Looking for advice on '68 318

What should be my first move on the 318?

  • Chill out, find the issue and rebuild to spec.

    Votes: 5 71.4%
  • Get the '75 360 cylinder heads on there!

    Votes: 0 0.0%
  • Balls to the wall on the rebuilt 360 install

    Votes: 2 28.6%
  • None of the above

    Votes: 0 0.0%

  • Total voters
    7

Jeff Porcaro

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Well I haven't posted much since introduction, but I haven't truly had a chance to dive into the 68 Fury quite yet. I've mostly been removing pounds of Canadian farm and dealing with rust here and there. I'm currently waiting on some new hardlines to come in, then first order of business is full brake system rebuild, and go for a ride to see if putting some load on the engine clears anything up.

Keep in mind I'm a complete engine newbie here, but willing to learn and figure **** out. Any tips and thoughts appreciated. Video below shows smoke and what she sounds like currently. It fires up just fine with a new battery, but smokes the entire time it runs even after it warms up. Idle isn't great, and there appears to be some ticking going on...




Now my first thoughts from what I've read is that it could be the valve seals or piston rings. I do have a certain itch to try and make more power from this 318, and have tried to understand what can be done from bolt on options such as aftermarket cylinder heads etc. What is the general consensus on a practical approach for rebuild here?

I currently am talking to a local guy who has some '75 360 cylinder heads that look damn near new that I can pick up @ $400 for the pair. It seems if I'm going through the trouble of valve seals, a whole cylinder head swap for better performance isn't a hard sell? They show casting #3769974 for a 1975-1976, 360 LA-series small-block with 1.88/1.60 valves

Again, total newbie as to what this entails in relation to the pistons or compression ratio change. Looking for sound input to help guide me through all the youtube and internet fog lol

there's also a local guy selling a freshly built 360 soup to nuts that looks beaut for $3500 that is tempting...please stop me
 
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I’m guessing if smoking is blue would be worn rings. My 68 Charger 318 blew a cloud of smoke at start-up only and then would use oil but not noticable smoke at sustained hwy speeds.
In the long run that rebuilt 360, especially if he’ll warranty it, might be best.
 
I’m guessing if smoking is blue would be worn rings. My 68 Charger 318 blew a cloud of smoke at start-up only and then would use oil but not noticable smoke at sustained hwy speeds.
In the long run that rebuilt 360, especially if he’ll warranty it, might be best.


I was worried someone was gonna say that lol
 
All I see is a little smoke coming from under the car. Is it coming out of the tailpipe? Or just under the car?

Frankly, it could be anything.... So a number of questions should be asked.

First, what color is the smoke? Blue means oil. Is it worse when it first starts?

Does the engine use oil? At what rate? Does it use coolant? (white smoke)

Have you done a compression test? That is what you need to do before you start going off and crazily spending money. Low compression could mean bad rings. Squirt some oil in the cylinders and if the compression comes up, it's the rings.

Smoke just from under the car (which is what I see) is usually a leak onto the hot exhaust.

These are just a FEW questions that need to be asked and answered first.
 
To me, your budget may or may not dictate your decision, but I voted for the 360 engine if you've got the money. Lord knows I've gone over budget with my build, but we ain't in this business to be economical.

Not sure there's any sense in throwing on new heads if you'll have to open up the block to begin with, but again, depends on what you want to spend. A rebuilt 318 with those 360 heads, depending on other parts, and if you're paying for labor, etc. will probably be less expensive than that 360 engine.
 
360 heads on a 318 will flow better, but you will drop the compression ratio by at least a full point due to the larger chamber size on the 360 head. You will probably be looking at a revised comp ratio of 7.8-8.0, not exactly ideal from a performance stand point. You would also want to source a 360 intake and exhaust manifolds to mate to the 360 ports on the heads. Most likely will also need to use the 360 push rods as well as the rocker push rod ratio is different on the 360. You will want to find out why the 318 is smoking to start with. Valve seals usually will cause oil consumption with smoke on start up but not after 30 seconds or so. Blue smoke all the time is usually the result of worn or broken oil rings, new heads won't help that. As noted, run a compression check and also run a hydrocarbon check on the coolant. If you have hydrocarbons in the coolant, there is a bad head gasket or a cracked head which could also be the cause of the engine smoking.

Dave
 
Usually, better to see what you've got before chunking lots of money into it, as a general rule. Get it running and driving reliably first and then drive it enough to get to know the car better. Learn about it and such, too. How many miles on it?

