Engine rebuild choices

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ArizonaKid

ArizonaKid

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Im building up a 318 for my dart, its not going to be high performance, but it will be above stock, and im looking for suggestions/answers for it.

I guess the first thing is, i will be using it for a daily motor, on city streets, the highways (everyday, and long distance up and down the west coast), towing a small camp trailer, and to be able to smoke a honda if the mood strikes me. :burnout:

I have a 318 from 1972 that came out of a 1966 charger. it had been sitting since the 80s with one owner, its a stock motor, with the two barrel intake and factory manifolds. I have a forged steel crank for it. I have a set of eagle headers that i am using for the motor, along with an edelbrock economy 4 barrel intake, and a thermoquad.

Right now i have a perfectly good running 225 slant in the car, so i can wait a long time before installing the motor. I work intermittently, so i cant get high priced parts, but i can save for important, quality parts.

I need a suggestion for pistons, for a good cam, lifters, a good header gasket and whatever else anybody can think of.

Heres one of my questions; what type of piston rings should i use, i've read that chrome rings are good for a dirty environment, but also that for my motor, iron rings would be best.

Thats my only question now, but i'll have more later.

I have built a couple motors before, but not one from a stock like this, so any help or suggestions will be appreciated.
 
Chrome rings are hard on the bores. You'll want moly rings if it's going to be bored/honed or cast rings if you're going to try and roll the dice w/o machining.
 
Most bang for the buck, go with a magnum motor (318 or 360, which kills me to say because I prefer the LA block over magnum). Or look into late 80s/early 90s la roller block and build one of those. The roller cam will bring you into the power curve sooner and keep you there longer than a flat tappet cam. Another thing to look at it (which you've stated) is towing. A 360 produces more torque than a 318, which isn't to say a 318 can't tow just a 360 can do it easier.
Just something to think about before you start buying parts.

From what it sounds like you want keep the stock stroke.
You're basically looking at some flat top pistons to bring up compression to about 9.5:1 (pump gas friendly) with the new piston rings. A four barrel intake like a performer intake from Edelbrock. A 650 cfm carb will do you just fine. A set of Doug's headers with a good flowing exhaust system (2.5" diameter will do you just fine). Heads a set of 302 heads ported and cleaned up will do you just fine or a set of RHS heads, either way gasket match the ports. A eletriconic ignition. A new oil pump (no real need for a high flow unit). 195 degree thermostat is what I'd run/use. Personally I fine the stock oil pan lacking and opted for the milodon road race oil pan for the fact that it sits above the k member and holds 6 quarts.

The cam, well that depends on other things like rear gear ratio, what tire size you plan to use/run, what kind of tranny auto (if auto what converter are you using and if need be are you willing to change the converter if need be) or manual (which one)?
 
First off, if a motor is "above stock" it is high performance. A stock engine can be high performance. Look at the 340. High performance refers to things other than dyno output, too. Things like the forged crank you mentioned you have. That's a good piece, and it's high performance, because it has greater durability and endurance than a standard cast crank.

Iron rings, for example, are not high performance. You will benefit best from a moly ring. Anytime you talk about rings, it refers to what the top ring is coated with. So when you say moly rings, the top rings have a moly coating. Or chrome rings the top ring has a chrome coating. If you ever hear someone say "I have chrome moly rings" they are full of crap, because there's no such thing. They are either plain iron, moly coated or chrome. IMO moly rings will suit you best.

If you're going to buy any pistons at all, you may as well buy some that will raise compression. There are plenty out there to choose from. I would keep compression at 9.3:1 at the absolute most. This seems to be kinda a magic number for non quench engines, which yours will likely be. Plenty of compression to make gobs of torque, but not so much where detonation is an issue. Expect to run premium gas though, if you want anything that resembles a performance timing curve.
 
80fbody said:
Chrome rings are hard on the bores. You'll want moly rings if it's going to be bored/honed or cast rings if you're going to try and roll the dice w/o machining.
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Thanks, i'll probably go with the cast rings in that case, the fact is i don't want to send it out for machining if i don't have to. If i do have to get it sent out, i will go with the moly rings.
 
