Just refitting my dizzy to the V12 lucas 1984 after fitting a new vacuum control. Normal timing would be 10 btdc. Will 8 btdc be OK for E10 fuel?

 

There's no reason to retard timing and reduce power for E10. Use stock settings.

 

The actual spec is 18º@3000 rpm.

That may equate to 10º at idle; I dunno

Anyhow, as mentioned, there's no need to reduce timing simply because of E10 gasoline. You may want to reduce timing for lower octane gasoline.

Cheers
DD

 

Good catch on the timing spec. I will add that it is set with vacuum advance hose off and plugged.

 

I knew I had the info somewhere, I must stick my new emmision label on. 😀😀😀

 

Worth reading Grant's "Drive Timing" method in the stickies, Rex.

 

Here ya go Rex.

 

Thank you Grant..

 

Grant the adjusting screw on my car has never worked due to the little tag being broken off. Never caused a prob. But I did purchase a new one when I did the rebuild after finding the part no.

 

If anything you want to advance timing with ethanol. It has 114 octane. So you might be able to use 12 degrees
The British use RON ( Research Octane Number ) while America uses Motor Octane Number + Research Octane Number divided by 2
Instead of dealing with the math England sent us 11.5-1 compression pistons and used 12.5-1 compression pistons for themselves.

 

As rgp is over here in the UK, the absolute best thing to do for the car is to use zero ethanol petrol. There's no need to even have E5 petrol in the car as Esso's premium petrol has zero ethanol in 90% of the UK.. As with any classic car that covers low mileage and may be sitting for periods of time, I'd suggest they completely avoid ethanol even if only to minimise the risk of tank corrosion through ethanol's capacity to absorb water.

Cheers

Paul

 

Paul; It is in no way good for any car to sit for a long time unused. Not just problems with fuel but acid build up in oils and clogging or plugging up in the radiator. Besides that all gasoline has some water in it. . It collects in tanks both storage and gas tanks in cars.
Ethanol is a wonderful fuel that adds power ( INDY 500 cars use 100% NASCAR uses 15% drag racing, Land speed record setting moves cars using ethanol into faster classes . Helps the keep the inside of the engine clean. By eliminating typical carbon build up on the back side of the intake valve. ( remember our Jaguars are batch fired, leaving injection of the fuel air mixture up to the camshafts. So fuel without the cleaning power of alcohol will hit the back side of the intake valve and slowly Coke up. Finally through the cooling properties alcohol, engines run notably cooler
I understand you’re promoting 100% gasoline. E 5 & E10 represent 5&10% less business for you.
You’ll be shocked to hear that racers and hotrodders embrace E85. ( 85% ethanol 15% gas ) I use it instead of premium. Because with twin turbo chargers and 12 psi of boost I can take junkyard engines and make over 500 horsepower. Reliably.
Please don’t vilify your competition. While you might scare a few timid souls. Intelligent people will see right through you. Besides it’s bad form.

 

Mguar,

I do respect the obvious knowledge and expertise that you have on the use of ethanol as a performance fuel. It's just that for my cars and bikes, that are still running some of their original fuel lines etc, I really can't see any positives to putting any ethanol in the tank if I don't have to.

And I do agree that leaving a car sitting is not good. But the reality is that many classic cars get little use and are often laid up for some months in winter with salt on the road etc.. I guess it's the nature of classic car ownership.

I've got no intention to scare anyone and I'll happily learn from those more informed than I am. It's just that yours is the only voice I've heard that is advocating that ethanol is good for classic car ownership with all its foibles and realities of low mileage. . Certainly there's no-one in the car clubs over here that I've seen saying anything other than avoid it if you can. Hence my comments.

Perhaps it would be helpful if we had a specific thread on the use of ethanol in our Classic Cars? I'm sure we'd all benefit from in informed debate.

Cheers

Paul

 

Ethanol added to cars used on the street, E10, and especially those used only occasionally, is an abomination advocated and perpetrated by corn producers, propped up by politicians thru tax breaks and subsidies, in the US and elsewhere. It attracts moisture, causing fuel system issues, which is why boats use pure gas. Ethanol has far less energy than gasoline for a given quantity of fuel.

