?
What about a bone stock teener with a 2 barrel carb and headers?
Or would stock exhaust manifolds be as good as headers at this power/flow/stock cam combination?
The point that i'm getting at was that back in the day, i had a '71 Demon with a '69 318 that was totally stock including 2 barrel and stock exhaust manifolds, cam etc.
It had a factory 3 speed floor shift standard tranny in it and an 8 3/4 with 3:23 gears.
And man, it was fun to drive!
Was it just the right combination, or was it just luck?
Is a combination that the O.P. should consider?
 
I'm quite expecting it to be between somewhat of a gutless wonder, and ok. From the posts above, that wide ratio 4 speed kills it even with 3.73s. A passon 5 speed is what it prob needs, but not in the cards. Headers are not gonna happen. I cant stand them. I got 68 340 manifolds, and will use them with an accurate exhaust. Prob flowmaster 40 series. All of which i will swap over to the 408-410 stroker. Yep, that will prob hurt its performance a little, but will appear stock which is the direction i was going for. Parts are hard to find in my neck of the woods, and demand a premium, soi will use what i got. If i had a close ratio 4 speed i would have concidered 3.23 or 3.55 gears, but this one fell in my lap with a bellhousing for $200 with good gears and synchros in it.

Now since i am just bench racing this idea as a means to get further along on the rest of my project using less money, with this being a 1 or 2 day affair to fix and put together, i am just wrapping my mind around this idea. Plus with everything else thats going on in my life, i may actually get to pull out that 318 thats in my car now as a mockup maybe sometime next year.

My projects always seem to end up as stillborn either from lack of funds, no time, or i just plain run out of "G.A.S." ( Give A ****). I got a half finished 88 shelby z turbo car i last touched in 2006. Its covered w dust and boxes. Got a rebuilt engine and trans sitting pickled w marine oil and all the holes taped up w aluminum tape to keep critters out.

So if your looking for a results of this soon dartnut, its prob not gonna happen. My whole point of this was what should i do to it on the cheap besides what i already planned on doing. I have the gasket kit, a water pump, seals, brass core plugs, a slightly used timing chain. I planned on getting a 3.9L V6 timing chain tensioner and an oil pump too. My gasket kit has felpro permatorques in it, should i remove the heads and take a peek? I know if i do that, its like rolling a snowball down a hill. I will end up sending the heads out, want to hone the cylinders, end up with an overbore, new rings, slugs, block deck etc, etc. Its that aircraft mechanic mentality i guess.Times like this i wish i had a borescope.
 
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Skip the cam. As AJ pointed out that 318 is probably lucky to have 8:1 for a compression ratio, it’s more likely in the upper 7’s.

You don’t need a tensioner, just install a new timing chain. If the chain is worn a tensioner won’t solve it. If you want to keep using the 318 later just throw a double roller on it so you don’t have to think about it again.

You probably don’t need the headers, not going to do much for you. Dual exhaust with the stock manifolds will be fine.

A dual plane 4 barrel intake is the way you want to go, just a plain eddy performer or weiand or whatever you can get. An old streetmaster intake will work too, that’s what I have on the stock-ish 318 in my Challenger. It’s a single plane, but the runners are small enough it doesn’t kill the low end. A more modern dual plane would work better though.

Carb is probably easiest to make a 600, although really you could probably use a 500 for regular old street use. 600’s are easier to find though.

I put over 60k miles on the 318 in my Challenger. It was rebuilt by a previous owner but not run, I have no idea what it’s specs are. It’s an 84 block with the original 1972 heads for my car. I suspect it’s 100% stock, maybe an “rv” cam but probably not. I ditched the 2 barrel that was on it for the eddy streetmaster intake and a 600 eddy carb. Big improvement going to the 4 barrel, mostly tuning related. The stock 2 barrels are a pita to work with. I have headers on it, but I doubt they do much other than make it a little louder. The car was originally 2.76 geared, which worked fine. I upgraded to 3.23’s which gave it a little more acceleration but still managed the freeways well. It wasn’t a fast car by any means, but it was still fun to drive. And easier to drive in traffic and around town than the built up 340 in my Duster.
 
moparmat2000 said:
I have a slightly used cloyes double roller, was gonna use a tensioner on it.
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What is your expectation for the 318? You say a "gutless wonder". I say each one of us have a different opinion of what a gutless wonder is to us. So, what do you expect out of it? I don't understand why everyone believes this is a "roll over an die" situation. So, if the expectations are "real", then you may be pleasantly surprised.
 
