Degree an installed/unknown camshaft

[AJ/FormS]

In the end my question becomes, can i stay with this cam if retarding it or am i looking in getting another camshaft?

IMO, going to a an earlier closing intake is not advisable in this engine's current configuration
Nor is swapping to a solid lifter cam, which, with the same .050 numbers, will have an earlier ICA at advertised ,and so the pressure will climb even higher than the current too-high-for-your-gasoline numbers.
Retarding this cam is a poor solution as the pressure will not change more than perhaps 5, or 6 psi at most, within the normal amount of adjustment. This meager pressure reduction IMO will not be enough.
And you still have the PV issue to prove adequate.
With iron heads, you need something like 160psi tops with a tight-Q; and 155 with open-chambers no-Q.

 

[Wietse]

Roger, so i should leave this cam as it is currently installed?
Man, you feel like the fire under my heels....i need to get after it and get this engine out and back in with all **** done to get after it.

I did had the engine to idle with a good AFR of around 14.
At cruising speeds i had numbers between 12 and 13 AFR, once pushing it and the secondary's open the AFR would lean out a bit too much but i have a set of jets a size up for that ready.
At this point i found a rattling noise, which ended up being my header cracked at #3 cylinder and had to stop to attend repairs.

I just checked my carb out for the transition slot, see pictures.
Manually pushed the choke linkage out of the way and dropped it on the curb idle screw, guess these transition slots are too short.
The 2 holes that can be seen near the bottom face of the carb are, i assume, the idle-discharge holes right?
Near the l/h butterfly is another hole that can be partially seen, think this is ported vacuum signal?
I heard before about drilling those holes in the valves, indeed i always played with the idle adjustment screws only.
I do have a PCV valve installed, it is quite new but have never looked at it if it is still working.
Anyway i will clean it out and make sure it works before reinstalling it back on the engine.

Below are the timing curves that come with the distributor, if i need to get the all-in above 3400 i should go for the 2 silver (heavy) springs which would get me around 3300-3400 if i stay with the black bushing. (Diagram A)
I might need to change it if the initial ends up lower then now to get 32-34 total and this will increase the all-in point again. (worries for later though)

 

[Wietse]

Just took a rocker off to do a decent measurement but 100% sure it is a 1.6 ratio.

 

[PRHeads]

so i should leave this cam as it is currently installed?

That wouldn’t be an option in my mind...... period.
(But it’s not my car)

You’re already this far along...... might as well just pull it out and see if there’s any numbers on it.

 

[AJ/FormS]

I did had the engine to idle with a good AFR of around 14.

14@idle is Too too lean in that combo, and is probably the root of your poor idle; and points straight to the transfer slots being too far closed.

guess these transition slots are too short.

Hyup

The 2 holes that can be seen near the bottom face of the carb are, i assume, the idle-discharge holes right?

Hyup

Near the l/h butterfly is another hole that can be partially seen, think this is ported vacuum signal?

I can't see it but the Sparkport is well above the blades. Anything below the blades are manifold vacuum taps.

should go for the 2 silver

Either the A or the B curve is where I would start for this combo at 200 psi. It might be a lil sluggish out of the gate, but it really depends on your flash stall, and it's relative; as in sluggish compared to what: a faster curve that is detonating?

That wouldn’t be an option in my mind...... period.
(But it’s not my car)

I agree;
but to give it up will be expensive. It's totally wrong for 3.55s and the Scr is totally wrong for a smaller cam. Basically, you will need new lower compression pistons and/or different heads, to go with a smaller cam. If you want to keep the power of the 235cam that looks to be in there now, then you will need a solid-lifter pkg. But IMO a 235 solid is still too much for 3.55s and a sub-3000flash-stall TC
.......... or did I read that wrong?
As for me I would pull that cam out in a heartbeat.

 

[Wietse]

What options does it leave me?
*Leave this cam and live with it, after building everything back i follow up on your advice on setting the car up to get it to run as good as possible, leave the 4.10 ratio gearing and the converter as it is.
And continue to burn those rear tires ..... sorry couldn't resist.

*Or, pull the heads, change/modify pistons and/or cylinder heads, change camshaft to fit my purpose and set it up with the right converter and the wanted 3.55 gears.

