Which way do i go? I want to retard it 4 degrees.

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The cam is in the engine now, so it's a done deal.
I can hardly wait for the results!

4 degrees represents about 10 psi cranking cylinder pressure.
If you only had 140 psi to start with, that would be a big deal. But if you already have 190 psi, an extra-10 could be too much, and 180 might be better.
But changing the cam timing does more than just change the CCP.
To get extra CCP, you gotta steal it from the Power-Stroke; AND it also changes the way that the Overlap-Lap cycle works.
For a streeter to sacrifice Power-stroke, means a reduction in efficient fuel usage in cruise-mode, which affects you cruise fuel economy. Coupled with the wrong rear gear, this can be a really big deal.
And if you mess with the overlap, and have headers, this can affect not only the absolute power-output, but the entire powerband. On the street this may not be a big deal. But again, this can and will affect your low-rpm and cruising fuel useage.

Regardless;
The cam is in the engine now, so it's a done deal.
I can hardly wait for the results!
That's more cam than I will ever run, but it's interesting none the less.
 
AJ/FormS said:
That is true, but car still went 93 in the Eighth, with the tach stuck on 7000 pretty much the whole way.
Click to expand...
We know. You say that in every thread. Ok not every thread but almost every thread. And it gets 32mpg US. We know. And it goes sideways every time you turn a corner. We know. And it runs 180psi on full timing on 87E10. WE KNOW!!
 
TT5.9mag said:
We know. You say that in every thread. Ok not every thread but almost every thread. And it gets 32mpg US. We know. And it goes sideways every time you turn a corner. We know. And it runs 180psi on full timing on 87E10. WE KNOW!!
Click to expand...
and it does all of that on 25yr old wires, cap, rotor, plugs and tires!

them BFG's must be made of magic to still be around after that kind of use!
 
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Clelan said:
This is in my street car.

Cley
Click to expand...
Like you said, it's an education that you pay for with just a gasket and some time... and "trial and error". i have played countless games like that. Had we had "internet" and "forums" back then, I'd been butchered like and Easter Ham
 

All I see on the gear is the 0 mark which is probably straight up and the triangle mark, I don’t see a third symbol and am wondering how you know if it is advanced or retarded it 4? Ie: is the triangle retarded or advanced? If you finitely knew which one the triangle is you can use the process of elimination to determine which is advanced or retarded…
 
4mulas said:
All I see on the gear is the 0 mark which is probably straight up and the triangle mark, I don’t see a third symbol and am wondering how you know if it is advanced or retarded it 4? Ie: is the triangle retarded or advanced? If you finitely knew which one the triangle is you can use the process of elimination to determine which is advanced or retarded…
Click to expand...

Or you can degree the cam after moving it.
 
Clelan said:
Man, this simple question is asked really went cow **** didn't it!

Cley
Click to expand...
I didn't think so. I think guys are trying to make sure you don't make a mistake you'll regret is all. I guess if that's your definition of ****, then so be it.
 
junkyardhero said:
and it does all of that on 25yr old wires, cap, rotor, plugs and tires!

them BFG's must be made of magic to still be around after that kind of use!
Click to expand...
I guess you missed the part about the car being on the 5th set of tires from 1999 to 2005 or so..
And about that coil; without a doubt, she is the toughest coil I ever installed, she even tolerated full batery voltage, from time to time.
----------------------------------------------------------------
To the OP:
The following is just for perusal.
From yr 2000 to 2004, I ran a 223@050 cam, and the car was geared 65= about 2000 in overdrive.
>At 11.3 Scr that cam made nearly 200psi, so it was a no-brainer to retard it for a lil less pressure, and for a lil more topend.
>For the gas-mileage run, that 223 cammed iteration was geared 65=1600.
>Eventually, about year 2004/or 2005, that 367 received a cam of 230@050, would be re-engineered at 10.9Scr, and would be geared 65=2240. Yes, I took the engine down, and installed a different trans.

