re: 9004-vs-9007

[auditude <auditude@impulsedata.net>]

Chewy4000 <Chewy4000@aol.com> wrote:
> 
> What are the differences in these two bulbs?
> To me they look the same.
> Maybe different watage?
> 
> Chewy
> 89 200Tq (1 eyed, waiting for answer)

I didn't see a response, so I'll jump in here.

The difference is that the filament is oriented 
differently, for use with a different shadow mask 
(as I've heard it called).  One is longitudinal, 
and the other is transverse, so to speak.  I can't 
remember which is which.

The 9007's(?) will not fit your headlight without 
minor modifications.

Tony Lum posted a description of the mods, here it is:

> Try switching to 9007 bulbs-their filaments line up better with the
> interior shadow mask.  You'll have to use a hand grinder to make new
> grooves in the bulb base and I think you have to reverse the center and
> left wires (looking from the rear of the bulb-the wires inside the
> connector can be removed and switched).  You should also wire in relays
> (with adequate fusing) running direct from alternator.  This will be good
> for a additional 15% power and take stress off the lighting switch.  Once
> the relays are in, you can go up to 80 or even 100W low beams.  Should cost
> less than $40.  If that's not enough you'll have to add driving lights.

HTH,

Ken

P.S.  How does $80 sound to weld up my cracking firewall?  Reasonable?