14@idle is Too too lean in that combo, and is probably the root of your poor idle; and points straight to the transfer slots being too far closed.

So, for idle better aim for how much AFR? 12.5-13.0?

You’re already this far along...... might as well just pull it out and see if there’s any numbers on it.

In the end it does not really matter what cam it is exactly, i guess we know enough of the animal to decide what options are there.
All in all, once the engine is out i can pull it, no problem, just to be exact.

If these above options is the only options, i will live with this camshaft.
I don't want to go to the extend of partially rebuilding an engine that is in good shape, at least i know it is what it is and just have to make the most out of it.
If it was an engine lurking oil and smoking like a steam train and just dying to get a full overhaul, yes i will start all over again and make it the way i want.

 

[AJ/FormS]

So, for idle better aim for how much AFR? 12.5-13.0?

At idle I would ignore the AFR gauge completely, at lies, lies, lies. Well maybe it doesn't but the gas flow and poor running are confusing the crap out of it. Then if you have any fresh air getting into the header upstream of the sensor, well that will make it crazy. With this combo, I would just ignore it at idle.
Instead trust your senses when twiddling the twiddleables. The engine will tell you when it's unhappy.

If you keep this combo, I highly recommend installing a knock sensor, because with a combo like yours, it is bound to be too noisy to accurately hear and judge detonation. If you miss it once too often you could lose the entire engine;not just the pistons.
Detonation is sorta like driving a nail into a board. You can use a big hammer, and drive it in with 3 blows. Or you can use a smaller hammer and take 20 blows, but eventually the nail gets driven. The engine rarely drops skirts the first time it detonates; sometimes it's the accumulation over time that one day just cracks one off. And no one can predict where the pieces go.
It's probably better tho than dropping a valve tho.

 

[Wietse]

Either the A or the B curve is where I would start for this combo at 200 psi. It might be a lil sluggish out of the gate, but it really depends on your flash stall, and it's relative; as in sluggish compared to what: a faster curve that is detonating?

I always was on the D curve (2 blue springs) and without the vacuum canister connected it never suffered from detonation.

Yeah, when playing with settings just by the ear i could get it to run better, but maybe focussed to much on that AFR meter.
After not looking at it and just set it by ears and vacuum, then seeing a rich mixture i did change things again to get the AFR up to 14-14.5 again.
Thinking doing good, but seems it was the bad thing to do.

 

[AJ/FormS]

I always was on the D curve (2 blue springs) and without the vacuum canister connected it never suffered from detonation.

I cannot comprehend this statement.
First; at WOT, the Vcan goes dead.
Second with 200 psi and iron heads, there are maybe a handful of guys in America who might be able to make that work, on your gas, with a 3000 or less flash-stall TC, and I doubt they would be trying it with 36* at 2500 rpm.
So this goes back to what I said a long time ago; I would get a second opinion on the pressure. If it turns out the pressure is far less than200psi, then we, (I guess mostly me), are all working from the wrong perspective.

 

[Wietse]

Ok, but i am miles away from doing a new compression test.
Yes, i could build back the valve train, intake, carb and close the sump and do a cold crank.
But i guess that would not give an actual reading right? Engine should be at operating temperature?

 

[AJ/FormS]

Ok, but i am miles away from doing a new compression test.
Yes, i could build back the valve train, intake, carb and close the sump and do a cold crank.
But i guess that would not give an actual reading right? Engine should be at operating temperature?

oh,I didn't know it was that far apart!
The carb and intake could stay off, no problem. The valve train should be operational. And it would be prudent for the oilpump to be sucking oil. And I would be using a different compression tester. Just crank until you get two consecutive same/near same, pressure readings.
At this point, I'm not trusting the earlier 200psi readings; or not trusting the statement; "without the vacuum canister connected it never suffered from detonation."
Something is not making sense to me, and the most likely solution is the pressure verification.
The other conclusion is that you are having issues identifying detonation.
And the third conclusion would be that your 95 pump gas is some better gas than our 93 (R+M)/2
The thing is; I hear guys in Europe and NZ, running 160/165 or less sometimes and having detonation issues.
Waitaminute!.....What's your elevation there?...I was assuming close to sealevel

 

[wyrmrider]

W
what's the bottom line
I've been away
advanced or not?
and you said timing chain slop
how bad?
you can spin the motor over 1 turnoff the crank and turn the cam half turn if it would make more sense on the dot to dot for you
would put the 6 at 1
really makes no difference but sometimes easier to visualize
I'll try and catch up tomorrow

 

[Wietse]

I will have a look to get another gauge to put on that compression tester.
But mine has this check valve before the gauge so when cranking the pressure remains trapped at the gauge.
I need to put it up somehow so i can see it when cranking.

