Troubles with car

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Rodsaknockin

Rodsaknockin

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finally after many years of saving and working I bought a 1972 Dodge Dart swinger 318 car pretty well all original
Anyway I put dual exhaust on and tuned the 2 barrel carb ran great. Anyway the timing chain set failed and it did this when I went to restart it. so I ordered a 340 camshaft,eddy intake and a 500 cfm eddy carb and a double roller timing set put it all together and it is doggy out of the hole. Just doesn't have the same pep as before . I checked my valve spring height as well as compression. I'm sure it is a tuning issue but I can't put my finger on it .Checked my timing set it at 10 degrees. now when I shut the car off and leave it sit it floods it idles well and I set the air fuel mixtures with a tach and vacuum gauge. Run nice down the highway pull ok not as good as I would like. New to forums so if I'm in the wrong place please let me know. Any help or insight would be great thanks
 
You said the timing chain failed. Is it possible that you bent some valves? Also, you checked the valve spring height but did you get new valve springs to match the cam? As far as flooding when it sits...my guess would be an incorrect float/fuel level.
 
I checked the float level it is where spec says the compression is even so no bent valves and the cam only has a little more lift and duration machine shop said valve springs would be good for the cam I installed I will pull carb again and recheck float level thanks
 
In most cases, 10 degree initial NOT enough timing. Search "timing" in small block section.
 
And did you install the Cam straight up or Degree it in?
 
The quick answer is that cam needs more compression,a lot more.
But it's in there now so your best solution is a hi-stall TC, say about a 3200. Unless you have 3.55 gears or better, then a 2800 at the very minimum.
Here's the long version
>First the teener with the stock spec 240/248/112 cam
Static compression ratio of 8:1.
Effective stroke is 2.82 inches.
Your dynamic compression ratio is 6.95:1 .
Your dynamic cranking pressure is 132.97 PSI.
V/P (Volume to Pressure Index) is 108..............................................108VP

And then the stock teener with the factory 268/276/114 cam
Static compression ratio of 8:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 6.43:1 .
Your dynamic cranking pressure is 119.91 PSI.
V/P (Volume to Pressure Index) is 89....................................................89VP

Notice the VP numbers. These indicate or help us to understand why the lack of compression turned your teener into a dog. Notice how your engine has no only 89/108=82% of it's former stunning performance. That means the bottom end has lost 18% . You can think of this as having directly lost 18% of its former torque. Or you can think of it like going down to 82% in the rear gear ratio, say from 2.76 to 2.26; yeah that's doggy all right. Or from 3.55 to 2.91s
Notice also that your cranking compression is down to 90% of it's former number, and notice that your Dcr has fallen to 92.5% of it's former already very low number.

The proper solution to this is to pump up the static compression ratio. With iron heads and open chambers,(no quench to speak of) You can bump it up until the Dcr hits about 8.0:1
So crunching the numbers, I get
Static compression ratio of 10:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 7.98:1 .
Your dynamic cranking pressure is 159.36 PSI.
V/P (Volume to Pressure Index) is 119............................................119VP

See now yer talking! The factory teener came in at 108VP, and with an .030 overebore and with the above specs, you have now gained VP to the tune of 119/108=plus10.2% And a whopping 119/89=plus 33.7% more than your current set-up.

If you put some closed chamber Magnums on there, you'll lose 9cc of total chamber volume, but when you swap out that .020 steel factory head gasket, for an .028 , you'll gain back about 2.4 for a net loss of 6.6cc, and your Scr will jump from 8.0 to about 8.5, so it still sucks. So that by itself is not a viable solution.
No, the proper solution is to get the pistons up to the top of the deck AND get you some Magnum heads. Then you are approaching 10/1 and getting the Quench the engine needs and you can boost the Dcr up a lil more, say to 8.2
And that will look like this
Static compression ratio of 10.3:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 8.21:1 .
Your dynamic cranking pressure is 165.35 PSI.
V/P (Volume to Pressure Index) is 124..............................................124VP
And that will then be a total boost from the factory teener of 124/108=plus 14.8%, and a boost from the current combo of 124/89=plus 39%
This is at the Dcr limit for pumpgas and tight Q of .035 to .045 or thereabouts, so it can't get any better than this.

Hey, I made this mistake once too, so I know exactly what you're going thru. There is no tuning this away.
So the answer is; hi-stall or compression. Or for a real boost,both!

To run 8 to 8.2 Dcr with iron heads is gonna cost you premium gas most of the time. With open chamber heads, better make it all the time until you get a good tune into it.
Of course the cheapest answer is to pull that 268cam outta there,lol.

