fuel
Thread Starter
Drifting
Joined: Mar 2006
Posts: 1,253
Likes: 41
From: Delray Beach Florida
fuel
Hi i need help once more - I just purchased a 67 327 350hp...the engine (original)was rebuilt some time ago - but was not converted to use unleaded the owner says it runs fine on unleaded gas - i am concerned about engine damage down the road - should i start using lead additive -if so where and what brand do u suggest???
Thanx Csysman
csysman@roadrunner.com
Thanx Csysman
csysman@roadrunner.com
Drifting
Joined: Apr 2008
Posts: 1,540
Likes: 51
From: Lexington Park Maryland
Without getting into a bunch of details, I've been using lead substitues since my L79 was rebuilt in 1990. Never had hardened valve seats put in either. Not sure if I needed the lead substitute but I've used it for years and haven't had any valve related problems. Some will tell you that it's not necessary....., I'm not saying they're wrong I'm just saying what my experience has been. I use CD2 Lead Substitute (Walmart stocks it). 1/2 oz per 5 gallons of fuel. It's cheap, $10-$12 for a 16 oz bottle with an "idiot proof" squeeze dispenser......, do the math..... it's about 160+ gallons treated with the 16oz bottle.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
There's no evidence of any street driven Corvette having suffered valve damage due to lack of lead in the fuel. The engines cannot be run hard enough, hot enough, for long enough for the correct conditions to exist.
Motor homes, dump trucks, stationwagons pulling camp trailers, yes, Corvettes no.
Having said that, I keep a photograph of a bottle of additive in my garage and show it to the car once a year on it's birthday (July 5th). I've been doing this since the late 1980s and it works just fine with no engine problems to date. Can't be too cautious you know.
Motor homes, dump trucks, stationwagons pulling camp trailers, yes, Corvettes no.
Having said that, I keep a photograph of a bottle of additive in my garage and show it to the car once a year on it's birthday (July 5th). I've been doing this since the late 1980s and it works just fine with no engine problems to date. Can't be too cautious you know.
Race Director
Joined: Apr 2005
Posts: 11,265
Likes: 2,131
From: Bowling Green, Kentucky
Hi i need help once more - I just purchased a 67 327 350hp...the engine (original)was rebuilt some time ago - but was not converted to use unleaded the owner says it runs fine on unleaded gas - i am concerned about engine damage down the road - should i start using lead additive -if so where and what brand do u suggest???
Thanx Csysman
csysman@roadrunner.com
Thanx Csysman
csysman@roadrunner.com
I also have a 1967 Corvette 327/350 HP. Have owned 15 years. It operates fine on 93 octane unleaded. I wouldn't worry to much about the valve seat wear for an occasionally driven car.
That being said, I have also used Kemco Octane Supreme 130 on occasion. This is a mix of tetraethyl lead (with appropriate lead scavengers) in a toluene base. It WILL increase octane and provide real lead protection. However it is sold for "off road" use, and if you are not careful, the toluene may lift your paint if you spill any on the car. Go to http://www.kemcooil.com for more info if you want.
The Kemco product has been around for over 20 years and started as Stone Oil Lead Supreme 130. It is the real deal. Your decision.
Larry
Safety Car
Joined: Jun 2003
Posts: 3,596
Likes: 8
From: Grosse Ile MI
There's no evidence of any street driven Corvette having suffered valve damage due to lack of lead in the fuel. The engines cannot be run hard enough, hot enough, for long enough for the correct conditions to exist.
Motor homes, dump trucks, stationwagons pulling camp trailers, yes, Corvettes no.
Having said that, I keep a photograph of a bottle of additive in my garage and show it to the car once a year on it's birthday (July 5th). I've been doing this since the late 1980s and it works just fine with no engine problems to date. Can't be too cautious you know.
Motor homes, dump trucks, stationwagons pulling camp trailers, yes, Corvettes no.
Having said that, I keep a photograph of a bottle of additive in my garage and show it to the car once a year on it's birthday (July 5th). I've been doing this since the late 1980s and it works just fine with no engine problems to date. Can't be too cautious you know.
I've put 8K miles on my 327/365 without hardened seats, additives, (or photographs of additive bottles
) with no problems. Oil will be much more of a concern than fuel.
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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You don't need any additives or hardended valve seats. Unleaded 93 Octane is fine. Last rebuilt my 65 L79 22 years ago (68,000 miles) and it's still running fine. No valvetrain problems at all.
The only thing I've noticed since they transitioned exclusively to Unleaded fuel is that my spark plugs last alot longer.
The only thing I've noticed since they transitioned exclusively to Unleaded fuel is that my spark plugs last alot longer.
Melting Slicks
Joined: Jun 2006
Posts: 2,660
Likes: 7
From: DFW
While I don't drive the Corvette a lot each year, I've had no problems with my original heads, rebuilt in 1975, without hardened valve seats.
Premium unleaded.. no aditives used since around 1980..
Harry
Premium unleaded.. no aditives used since around 1980..
Harry
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Race Director
Joined: Apr 2005
Posts: 11,265
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From: Bowling Green, Kentucky
I used AMOCO premium myself for many, many, years without issue. However, I switched to Super Shell and/or Sunoco 260 at the advice of a South Chicago Plymouth mechanic who I became friends with and who was into S/S drag racing. He said the lead was better for the valves in my 1965 Plymouth 383 (Police Special package). Who really knows......but I was ALWAYS running WOT in that Plymouth. South Chicago Police records during the late 1960's will substantiate.
Larry