I've never found a lot of HP in ignition timing. You'll only go as far as 91 or 93 octane fuel will take you. Higher HP engines generally use an ignition "retard" feature for max top end HP.

could it simply be that this car has more mileage than your coupe or that the previous owner did not take good care. Same cars driven by diff people and in diff conditions end up driving diferntly at the end...
The SEL's were never that fast in pickup. The lexus LS400 have much better pickup try that sometime and you'll know what i mean. I've driven both so
good luck either way.

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Whether you think you can or cannot, Either way you're right!. by Henry Ford.

If the timing is wrong there is a lot of power to be found by setting it correctly.

Yes, having your timing retarded will generally reward you w/ better top end power..thus you use the ideal compromise seeing as these are street engines.

M117's (560's in particular) like 12-13 degrees initial timing as specified by the factory and even AMG seems to like that setting best. Take a US car to the dyno and pull the ignition resistor (giving you your full initial advance). If the rest of your engine is in proper running order you Will absolutely see HP gains. As for the 420 EZL, if I would be surprised if it runs more timing w/ the resistor pulled.. Next time I have a 420 in I’ll play w/ timing/resistors/EZL’s etc and see what I find.


As for comparing a lexus to an SEL, the lexus has a few advantages, one it automatically starts in first gear.. engaging first in our cars changes the character dramatically. 2nd, I wouldn't be in the least bit surprised if the lexus had a steeper diff..a Lexus was never designed to run all day @ 120+ so more aggressive gearing makes absolute sense.

As for how a car is driven, if you maintain a Mercedes properly the car will make good power for a long, long time.

Jonathan

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Blue Ridge Mercedes
Jonathan Hodgman
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Enthusiast Service, Restoration & Tuning.
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