And if you don't boost up the compression, this combo will suck gas big time, but you have probably already discovered that,lol.And there is a threefold reason for that. With the cam in at 110, there are only 104* of power extraction, compared to the factory's 120* when in at 108*. And the second more important reason is the lack of heat in the combustion chamber. With the current combo's 120 psi of cylinder pressure, engine efficiency is way down; she is just not making any heat at cruise rpm. And the third part is; because of the low efficiency, you will have to use more throttle than normal to achieve your cruise rpm.
And if you plug in a 3200TC well forget about measuring fuel-mileage.

And now for a real eye-opener
Static compression ratio of 9.25:1.
Effective stroke is 2.82 inches.
Your dynamic compression ratio is 8.02:1 .
Your dynamic cranking pressure is 160.40 PSI.
V/P (Volume to Pressure Index) is 132...............................................132VP
Here is your factory teener with the 240/112 cam and the Scr boosted up to where the factory shouldda put it. Now that's a tire-fryer! And she's something you will be able to drive for hours and hours and hours on a single tank of gas.
If you put 4.30s behind this and a 2800, you can hit about 60 mph at the top of second gear, and be about the quickest thing around, to 60.
But more likely you'll like this with 3.23s, as a nice cruiser. 132/108 =plus 22% over stock, bottom end, which tapers off as the Rs rise,and so the advantage diminishes as the Rs climb to about peak-torque or somewhere around 3200/30mph in first for this combo.

And just for comparison, heres what a factory 360 looks like
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

And one more; If you advanced this cam with a 106* install, it could look like this
Static compression ratio of 8.0:1.
Effective stroke is 2.66 inches.
Your dynamic compression ratio is 6.62:1 .
Your dynamic cranking pressure is 124.66 PSI.
V/P (Volume to Pressure Index) is 96........................................................96VP
Better than a poke in the eye but still way down from the factory teener, and now sux gas even worse.

Read about VP here
Cam Timing vs. Compression Analysis

And here's a 1969 225cid with the factory 236/240 cam
Static compression ratio of 8.4:1.
Effective stroke is 3.58 inches.
Your dynamic compression ratio is 7.42:1 .
Your dynamic cranking pressure is 144.92 PSI.
V/P (Volume to Pressure Index) is 85.....................................................85

So your current 89VP is just 89/85=plus 4.7% stronger than good-running 225 from 1969. BTW; you should be able to run 87 gas in that current engine. lol.
 
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AJ/FormS said:
The quick answer is that cam needs more compression,a lot more.
But it's in there now so your best solution is a hi-stall TC, say about a 3200. Unless you have 3.55 gears or better, then a 2800 at the very minimum.
Here's the long version
>First the teener with the stock spec 240/248/112 cam
Static compression ratio of 8:1.
Effective stroke is 2.82 inches.
Your dynamic compression ratio is 6.95:1 .
Your dynamic cranking pressure is 132.97 PSI.
V/P (Volume to Pressure Index) is 108..............................................108VP

And then the stock teener with the factory 268/276/114 cam
Static compression ratio of 8:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 6.43:1 .
Your dynamic cranking pressure is 119.91 PSI.
V/P (Volume to Pressure Index) is 89....................................................89VP

Notice the VP numbers. These indicate or help us to understand why the lack of compression turned your teener into a dog. Notice how your engine has no only 89/108=82% of it's former stunning performance. That means the bottom end has lost 18% . You can think of this as having directly lost 18% of its former torque. Or you can think of it like going down to 82% in the rear gear ratio, say from 2.76 to 2.26; yeah that's doggy all right. Or from 3.55 to 2.91s
Notice also that your cranking compression is down to 90% of it's former number, and notice that your Dcr has fallen to 92.5% of it's former already very low number.

The proper solution to this is to pump up the static compression ratio. With iron heads and open chambers,(no quench to speak of) You can bump it up until the Dcr hits about 8.0:1
So crunching the numbers, I get
Static compression ratio of 10:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 7.98:1 .
Your dynamic cranking pressure is 159.36 PSI.
V/P (Volume to Pressure Index) is 119............................................119VP

See now yer talking! The factory teener came in at 108VP, and with an .030 overebore and with the above specs, you have now gained VP to the tune of 119/108=plus10.2% And a whopping 119/89=plus 33.7% more than your current set-up.

