Having studied carefully the diagrams and specifications of H8, H9 and H11 bulbs, I suspect that their bases (PGJ19-1, PGJ19-5 and PGJ19-2) are very very similar and perhaps one could be substituted for another with little or no modifications. Has anybody already tried doing this?

To be more specific, I am interested in replacing H11 bulbs with H9s. The lamps have glare shields, so the fact that H9 bulbs do not have a cap should not be a problem. Any info would be apprieciated!


P.S. On a similar note, would it be easy to modify an H7 lamp to accept H9 bulbs? Thx in advance.

Have u studied H7/H9/H11 Osrams datasheet (linked from faq liks page ( http://faq.auto.light.tripod.com/links.htm ):

http://www.osram.se/pdf/produktblad/H7H11.pdf

Let us know what u find out.

Thanks for the link, Herman. Part of that document appeared as an article in Osram's Automotive Spot 4/98. Interestingly enough, the 2003-2004 Automotive Catalog (found on the same site) provided even more significant evidence that all PGJ19-? bases are identical:

http://www.osram.se/pdf/produktblad/AMKatalog_20032004

Weird, this document is not available in the osram.com website! You might want to include it in the Automotive FAQ links, since it is VERY comprehensive.

Anyway, now that there is sufficient (theoretical) evidence to support my claim, I intend to buy a couple of H9 bulbs and verify whether they fit in H11 sockets myself.

I have a pair of brand new H9s from Hella 90mm, wanna buy them?

That would be fine by me. However, shipping costs could be overwhelming (I live in Greece)... Do you still think it's worth the trouble?

That is quite a distance, shipping cost will probably be higher than the bulbs themselves. Oh well, good luck then.