head light bulbs , fuses , and wattage help !

[JR]

so i need a bit of info on this subject if you will , i have a mk2 ph1 so it has mk1 172 headlights on it . i am in the process of changing the bulbs for some blue tint ones that are higher in wattage ( 100w ) now the fuses for the main beam are 10A each ( one for each side ) when i put the new ( 100w ) bulbs in they blew both the fuses for the main beam so what i am asking is could i replace the 10A fuses with say 15A, or even 20A fuses without doing any damage/harm to any thing ?

many thanks

Justin.

 

[Da]

depends on the size of the wiring really. If it's got a 10A fuse then personally I would not increase the fuse size as you've more chance of melting the cables! 100w bulbs are not legal anyway as they are too bright (100w @ 12v is over 8A) If the bulbs aren't 'E' Approved then they are not street legal.

 

[Dink]

DO NOT PUT HIGHER RATING FUSES IN!!!

 

[V1NNY]

Dont use 100W rally bulbs either, get some Silverstar or vision plus bulbs or blue vision

 

[Da]

lol

 

[Djw John]

lol, nice and subtle Dink! But yeah a very valid point made. Im with Dink, Daz and Vinny on this one.

 

[Dink]

people don't realise theye are there for cable protection and not the equipment

 

[Da]

that's why they're at the source end and not the utilisation end

 

[Dink]

show off:rasp:

 

[JR]

ok so i will not put higher amp fuses in then , will have to see what happens when i put the bulbs back in after the fuses have been replaced with new 10A ones.

Justin.

 

[Dink]

yeah it might have been the in-rush current of the new lamps that operated the original fuses

but it they operate again ditch the 100w lamps

 

[JR]

did some calculations today ( ohms law ) and the 100w bulbs should be ok with a 10a fuse in as the lights need 8.8 ish amps , so we shall see. if it blows i will put the 65w ones back in.

 

[JR]

so i have just replaced the fuses with some new 10a ones and i put the 100w bulbs back in and it appears that my calculations were correct as they work nicely and have not blown, and they look much better and give better preformance than the philips blue vision bulbs i had before. thanks for all the help.

justin.

 

[Dink]

i got 8.3 amps @ 12v

and 9.72 amps @ 14 (without any extra correction factors for extra heat increasing filament temp)

so i'd guess you are border line

 

[Da]

same here Dink, seen as they're new fuses he should be ok for now
But 100w @ 14v is 7.14amps isn't it? :S

 

[JR]

yeh i think i am border line but i cam to this conclusion - if the fuses blow again i will put the old ones back in. ( if it does now torch my car first )

 

[Dink]

same here Dink, seen as they're new fuses he should be ok for now
But 100w @ 14v is 7.14amps isn't it? :S

they won't be 100w at 14 will they

 

[JR]

they won't be 100w at 14 will they

nope lol

 

[Da]

now who's showing off? lol!


:clown: