1970 LT-1 Engine/Spark Plug Question
Thread Starter
Drifting
Joined: Oct 2001
Posts: 1,290
Likes: 186
From: Naples FL
1970 LT-1 Engine/Spark Plug Question
I don't have my owners manual with me.....and I want to confirm what the correct spark plug number is (Champion, I assume), and what the gap setting is? Thanks!
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
Originally Posted by Ironcross
A better choice would be a AC R45. Less likely to fuel foul as would a R43. 43`s are a little cold for everyday driving 
I use the 45's in my 70 L-46.(which calls for a R-44). The A/C r43 is the factory correct plug for the 70 LT1, if thats what you wanted to know. Although you'll find the 45's easier to get.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,502
From: Little Rock AR
Originally Posted by Ironcross
A better choice would be a AC R45. Less likely to fuel foul as would a R43. 43`s are a little cold for everyday driving
43's were fouling out in my 302. Switched over to 45's and she runs/idles MUCH better. -Mark.
Safety Car
Joined: Dec 1999
Posts: 3,602
Likes: 837
From: PA
Originally Posted by Ironcross
A better choice would be a AC R45. Less likely to fuel foul as would a R43. 43`s are a little cold for everyday driving
Excellent advice...
Go with 45s or 46s for the street. Much better choice for daily driving... You'll be less likely to foul the plugs in stop and go driving.
Save the 43s for the track.
Regards,
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
R45 vrs R45"S"
Both of these plugs have the same heat range but the "S" sufix means extended tip. Most Vette engines can get away with the "S", but it has had some interference problems with the piston dome with the 11-1 compression engines. Ask how I know, well from personal experience. I closed up several in my 61 315/283 FI piece and had to take it back apart on a seriously hot Miami day as a South Miami parts store sold me the 44S instead of plain 44`s. Consider the plug shielding, air cleaner removal and and replacement of all that junk, plus the fact that the engine got hot after firing the sucker with the wrong plug after several had closed up by hitting the piston dome. By that time everything was super hot. The Miami sun, the engine, and principally me because I had to do it all over again. My fraturnity brothers could tell by the words coming out of my mouth. Anyway, the plug set without the "S" extended tip is maybe a safer choice. 
PS, it actually even got worse as I chipped the paint on the opposite fender as a plug went flying from the socket handle on the second time around.
PS, it actually even got worse as I chipped the paint on the opposite fender as a plug went flying from the socket handle on the second time around.
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