'70 L46 Gas???
Thread Starter
Drifting
Joined: Feb 2000
Posts: 1,591
Likes: 53
From: Central MN
'70 L46 Gas???
What gas are you all running in your '70 L46 Vette? If it's leaded premium, are you adding a lead additive to today's unleaded premium? Unfortunately, race fuel is not available in my location.
For the last 38 years (I'm 48,) I've wanted a '70 Vette. Well, through Hemming's Motor News, I found a '70 L46 Vette that I really like and am considering purchasing. Assuming I purchase the car, it will be my fifth Corvette ('78 Silver Ann. Edition, '96 CE Coupe, '98 Vert. and my current ride '05 Vert..) The car will be a "trophy car" and will not be used on a daily basis (that's what the '05 is for.)
For the last 38 years (I'm 48,) I've wanted a '70 Vette. Well, through Hemming's Motor News, I found a '70 L46 Vette that I really like and am considering purchasing. Assuming I purchase the car, it will be my fifth Corvette ('78 Silver Ann. Edition, '96 CE Coupe, '98 Vert. and my current ride '05 Vert..) The car will be a "trophy car" and will not be used on a daily basis (that's what the '05 is for.)
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
The lead is not going to be the issue. It is the octane you need to worry about. You are running a 11:1 motor providing nothing has been changed. You are going to have to back down the timing or find some octane boost or mix in some race gas. Leaded fuels have not been around my area for years and it has not been a problem. It does not sound like you are going to put on many miles so the absence of lead won't be a real problem. My dad had a L46 Vette and used to mix in 1 gallon of race gas to a fill up of premium and that stopped any pinging problems.
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The need for lead is a long perpetuated myth. All of my older high compression Vettes including a 65 L79 350 horse and a 68 427/390 all run fine on unleaded pump gas, 93 Octane with no additives and no hardened valve seats. They don't ping or overheat and I have not retarded the timing. The engine in the 65 was last re-built in 87 and I have had no issues other than the plugs burn cleaner on unleaded than they used to on leaded.
Drifting
Joined: Jul 2006
Posts: 1,259
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From: Deplorableville Nebraska
The need for lead is a long perpetuated myth. All of my older high compression Vettes including a 65 L79 350 horse and a 68 427/390 all run fine on unleaded pump gas, 93 Octane with no additives and no hardened valve seats. They don't ping or overheat and I have not retarded the timing.
I've had my "70 L46 coupe for 18 years now. Started out feeling I should boost the gas with whatever I could find. After a short while, I found out 93 Octane worked just fine. 76,000 miles, original 11:1 compression, no pinging, no problems.
Thread Starter
Drifting
Joined: Feb 2000
Posts: 1,591
Likes: 53
From: Central MN
Everybody.........Thanks for your replies. So, the leaded gas issue is a myth - that's good to know. On the other hand, with 11:1 compression (the car is bone stock with 36K miles on the ticker) octane is more of the issue. It's easy to find 91 & 92 octane (that's what I put in the '05) at the local gas stations, but finding 93 is a bit tougher. Who sells 93 at the pumps? Also, if you're adding an octane booster, what brands do you recommend and where is a good place to buy it (online?)
I'm getting very close to purchasing the car. It's a '70 L46 Laguna Gray Metallic / Black coupe. The VIN is 194370s413558. Other than a T&T steering wheel (N37,) the only options are performance options: L46, M21 & ZQ9. I've hired a professional inspector to inspect the car and, assuming his report is good, it's a "done deal."
I'm getting very close to purchasing the car. It's a '70 L46 Laguna Gray Metallic / Black coupe. The VIN is 194370s413558. Other than a T&T steering wheel (N37,) the only options are performance options: L46, M21 & ZQ9. I've hired a professional inspector to inspect the car and, assuming his report is good, it's a "done deal."
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
Had mine since 73 and have tinkered with fuel since leaded went by by.
(1)You can use aviation fuel if you have access. My 70 L-46 runs best on that.
(2)Next best thing... get yourself some max lead 2000 additive. You can locate venders over at the NCRS board for it.
(3)Where I'm at now... Sunoco ultra thats it, runs great. However, I did block the heat crossover the last time I replaced the intake gaskets. That blocking of the heat under the carb cured any pinging I may have had. Downside is it takes longer to warm the choke.
BTW... I run 12 dgrees vacuum advance, blocked the TCS.
(1)You can use aviation fuel if you have access. My 70 L-46 runs best on that.
(2)Next best thing... get yourself some max lead 2000 additive. You can locate venders over at the NCRS board for it.
(3)Where I'm at now... Sunoco ultra thats it, runs great. However, I did block the heat crossover the last time I replaced the intake gaskets. That blocking of the heat under the carb cured any pinging I may have had. Downside is it takes longer to warm the choke.
BTW... I run 12 dgrees vacuum advance, blocked the TCS.
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Drifting
Joined: Sep 1999
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Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
[QUOTE
It's a '70 L46 Laguna Gray Metallic / Black coupe. The VIN is 194370s413558. Other than a T&T steering wheel (N37,) the only options are performance options: L46, M21 & ZQ9.QUOTE]
To lazy to look it up whats ZQ9?
It's a '70 L46 Laguna Gray Metallic / Black coupe. The VIN is 194370s413558. Other than a T&T steering wheel (N37,) the only options are performance options: L46, M21 & ZQ9.QUOTE]
To lazy to look it up whats ZQ9?
Safety Car
Joined: May 2003
Posts: 3,814
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From: Dearborn Heights Michigan
I run Sunoco 94 unleaded in my 70 L46 with no lead additive. Not necessary to add the lead. Was running 110 leaded mixed with regular but at $6.00 a gallon and my gas mileage. forget it.
Thread Starter
Drifting
Joined: Feb 2000
Posts: 1,591
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From: Central MN
The car passed inspection so it's a "Done Deal." The inspector specializes in Corvettes and all the numbers match. Appearance is excellent and other than the engine temp. gauge not working (a cracked sending unit wire) the car is in perfect mechanical condition (even the clock works.) Obviously, the car is 37 years old and as such (being bone stock and un-restored) the paint has a few rock chips. Delivery should be mid July. I'll take some pictures and post them on the forum.
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Joined: Oct 2004
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From: Cape Cod, Mass.
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Nice looking coupe 
Good luck with it
Good luck with it
Melting Slicks
Joined: Jun 2004
Posts: 2,077
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From: westmoreland N.H.
you can always go to your local airport ,and get 100lowlead avgas. add one gallon to a fillup. gets you the octain you need with a bit of lead for lubrication. this is what i did for my L-46. works great...