Yes, it is possible for E85 cars to make big power, taking advantage of higher effective compression ratios, especially for turbocharged cars. But on the street, E85 gets lousy fuel economy because of the low energy density. It also requires fuel system changes and adaption, to flow more fuel when E85 is used. In my area, it's gotten hard to even find E85, because no one wants to use it.

The EPA for years has required that all gasoline sold in the US, E10 or pure gas, have valve cleaning detergents, specifically to prevent valve carbon buildup. E10 does not change or help that. This came about in the 80s as fuel injected cars became more prevalent, well before E10 became prevalent.

Formula 1 still uses gasoline. For political reasons they started using some ethanol in their fuels this past season. As a result, they lost power, and had to go the extraordinary lengths to try to regain some of what they lost. They go for an entire race without refueling; let's see an Indy car do that.

For cars never designed to run E10, and especially for those only driven occasionally, E10 is a bad idea. It collects water, and deteriorates far quicker than pure gas. In high humidity environments, it deteriorates even faster.

And no, I do not work for an oil company, or in any part of the industry. But I am a degreed engineer, and have done my homework.

​​​​​​​Jon

 

It's been hashed over on these pages umpteen times.

There's no meaningful debate because everyone's experiences vary widely.

In my neck o'the woods E10 has been standard issue for over 20 years. Never had any problems at all using it in my 80s-90s Jags. I'm not surprised as even my 1985 owners manual say E10 is OK. Nor have I had any problems with my lawnmower, leaf blower, etc.

Others have had problems. Frankly, this disparity in experiences brings me to think are other possible variables at play besides with/without E10.

If you're gonna have a problem with E10 it'll occur during long periods of storage. And even that can depend on the ambient environment; how much moisture in the air, most importantly.

For long term storage the best bet, IMO, is aviation grade gasoline. It lasts much much longer than any pump grade gas, with or with ethanol.

Cheers
DD

 

Mguar
Paul is too polite to respond to the above unwarranted slurs. Please keep your comments polite; as the above are both inaccurate and rude. They are quite out of line with the happy and cooperative nature of this Forum - which I for one do not want to see altered.

 

The thread topic is IGNITION TIMING - not politics or the fuel used in various racing series which has little relevance to standard road cars.

Anyone wishing to bang those particular drums (again) should take it to OFF TOPIC.

Graham

 

Paul well said. I certainly agree regarding a alcohol heading
There are issues which even collectors who rarely use cars need to understand.
Corrosion will be found in the gas tanks of cars even those which use no alcohol. . Gas tanks need to be open to air. (Vented) If not they would form a vacuum and fuel couldn’t get to the engine.
Because they are open to air, any moisture ( humidity, rain) in the air will enter the gas tank and since gasoline is lighter than water sinks to the bottom of the fuel tank and cause corrosion.
If you own a car from the 30’s -50’s you may have a glass bowl in your fuel line. The purpose of that glass bowl was for you to detect any water in the gasoline and drain it out.
In Fact the very earliest gas pumps had glass display bowls ostensively for the same purpose.
First there are two alcohols commonly used as motor fuels. Ethanol and methanol.
Methanol gave alcohols a bad rap. Especially post WW2 . It’s cheap to make. From coal or even garbage . It was commonly found in gasoline to increase octane. Which it does. But it also attacks rubber, aluminum etc. if you drink Methanol. You die.
Ethanol doesn’t do that sort of thing. Ethanol is what beer, wine, scotch and Gin have. If you drink those you might get drunk if drank to excess.

 

For what it is worth, my US market 1983 HE is set to 20* BTDC at 3000 rpm with vacuum advance unplugged. This should correspond to about 12 degrees at idle. Mechanical and vacuum advances are operating normally. I run 89 pump octane fuel, usually sold as midgrade here in the US. I have never detected any audible detonation. I have not verified the timing tag against the piston at TDC but it does not appear to have been disturbed. I question if the engine requires as much octane as most people think it does.

 

If you drive gentle you could be right. But then why own a car like that at all? Don’t you want to push it enough to get the performance that was designed into it, out of it?
To me that’s like marrying a beautiful woman and keeping her barefoot and in sack cloth. Your opinion may vary.