Chasing down detonation w/UPDATE!

[JerseyJoe]

Ron,
   I completely overlooked the aspect of Winter gas. Hopefully this will lead to "no problemo" when the blend changes.

INTMD8,
   I assembled the engine myself and did verify TDC on #1 and the pointer on the balancer with my dial indicator, bridge, etc...

Russ,
    When I installed the cam I did not use the crank sprocket keyway for advanced or retard, I used the "O" mark. Then checked it with the degree wheel.

Stay warm everybody. I wont be wrenching until it's warmer next week!

[BSB67]

Right.  So what did the degree wheel say?   What is your elevation?  I'm trying to establish if the 175 psi makes sense.  Do you have another gauge you can try?

[c00nhunterjoe]

Ron,
    It completely overlooked the aspect of Winter gas. Hopefully this will lead to "no problemo" when the blend changes.

INTMD8,
    I assembled the engine myself and did verify TDC on #1 and the pointer on the balancer with my dial indicator, bridge, etc...

Russ,
     When I installed the cam I did not use the crank sprocket keyway for advanced or retard, I used the "O" mark. Then checked it with the degree wheel.

Stay warm everybody. I wont be wrenching until it's warmer next week!

What russ is getting at is "straight up" on that cam grind is actually 4 degrees advanced. So the degree wheel would verify that.

[JerseyJoe]

Sorry guys, Everything checked out with what the cam card said, and that grind is 4 degrees advanced.
I'm in Southern New Jersey, most of which is sea level to around 200 feet above sea level. Google says where I live is 20 feet.
So the air is pretty dense compared to higher elevations.
I only have one compression tester but I can borrow a different brand or pick one up.

[BSB67]

Sorry guys, Everything checked out with what the cam card said, and that grind is 4 degrees advanced.
I'm in Southern New Jersey, most of which is sea level to around 200 feet above sea level. Google says where I live is 20 feet.
So the air is pretty dense compared to higher elevations.
I only have one compression tester but I can borrow a different brand or pick one up.

So here is where I'm at right now.   Using everything but your cylinder pressure (IVC, CR, elevation) suggests to me you might not be able to run pump gas detonation free.  Your measured cylinder pressure suggests that you should be able to run detonation free.  I do recommend that you verify the cylinder pressure with another gauge.  Make sure that the schrader valve opens smoothly with a vey light touch, and actually watch the needle when cranking to verify its not leaking back a little before the valve closes. Do this with two gauges as a check/verification.

Also, in your case, it is more important to do the compression testing as hot as you can.  The expansion of the aluminum cylinder head will open the lash 0.006"- 0.007" and have a meaningful impact on valve seat timing and therefore cylinder pressure (10 psi or so) too.

As stated, winter fuel blend in some location will be more prone to detonation.

Good luck.  Report back.

[Kern Dog]

I had a situation where I was getting a 220-230 PSI number with a gauge. THEN I looked closer at it and noticed that the needle was resting at the 30 mark. 
What ? I tried another gauge and it read 190-195.

[JerseyJoe]

Also, in your case, it is more important to do the compression testing as hot as you can.  The expansion of the aluminum cylinder head will open the lash 0.006"- 0.007" and have a meaningful impact on valve seat timing and therefore cylinder pressure (10 psi or so) too.

Update: It's 66 degrees here today! Thanks for hanging in with me on this.
      Taped a non-filled gauge to the windshield (it was reading 10 psi), readjusted the regulator, and drove it. No drop in fuel pressure at WOT. It stayed around 7-1/2 psi.
Took it home, and jetted up 3 sizes to 89 primary/90 secondary (I have one set of jets) and then did a compression test while it was still hot.
Russ, you're right on. 5 or 6 cranks got it just a tick below 200 & up to 205 (didn't get a chance to get a different gauge though, I'll still check with another one). I think I see where this is going.

So the only thing I changed today was jet up and lowered fuel pressure to 7.5psi
Took it out again, it really liked more jetting. Part-throttle ping is barely there, you might miss it if I wasn't trying for it.
Got out on the highway and had a few good pulls in 2nd and 3rd up to WOT. Most objective I can be is it's less rattle/more ping if that makes sense?
And it's coming in later, well past 3/4 throttle and much closer to WOT. But I think it's heading in the right direction.