1970Duster said:
Most bang for the buck, go with a magnum motor (318 or 360, which kills me to say because I prefer the LA block over magnum).
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The problem with that is, I have a perfectly good motor now, I dont want to spend the money to get a new motor, then have to recuperate that cost by selling a motor thats difficult to get any money for.

It would be better to have a magnum, but im simply not willing to go with that kind of cost and effort to buy and build one.

I do appreciate the input though, thanks.
 
RustyRatRod said:
If you're going to buy any pistons at all, you may as well buy some that will raise compression. There are plenty out there to choose from. I would keep compression at 9.3:1 at the absolute most. This seems to be kinda a magic number for non quench engines, which yours will likely be. Plenty of compression to make gobs of torque, but not so much where detonation is an issue. Expect to run premium gas though, if you want anything that resembles a performance timing curve.
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Alright, thats the kind of thing i was looking for, any suggestion on brand and type?
 
1970Duster said:
The cam, well that depends on other things like rear gear ratio, what tire size you plan to use/run, what kind of tranny auto (if auto what converter are you using and if need be are you willing to change the converter if need be) or manual (which one)?
Click to expand...

I didn't realize there was that much involved in choosing a cam, right now the car is a stock 225 slant six, i'm not sure of the gear ratio because the tag is gone, :eek:ops: and I don't remember what it was when i re-did the seal. The transmission is a stock A-904 automatic, nothing has been changed on that. if i needed to, i would be willing to change the converter, especially because the motor would already be out. my tire size would be 215/70/14's all around.
 
ArizonaKid said:
Alright, thats the kind of thing i was looking for, any suggestion on brand and type?
Click to expand...

I like the Speed Pro hyper pistons because they don't require the special file fit to the rings that the KB pistons do. Also for rings, lets clear something up. They are ALL cast. Saying "chrome" or "moly" simply means the coating applied to the top ring.

If you order cast rings, you are going to get a plain old non coated cast top ring, which you don't want. Plain rings haven't been used in the industry in a long time. They use moly rings in nearly everything now. This is probably one reason when you tear a modern engine down that there is still cross hatch in the cylinders.

While it's true, chrome rings are hard rings, as long as the cylinder is prepared properly, they won't be any harder on the engine than a moly ring. They just require a different finish on the cylinder wall. If the cylinders are not finished for chrome rings and you use them, that's when you can run into premature cylinder wear. Every internal combustion engine in airplanes uses chrome rings. I don't think prop planes would be flyin around with them if there was a problem.

The moly rings are more forgiving to things like cylinder imperfections. So, if you are going to do a basic re-ring, and simply hone the cylinders, moly rings are what you want. Moly rings are tough and hold up very well. Though they take a little longer time to seat because the moly coated face is harder than a standard non coated ring, their benefits far outweigh uncoated rings, IMO.

As to which brand ring, it really doesn't matter, because they are all made by probably only about three companies anyway and rebranded. What I always do is pick the cheapest moly ring and go with it. Don't look them up by application. You'll pay more. Go on the Summit site and look them up by specific bore size and by their width. The width will depend on which piston you choose. Just get the width the piston requires in the correct bore size and choose the "low to high" price option and get the cheapest ones. That's how I've done it for years and I always pay less than if I by for the make of engine. If it has Mopar attached, it's automatically more money.
 
ArizonaKid said:
I didn't realize there was that much involved in choosing a cam, right now the car is a stock 225 slant six, i'm not sure of the gear ratio because the tag is gone, :eek:ops: and I don't remember what it was when i re-did the seal. The transmission is a stock A-904 automatic, nothing has been changed on that. if i needed to, i would be willing to change the converter, especially because the motor would already be out. my tire size would be 215/70/14's all around.
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Jack the rear of the car up and support it with stands. Take a piece of chalk and mark the rear of the drive shaft. Mark one of the backing plates and mark the drum in line with your mark on the backing plate. Put the car in neutral. Have a friend hold the un marked wheel still. Turn the drive shaft one complete revolution from where you marked it. Note how many times the wheel turned that you marked. If the wheel turns 3.5 times to the drive shaft's one, you have a 3.55. If it turns a little more than 3 times, you have a 3.21 or a 3.23. Get the picture? Oh and if by chance you have a limited slip, your friend will not need to hold the other side. You will know because if he's holding it while you try to turn the drive shaft, you will not be able to turn it until he turns the tire loose.
 