moparmat2000 said:
I dunno, not so quick. Like my wifes minivan can beat it.
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Then I say you'll be happy. 318 blocks are nothing less than a 340 missing 22 cubes of bore. Yes, it's a lot, but not the end of the world. 318's giving the same heads, cam, intake, carb and exhaust as a factory 340 and you'd be hard-pressed by the seat of your pants to tell the difference. One time my brother and I put used 340 components on a 318. Used I said. Carb, intake, cam, heads. Ran a stock 727 tranny and converter. 3.21 gears. The car ran 14.40's at 96 mph. We did use headers. Now, look up times of factory 340 cars, tested by anyone. That car had a tight "1700" stall converter in it, not the high stall 340 converter. I think that car was just a good converter away from hitting high 13's. I will never understand the spit 318's take by Mopar lovers.
 
I'm not giving it spit. Its the trans ratios that are gonna screw it. But like i said, where i live its hard to find some of this stuff, like a close ratio 4 speed. I wont do a slushbox either. Not my thing.
 
Actually the 3.09 first gear in that 833 OD won't be bad for taking off, 3.09x3.73 = 11.5 for your starting gear. The drop off to second gear is lame because of the wide spread, but that's the worst one. Shift high. :D
 
The 318 is pretty torquey. No problem with your 833-od
 
moparmat2000 said:
I'm not giving it spit. Its the trans ratios that are gonna screw it. But like i said, where i live its hard to find some of this stuff, like a close ratio 4 speed. I wont do a slushbox either. Not my thing.
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I didn't mean you in particular. :) We've owned a couple of 3 speed OD with 318's, they do better than you might think. And ours had 2.76's if I remember correctly. Yes, if you are at a low rpm in 2nd gear, not impressive. Scream 1st gear and slam into 2nd, it'll keep at it like nobody's business
 
Hang on,
I only mentioned headers cuz, I assumed you were gonna run them on the stroker. You're not gonna run 340 manifolds on the stroker are you? I don't see the logic in that.
In a stroker, you're gonna run something like a 284 cam, and with that od trans, a wide LSA, So maybe a 284/112. This cam, depending on the grind, would have 60* or more of overlap. Overlap can be like a supercharger with good working headers. That 284 wants headers. Without them the overlap period will not contribute much to the output of the engine. Of course a 408 would probably not miss the top end power cuz , well, it's a 408,lol.And you can only wind it up now and then on account of,well, speed-limits sorta get in the way.
But suppose you run a 268/110 in that stroker to make monster torque. Well, this cam still has 52* of overlap, so it will like headers too! But with all the torque this combo is gonna make,and the 3.09 low, you can run 2.94s, and hit 60 mph at the top of first doing 6500 with 28s. So headers aren't gonna do squat on a combo like that, on account of you'll be spinning all the way.
So I kindof get what you're thinking.
 
I will be extrude honing the 340 manifolds, and yes that bottleneck will hurt HP a bit, but i want it appearing stock under the hood.
 
Comments inside the quote
Dartnut said:
Fascinating.
After reading all of this, what advantage would a bone stock teener with headers be with a 4 speed O/D? The stock cam is a 240/248/112 with 20* of overlap. And most of that,if not all, is at below a useful lift. So basically insignificant in terms of boosting power with headers. So the only advantage to using the headers would be to help evacuate the chambers, and possibly to get rid of the hot gasses just a bit better than logs. As to what trans is behind it, I see no connection to the headers in this instance.
What about a bone stock teener with a 2 barrel carb and headers? Again, 2bbl, or 4bbl, I don't see a connection to the headers. With the stock cam, I doubt there would be 15hp difference at WOT. Furthermore the power is not added every where. It might make 15 at 4500rpm, reducing with rpm such that at 4000 it might be 12, and 3500 it might be 9 and at 3000 it might be 6 and at 3000 it might be 3.
Or would stock exhaust manifolds be as good as headers at this power/flow/stock cam combination? I think it would with duals, especially with the good logs, PM Trebleg for HO logs
The point that i'm getting at was that back in the day, i had a '71 Demon with a '69 318 that was totally stock including 2 barrel and stock exhaust manifolds, cam etc.
It had a factory 3 speed floor shift standard tranny in it and an 8 3/4 with 3:23 gears.
And man, it was fun to drive!
Was it just the right combination, or was it just luck?
It was. The 69 is the last year of advertised 9.5/1 compression. If the trans was a 69, then it was an A745. The ratios were 3.02-1.76-1.00, so your starter gear was 9.75, perfect for that teener. Second was out there a bit tho. The splits are .58-.56. If you wind up that 9.5 teener it did pretty good, I remember those.
If you had the 8.75 then you probably had an A230 with the synchronized low gear that came out in 71, the ratios were a bit closer,IIRC. I don't recall second but I think first was 2.95.
Is this a combination that the O.P. should consider? I think the OP is after the od, so I'm thinking no.
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The bone-stock teener makes pretty good torque, and easily pulls 3.23s; with any trans. 'Course it does better with 4.10s...................... I've had just about every trans you can imagine behind a bone-stock 1973 low-compression teener, except an A500, and with just about every rear gear from 2.45 to 4.88.

