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Re: Smoke!! Help! (8/18)
 11/14/20 12:43pm
73shark
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 693

Bluesting 70 said:

I don’t it’s coolant because it passed two combustion leak tests. 73Shark, is there a way to test to see if it’s valve seals or guides?



Not that I'm aware of.  Are you seeing any increase in oil consumption?



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1973 L-82 4 spd

Re: Smoke!! Help! (9/18)
 11/14/20 3:27pm
Bluesting 70
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1970 Blue Convertible with pipes and flares


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Posts: 27

73shark said:
Bluesting 70 said:

I don’t it’s coolant because it passed two combustion leak tests. 73Shark, is there a way to test to see if it’s valve seals or guides?



Not that I'm aware of.  Are you seeing any increase in oil consumption?


I’m not. But then again, I haven’t been driving it much at all. I’m planning on pulling the block out soon for bay clean up and paint as well as a few other things.

I appreciate the feedback from all of you. Any suggestions on what I should di while the block is out?  I was considering upgrading the heads. 

Re: Smoke!! Help! (10/18)
 11/14/20 6:51pm
Bluesting 70
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One other thing o meant to mention, it’s dieseling pretty bad at cut off. It’s done that before but much more now. 

Re: Smoke!! Help! (11/18)
 11/14/20 11:11pm
73shark
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 693

Bluesting 70 said:

One other thing o meant to mention, it’s dieseling pretty bad at cut off. It’s done that before but much more now. 

Since you apparently have a 1970 and if it's not an LT-1, then I assume it still has the original Quadrajet carburetor. Dieseling can be caused by the idle stop solenoid not adjusted right or malfunctioning.
When the engine is shut off, the solenoid denergizes and allows the throttle to completely closed. That shuts off any air to the engine and prevents dieseling.

Edit: I saw in your first post that you do not have the stock carburetor. I don't know if the Edelbrock carburetor utilizes an idle stop solenoid. Other things that can cause dieseling are carbon buildup in the combustion chamber and/or the incorrect heat spark plugs.

If the engine is a small block, you could upgrade with stock LT-1 high-cmpression heads and large intakes. Then you could add the 11:1 pistons.  When I rebuilt mine, I kept the original L-82 heads and put in the 11:1 pistons because I did an .030" over bore.



|UPDATED|11/14/2020 8:11:08 PM (AZT)|/UPDATED|


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1973 L-82 4 spd

Re: Smoke!! Help! (12/18)
 11/15/20 2:47pm
manchestersharkLifetime Member
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Equinunk, PA - USA

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1972 conv, 4-speed, 350, 200hp, numbers match, rally wheels, war bonnett yellow w/white top. good condition, nice driver.


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Posts: 2058

Check timing for dieseling.

Re: Smoke!! Help! (13/18)
 11/15/20 3:35pm
Bluesting 70
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1970 Blue Convertible with pipes and flares


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73shark said:
Bluesting 70 said:

One other thing o meant to mention, it’s dieseling pretty bad at cut off. It’s done that before but much more now. 

Since you apparently have a 1970 and if it's not an LT-1, then I assume it still has the original Quadrajet carburetor. Dieseling can be caused by the idle stop solenoid not adjusted right or malfunctioning.
When the engine is shut off, the solenoid denergizes and allows the throttle to completely closed. That shuts off any air to the engine and prevents dieseling.

Edit: I saw in your first post that you do not have the stock carburetor. I don't know if the Edelbrock carburetor utilizes an idle stop solenoid. Other things that can cause dieseling are carbon buildup in the combustion chamber and/or the incorrect heat spark plugs.

If the engine is a small block, you could upgrade with stock LT-1 high-cmpression heads and large intakes. Then you could add the 11:1 pistons.  When I rebuilt mine, I kept the original L-82 heads and put in the 11:1 pistons because I did an .030" over bore.






Re: Smoke!! Help! (14/18)
 11/15/20 3:36pm
Bluesting 70
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Posts: 27

manchestershark said:

Check timing for dieseling.



Good point in the timing. I didn’t build the engine so I don’t know what timing it should be but I run it at 12-14 idle and 30-32 total. I figured that was safe enough. 

Re: Smoke!! Help! (15/18)
 11/15/20 3:43pm
Bluesting 70
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1970 Blue Convertible with pipes and flares


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Posts: 27

73shark said:
Bluesting 70 said:

One other thing o meant to mention, it’s dieseling pretty bad at cut off. It’s done that before but much more now. 

Since you apparently have a 1970 and if it's not an LT-1, then I assume it still has the original Quadrajet carburetor. Dieseling can be caused by the idle stop solenoid not adjusted right or malfunctioning.
When the engine is shut off, the solenoid denergizes and allows the throttle to completely closed. That shuts off any air to the engine and prevents dieseling.

Edit: I saw in your first post that you do not have the stock carburetor. I don't know if the Edelbrock carburetor utilizes an idle stop solenoid. Other things that can cause dieseling are carbon buildup in the combustion chamber and/or the incorrect heat spark plugs.

If the engine is a small block, you could upgrade with stock LT-1 high-cmpression heads and large intakes. Then you could add the 11:1 pistons.  When I rebuilt mine, I kept the original L-82 heads and put in the 11:1 pistons because I did an .030" over bore.




Did you get a lot more horse  power off that set up?  I figure I have a good chance to really get it right while I have it out and wouldn’t mind upgrading for a little more power. My vin matches on the block so I’m assuming it’s the original block.  It’s an L46 which came with 11:1 compression.......I believe. 

Re: Smoke!! Help! (16/18)
 11/24/20 12:37am
73shark
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 693

Haven't fired it up yet.  With my low-compression heads, the 11:1 pistons will give me a CR of 10:1.

Dieseling can be caused by carbon deposits that can get red-hot and will ignite the fuel-air mixture until they cool off.  That's why GM uses an idle stop solenoid that allows the throttle plates to completely close thereby preventing any sir to mix w/ the fuel which prevents dieseling.

Edit: I believe the L-46  (350/350) has the 2.02 intake valves and 11:1 CR.  Probably the two easiest power adders would be a cam and headers.  Of course you could go w/ a blower like a ProCharger but your CR might make that a little dicey.



|UPDATED|11/23/2020 9:37:47 PM (AZT)|/UPDATED|


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1973 L-82 4 spd

Re: Smoke!! Help! (17/18)
 12/3/20 8:00pm
Bluesting 70
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Well, I decided to get a 383 built from Skip White Performance. I’ll have it in a few weeks. However, I’m keeping the original block on a stand. My son and I will rebuild it as a father and son project. 

Re: Smoke!! Help! (18/18)
 12/5/20 3:38am
73shark
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 693

How does that compare to a Chevy crate engine? 



______________

1973 L-82 4 spd

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