If the cam is still installed you can do a quick-check without taking the front off.
1) roll the crank around until # 6 piston is at TDC and on what would be it's compression stroke. You can tell this by the fact that the lifters do not move when you shuttle the crank back and forth. If this is not the case, then the cam is NOT in right; go to step 4.
2) Go to the #1 piston. Lay a straight-edge across the lifters. Shuttle the crank a few degrees either way until the straightedge contacts each of the two lifters in at least two places. The straightedge should be about parallel to the deck. Now read the degrees on the timing tab, relative to the TDC mark on the balancer.
3) Assuming the TDC mark is correct, it should be within about 4 degrees of TDC on the timing tab, and the piston should be within a few thousands of the deck, or at least from TDC. If this is not the case, then the cam is NOT in right; go to step 4.
4) Now you are justified in pulling the front off. When you get there,
Make sure the cam-key is installed and the Bolt is torqued properly
This is just too easy;
when you go to do the New install, you do the exact same thing.
1) You put the #1 piston at TDC.
2) You put the cam in, remove the timing key, rotate it to split-overlap on the #1
3) assemble the chain dot-to-dot, and slip it on.
4) LOOK at the alignment of the keyways:
If the two are not even in the same window; verify numbers 1 and 2
If still synced, one of the sprockets is marked wrong. figure out which way the cam sprocket has to go, and how far, to get into the window, then make it so.
Once the keyways are thus in the ballpark, re-install the cam key, then re-install the timing set.
With the crank thus at TDC#1, and the cam at split overlap on #1, I guarantee the cam-timing is close enough that the engine will run and will run really well. At this point, for a streeter, degreeing the cam is IMO, just a formality.
The cam thus installed, is MOST LIKELY, somewhere between 4 degrees advanced and straight up, +/- maybe 2 degrees; and I guarantee you that only the dyno is gonna find the WOT power difference.
Where the observable power difference will be felt is between stall rpm and about 3200+/-200 rpm, because of the change in cylinder pressure. If you have a typical high-stall convertor around 3000rpm; you may never know if the cam is out, and not knowing, you will never care.
But:
If you have a clutch with hiway gears; well #1, you need to pay closer attention to the combo in the first place, cuz cylinder pressure is gonna make or break the fun-factor.
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Here's my proof;
My first cam, in my 367 combo, was the 292/292/108.
I degreed it at 0* advanced because theoretically with 11.3Scr the cylinder pressure should have been awesome, and the top-end was, but the bottom was IMO pretty soft.
Before the summer was over, I had retimed that cam three more times from 4* retarded to 8* advanced.
Here's the deal, that cam simply did not like the combo of A833/3.55s. It ran like a cat on fire with 4.30s, but even a Smog-era Teener runs pretty good with that combo.
I really wanted to run the 3.55s, having traded away my rarely used 4.10s straight up, to get them. I decided that 292cam was not for me, and sold it straight away, to a racer. BTW, that cam measured about
[email protected]
The point is this; timed anywhere from 8 Advanced to 4 retarded, on the street with street tires, and the A833/3.55 combo, the after-3500 performance difference was immeasurable, by my butt-dyno.
The next cam was a complete blast to drive.. this was a 223/230/
[email protected] and made so much pressure that I ended up running it at 2* retarded, and she loved it, pulling to waaaay past 6000 thru the Edelbrock heads. That cam spent most of it's short life running up to 7000/7200 on the street cuz 60mph was ~7100 at the top of First gear, and the sound of a 367 screaming at 7200 thru dual 3" pipes, to me, was/is, intoxicating. I would never have changed this cam, had it not begun to drop lobes.
The Final cam, installed in 2004 is a 230/237/110 . This cam dropped the cylinder pressure quite a bit, when in at 2* retarded and 10.95 Scr; so it got re-timed to +2*, in the following winter, where it has been ever since.. This brought the pressure to around 177psi..
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I suppose that if you had a low-pressure smaller engine, it might be more sensitive to cylinder pressure loss from cam-timing; but again, with a 3000 stall, I doubt you'll ever feel it.
BUT, with a clutch, I guarantee you can can feel the low-rpm difference.
For a clutched 318, the Wallace Calculator predicts that;
>at 8/1 and Ica of 62* will make 120 psi@ a
V/P of 91, a very modest number
>at 8/1 with an Ica at 58*, this is predicted to climb to 125psi@
V/P of 97. This is an increase of; 97/91=plus 6.6 %, a very worthwhile move.
>at 10/1; and Ica of 58, is predicted to make 168psi@
V/P of 131, and 131/91 is an increase of 44% over base; so your clutched car is gonna really feel that.
read about V/P here;
Cam Timing vs. Compression Analysis
victorylibrary.com
Here is a list of stock Mopes and their approximate V/Ps (per the Wallace) to give you an idea of low-rpm performance, averaged from idle to about 3000 rpm
The 225 is ........................~ 87
The Smog 318 comes in at ~107
the 318 @9.2 is .................. 133
the 340@10/1 is ................~120
the 360@ 8/1 is ................ ~113
the
[email protected] is ................~123 with cam retimed to straight up
the 5.9M I think at 9.2 is ....~154 also retimed to straight up
the '68/440Magnum@10/1
~ 159 cam in at straight up;
A 416 stroker ;
with a 270/276/108 cam, straight up at 9.5 to 1; V/P of 156
With a 276/286/108 cam at 4* advanced and 10/1 V/P of 171
my 367; @11.3
.....~V/P of 170 with the former 223/230/110 cam
My 367; @11.0 .....
~V/P of 158 with the current 230/237/110 cam.
my 367; @11.3.....
~V/P of 143 with the 292/108 cam in at plus 4*
>here you can really see the difference in V/P, going from the 292(249@050) to the
[email protected] (270/276/110Hughes), and why I pulled that stinking 292/108. That 143VP was not what I had wanted.
>As for the swap from the 223 to the 230 cam, I really felt this loss of the V/P, and swapped away the regular A833, for a Commando, to get the lower first gear. After that it was better. The loss of V/P from 170 to 158 was 7.6%. The gain of the low-gear from 2.66 to 3.09, was 16.2% for a net gain of 8.6%, bringing the performance of the 170V/P right back; AND more importantly, the 3.55s were back on the table.
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You might think ,
maybe not, IDK,
that a V/P of 170 is excessive ............ and IMO, you'd be right. But; not in 22 years, have I ever said "dammit I need a stroker"; and, if you ever get a chance to take a low-rpm ride in a car with such a generous V/P, I guarantee that you will be impressed.
For example;
In town, just cruising around, I out-shift at 2800.
This will get me;
20.5 in first, 33.0 in Second, 45.2 in Third, and 63.3 in Fourth; all of which are close to typical speed-limits up here..
On the shifts, the Rs will drop to 1740 into Second, 2040 into Third, and 2000 into Fourth. .................and 65 will be 2140 in GV-overdrive.
So in this example, my powerband needs to be from about 2000 to 2800.
This is where the very-high V/P really really shines.
You guys with low V/P engines, 3.55s, and Manual transmissions, just try this. You're gonna be using a lotta lotta throttle to keep up with me, while my throttle will be barely open. And that's why your city fuel-consumption sucks so bad.
OkOk, enough talk.
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