ArizonaKid said:
I didn't realize there was that much involved in choosing a cam, right now the car is a stock 225 slant six, i'm not sure of the gear ratio because the tag is gone, :eek:ops: and I don't remember what it was when i re-did the seal. The transmission is a stock A-904 automatic, nothing has been changed on that. if i needed to, i would be willing to change the converter, especially because the motor would already be out. my tire size would be 215/70/14's all around.
Click to expand...

Houston, we have a problem. Plan on changing more than the converter. A slant trans won't bolt up to a V8. The bellhousings are totally different. The 2.76 geared 7 1/4" won't live long behind a stout V8 so plan on that swap down the road. If this were MY car here's what I would do. !. Set of Schumacher conversion mounts (www.engine-swaps.com) since I have a slant K member. 2. Find a V8 904 tranny with a stock converter. 3. Bolt the stock '72 engine/904 trans together and drop it in the car. 4. Drive the wheels off it until something breaks or the fun is gone and then reassess. Don't know why but '72 318s were magic. They were the stoutest stock 318 I ever ran across. Lord, did I have fun in Dad's '72 Swinger...
 
Transmission needs to be changed to put a 318 in a 6cylinder car.
 
grumpuscreature said:
Houston, we have a problem. Plan on changing more than the converter. A slant trans won't bolt up to a V8. The bellhousings are totally different. The 2.76 geared 7 1/4" won't live long behind a stout V8 so plan on that swap down the road. If this were MY car here's what I would do. !. Set of Schumacher conversion mounts (www.engine-swaps.com) since I have a slant K member. 2. Find a V8 904 tranny with a stock converter. 3. Bolt the stock '72 engine/904 trans together and drop it in the car. 4. Drive the wheels off it until something breaks or the fun is gone and then reassess. Don't know why but '72 318s were magic. They were the stoutest stock 318 I ever ran across. Lord, did I have fun in Dad's '72 Swinger...
Click to expand...

Oh my god, i cant believe i outright forgot. I knew i had to change the k member, but i completely forgot about the tranny, Im pretty sure I have one in the shed though.
 
grumpuscreature said:
Houston, we have a problem. Plan on changing more than the converter. A slant trans won't bolt up to a V8. The bellhousings are totally different. The 2.76 geared 7 1/4" won't live long behind a stout V8 so plan on that swap down the road. If this were MY car here's what I would do. !. Set of Schumacher conversion mounts (www.engine-swaps.com) since I have a slant K member. 2. Find a V8 904 tranny with a stock converter. 3. Bolt the stock '72 engine/904 trans together and drop it in the car. 4. Drive the wheels off it until something breaks or the fun is gone and then reassess. Don't know why but '72 318s were magic. They were the stoutest stock 318 I ever ran across. Lord, did I have fun in Dad's '72 Swinger...
Click to expand...

X2 I just refreshed a 318 and took the 360 heads and performance cam out { xe268 } in favour of the stock 318 heads and the cam that was in the motor before the " Willie Wanker upgrade " . I would suggest you ignore everything else and do what Grumpus suggests , only I would build to 60s spec not the 72 , the 2 bbl 318 was rated at 230 hp and 260 tq back in the day , you will love driving this combo over your current /6 while you save for the next step , stroker , 8 3/4 and a built trans .
 
9:1 CR, 600 cfm performer carb and intake, headers and an RV cam something like 256 .425 112 should put ya in mid/high 200's hp.
 
A couple thoughts...

