Bosch vs Hella
07-03-2011, 10:14 AM
#16
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If you buy used 8" H4 lamps, be CERTAIN that they are from a right-hand drive country - i.e., not the UK, Japan, etc. Using a left-hand drive bulb in the USA will have very bad results...
07-03-2011, 11:12 AM
#17
Captain Obvious
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The standard 8 inch light as fitted to 87-95 USA 928s is an H-5 and is NOT an H-4. All H-4 lights of all years and sizes are not DOT approved and therefore are illegal in the USA. Porsche designed the 928 to use an 8 inch light and Bosch was and is the ONLY one to make them. Euro spec cars got them, USA cars got fitted with 911 buckets and the 7 inch seal beams as used on a 1957 Chevy..... For the S-4 Porsche created the H-5 as 8 inch lights made by Bosch to look like an H-4 but has aiming **** on the lens and a much different light pattern to get it DOT approved. Also note that the H-4 lights for right hand drive applications are believed to have diffferent cutoff and focus patterns to avoid blinding oncoming traffic.
07-03-2011, 03:39 PM
#21
Burning Brakes
Van:
The first thing you need to do is determine whether the 8" Bosch headlights you bought are H4 or H5. If they came from a '87 or later car, they will be H5s - which are a step down (except in appearance) from the 7" Hella H4s that you already have.
The main difference is in the bulbs and connectors (plus lens design). If the 8" Bosch lamps use the same bulbs as your 7" Hellas, they are H4s (they should also say "H4" right in the center of the lens) and you're good - assuming they came from a left-hand drive car (Wally has it exactly backwards).
By the way, the 7" Hellas on your car are a common aftermarket upgrade - they plug right in using the same connectors as the sealed beams - which your car originally came with.
James
The first thing you need to do is determine whether the 8" Bosch headlights you bought are H4 or H5. If they came from a '87 or later car, they will be H5s - which are a step down (except in appearance) from the 7" Hella H4s that you already have.
The main difference is in the bulbs and connectors (plus lens design). If the 8" Bosch lamps use the same bulbs as your 7" Hellas, they are H4s (they should also say "H4" right in the center of the lens) and you're good - assuming they came from a left-hand drive car (Wally has it exactly backwards).
By the way, the 7" Hellas on your car are a common aftermarket upgrade - they plug right in using the same connectors as the sealed beams - which your car originally came with.
James
07-03-2011, 05:00 PM
#22
What does this mean? Does it mean that the connector is the same style, but the wires are arranged in a different order? I thought that they were the same and the sealed beams could be swapped out to upgrade to the H4's. Is this right or wrong...I'm getting confused.
07-03-2011, 05:32 PM
#23
Electron Wrangler
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The Pre S4 US cars had sealed beams that use a standard H4 (9003) connector (they are not H4 lamps despite this compatibility). Standard H4's from various sources are plug & play with these connectors. There are no pinout changes required.
USA S4 & GTS cars had H5 lights & H5 connectors (9004) these are not compatible with any H4's - converter connectors are available - but it probably better to cut off the H5's and replace with H4 connectors (cheap and widely available).
Alan
USA S4 & GTS cars had H5 lights & H5 connectors (9004) these are not compatible with any H4's - converter connectors are available - but it probably better to cut off the H5's and replace with H4 connectors (cheap and widely available).
Alan
07-04-2011, 01:05 PM
#24
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Thread Starter
Here a a few pic's of the 8" Bosch and what I had in the past.
The 8" are DOT lights with replaceable bulbs. What I have pulled out is a 7" H4 with 55/100w after market bulbs. What I am reading is that I have gone to a less powerful headlight in favor of fashion. I do think the 8" lights look better.
However this is not the "plug and play" replacement at I thought it would be. Note the differences
in the assembly and the newer lights seem to have the adjustment from inside the car option.
Also where the new assembly bolts into the bracket fork on the car the bolt pattern is different.
At first I thought I could just replace the old assembly with the newer one but this may not be the best
option.