If you put some closed chamber Magnums on there, you'll lose 9cc of total chamber volume, but when you swap out that .020 steel factory head gasket, for an .028 , you'll gain back about 2.4 for a net loss of 6.6cc, and your Scr will jump from 8.0 to about 8.5, so it still sucks. So that by itself is not a viable solution.
No, the proper solution is to get the pistons up to the top of the deck AND get you some Magnum heads. Then you are approaching 10/1 and getting the Quench the engine needs and you can boost the Dcr up a lil more, say to 8.2
And that will look like this
Static compression ratio of 10.3:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 8.21:1 .
Your dynamic cranking pressure is 165.35 PSI.
V/P (Volume to Pressure Index) is 124..............................................124VP
And that will then be a total boost from the factory teener of 124/108=plus 14.8%, and a boost from the current combo of 124/89=plus 39%
This is at the Dcr limit for pumpgas and tight Q of .035 to .045 or thereabouts, so it can't get any better than this.

Hey, I made this mistake once too, so I know exactly what you're going thru. There is no tuning this away.
So the answer is; hi-stall or compression. Or for a real boost,both!

To run 8 to 8.2 Dcr with iron heads is gonna cost you premium gas most of the time. With open chamber heads, better make it all the time until you get a good tune into it.
Of course the cheapest answer is to pull that 268cam outta there,lol.

And if you don't boost up the compression, this combo will suck gas big time, but you have probably already discovered that,lol.And there is a threefold reason for that. With the cam in at 110, there are only 104* of power extraction, compared to the factory's 120* when in at 108*. And the second more important reason is the lack of heat in the combustion chamber. With the current combo's 120 psi of cylinder pressure, engine efficiency is way down; she is just not making any heat at cruise rpm. And the third part is; because of the low efficiency, you will have to use more throttle than normal to achieve your cruise rpm.
And if you plug in a 3200TC well forget about measuring fuel-mileage.

And now for a real eye-opener
Static compression ratio of 9.25:1.
Effective stroke is 2.82 inches.
Your dynamic compression ratio is 8.02:1 .
Your dynamic cranking pressure is 160.40 PSI.
V/P (Volume to Pressure Index) is 132...............................................132VP
Here is your factory teener with the 240/112 cam and the Scr boosted up to where the factory shouldda put it. Now that's a tire-fryer! And she's something you will be able to drive for hours and hours and hours on a single tank of gas.
If you put 4.30s behind this and a 2800, you can hit about 60 mph at the top of second gear, and be about the quickest thing around, to 60.
But more likely you'll like this with 3.23s, as a nice cruiser. 132/108 =plus 22% over stock, bottom end, which tapers off as the Rs rise,and so the advantage diminishes as the Rs climb to about peak-torque or somewhere around 3200/30mph in first for this combo.

And just for comparison, heres what a factory 360 looks like
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

And one more; If you advanced this cam with a 106* install, it could look like this
Static compression ratio of 8.0:1.
Effective stroke is 2.66 inches.
Your dynamic compression ratio is 6.62:1 .
Your dynamic cranking pressure is 124.66 PSI.
V/P (Volume to Pressure Index) is 96........................................................96VP
Better than a poke in the eye but still way down from the factory teener, and now sux gas even worse.

Read about VP here
Cam Timing vs. Compression Analysis

And here's a 1969 225cid with the factory 236/240 cam
Static compression ratio of 8.4:1.
Effective stroke is 3.58 inches.
Your dynamic compression ratio is 7.42:1 .
Your dynamic cranking pressure is 144.92 PSI.
V/P (Volume to Pressure Index) is 85.....................................................85

So your current 89VP is just 89/85=plus 4.7% stronger than good-running 225 from 1969. BTW; you should be able to run 87 gas in that current engine. lol.
Click to expand...
Whoa that's a pile of info to take into consideration. Thanks for the info I do want to stick with the 318 maybe a stroker version haha. I guess I better go sweet talk the wife!
 
You know;t a stroker will solve a lotta problems. It is much ,much easier to build compression with a longer stroke.
But before you get carried away, KB makes a piston, the 167, that has a compression distance of 1.81.This gets the crown up to about -.012 from a 9.600 deck. So on a virgin deck and using an .028 gasket, you might get down to an .050 quench height with closed chamber heads. This would total about 15.9cc from the top of the gasket down. add in the 62cc for the head and you get about 78cc. And that will turn your 318 +.020 into a 9.45Scr, 321.7cid stormer. This is enough compression for
An ICA of 54*
Static compression ratio of 9.45:1.
Effective stroke is 2.78 inches.
Your dynamic compression ratio is 8.09:1 .
Your dynamic cranking pressure is 162.22 PSI.
V/P (Volume to Pressure Index) is 131..............................................131VP