If your 318 is running now, and you just want to freshen it up I would get a Speed-Pro overhaul kit. This will get you a complete gasket set, rings, main and rod bearings and maybe a timing set. Keep in mind you'll have some bucks into your heads. You WILL need 16 valve guides, a set of valve springs, locks and possibly some valves. The cost of your head work can be offset by selling the steel crank. You don't need it! It's worth more to you in somebody's 340. If the bores and current crank are serviceable, I'd keep running the pistons you have and spend the money elsewhere.

Edelbrock "economy" intake? I hope it's not an SP2P. A basic 2176 Performer or older LD4B would be much better.

If you don't have a transmission, I do. I've been saving a (core) 72 small block 904 to rebuild and sell. Currently I'm launching a lot of stuff I had been saving. Lemme know.

Cam wise, I'd keep it fairly mellow. You most likely have a 2.94 geared 7 1/4" rear now. Keeping with the low buck theme, let's assume you run a factory replacement "high stall" converter from Transtar downtown. Same converter as a 340 car, later 4 BBl small blocks, cop cars etc... 2000-2200 RPM stall. So why not just run a factory 340 replacement cam and valve springs? The price is right. Or, a Comp XE 260.

BTW ALL rings are cast iron, it's only the face coating that's different. A typical moly faced ring would be best. You will need to do at least a glaze-break hone no matter what.
 
C130 Chief said:
A couple thoughts...

If your 318 is running now, and you just want to freshen it up I would get a Speed-Pro overhaul kit. This will get you a complete gasket set, rings, main and rod bearings and maybe a timing set.
Cam wise, I'd keep it fairly mellow. You most likely have a 2.94 geared 7 1/4" rear now. Keeping with the low buck theme, let's assume you run a factory replacement "high stall" converter from Transtar downtown. Same converter as a 340 car, later 4 BBl small blocks, cop cars etc... 2000-2200 RPM stall. So why not just run a factory 340 replacement cam and valve springs? The price is right. Or, a Comp XE 260.
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Im not sure if the 318 will run right off, but it does look clean in the cylinders, the plugs are good too. The cooling system is sealed off, save for a missing freezeplug on the block. I already planned on getting a refresh kit if it wouldn't run straight off, but it would probably be better to get one either way.

The motor turns over freely, so it shouldn't (don't you love that word?) be too terribly difficult to start up. What years do you mean by later 4BBl small blocks? and would you trust a junkyard converter? Theres a jalopy jungle with plenty of dodge trucks with 318's for relatively good prices.

What brand would you recommend for a cam and lifters? I only ask because my father, after rebuilding our trucks motor, experienced a comp lifter failure, replaced them with another set of comp lifters, and one is failing again. After a high stress period (usually the freeway) the lifter wont pump back up and becomes very loud and annoying.
 
Check out Summit's K-6401 cam /lifter kit. (Usually ground by Crane or Mellings). The price is right(under 140.00 ,cam & lifters) Some new 340 style valve springs,would be a damn good idea. Used the grinds in Chevy & Ford budget builds,had good luck with both.
 
Hey Abodybomber, do you mean a k6901? i couldn't find a k6401 on summits site, I checked under 318, 340 and 360, and the same four kits came up for the three motors, under the summit brand.
 
ArizonaKid said:
Hey Abodybomber, do you mean a k6901? i couldn't find a k6401 on summits site, I checked under 318, 340 and 360, and the same four kits came up for the three motors, under the summit brand.
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I got that cam (k6901) in my truck's 360
nice lil rumble too it
 
I'm bad about keeping up on stuff and i'm sorry about that. I found a good cam, a mopar purple shaft.

http://www.jegs.com/i/Mopar-Performance/312/P4452761AE/10002/-1?parentProductId=746961

And unfortunately, I found some pretty bad pitting in three of the cylinders, so i'm forced to bore it out. The good thing about it is that I can get some better pistons in the process.

http://www.ebay.com/itm/161830585424?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

I decided to go with a flat top to bring my compression up a bit, as I decided that, since an overbore is required, better airflow would be a good thing. Luckily, my dad has some nice 360 J heads in the basement he's letting me have, I just have to get the hardened valve seats done. At least I don't have to buy new valves, but this is going to cost about $300 more than I originally thought.
 
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