Doing the 360 swap might seem enticing, BUT find out what cam's in it first. Then what pistons and rings, so that an approx compression ratio can be determined. How much it was overbored during the rebuild, for general information.

The LA360 will require some additional things, especially if it's a 4bbl motor. Not just a straight drop-in situation.

According to an article on the 904 TFs in a '68 HOT ROD Magazine, they didn't take too well to drag racing, but with some friction and band upgrades (as in a rebuild), they could become very reliable and durable enough to handle drag racing activities. So, you might figure that into your ultimate upgrade costs, for general principles. But for normal drive-around activities, they were fine as is. Another reason to get things up and running reliably before spending any real money on the car OR even consider upgrades to the engine. In other words, spend as little on things as you can, once you get past what you've already got online for the brakes and such.

Remember that intake valve sizing relates to the size of the cylinder bore. For the rpm range the engine will generally operate in, what's there will be fine. Additional flow will only help at the higher rpms, usually. "Higher rpms" that would only happen with a 4bbl and such, rather than the smallish Carter BBD 2bbl the car probably now has. That extra flow will do little to get the car off the line quicker or with more wheelspin, but will make things feel better at the top of low gear. In other words, not in the normal driving speed ranges.

Do the normal tune-up stuff and get it optimized and running as good as it can. Also changing all of the rubber in the fuel system, tank to carb. At the tank, at the rear of the stubframe, at the fuel pump, and at the fuel filter. With a new fuel pump is one is not already there.

Just some thoughts,
CBODY67
 
All I see is a little smoke coming from under the car. Is it coming out of the tailpipe? Or just under the car?

Frankly, it could be anything.... So a number of questions should be asked.

First, what color is the smoke? Blue means oil. Is it worse when it first starts?

Does the engine use oil? At what rate? Does it use coolant? (white smoke)

Have you done a compression test? That is what you need to do before you start going off and crazily spending money. Low compression could mean bad rings. Squirt some oil in the cylinders and if the compression comes up, it's the rings.

Smoke just from under the car (which is what I see) is usually a leak onto the hot exhaust.

These are just a FEW questions that need to be asked and answered first.

Smoke is white to me. I should have mentioned that the smoke comes from under the center due to the exhaust tube being broken off right before the muffler. Smoking doesn’t seem to change much from start to warm up.

Very much appreciate the input and advice. Looks like a compression test is in the weekend plans - my buddy from work (owned his own auto shop in past life) has a compression tester he’s going to bring in for me tomorrow.

I just brought it down from AB Canada 3 weeks ago, and with work lately I haven’t had a chance to start it more than a handful of times for 10 minutes or so. Trying to soak up as much knowledge as possible before doing anything rash ($$$)
 
To me, your budget may or may not dictate your decision, but I voted for the 360 engine if you've got the money. Lord knows I've gone over budget with my build, but we ain't in this business to be economical.

Not sure there's any sense in throwing on new heads if you'll have to open up the block to begin with, but again, depends on what you want to spend. A rebuilt 318 with those 360 heads, depending on other parts, and if you're paying for labor, etc. will probably be less expensive than that 360 engine.


Hey...I can always appreciate someone trying to push me to do something irresponsible**cough** I mean friggen rad.

since there’s a good deal of family history and sentimental value in this car for me, spending money on it isn’t as much of a pain point as usual...especially if it means there’s a better chance my future kids can drive this car too!
 
360 heads on a 318 will flow better, but you will drop the compression ratio by at least a full point due to the larger chamber size on the 360 head. You will probably be looking at a revised comp ratio of 7.8-8.0, not exactly ideal from a performance stand point. You would also want to source a 360 intake and exhaust manifolds to mate to the 360 ports on the heads. Most likely will also need to use the 360 push rods as well as the rocker push rod ratio is different on the 360. You will want to find out why the 318 is smoking to start with. Valve seals usually will cause oil consumption with smoke on start up but not after 30 seconds or so. Blue smoke all the time is usually the result of worn or broken oil rings, new heads won't help that. As noted, run a compression check and also run a hydrocarbon check on the coolant. If you have hydrocarbons in the coolant, there is a bad head gasket or a cracked head which could also be the cause of the engine smoking.

Dave

I figured there had to be about a dozen other things I wasn’t considering with the 360 heads...

the more I hear from you guys the more I’m starting to chill and plan on starting with basics.
 
