Last ditch effort for used 318

[SLOPAR72]

lot to be said for a good old vacuum gauge. Like a doctors stethoscope, tells you whats up, like it or not.

This right here.... After that leak it down..... Then after that compression check each cylinder and note the high number and amount of rotations and how many rotations to get to around 120.

I have done this enough times in my life now to realize that you gotta start with the basics and go from there...

JW

 

[mycuda]

Hi,

One rotation to 120PSI in those cylinders.

Vacuum at idle 12, fluttering a bit.

Doesn't burn oil, doesn't use oil, spark plugs no oil, all the same, normal light brown burn.

Thanks

 

[Infecteddog]

I think some of those 318 cop motors may have had as low as 7.5:1. comp. Dodges way of lowering NOX emmisions...

I think if you put think gaskets on the pre-'85 motors they can get that bad with larger chamber heads. I believe stock as low as they got was 7.8, and for 318s I think it was really 8.0. Keep in mind that they only had like 8.4:1 in the 2bbl small chamber motors. Bumping the compression to be somewhere in the mid 8s would be safe with the smallest of cams and help. The small cam smog 318s and 360s are not impressive but they will still run and pull through properly without good compression- it's very obvious to tell if it does right or not, should act just like a stronger motor pulling hard only without the actual power production. With a 340ish cam it really shouldn't be awful.

 

[nm9stheham]

If you are unlucky enough to end up with the truck 318 pistons, with a comp height of 1.658", then the tops are .163" in the hole...whoa! SCR works out to 7.22 even with .022 " shim head gaskets and 68 cc chambers! Otherwise, yes, you are up around 8 SCR + or - depending on chamber volume.

 

[AJ/FormS]

Hi,

One rotation to 120PSI in those cylinders.

Vacuum at idle 12, fluttering a bit.

Doesn't burn oil, doesn't use oil, spark plugs no oil, all the same, normal light brown burn.

Thanks

If this means that during the compression test, on the first compression cycle, she made 120 psi, then that would be absolutely fantastic!......Usually they don't make 80 or maybe 90 on the first shot.
Now , does that also mean that, after 4 or 5 or 6 compression cycles, it never made any more psi after that?
I'm not trying to be a dick, but a compression test is usually not finished, until the maximum psi is established,whether it takes 4 or 6 or however many compression cycles; and is best done with the carb at WOT, and the engine warm, or at least at room temp.

 

[mycuda]

Ive got it apart now, should get Timing chain kit tomorrow.

Are those chain tensioners worth a ****?




D

 

[SLOPAR72]

Hi,

One rotation to 120PSI in those cylinders.

Vacuum at idle 12, fluttering a bit.

Doesn't burn oil, doesn't use oil, spark plugs no oil, all the same, normal light brown burn.

Thanks

That 120 on your first rotation is actually good. How about the other 7? And that is not a good Vacuum signal based off of the info I have read but when I get a chance later I will review....

My guess is that thing is crazy lazy and feels like a truck load of sand it hooked to it....

JW

 

[SLOPAR72]

If this means that during the compression test, on the first compression cycle, she made 120 psi, then that would be absolutely fantastic!......Usually they don't make 80 or maybe 90 on the first shot.
Now , does that also mean that, after 4 or 5 or 6 compression cycles, it never made any more psi after that?
I'm not trying to be a dick, but a compression test is usually not finished, until the maximum psi is established,whether it takes 4 or 6 or however many compression cycles; and is best done with the carb at WOT, and the engine warm, or at least at room temp.

If all Cylinders hit the 120 that quick I would bet a hot dog a leakdown will probably show pretty good. I like the high number too but the initial number generally tells me if the motor is sealed up within reason.

I like that the input here is pretty good and the OP is headstrong to resolve the problem.... Kinda rare these days...

JW

 

[joec]

One of the problems is if the cam was ground 2 or more degrees retarded 4 degrees adv will help but wont put you at 106 icl. Sometimes you have to advance cam gear 1 tooth and put the crank gear 4 deg retarded to get to 106 or 102 icl.T think id try both ways with a comp test after each before buttoning up to see which gives more cranking comp.I just think cyl pressure is going to help with the laziness.With that cam in a low comp 318 I wouldnt expect a lot of vacuum.

 

[mycuda]

I will turn over and test compression after 4* cam advance thru crank gear.
I hope to see increase.