This could be a 262/270/108 in at about 104, a very nice number for a 318 streeter. If you review post #7 you will see that this is about the same VP as a stock teener with the compression optimized. And it's more bottom end than a factory 360 2bbl, about 9.2% more. That 360 would need 3.55s to keep up to this combo with 3.23s, in the lower rpm ranges. That's how you build a strong bottom end without going crazy on the TC.
The 262 cam will powerpeak at perhaps 5000rpm and with an automatic, will want to be shifte at about 1200 to 1400rpm higher so say 6400. That's about perfect for a streeter. The torque peak will come in at about 3750 So if you gear it with 3.73s... 3750 will get you about 30mph in first,and you are ready to take on all comers. Yet it will cruise 30=about 2200 so sneaky-like.
The 262 cam in this 9.5ish engine will easily pull less gears with the stock 1750TC, which with the new-found torque, may pop up to around 1900(guessing). I mean the VP is jumping from 108 to 131, an increase of 21% over the factory teener, and an increase of 131/89= plus 47% over the current combo.

So to recap;
KB 167s,thin gaskets,Magnum heads or at least closed chamber heads, a custom 262 cam, and then the bolt-ons. I recommend of course the 3.73s and a 2800TC but these you can work out later.
 
But say you really wanted to keep that 268* cam, and it is new.....so;
Well an acquaintance of mine found a small-main 3.58 crank. All he did was jam that crank in there with the pistons that were in there,which of course popped up; 1/2 the stroke difference or .133. This popped the pistons up out of the hole. But with the .039 FelPros and open chamber 360 heads, there was room to accommodate that. The compression came out a little high so he took a little off the top of the teener slugs, leaving the Q-pad alone, Thus making a step-dome This also provided a little room for pv clearance.
I bet hundreds of guys have done this with those mid to late 70s teeners with the pistons way down in the holes.
Anyway I don't recall anything about the cam. But I do remember how hot that little 344 was.
I'm guessing the Scr was about 10.5 (I did a little math), and with a 268* in at 110 cam it looks like;
Static compression ratio of 10.5:1.
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.40:1 .
Your dynamic cranking pressure is 170.32 PSI.
V/P (Volume to Pressure Index) is 138...........................................................138VP
That's probably too much Dcr for even 91 gas, but get a load of the VP.

Dropping the Scr a bit, it looks like this
Static compression ratio of 10.1:1.
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.09:1 .
Your dynamic cranking pressure is 162.22 PSI.
V/P (Volume to Pressure Index) is 130 ...totally doable....................................130VP

Or retarding the cam to 114, and back at 10.5, I get
Static compression ratio of 10.5:1.
Effective stroke is 2.69 inches.
Your dynamic compression ratio is 8.14:1 .
Your dynamic cranking pressure is 163.52 PSI.
V/P (Volume to Pressure Index) is 127..........................................................127VP

So it looks like 127 to 130 is about as good as it can be with a 268* cam, which is really really good for a 318 with a big cam. OOps I mean 344 cuber,lol. This rivals the 132VP of the factory teener with the Scr boosted up to 9.25, but of course the top-end rush at 10.5 with the 268 will be phenomenal, for a 318/oops 344

But again, to reiterate, it's probably cheaper to just start with a 360

Sometimes just because it can be done, doesn't mean you should try it.
 
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You are absolutely in the right place; welcome!

'Doggy out of the hole' indicates 1 of 2 things:
1. Too much cam for what is already a low compression engine; I actually WOULD expect a drop in performance with the 340 cam at low RPM's; your 318 is low compression and a bigger cam will automatically drop what is called dynamic compression ratio, which is going to directly lower you low RPM torque. This is what AJ explained in hard numbers in his 2 paragraphs comparing the stock to 340 cam.
Making up for this with ignition advance may help to some degree as suggested in post #4 and you can go much more than 10 degrees. But you need to then limit total by working inside the distributor. All that is very doable.

2. Cam installed wrong, with the crank and cam sprockets not lined up right. Hard for us to say what was done here. Did you find the true TDC of cylinder 1 and check the crank damper mark and line up the sprockets with the engine set that way? If, not then it is time to first find true TDC and check your damper's timing mark.

With the mildly larger cam, you can fix some of this by re-installing the cam advanced, regardless of what else you do. I would not hesitate to advance it 6 degrees or even 8 degrees with that engine. (ICL around 104) That will raise your DCR and give you back some ow end torque.

