Unleaded Valve Recession

[Peter & Penny Stanisavljevich]

Okay, it’s been 20 years since leaded gasoline’s last hurrah in the US. To date I have not seen or heard of a single engine suffering valve seat recession as the result of running unleaded.

My personal feeling is that is was an urban myth. Anyone have any personal experience?

[James & Susan Ellis]

Cannot say about the Ford V8 heads but I have beat the seats out of a couple Alpine heads. Not sure this was due to the lack of lead or me running the snot out of them.

[Eric and Bonnie and Bonnie Gibeaut]

Ahhhh Jim-I have seen you drive your Alpine…..redline? What redline?!
Look out new V-6 engine!! Eric

[James & Susan Ellis]

I put a rev-limiter on it for a reason…..

[sunbeam74]

Jim,

I have seen you run the old gray mare…
I have to ask, just because the answer might leave us chuckling, what limit do you have your car set at? 🙂

Steve

[James & Susan Ellis]

Now Steve why would that make you chuckle?

6400 was where I set it for kicking butt but day to day 5600

Disclaimer……. Robert I never got the engine broken in so it did not see those revs. You guys are going to give him a heart attack.

[James & Susan Ellis]

That is normal right? right?

that ain’t stock…

[alpine-64]

Apparently VSR becomes an issue above 3000rpm. Alpine heads have hardened seats in them, but if they are original spec they will probably not stand up over prolonged use. I would fit hardened (modern spec) seats if you are doing a head and look at high quality valves SS if the budget allows.

[stu]

A friend in college had a Series 4 Alpine for transportation. I recall him having valve problems around ’68 or ’69, and saying that he had been running Amoco unleaded almost exclusively. He wasn’t a crazy driver, but did a lot of highway miles, Boston to NY and back. He had switched to a TR6 by ’70

Stu

[Robert and Mariet Jaarsma]

Jim, You saved me from that heart attack. When I heard about the abuse of an Alpine engine I wondered if it was mine? Thanks, I’mslowly nearing the point of installing it in the Venezia.
Robert

[v-mad]

So for the Tiger engine, are most guys running on unleaded without a lead substitute then?

[Gilles Blais]

I have put 14,000 miles in three years on an original 260 that came to me showing 34,000 miles on the clock. There were issues with the said clock and I would not be surprised if it had been disconnected for periods in the past: the dial was rebuilt but the cable not corrected so it was failing again when I got the car. This car has never been put away for any period beyond a yearly winterization.

Anyways… the car came to me with seeping original head gaskets so I had to remove the heads. The valve assembly was dismantled, the carbon cleaned out everywhere, the valve seats polished using the original valves. Everything looked ship shape, no pitting or surprises anywhere.

The car runs great with unleaded.

Cheers, Gilles

[v-mad]

Thanks Gilles, that’s reassuring to know.

Also, it’s good to hear of someone putting in some real miles, 14k in 3 years is good for a classic. But these engines can easily take it, they are so unstressed, unlike the little fours in many classic sportsters. In the UK though, the fuel is not cheap (nearly 1 GBP per litre!), so that tends to discourage high mileage. Whats the fuel cost like in Toronto?

[Gilles Blais]

Hi Chris,

Regular here has stabilized for now at around Cdn$0.90/liter. It was at around $0.74 a year ago. It had last peaked at $0.80 in August 2000. Premium is $0.10 more. I have never had any issues with Canadian gas. I have read many, on-going complaints about gas from UK members of another forum that deals with British motorcycles.

The pleasure of driving vaporizes for me when fuel cost becomes an irritant. I gladly got rid of a four-barrelled big block that ran on premium only when I got the Tiger. I find the Tiger to be very economical for the pleasure it gives, comparing well even with our two modern-day, computerized, family mobility appliances. It only makes 164 horses at full RPM! How much gas can it take given an efficient basic engine design that usually purrs at 1/3 power and a weight well below the magic 3,000 pound fuel mileage killer? I would think a lot less than it takes to move an Austin Healey or an E-Type, but I might be wrong.

Tigers and Alpines are good cars and they run better with use.

Cheers. Gilles

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