What fuel and and/or additives do people use?

Hello Rich...

In my K, I run Shell premium always.. Now and then I will add some octane booster.

Mike

 

What year is your Khamsin?
How quickly did the engine start pinging after using lead additive?

Ivan's website has a PDF copy of the Khamsin Owner's Manual to which you can refer. I skimmed it but didn't see a fuel recommendation, perhaps you can with more time at your disposal. Here is a link: http://www.thecarnut.com/Manuals/MUM_KhamsinAm120.pdf

I did a brief online search and found a statement that Maserati built their engines for unleaded fuel starting in the "early seventies", which isn't very useful. (Italy didn't mandate unleaded fuel until January 1992, I believe. Some Italian-market-only Maserati's, like the Bi-Turbo 24v can't tolerate unleaded gas. Some exported Bi-Turbos ended up with burnt valves when new owners ran them on unleaded. I don't know if Maserati made "domestic-market-only" Khamsins.)

Just a brief anecdote regarding lead content and pinging:
Years ago I began using low-lead 100 octane aviation fuel in a 9.3:1 compression American V8 engine and it developed significant pinging after about 1,500 miles. Talking with the fuel supplier revealed that "low lead" aviation fuel had a far higher lead content than old fashioned leaded auto gas. I removed the cylinder heads and found deposits in my combustion chambers. There had become "hot spots" leading in my estimation to the pre-detonation "pinging". I cleaned the heads, switched to unleaded 93 octane with no pinging. It's been run that way for 10 years now. I recently switched all my classic cars to ethanol-free 91 octane gas, without lead additive.

It'll be interesting to hear others' comments on lead additive.

Best,
- Art

 

Art,

How can I put this gently ... your "research" on Biturbos is so far off well ...

None of those cars had any issues with unleaded fuel regardless of the the market destination.

My 84 has 70K miles and is as new in the engine department.

I never used any additives on my Bora and neither has any other vintage owner of a vintage Maserati whom I've known in this country.

Everyone should just stop worrying about this as an issue. Especially when considering how little and gently most are driven now.

 

Thanks for pointing out erroneous claims Bob,
The "Bi-Turbo info" was lifted from another Maserati site and I'll let them take the blame for the errors. In the meantime I'll try to edit my prior post to delete the claim of unleaded fuel melting valves.
Best, - Art

PS - Nope, can't edit the previous post.

 

Was that Maserati Get A Life?

 

Related to this subject, are people using 98 unleaded, or 95 (in the US that would be 93, or 91 Octane)?

The QP3 manual states that one should use 98 (93) unleaded, which I've done since I acquired the car.

Unfortunately, in the last 6 months over half of the stations around here have stopped selling 98 altogether, and more appear to be considering it.

I've read a little about octane boosters, from the articles I've seen, most of them don't seem to provide any real boost at all, and I'm not sure which if any are available here (Europe).

Could the 4.9l V8 be "retuned" to run correctly on 95 (91) octane? The few times I haven't had any alternative, the engine ran rougher, and I got poorer milage compared to 98 (93).

Do the older V8 cars also call for 98, or are they set up to run on 95? I.e. the Bora, Khamsin, Mexico and Ghibli.

Thoughts?

 

If you're having pre-ignition issues after a thorough tune up you might consider retarding the timing a bit. Have you distributor checked out too.

 

Hi Rich,

Been running mine on a mix of 95 and 98, but like you I stick with Shell fuels as my 4200 is supposed to have the better stuff so I take all cars to the same place. (makes life easier)

I've never used any additives as the previous owner hadn't. There'd been much debate in the Maserati club UK prior to me joining. Most folk agree with Bob's statement.

Bal

 

So 98 and 95 are both good? No differences in using the one or the other?

 

I use and will always continue to use high octane low lead aviation fuel in my cars that need a higher octane fuel rating. Or I use 112 or 116 octane racing fuels. It's $85 for a 5 gallon can. I mix it 1:5 and notice a total difference in how my engines run.

In regards to "higher lead levels" creating pinging and making deposits,.....sounds like improper ignition set-up and timing leading to pre-ignition more than improper fuel and too much "lead".

I also add Marvel Mystery Oil to my fuel and oil regularly. It never hurts to lube the valve train and the guts!!

.02 Lira

 

What site is THAT??

