Lead substitute additive -- necessary?

13305 Views 19 Replies 8 Participants Last post by hueterm, Apr 20, 2009

hueterm

Discussion Starter · Apr 18, 2009

1970 Grand Prix, 400 V8, pre-cat-convert...

I used to put lead substitute in it, 15-20 years ago when I drove it. It has pretty much sat since then.

Yea or Nay on whether or not it's necessary? Any recommendations on which one to use? I like the idea of the CD-2 super concentrate, in one bottle, instead of having all of the little bottles taking up space in the trunk...

1 - 20 of 20 Posts

77CDV

· #2 · Apr 18, 2009

If you're not driving it regularly long distances at high speed, substitute shouldn't be necessary. I'd be more worried about the effect of all the ethanol in modern gas on older fuel system components.

V-Eight

· #3 · Apr 18, 2009

77CDV said:
If you're not driving it regularly long distances at high speed, substitute shouldn't be necessary. I'd be more worried about the effect of all the ethanol in modern gas on older fuel system components.

Yep, goddamn renewable fuel......

hueterm

Discussion Starter · #4 · Apr 18, 2009

There are some stations in my area that don't use any ethanol. I'll have to track them down.

Is the effect of ethanol cumulative? Or will a tank now and then (since it only gets about 9 MPG, I may not be able to choose) not be too big of a deal?

MauiV

· #5 · Apr 18, 2009

Pics!!!!!!!!!

My first car was a 1975 GP, Black w/burgundy interior, soft vinyl half top, Crager S/S and air shocks for the proper rake.

Car was a BEAST. The doors weighed as much as a Civic.

hueterm

Discussion Starter · #6 · Apr 18, 2009 (Edited)

Similar in size, although my '77 was more similar to your '75 than the '70 is. The '70 is almost indistinguishable from the '69. The '71 and '72 were similar, but boattailed.

It's in pretty rough shape. Traditional '70s gold, tan interior, tan full vinyl roof. Has aftermarket sheepskin seat covers now. It's on its 2nd coat of paint, but wasn't the best paint job, nor the best body repair. If I can get it done for under $10K, I'll be happy......

But it was my first car (I took my driving test in it -- 9ish foot hood and all -- and I passed parallel parking), and my dad doesn't want it anymore. So I'll take a few years and get it fixed up a little at a time.

I'll post pics as I get things done and keep them in a profile album.

Oh, and it was smokin' fast...

EDIT: This isn't mine, but it's the same color combination...

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gdwriter

· #7 · Apr 18, 2009

I love the 1969-70 Grand Prix — another great example of John Z. DeLorean's brashness.

When I bought my '64 Impala in 1999, I would occasionally put in lead additive when filling up, but not all the time. I never really had a problem one way or the other as far as I know.

However, in the summer of 2000, Betty started to run badly, and a compression test showed one of the cylinders had very low compression. I decided to rebuild the engine at that point and tearing down the engine showed one of the valves (not sure if it was intake or exhaust) was pretty much worn out. I don't know if the lack of lead additive had anything to do with it or not.

When I had the engine rebuilt, I had hardened valve seals (or is it seats?) installed so there wouldn't be a problem running unleaded. And although the Betty's 327, with a 10.5:1 compression ratio, was supposed to required premium gas, I'm able to run 87 octane with no trouble. Good thing, since she only gets 13 MPG if I'm lucky.

hueterm

Discussion Starter · #8 · Apr 18, 2009

He did do a good job w/that one -- it must have been all the coke... ;-)

Yeah, those late '60s, pre-fuel/smog '70s designs were some of GMs best. Those GPs, pretty much any Riviera, early Toros, Eldos all screamed "get out of my way", but with flair.

I'm hoping to not have to do any major powertrain work.....that will make it a 5 year restoration instead of say 3...

Submariner409

· #9 · Apr 18, 2009

IF we don't install hardened valve seats in an Olds 455 marine head we always recommend Alemite CD2 lead substitute - it doesn't take much. BUT these engines run at some fearsome loads, so the threat of valve seat recession is very real.

As gdwriter posted, having a machine shop install hardened seats is a very good option for a street car. It's done hundreds of times every day in shops all across the U.S. Very common.

Actually, ethanol laced fuels are cleaner burning than the old tetraethyl lead gas, not sure about MTBE, but you have to burn a tad more E10 for the same "power" because there's not as much energy, in BTU's, in ethanol as in pure gas.

Have you seen that the EPA, backed by the Corn Lobby, is considering mandating a minimum of 15% ethanol in emissions states/counties ??? Know why ?? Because there's too much ethanol lying around, the corn lobby wants a piece of the action, the big money investors are screaming bloody murder to Congress that their investments are going sour because overall fuels consumption is down. (Drive less to save a buck and the Government will make sure you pay a penalty.........) Motor companies are testifying that their vehicles are built to operate on the E10 EPA requirement, and to shift to all E15 would void warranties. The EPA reply: "Tuff Muffins. Don't honor the warranty."

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hueterm

Discussion Starter · #10 · Apr 18, 2009

Wasn't E85 supposed to save us all? Why not make that? Maybe because no one wants it when your mileage gets cut in half.

72186

· #11 · Apr 18, 2009

E85 also disintegrates rubber in the fuel system (seals and such) so it's not very compatible with older cars. I'd also wouldn't want to run it in a car without EFI.

77CDV

· #12 · Apr 19, 2009

Don't you just love when the gov't knows what's best for you? It makes life so much easier.

Anyway, it's a bright, sunny day and the clocks are striking thirteen, so why complain?

hueterm

Discussion Starter · #13 · Apr 19, 2009

Rodya234 said:
E85 also disintegrates rubber in the fuel system (seals and such) so it's not very compatible with older cars. I'd also wouldn't want to run it in a car without EFI.

Oh, don't worry, I'm not -- I was just saying that we'd have less surplus ethanol to screw around w/upping the percentage regs, if people were buying the E85 like they were "supposed" to...

gdwriter

· #14 · Apr 19, 2009

hueterm said:
Yeah, those late '60s, pre-fuel/smog '70s designs were some of GMs best. Those GPs, pretty much any Riviera, early Toros, Eldos all screamed "get out of my way", but with flair.

:yeah:

GM was at the top of its game, especially in terms of styling through the 60s and even into the 70s. After years of bland, boring designs, it's great to see GM design making a resurgence. If the economy were in better shape, I think they'd be selling several models like hotcakes.

Eric Kahn

· #15 · Apr 19, 2009

the additive is not needed, just drive the car and in 50,000 miles or so take the heads off and have them install hardened valve seats in it and all will be good

hueterm

Discussion Starter · #16 · Apr 20, 2009

How much does the hardened valve seat job cost? Anything else I need to be aware of (like the ethanol content of today's gas) w/this old of a car?

gdwriter

· #17 · Apr 20, 2009

I paid a little over $800 in 2000 for an engine rebuild that included the hardened valve seats. A friend helped me (actually, he did 90% of the work, I just held things, cleaned parts and handed him wrenches for the most part), take the engine out and put it back in, so that price was just for the rebuild work.

Submariner409

· #18 · Apr 20, 2009

Installing hardened seats during a head overhaul (guides, valves, seals) is a minimal additional machining expense. Ask the machine shop if you even need to install them.

E10 runs perfectly well in an engine fuel system calibrated to run on tetraethyl lead or MTBE. Anything OVER E10 will require rejetting the carburetor and maybe some ignition curve work.

77CDV

· #19 · Apr 20, 2009

Also, if you live in a hot climate or at altitude, you need to use premium grade fuel and be especially aware of the EtOH content, as it makes carburated cars more prone to vapor lock. Don't ask me how I know this. It's rather embarrasing.

hueterm

Discussion Starter · #20 · Apr 20, 2009

LOL, I'm used to premium w/the other cars -- one more isn't going to kill me. I guess 92 octane will be sufficient......

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