Then, if budget limited, shave the heads .050" (about 8 cc less chamber volume) and use .028" head gaskets.

With the 2 above changes, and starting with AJ's DCR number of 6.43 with your stock engine and the 340 cam, I come up with an increase of DCR to 7.4, a jump of one whole point in DCR. That is pretty good for the money. You may have to shim up the rocker shafts by about .020" to make up for the milling, and should definitely mill the intake to match with that much head shaving.

The above is not the way to do a real performance 318 IMHO, but sometimes budgets are what they are, and you need to try to do what you can for what you have.
 
MRL bored a 318 to 4.00
Put a 3.58 crank into that and you have a 360.
And there are tons of pistons available for that.
And from the outside, it looks exactly like a 318, exactly.
Put any old top end on it and go play, including the 2bbl heads and the 2bbl cam,lol.
But
With the 268* in at 110;
Static compression ratio of 10:1.
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.01:1 .
Your dynamic cranking pressure is 160.14 PSI.
V/P (Volume to Pressure Index) is 135......................................................................135VP

Yes the 2bbl heads will choke the 268* cam but ask yourself............ when;
Top of first gear will still be spinning, so no problem there. And 65 mph with 2.76s is 3600rpm in second, so no problem there either.
Ok but what about 3.55s? Well 65=4640(2nd) so still no problem, we just reached peak-torque.
So what will it take to choke the 268*? Well the 268 normally would peak around 5200.So 5200 with 4.10s makes 63mph. So lets call 4.10 and 80" tires the choke point.
Now granted 2.02 bigports will pump up the midrange some, so the small heads will slow you down a bit in second gear, say beginning at 46 mph, with those 4.10s.
But more likely is you are gonna run 3.23s or 3.55s. So with 3.55s the slow-down begins at 53mph, and with 3.23s at 58.
So, a streeter on a budget, run whatever heads thatcha got, within the Dcr limits of the available gas.
I'll tell ya; VPs over 130 are pretty nice with small gears and small TCs .

But for brute strength, this is what I once ran,not too long ago; Eddie headed 360.
Static compression ratio of 10.9:1.
Effective stroke is 2.86 inches.
Your dynamic compression ratio is 8.91:1 .
Your dynamic cranking pressure is 183.76 PSI.
V/P (Volume to Pressure Index) is 162.........................insane low-end................................162
Some guys have run even higher numbers, but mine ran on 87E10

I currenty run this
Static compression ratio of 10.9:1.
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.72:1 .
Your dynamic cranking pressure is 178.73 PSI.
V/P (Volume to Pressure Index) is 153.............................much more sane...........................153
Still on 87E10

It's really fun to play with VPs
Say you get yours up to 130 and you run 4.10. If you multiply these two together you get 130x4.1=533.
And if you devide that by 3.55 you get 533/3.55=150 about the same as my current 153VP.
Now, I know exactly how monstrous my bottom end is even running 3.55s. So I have a pretty good idea how powerful your engine will feel with 130 and 4.10s.

Ok so let's try another; yours at 130x 3.55 x 2.45 x 1.1 in the TC =1244, this would compare to mine at 1244/153/2.66=3.06 rear gears, if I slipped it out as quick as I could, to simulate your TC.

And here is one for you to aspire to 153(my VP) x 3.55x3.09=1678 And divide that by 130(your recommended minimum VP) you get the starter gear you need to keep up with me; So1678/130= 12.91. So taking out the 1.1 in the TC we get 11.75 and dividing by the 2.45 low gear, we get the rear gear of 4.79s................
And that is why I have a 360,lol, (and also why I have a GVOD, cuz first-over maxes out at 68 mph or a bit more,lol; but that's another story)

Now, always remember that these VP numbers only help us understand and predict how a certain combo will perform at lower Rpms, and are especially useful to guys with M/Ts or low-stall TCs.
If you slam a 3500TC in there, the VP number means pretty much nothing to you.
But if you have a clutch, there will be many,many hours spent in the zone where the VP is,or can be, supremely important.
 
man, if you were not in Canada, Id give you a 360 crank that has been turned down to 318 mains and you could probably still use your old low comp 318 pistons with it and a thick head gasket....Just needs a weld. Maybe not.....
 
Real world test results trump math . Here's what happens when you pull a Comp 260 dur 440 lift cam out of a low compression 360 and replace it with a 318 cam. You lose power EVERYWHERE(well, maybe not below 2500 rpm). 40 hp loss at peak. No stock 318 cam for me, thanks. Let's put a mild 8.2:1 360 on the dyno.
 
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