We have found that the lowest resistance can be had with a BOSCH SUPER PLUS 7907 however it is listed as a Yugoslavian plug WR9DC. These low resistance high output plugs will come pre-gapped at .023 however they will need to be opened up to .032 in order to get the best idle and performance. These plugs measured at a STABLE 4.7k ohms resistance.
1986-1991 Mercedes-Benz 420 V8 M116 Engines- BOSCH SUPER SPARK PLUG #7905 @ .032 gap O.E. 6k + Ohm Resistor
1986-1991 Mercedes-Benz 560 V8 M117 Engines- BOSCH SUPER SPARK PLUG #7911 @ .032 gap O.E. 6K + Ohm Resistor
1986-1991 Mercedes-Benz 420 & 560 Low Resistance M117 and M116 BOSCH SUPER SPARK PLUG #7607 @ .035 gap with 4.7K Ohm Resistor
We now offer an entire low resistance BOSCH tune-up kit for sale on 1986-1991 Mercedes-Benz 420 and 560 V8 vehicles.
This is our stock photo-
This kit will retail for $340.00 complete and include free shipping in the USA. We have a sale going on E-bay right now seach "Mercedes-Benz Tune Up" and you should be able to see it. We will have a link up shortly to our own web site and it will take Visa - Master Card and PayPal.
Thats a lot of good stuff for a fair price! Plus it includes support, an oil filter, plug gapper and everything needed to save yourself another $300-400 on labor! Thats close to a $500 savings plus you know the job is done right once you have done it for yourself!
-- Edited by Administrator at 07:40, 2007-11-11
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What is to give light must endure burning -- Viktor Frankl