I'm already .051 in the hole, should I consider thicker head gaskets and be done with it?
Colder plug?
Cam with different intake closing?

With just a few tweaks this car is really becoming a MONSTER and I should be happy it's running this well up to WOT... but we don't build for half throttle, do we?  

[BSB67]

So at 200 - 205, I'm not too sure you'll make it.  IIRC you've done most everything suggested.  The ping at WOT is the one that is harder to fix.  Try the next step cooler plug, and tighten the lash 0.004", see what that does.  After that retard the cam 2°.  If your still not there, then head gasket time.

[c00nhunterjoe]

Well russ beat me to it. Colder plug, then retard the cam. So thats 2 votes there. You could also drop 2 more degrees of total out of it before you mess with the cam. See if the pinging quits with that and a colder plug 1st and how much it affects performance.

[BSB67]

Also after you try those items, and if your still not quite there you could hit the pause button until your back on summer blend gasoline.

[JerseyJoe]

So at 200 - 205, I'm not too sure you'll make it.  IIRC you've done most everything suggested.  The ping at WOT is the one that is harder to fix.  Try the next step cooler plug, and tighten the lash 0.004", see what that does.  After that retard the cam 2°.  If your still not there, then head gasket time.

Haven't done the 160 thermostat yet, it came yesterday. And I still have the uncoated headers on.

Hope this isn't a dumb question... Tighten the lash on both intake and exhaust? If so, that brings me to .012/intake & .014/exhaust if that's not too tight.

Anybody got suggestions for an 8 heat range plug?

Thanks Russ, Ron, and Joe, These are easy fixes I just wouldn't have known where to start.

[BSB67]

Just the intake.
0.012" will be fine. 
Curious, what exactly is your current intake lash (sounds like 0.016" but want to confirm) setting? when was the last time you set it?  was it set hot, or cold? And have you ever checked the cold lash?

[JerseyJoe]

Just the intake.
0.012" will be fine.  
Curious, what exactly is your current intake lash (sounds like 0.016" but want to confirm) setting? when was the last time you set it?  was it set hot, or cold? And have you ever checked the cold lash?

Recommended is .016 on the intake and I did it hot but it was this past July. I've only put about 200 miles on it since then. I'll check it to make sure it hasn't loosened up before I take it to .012
Never checked it cold.

[c00nhunterjoe]

I like to set them cold and just account for the aluminum heads in the setting. Setting them "hot" allows for too many variables to take place.

[BSB67]

I like to set them cold and just account for the aluminum heads in the setting. Setting them "hot" allows for too many variables to take place.

This.

So JJ, I recommend checking them cold now, and report back what you get.

[JerseyJoe]

UPDATE!
Well, it rained for the last four months here in the Northeast. And the new header install required removing the torsion bars which lead to doing the entire front suspension, etc...

I'll cut to the chase. It's gone! I had it out in 85 degree heat yesterday and I couldn't make it knock unless I floored it in 3rd down around 25mph (w/3.54 rear).

Here's what I'm running now:
Total timing is now 34 deg. (down from 36)
NGK 8 series plugs, gapped at .038 (started with NGK 6 series)
carb jetted with 90's (started w/84's)
160 deg. Milodon thermostat (was 180)
added 1/2" phenolic carb spacer
3' of DEI "heat sheath" on fuel line along firewall to past the collector
Rainbow Products 17" electric fan, installed as a puller, hidden inside factory shroud, in-town traffic held it to 180 with spikes to 190 sitting at red lights.
Factory clutch fan is gone (original fan clutch was suspect)
Doug's 2" ceramic coated headers, ABSOLUTELY HUGE difference in underhood temps (had uncoated mystery 1 7/8" headers before)
I called Comp Cams and asked what they recommend for valve lash and they said set cold @ .010" & .012" (started with .016" & .018" set hot)

Here's the kicker, It's still got a half tank of winter blend gas in it. I'm very happy with how its running right now but may try some more jetting to see how it goes.
All I can say is, you can never be careless with the power this thing makes.
I can't thank you guys enough. I'd be guessing and probably going in the wrong direction  

[c00nhunterjoe]