Usually, better to see what you've got before chunking lots of money into it, as a general rule. Get it running and driving reliably first and then drive it enough to get to know the car better. Learn about it and such, too. How many miles on it?

Doing the 360 swap might seem enticing, BUT find out what cam's in it first. Then what pistons and rings, so that an approx compression ratio can be determined. How much it was overbored during the rebuild, for general information.

The LA360 will require some additional things, especially if it's a 4bbl motor. Not just a straight drop-in situation.

According to an article on the 904 TFs in a '68 HOT ROD Magazine, they didn't take too well to drag racing, but with some friction and band upgrades (as in a rebuild), they could become very reliable and durable enough to handle drag racing activities. So, you might figure that into your ultimate upgrade costs, for general principles. But for normal drive-around activities, they were fine as is. Another reason to get things up and running reliably before spending any real money on the car OR even consider upgrades to the engine. In other words, spend as little on things as you can, once you get past what you've already got online for the brakes and such.

Remember that intake valve sizing relates to the size of the cylinder bore. For the rpm range the engine will generally operate in, what's there will be fine. Additional flow will only help at the higher rpms, usually. "Higher rpms" that would only happen with a 4bbl and such, rather than the smallish Carter BBD 2bbl the car probably now has. That extra flow will do little to get the car off the line quicker or with more wheelspin, but will make things feel better at the top of low gear. In other words, not in the normal driving speed ranges.

Do the normal tune-up stuff and get it optimized and running as good as it can. Also changing all of the rubber in the fuel system, tank to carb. At the tank, at the rear of the stubframe, at the fuel pump, and at the fuel filter. With a new fuel pump is one is not already there.

Just some thoughts,
CBODY67

Seems to sum it up pretty well. Mileage is unknown - it shows 9,601 right now but nobody believes it.

thanks for the input. I definitely want to make sure all fuel bits are up to snuff. Any recs on where to find good parts?
 
Smoke is white to me.

White smoke is usually coolant. Bad head gasket or other issues. Does it smell sweet like anti freeze? Or does it burn your eyes? That could be the carb running rich (stuck choke, leaking carb etc.)

Compression check may tell you if it's a head gasket. Do the Hydrocarbon test in coolant too.
 
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Do a leak down test also.You can get iron heads for a 318 for practically free...then get them redone if yours aren't any good.I wouldn't touch a 360 with a ten foot pole.
 
I have done the 318 to 360 swap. It was pretty much plug and play except the 360 uses a 360 specific torque converter as the 360 is externally balanced.
The 904 tranny should be fine.
 
UPDATE - I have not had a chance to pick up the compression tester from my buddy, but that is the next step. I did have a chance to do a hydro carbon test, and fluid never turned yellow no matter how long I kept pumping air from radiator. I'm taking this as a good sign for now?

I'm beginning to get more convinced that an "Italian tune-up" might be all that is needed to clear up this smoke. I'll drop another video I just took below - I only noticed it here and there on this start up. Will update again after compression test, and hopefully leak down test.

 
One other thing to consider, the driver side engine mount isolator is different between the 273 - 318 and the 340 - 360, as well as the balance issues
My $.02
 
UPDATE 2

Finally got a chance to grab a compression tester from my buddy and get to it today.

I'll drop photos below, but all cylinders were within 10-15 psi. Numbers ranged from 110-125 on the "dry" test. "Wet" test ranged from 115-130, averaging a ~5 psi increase on each cylinder.

The plugs were noticeably dirty, with only 1 looking not too bad. Its a wonder it ran as well as it did with these things. Ended up driving to Autozone to get some new plugs, didn't feel right putting these back into the engine knowing little bits were falling off.
IMG_2717.jpg


After replacing the plugs and hooking everything back up, she fired up a bit smokey from the wet test but then smoothed out to a nicer idle than I've ever heard it have. Hardly any shakey-ness at all now as well. Did a few laps around the neighborhood and it's hardly putting out any smoke...or at least an acceptable amount. My neighbors must have loved me today cruising around with no muffler!

I also just received some near mint hub caps from member Mike Parker and man are they beautiful. The challenge is now to make the rest of the car match!


 
Another fun item to add to the mix - I just noticed after another drive through the neighborhood tonight with my gf (gotta show off the progress!) that the fuel gauge and temp gauge are now pinned to max - Any idea what I could have done running comp test and changing plugs?

Gauges were reading fine before (and I think right after...?) the test...

EDIT: Also realized the panel light is no longer working, which was also working previously. Can the two occurrences be connected?
 
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