The Force Awakens...

Ira, Its a shame you didn’t call me when you visited NY, I live only about 1.5 hrs at the most from the airport.
I have an extra distributor for a 71 all set-up and ready, rebuilt by Lars for maximum performance in a mild Csb.
 
chromebumpers said:
58 degrees is too high. The max is what, 51/52? but too high and you get chugging. All this under light load and cruise speed.
Your best torque and hp is at WOT and all in at total advance of 36 degrees
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Yes, I clocked it in at those specs. My guess is that after I get those plug wires replaced, the ignition, for now, will be as good as we can get it. That and maybe some weaker springs to get mechanical to come in faster.


The next step will be to tune the carb. I suspect it need to be jetted down at WOT.
 
chromebumpers said:
Ira, Its a shame you didn’t call me when you visited NY, I live only about 1.5 hrs at the most from the airport.
I have an extra distributor for a 71 all set-up and ready, rebuilt by Lars for maximum performance in a mild Csb.
Click to expand...

A shame indeed, it would have been very cool to meet you as well !
 
DorianL said:
Thanks, Chrome! That helps !!!

Well Gents, I spent a lot of time this weekend tinkering on the ignition; more than I should have due to my own incompetence including forgetting to reconnect the vacuum advance prior to a test drive. The test drive, of course, surprised me with unexpected results. I decided to pull all the plugs... and broke one. :mad: Only after that did I discover my oversight and go for another test drive. This evening I'll pull the plugs again and check the coloration; with the vacuum leak they looked a tick white but clean. No oil or fuel.

Test drive results: With the vacuum advance reconnected (no leaks);
The engine behaves reasonably well overall;
It seems to have significantly more mid range power and throttle response; (quite impressive actually)
Mid throttle is very good. WOT, however, is sluggish.
Cruising at 60 is fairly comfortable (finally!); if loud and annoying at 2800 rpm;
The idle, at 850 rpm, has a vacuum reading with a needle that vibrates rapidly between 20-24 in/Hg; the vibration flattens out at higher RPM. At 2000 rpm, the vibration is mostly gone with the needle stabilizing at 24 in/Hg;
The idle is generally smooth with what sounds like the occasional miss or maybe light popping in the mufflers;
The pops in the muffler get louder on deceleration during the test drive.

Ignition adjustment: Tinkering around, I settled on...
Initial: 14 degrees
Centrifugal: 23 degrees
Mechanical: 37 degrees (begins at 1500 rpm - all in by 2600 rpm)
Vacuum advance: starts at 5 degrees and ends at 14 degrees at 15 in/Hg (I positively limited the advance with a stop)
Total: 51 degrees

Other observations:
That carb seems to get quite hot. I would think phenolic space might be a good idea.
Plug wires need to be replaced; one has a very good burn in it.
The carb has yet to be tuned beyond idle. It is a bone stock Edelbrock 750 CFM. Stock rod, jets, springs, etc.
I haven't driven it enough yet to see if it remains cool at idle. For the moment it does seem to be running cooler.
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Edelbrock carbs are nice for Low Po Street Engines.
I have found them to limited once 450 + HP is there.
They work nice day in day out driving.
With all aluminum construction they absorb heat rapid in the summer.
Fuel boils in the float bowl. Todays Pump gas.
With Race gasoline Fuel boiling is a non issue.
Holley 4bbl older models & Street Avenger are Zinc aluminum construction they do not absoarb or heat soak as rapid.

Need that New Radiator.
Get Coolant temps down to 160-180F cruising steady.

With pump gasoline boiling in the carb float bowl its impossible to Tune correct.

If Your Willing to Cut And Fit the Griffin Pro Series Radiators is Best for cooling.
Just a Huge Radiator made to cool off 1000 Hp Race engines on the street.
 
I still have not found a Fan that works as Good as My stock original 1970 TA 5-blade Mechanical Flex Fan.
Pontiac Engineers knew their Stuff.

Closer you can get to 10,000 cfm airflow the better.
Real Test is letting the car idle for 1 hour after driving 70-100 MPH on a 90-100 F day.
Does not overheat.
Coolant temps stay 160-180F.
Simulate Chicago accident traffic jams for me.

I need 1 more electric Fan on my 63 GP.
Holds 160-165 F on the Highway all the time with the massive Griffin Pro Series Radiator made for a 496 BBC 1st Gen Camaro with 1000 HP.
 
Maniacmechanic1 said:
. . . . . . . . .
If Your Willing to Cut And Fit the Griffin Pro Series Radiators is Best for cooling.
Just a Huge Radiator made to cool off 1000 Hp Race engines on the street.
Click to expand...

Really? There’s no pro series Griffin radiators to fit a C3 without cutting? That sucks. You would think there is enough need for Griffin to make a bolt in radiator for the C3 yrs.
 
chromebumpers said:
Really? There’s no pro series Griffin radiators to fit a C3 without cutting? That sucks. You would think there is enough need for Griffin to make a bolt in radiator for the C3 yrs.
Click to expand...
I have not looked.
Need stock 1971-72 C3 SBC & 454 BBC Size.
Pro series Griffin was made for Drag Racers.
Cost is 1/2 of all others because no Auto Trans Cooler intergrated is offer Pro Series.
Never made to Pro Tour style.
Fab.
Was easy in the 63 Pontiac .

At least 200 sizes offered I recall from Griffin.
 
chromebumpers said:
Really? There’s no pro series Griffin radiators to fit a C3 without cutting? That sucks. You would think there is enough need for Griffin to make a bolt in radiator for the C3 yrs.
Click to expand...
I will look around later today.

Otherwise Dewitts and all adds up to $800-1000 Pro Tour .
 
On Lunch.
Looking.
Man the Corvette Tax Sure applies.
Forgot about the Unique C1-C3 Inlet and Outlet hose connections.
Expensive.
Looking at 454 BBC.
Max cooling behind a 355 SBC then.
 
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