You know,back in the 70s GM came out with a planetary overdrive add-on for their Saginaw 3-speed. It didn't take any time hardly to fit that to the Saginaw 4-gear. I have many times wished that Mopar would have followed suit for the A833. Man; A 5 speed Mopar wouldda catapulted the 64 Barracudas right into stardom, and spelled the kiss of death for the Mustang.
 
moparmat2000 said:
I will be extrude honing the 340 manifolds, and yes that bottleneck will hurt HP a bit, but i want it appearing stock under the hood.
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The 340 manifolds work pretty good. Extrude hone will make them work even better. I would like to see a dyno sheet with a before and after comparison.
 
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Well I'll throw my hat in the ring on this one. I don't know about all the technical Cam and stuff you want to do but I've done pretty much the same thing when I first got my car it came with a 318 and I just built everything up around it in anticipation for the Stroker. I cleaned it up resealed it the best I could like you are talking about put a nice timing chain on nothing expensive. I put it in the car and then started buying all the parts I wanted for the Stroker motor and putting them on. Of course I started with headers on the 318 then started experimenting with other parts. Then of course I had to have a dual quad tunnel ram for the new Striker cuz that's bad *** has anybody knows. Of course maybe not the fastest anymore but badass none the less. Of course all everybody out here was screaming up and down about how that's way too much carburation blah blah blah blah blah. I dropped a half a second in the quarter mile though so whatever on that. Eventually I had quite a few nice components on the 318 which eventually that had the blow up at the track the day I wouldn't take it out of 3rd gear till the end of the quarter mile and that put a knocking her finally.
So yes my suggestion would definitely be put the 318 together the cheapest way you can and you'd be surprised you could probably throw sand in it and it run just great but don't try that please. I just got done rebuilding another 318 for my wife just using like you're talking about old timing chain old water pump old fuel pump free carburetor and a intake manifold given to me by a friend. it runs better than the damn 318 that came with the car that I blew up. So the plan you're discussing and anyways is the same plan and route that I took and I love my Stroker and I had fun building a second 318 and making it run crazy good. So if I have some misspellings here I generally voice command and a lot of times my punctuation isn't all that great cuz I don't go back and proofread too much so I hope I haven't said nothing into this voice command that comes out sounding crazy.
So my last word on this is go for it and do it as cheap as possible and like you said save the money for the stroker but definitely put the 318 in and give it a good whooping you'd be surprised how much it'll take. My-2...
 
Going back to post #1, the Dakota bearing woks just fine. But as to not shortening the pilot; I don't think the pilot hole in the 74 crank will accept the full-length input, so yes you'll probably have to drill it.I would mock it up and see what's what.
I've seen lots of cut-off inputs,just saying.
 
Just thinking about this, it might be ok. I have the trans and bellhousing mocked up w the engine no clutch or flywheel, and the trans spins freely when in gear. I can only assume byvthia that the input shaft is not hitting anywhere inside the crank.
 
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moparmat2000 said:
Just thinking about this, it might be ok. I have the trans and bellhousing mocked up w the engine no clutch or flywheel, and the trans spins freely when in gear. I can only assume byvthia that the input shaft is not hitting anywhere inside the crank.
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That's the way; uh huh,uh huh.As long as it stays that way when heated up!

Don't forget to adjust the pilot hole in the bell, to put the trans centerline on the same centerline as the crank. Do this after the block and crank are finish-machined and are ready to mate
 
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