Edit: I just checked my compression meter against 2 gauges on my air compressor and at 120 PSI (on the compressor) the test gauge shows 124 PSI.
At lower pressures it was same, 4-5psi higher then the compressor gauges.

If it really had detonation it would have been a goner already i guess because i have been driving it over 800-1000 miles with the current setup. Only carb was changed recently.
But yeah, how to identity detonation, the only thing i can hear when the vacuum advance was connected is this tingling sound in the exhaust, sounds like there are some little stones inside rattling on the pipe.

And am close to sea level indeed, actually my town is probably at -1 meter below sea level

So the cold cranking compression is something to work with?
It has not run for several weeks now so piston rings and liner will be "dry" of oil by now.

@wyrmrider:
The cam seems 1 tooth advanced as in the pictures, when crankshaft sprocket is facing up the cam gear dot has moved along 1 tooth.
Chain has little slack but i guess not excessive.
I assumed the dots on the gears alway line up at the cyl #1 @compression stroke, that's why i figured how it is possible to be off but indeed it can be at any location really.

 

[miller]

When your chain gear dots are dot to dot, #1 is on exhaust stroke. It's #6 that's on compression stroke.

btw. Real interesting read!

 

[Wietse]

When your chain gear dots are dot to dot, #1 is on exhaust stroke. It's #6 that's on compression stroke.

Thx. But that is strange IMO, all other engines i worked on the #1 TDC (compression stroke) the distribution alignment marks also line up.
Still learning every day on these engines

Well yeah, for me it is interesting for sure.
I mean, most here would have given up on me already but thanks to the guys here helping me out trying to get this thing to work.
Bear in mind that these cars are liked here in the Netherlands but finding good help like from you guys over here is not easy, so here i am kind of on my own.

I started building back what is required to do a cold compression test, hopefully i can get some readings soon.
I did check for another compression tester but i will have to order one and it will take time.
As i checked this gauge against the gauges on my compressor i can assume it is very close to truth.

 

[miller]

Yep. Threw me off, first working on them. Young and dumb, back then...still kinda dumb. That's for fresh engine builds. Just the positioning of the crank/cam, to set the chain.
But, I'm not a cam guy. Too many dang numbers. Wealth of good reads on it, from these guys!

 

[Wietse]

But, I'm not a cam guy. Too many dang numbers.

Well...
You take care of the popcorn, i have no time for it as i am running up and down the garage trying to figure things out!
Think by the time this is over we can call ourselves experts as well

I am getting ready to do a compression test, previously tried to crank but forgot i removed the bolts between converter and flex plate so i was priming the tranny....
i will try to get a squirt of oil in there to get some sealing, actually i will try without oil first.

TBC soon!

 

[miller]

Carb at WOT. Three hits on the gauge. How I was told.

 

[Wietse]

No carb installed, no intake either...

Ok, so when cranking 3-4 times i get 150-155 PSI.
When continue cranking until it the gauge will no longer increase i am gettin 175-185 PSI. (2-3 stroke pulses but no longer increasing)
I tried this on 3 cylinders (1,2 & 8) and testing a second time ends up with the same.
I have not tried with oil inside, then again not really sure i should as this normally can be done to check the condition of the piston rings with low pressure issues.

 

[wyrmrider]

good pic thanks
easier to see dot to dot when you are on #6
that crank gear only has one slot?
Too bad we can't advance 4 degrees to simulate what an 8 degree shorter cam (installed at the same LCA moving the intake 4 degrees) would be
perhaps AJ will rerun his numbers
you can do a lot at current compression