>The keys to fuel economy as it pertains to the engine, that I discovered are;
Low rpm and plenty of ignition timing, combined with chamber shape, chamber material, Squish, modest overlap and a long power-extraction period. If you don't need the pressure, give some cam timing to the Power stroke, and
increase the exhaust period so you can move the overlap cycle back and forth without destroying the overlap triangle.
>With these things in mind, it is possible to have Both Power and Economy in the same modestly-cammed engine, but it will never happen with a 114 Lsa and lack of cylinder pressure; because the lobe-centerlines are just too far apart to be played with..
What happens is that you trade chit for chit and have chit for overlap.
>I mean look at the stock 318 cam; 240/248/112
In at 110, it has a centered overlap, a compression stroke of 130 degrees, and a powerstroke of 122*. These are insanely huge numbers.
At 8/1 Scr, the pressure is likely to be ~136psi. This engine makes fuel economy NOT by pressure, but by the long Powerstroke which offers lots of time for the fuel charge to finish burning in the chamber; and the near miniscule overlap doesn't waste any fuel on the overlap cycle.
> Now;
you take that cam out, and install a 340 cam; 268/276/114, in at 112 to center the overlap, and the Compression degrees drops to 114, and the powerstroke to 106*. In the same 8/1 engine;
CCP drops to ~117psi, and the bottom-end goes away.
but the 106 Powerstroke seals the deal for lousy fuel economy compared to 122 of the stock cam; and since you put headers on it now, even the modest 44* of overlap is sending raw fuel into the exhaust system, at a cruise rpm of 2000. That's three strikes against fuel economy. and two against bottom-end power. So you end up with a 5000/5500 rpm engine that with 2.76 or less gears, that rarely sees more than 3500>4000, and cruises at 2000, leaving a trail of unburned fuel in it's wake.
So, rightaway to recover some bottom-end, you gotta swap in in a higher stall,
and to find performance, you gotta install appropriate gears to match the new powerband,
and with a higher cruise rpm to slam the door on reversion.
But it's worse than that! To cruise that cam at 2000, she will want a ton of timing advance, maybe 56 to 60 degrees, but your 318 distributor has maybe 28 mechanical by 4000, and you set the idle-timing to 18 with your new "race-cam", and the VA is pulling say 12*, for a grand total of say 44@2000 cruise, and 32@ 2000 for Power, so you know, to prevent detonation and run-on, you gotta run premium fuel at 8/1 Scr ! That's crazy.
That cam, in a 318, wants at least 10.4 Scr, and it's still gonna have a soft bottom end!
But some guys here recommend that cam as often as they can. NOT ME; been there done that, never again.

If I had to run a 268/276 cam in a 318, I'm tightening it up to at least 108. Then;
I'm installing alloy heads, and flat-tops at 11/1 to get a compression duration of 120 degrees, a CCP of ~188psi a centered overlap of 56*, and a powerstroke of 112, which I know I can tune to deep into the 20s mpg, while cruising at 2000rpm, with adequate timing.
This combo would, for a 318, have a mountain of bottom end torque; more than any stock 360 ever had .
But I wouldn't run even this 268/108 cam in a DD318 regardless, because, the powerpeak is just way to high for 2.76 gears. I mean Second gear is like 110 mph@5500........
Since I'm gonna run an overdrive, I am free to put Second gear where I want it, and when I do that, Suddenly I find that at 188psi, I have way more first gear, even second, than the chassis can handle so I pull out that 268/108 cam, with it's 56* of overlap, and go down say a size and a half to say 258/264/107; with overlap reduced to 47, powerstroke increased to 120, and compression degrees increased to 125* and so, I can drop the Scr to say 10.0, for pressure around 174psi. This will end up with the same bottom end, but 9 less degrees of overlap, so will get better fuel economy at 65=2000rpm, while bringing the powerband down to match the new overdrive transmission. First and Second gear, will now , with say 4.30s, be every bit as strong or stronger than the previous 2.76s. and 5500 in Second is now ~70mph, a much more street-performance friendly; and 65=2400, a number for which you can recurve your distributor to provide the required say 56 degrees.
>Like I said, this is what I would do, if I had a 318DD.
But, with a 360DD, it wouldn't be much different.
>So, the bottom line is this; for a 318DD;
Forget any 114 Lsa performance cam; it is a money pit. It will cost you a Convertor, a set of gears, and dollars at the pump at every fill-up.
>In the long run, a set of pistons and hi-compression alloy heads will, by comparison, look cheap. My OOTB Eddies paid for themselves in less than three years, for these reasons;
geared typically for 65=2000, with
proper cruise- timing, and
because she burned 87E10, full time, without detonation.
>Tire-frying torque was just a side benefit.
 
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