Thoughts?
The 8" are DOT lights with replaceable bulbs. What I have pulled out is a 7" H4 with 55/100w after market bulbs. What I am reading is that I have gone to a less powerful headlight in favor of fashion. I do think the 8" lights look better.
However this is not the "plug and play" replacement at I thought it would be. Note the differences
in the assembly and the newer lights seem to have the adjustment from inside the car option.
Also where the new assembly bolts into the bracket fork on the car the bolt pattern is different.
At first I thought I could just replace the old assembly with the newer one but this may not be the best
option.
Thoughts?
07-04-2011, 01:19 PM
#25
Rennlist Member
The 8" H5's you are trying to install are DOT-legal and were the original lights for the later USA cars. They are marginally better than the 7" DOT-legal lights that came with your car, but (as explained many times above) they are NOT as good as the 7" H4's that you have, or the 8" H4's. You are trading cosmetics for function.
However this is not the "plug and play" replacement at I thought it would be. Note the differences
in the assembly and the newer lights seem to have the adjustment from inside the car option.
Also where the new assembly bolts into the bracket fork on the car the bolt pattern is different.
At first I thought I could just replace the old assembly with the newer one but this may not be the best
option.
Thoughts?
in the assembly and the newer lights seem to have the adjustment from inside the car option.
Also where the new assembly bolts into the bracket fork on the car the bolt pattern is different.
At first I thought I could just replace the old assembly with the newer one but this may not be the best
option.
Thoughts?
Your lights are missing a "hinge" assemble on either side, to mate the headlight frame to the "yoke" assembly. If they were supplied as 928 headlights, then they should have that as part of the light assembly.
07-04-2011, 01:52 PM
#26
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Also looks like the white plastic socket which the ball snaps into is broken (common problem).......so even if you had the hinges it might not work. Sorry but you got scammed !
07-04-2011, 01:54 PM
#27
The Pre S4 US cars had sealed beams that use a standard H4 (9003) connector (they are not H4 lamps despite this compatibility). Standard H4's from various sources are plug & play with these connectors. There are no pinout changes required.
USA S4 & GTS cars had H5 lights & H5 connectors (9004) these are not compatible with any H4's - converter connectors are available - but it probably better to cut off the H5's and replace with H4 connectors (cheap and widely available).
Alan
USA S4 & GTS cars had H5 lights & H5 connectors (9004) these are not compatible with any H4's - converter connectors are available - but it probably better to cut off the H5's and replace with H4 connectors (cheap and widely available).
Alan
07-04-2011, 02:29 PM
#28
Rennlist Member
Thread Starter
Thanks
I was the one that converted the sealed beams that came with my car to the Hella H-4 (7"). Also I changed out the bulbs to a brighter high beam. They work great, as I have done with other cars with round headlights for years including my old '73 911 (RIP)
What all of you are saying is that the 8" assemblies that I just forked out a bunch of cash, won't fit and if I want 8'' lights I should look for Hella 8" lights.
I was the one that converted the sealed beams that came with my car to the Hella H-4 (7"). Also I changed out the bulbs to a brighter high beam. They work great, as I have done with other cars with round headlights for years including my old '73 911 (RIP)
What all of you are saying is that the 8" assemblies that I just forked out a bunch of cash, won't fit and if I want 8'' lights I should look for Hella 8" lights.
07-04-2011, 03:00 PM
#29
Rennlist Member
Thread Starter
Bummer! I was really looking forward to installing 8" lights.
Good eye
One of the lights only has a 3 tabs left, the other is Ok. I was hoping I could switch out the frame the 8" sits in with the original 7" assembly. But it appears that there are enough differences so this won't work.
I will re pack them and put them on Ebay
Good eye
One of the lights only has a 3 tabs left, the other is Ok. I was hoping I could switch out the frame the 8" sits in with the original 7" assembly. But it appears that there are enough differences so this won't work.
I will re pack them and put them on Ebay