KH model petrol ?

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KH model petrol ?

Postby PeterB » Tue Jan 21, 2020 2:53 pm

Hello,
slowly I come to the technical work / details by restauration. Which typ of petrol is ok for a KH model ? Here in Germany I can take normal petrol 95 okt or super with 97 oct.......what is necessary ?
Thanks
kind regards
Peter
Last edited by PeterB on Tue Jan 21, 2020 3:05 pm, edited 1 time in total.
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Re: KH model

Postby panic » Tue Jan 21, 2020 3:05 pm

A stock KH does not require premium fuel, regular gasoline is sufficient.
However, over the years many of these (and K) engines have been rebuilt using 45 (WL, G etc.) pistons (which have the same bore size and pin diameter) due to scarcity of actual -52 pistons or bad advice.
An engine assembled with these pistons will have a lower static compression ratio due to much lower dome height (frequently anticipated) but also is now far more knock sensitive due to very large piston to head quench clearance at TDC, and will knock even on light throttle.
Do you know if your engine has the correct pistons? A real K piston always rises above the cylinder deck @ TDC, a 45 piston never does.
[url="http://victorylibrary.com/L-BK.htm"]The Linkert Book[/url]
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Re: KH model petrol ?

Postby Lisa » Tue Jan 21, 2020 3:20 pm

The higher the oct the cleaner the burn in my opinion use super I do the cleaner your oil will stay and less sludge will build up over time. Different strokes for different folks. High oct for me only done deal. The cleaner the interior the less wear over time. Oct drops over time when stored. For over 50 years I ran my 49 Pan on super only and stored it over the winter months in Mass. with NO additives added and never had a problem starting in the spring. Just saying.
Last edited by Lisa on Tue Jan 21, 2020 4:11 pm, edited 1 time in total.
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Re: KH model petrol ?

Postby hennesse » Tue Jan 21, 2020 3:40 pm

I believe that in Germany, the "octane" is advertised using the RON - Research Octane, while in the United States it is advertised using (RON + MON) / 2. So German 95 octane is about U.S. 90 octane. Our "mid-grade" gas is typically 89 or 90 octane.

These low-compression engines should not need more than 92 German / 87 U.S. octane, called "Regular" in the U. S. My KH runs fine on regular, although I often add some Mid-Grade. Try a tank of 95 German, then a tank of 92. If you don't notice any difference, stay with the 92.
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Re: KH model petrol ?

Postby EKHKHK56 » Tue Jan 21, 2020 3:56 pm

Regular fuel makes more bang for the buck, run it in any vehicle you can. Premium fuel is only needed for high compression/performance engines. Its like stale, less explosive regular fuel. It only makes more power in some engines by allowing more spark advance. Like the HO305 T/A motor in my 1975 K30 Truck. My 1999 Blazer w HP 4.3 runs great on Regular. Any pinging is controlled by computer. Regular=MorePower for engines around or under 8.5 to 1 compression.
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Re: KH model petrol ?

Postby 55panman » Tue Jan 21, 2020 4:41 pm

I picked up almost 5 miles per hour at the Bonneville salt flats with my 1955 Panhead vintage racer by going down from the 105 to the lower octane gas off the fuel truck. I'm running 11.5 compression in my Pan. Of course the higher altitude and high temperatures have their effect also.
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Re: KH model petrol ?

Postby panic » Tue Jan 21, 2020 4:57 pm

Premium refers to anti-knock rating, not detergent content.
[url="http://victorylibrary.com/L-BK.htm"]The Linkert Book[/url]
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