D

 

[SLOPAR72]

One of the problems is if the cam was ground 2 or more degrees retarded 4 degrees adv will help but wont put you at 106 icl. Sometimes you have to advance cam gear 1 tooth and put the crank gear 4 deg retarded to get to 106 or 102 icl.T think id try both ways with a comp test after each before buttoning up to see which gives more cranking comp.I just think cyl pressure is going to help with the laziness.With that cam in a low comp 318 I wouldnt expect a lot of vacuum.

I was expecting a minimum of 15......

JW

 

[needsaresto]

So a set of really thin head gaskets would be a cheap option that will help the op!

 

[nm9stheham]

Are those chain tensioners worth a ****?

Define '****'.... LOL. If this is an engine upgrade to get it to run well enough to sell, I would not bother.

 

[joec]

If it were 4 deg. ret. and you need to put it at 104 thats 10 deg adv. 14 to 15 adv. per tooth minus 4 deg. puts you at 103-104 icl.

 

[67Dart273]

If it were 4 deg. ret. and you need to put it at 104 thats 10 deg adv. 14 to 15 adv. per tooth minus 4 deg. puts you at 103-104 icl.

Which is why you need to stop screwing around and get a degree wheel and degree the thing "so you know." There are lots and lots of videos on the net about how to do so.

 

[toolmanmike]

Which is why you need to stop screwing around and get a degree wheel and degree the thing "so you know." There are lots and lots of videos on the net about how to do so.[/QUOTE

Agreed!

 

[SLOPAR72]

Which is why you need to stop screwing around and get a degree wheel and degree the thing "so you know." There are lots and lots of videos on the net about how to do so.[/QUOTE

Agreed!

Yes, you really do..... It also gives you the opportunity to degree your Harmonic.... The tools are not that much and if you will be doing things like this in your life suck it up and buy the tools...

JW

 

[dano]

The cam isn't the only thing that can be off. The crank key way, the two chain gears, the chain, distance between the cam tunnel and the crank, and the keys themselves.

A degree wheel and cam card is all that is needed to get it right and know its right.

 

[sireland67]

Hi,

One rotation to 120PSI in those cylinders.

Vacuum at idle 12, fluttering a bit.

Doesn't burn oil, doesn't use oil, spark plugs no oil, all the same, normal light brown burn.

Thanks

Here is an excellent vac gauge chart, I printed it off years ago and it is on the wall of my garage.

http://www.earlycuda.org/tech/vacuum2.htm

 

[joec]

Any progress?

 

[mycuda]

Cam was retarded a few degrees mostly because of cheap single chain stretch.
Advanced cam 4 degrees. Mancini double roller kit. I can feel the difference turning engine by hand, little harder to turn.

Assembling some today, finish accessories tomorrow, change oil and see how it runs.

Will update.

Thanks

 

[toolmanmike]

Cam was retarded a few degrees mostly because of cheap single chain stretch.
Advanced cam 4 degrees. Mancini double roller kit. I can feel the difference turning engine by hand, little harder to turn.

Assembling some today, finish accessories tomorrow, change oil and see how it runs.

Will update.

Thanks

We hope she's a screamer!

 

[mycuda]

Got it running, no leaks!
However some stupid reason WP pulley is hitting crank pulley?
Had to shim pulleys to line up.
Seems like damper didnt go on as far as it did? double crank gear?
Not to worried about that, not leaking oil, I can remedy.
17lbs vacuum at 800 rpm idle. Good sign up from 12.
Have 12* initial timing seems like advancing further than before upon hand working throttle.

Will take for ride tomorrow and see low end power results compared to before.

Will report back.


Thanks

 

[nm9stheham]

Hmmmm, did the crank sprocket pull for sure all the way up to the shoulder on the front of the crankshaft? Sometimes the crank keys can hang up pretty hard on the key slot on the sprocket and make it hard for the sprocket to go on all the way.

Or, maybe the outer ring on the damper got pulled out some, and is not letting the crank pulley seat in all the way...??

So the vacuum went up with nothing being done to the intake? That is certainly a bunch....

Will be waiting on the 'seat-of pants' results!

 

[joec]

Is the 12 adv. with vacuum connected ? It should probably be around 14 w/o vacuum connected . Also which vacuum ported or manifold? It should be manifold.Set it w/o vacuum hooked up then connect it to manifold vacuum(vacuum at idle).