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Sun Mar 03, 2013 4:40 pm

The guy at Pep boys where I bought my plugs said the gap on NGK plugs is .024 as opposed to .028 on Bosch, which I am switching from. I thought that they should always be at .028. Any comments on this? 8)

Sun Mar 03, 2013 4:42 pm

The plug type is B6HS

Sun Mar 03, 2013 5:36 pm

0.028" please

Sun Mar 03, 2013 7:03 pm

.028 plugs with similar specifications from other manufacturers. Direct from the Bentley official service manual.

Sun Mar 03, 2013 8:03 pm

That's what I figured. Thanks :lol:

Sun Mar 03, 2013 8:10 pm

I thought I found something years ago, .024" was carbureted, but the EFI aircooled VW motors were .028".

Checking an old Bentley manual would tell.

Sun Mar 03, 2013 8:16 pm

I run .028" on all 12V. I'd consider .024 on 6V. With CDI I still run .028", I've seen too many problems with "big gaps", even with high powered secondary ignition.

Sun Mar 03, 2013 10:01 pm

VW Owner's Manuals have specified several gaps over the years, usually 0.024-0.028" but also recommending going as low as 0.016-0.020" in winter.

Mon Mar 04, 2013 8:07 am

What's the effect of changing the gap from .024 to .028?
Pros? Cons?
Are there any other adjustments that need to be made to the timing if you make such a change?
Tnx. Rev

Tue Mar 05, 2013 12:07 am

Mikedrevguy wrote: What's the effect of changing the gap from .024 to .028?
Pros? Cons?
This book: http://www.thesamba.com/vw/archives/books/chiltons49to71new.jpg Chilton's Repair & Tune-up Guide Volkswagen 1949 to 1971 says on page 28,
"The spark plugs in the Volkswagen should be gapped to between .024"and .028". In general, the best idling will result from a wide spaciing of the spark plug gap, but a wide gap will also cause starting to be slightly harder. A wide gap at high speeds will also lead to missing. On the other hand, a plug with a smaller gap will miss less at high speeds, give easier starting , but will cause poor idling. In order to improve starting ability when outside temperatures are very low, the plug gap may temporarily be reduced to .020". Because of the wide range of conditions under which the Volkswagen operates, it is probably best to gap plugs to the middle of .024"-.028" range, in other words .026".... The Volkswagen will operate equally well at any setting in the recommended range, and any differences would probably be so slight as to be unnoticeable."

EDIT:
Keep in mind that the information found in the Chilton book assumes that your engine has points and a stock coil. If you add a CDI or if you replace the points with Pertronix or Compufire and a 40,000+ volt coil then you may have better results with a different gap setting, though I'm not arguing with John @ aircooled.net who recommends sticking with .028".