No, it was this enthusiast-maintained UK site, quite a while back. The discussion thread is on Page 75.

Enrico's Maserati Page

- Art

 

That one is from some time ago. None of what Miguel is claiming has been validated by any other stories but my god that engine did get hammered to death! I wonder who the idiot was who drove it like that for so long?

I own both a 24V and an 18V Biturbo engined car. The 18V is a lot easier to deal with but the performance is not as great. My 24V car is a Ghibli Open Cup factory race car so it doesn't get driven much but it gets hammered hard. That guy had a lot wrong with his car and continued to drive it anyway.

Enrico runs a great website.

 

Hi,

As Bob says with the kind of mileages done these days it's not easy to note any difference. I mostly use 98 but in the UK ethanol is creeping in in low doses, higher in France when I went to K40. You may notice differences in MPG with miles, but lets face it these cars are not going win prises on economy. from memory I think the best I saw was around 18mpg on the K40 run. But my calculations were hindered a bit until we realised that the odometer was reading too fast. Strange as the speedo was more accurate when compared with Sat Nav. I worked out that the error means that the car has done quite a bit less miles than shown on the dial.

I had the car on a rolling road last year to have it set up properly (most issues down to ignition) and I believe it was full of 95 at that point.

4200 was definately recommended to be run on 98 when I brought it from Maranellos in Egham.

Bal

 

The ethanol content wreaked havoc with the tune on my Espada. I couldn't get rid of the hesitation with the stock jets. I had to fatten the idle jets and the accelerator pump bleed off jets to get it to run "better". My 84 Biturbo was unaffected in that the carburetion remains smooth but I do think it has less power.

But I did a mileage and performance test on my supercharged Jar S-Type R with a tank of ethanol free gas and the results were dramatic.

But this has nothing to do with the octane rating and I can't realistically buy ethanol free gas here.

 

Hi Bob,

You are exactly right, ethanol wreaks havoc on carburetors and injectors where the metering of fuel function is so important.

For daily drivers, ethanol fuel can be used with success. Otherwise when given periods of inactivity/non-use, ethanol fuels will turn gummy causing as cascade of fuel metering malfunctions.

Additionally, I was told by a long time gas station owner that left unused, ethanol fuels will seperate out with water being one of the components. This in turn causes internal rusting of the fuel tanks if they have never been re-lined. One might need to check with a chemist to validate that claim, however.

For drivers here in the States there is a link for all ethanol-free fuel gas stations. U.S. octane rating has in my experience always been 91 for ethanol-free fuel. You can find this link on the Merak Group website under the "Links of Interest" tab.

I may need to track down a European equivalent website for ethanol-free fuel, as that would be a good addition to the site.

Ciao,
George

 

We have 93 octane premium in Texas where elevations are pretty low except for the panhandle. US labeling is the average of the Research and Motor octane ratings. Since the MON is typically 8-10 points lower than the RON, 93 here corresponds roughly to 98 in Europe where the RON is used on the pump.

Also, for the non-US, non-UK readers, the Imperial gallon is almost exactly 20% larger than the US gallon. Bal's 18mpg would be almost 22mpg for us. I would be very happy if the Bora or QP3 got that mileage!

 

Dang - got that backwards. It would be 15.. sounds more like it.

 

Charles claimed in the QP3 thread to get 12l/100km, or 19.6MPG in his QP3. Mine is nowhere near that, but we're doing some tuning and tweaking to see if we can at least get to 15l/100km (16mpg). That at least would get us in the ballpark with most modern big SUV's (BMW, Land Rover, Porsche, etc).

 

Ethanol free gas stations don't exist in NJ.
There aren't that many in PA.

Besides the issues with damage from ethanol, of which I have not suffered as yet there is the issue of having to re-jet the carbs and a loss of MPG both of which are very real.

 

By George, you're right!

Is getting fuel from a local county or city airport an option?

Just Wunderin.

Ciao,
George

 

Be careful with aviation gas. Even the "Low Lead" 100 octane for piston aircraft engines contains more lead than automotive gas ever had. I got deposits and detonation within 2,500 miles and had to remove my heads for a cleaning. I haven't used avgas since.

Here is a website of US & Canadian locations with ethanol-free automotive gas: Ethanol-free gas stations in the U.S. and Canada

Best, - Art