Difference Between H4 & H5?
02-01-2002, 11:14 PM
#1
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Difference Between H4 & H5?
Can anyone 'splain the difference between the 8" H4 headlights and the 8" H5 ones?
H4 = ROW (euro) H5 = US?
What makes the H4's brighter than the H5's in this lens configuration?
Do the lenses look different? Part #, ID stampings, etc. ?
Is there a difference between a left one and a right one - such as lens facets, beam angle...?
I just bought a pair of what I am believing to be Euro 8" H4's, including the entire 'pod' assemblies, that I am going to use to retrofit the stock 7" headlights on my '79. These lights have the glass 'nipple' on the top edge.
I've been told that the entire light assembly will bolt up to the existing mounting points.
All thoughts, experiences and suggestions from Greg B and all others are appreciated.
H4 = ROW (euro) H5 = US?
What makes the H4's brighter than the H5's in this lens configuration?
Do the lenses look different? Part #, ID stampings, etc. ?
Is there a difference between a left one and a right one - such as lens facets, beam angle...?
I just bought a pair of what I am believing to be Euro 8" H4's, including the entire 'pod' assemblies, that I am going to use to retrofit the stock 7" headlights on my '79. These lights have the glass 'nipple' on the top edge.
I've been told that the entire light assembly will bolt up to the existing mounting points.
All thoughts, experiences and suggestions from Greg B and all others are appreciated.
02-01-2002, 11:49 PM
#2
Burning Brakes
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Randy, Check out Bill's web site. He just did this recently. Sounds a little too involved for me so I just bought the Plasma bulbs which showed some improvement.
<a href="http://www.billsworkshop.com/P928S4/h5toh4/h5toh4.htm" target="_blank">Bills</a>
<a href="http://www.billsworkshop.com/P928S4/h5toh4/h5toh4.htm" target="_blank">Bills</a>
02-03-2002, 01:51 AM
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Hi Randy--
There are a couple telltale signs that you have H-4's. The lens has a very distinctive pattern that includes what looks like a wedge pattern on the right quadrant. From horizontal to maybe thirty degrees, and very pronounced. This is the part that gives you the high right side light over what would otherwise be a flat-topped low beam pattern.
The H-4 bulbs take the same connector as the 7" DOT lamps you've enjoyed all these years. The H-5's have a waterproof boot, o-ring seals for moisture, and a D-shaped plug that fits into a recess in the back of the bulb itself. The spade pins are narrower, a little more than 1/8" wide vs 1/4" for the H-4's, and are parallel on the H-5, while the H-4 has two parallel and one across them at one end.
Left and right side H-4's are identical.
IIRC, the H-4 lamps do not have the three indexing tips on the face of the glass. H-5 and other US-spec lenses have these three tips so that suction-cup aiming devices can attach and index easily.
Both types have the little blob on top, so you can see if the bulb has failed while driving. No matter that it's dark in front of the car... ;-)
The real H-4's are a treat compared with DOT lamps. Downsides, and the reasons they were never approved for US highway use, include corrosion and other deterioration of the silvering in the reflector. The mirror surfaces will dull over time, significantly reducing light output. The H-5 bulbs have a definitely inferior beam pattern when new, but the bulb is enclosed in a separate glass envelope that's part of the reflector itself, making it a sealed beam with a replaceable bulb. Those o-rings on the connector make a waterproof seal at the connector, while o-rings aty the front of the bulb protect that envelope from contamination. Pretty well thought out, if only the beam pattern of the H-5 was as good as the H-4.
HTH!
There are a couple telltale signs that you have H-4's. The lens has a very distinctive pattern that includes what looks like a wedge pattern on the right quadrant. From horizontal to maybe thirty degrees, and very pronounced. This is the part that gives you the high right side light over what would otherwise be a flat-topped low beam pattern.
The H-4 bulbs take the same connector as the 7" DOT lamps you've enjoyed all these years. The H-5's have a waterproof boot, o-ring seals for moisture, and a D-shaped plug that fits into a recess in the back of the bulb itself. The spade pins are narrower, a little more than 1/8" wide vs 1/4" for the H-4's, and are parallel on the H-5, while the H-4 has two parallel and one across them at one end.
Left and right side H-4's are identical.
IIRC, the H-4 lamps do not have the three indexing tips on the face of the glass. H-5 and other US-spec lenses have these three tips so that suction-cup aiming devices can attach and index easily.
Both types have the little blob on top, so you can see if the bulb has failed while driving. No matter that it's dark in front of the car... ;-)
The real H-4's are a treat compared with DOT lamps. Downsides, and the reasons they were never approved for US highway use, include corrosion and other deterioration of the silvering in the reflector. The mirror surfaces will dull over time, significantly reducing light output. The H-5 bulbs have a definitely inferior beam pattern when new, but the bulb is enclosed in a separate glass envelope that's part of the reflector itself, making it a sealed beam with a replaceable bulb. Those o-rings on the connector make a waterproof seal at the connector, while o-rings aty the front of the bulb protect that envelope from contamination. Pretty well thought out, if only the beam pattern of the H-5 was as good as the H-4.
HTH!
02-03-2002, 05:04 PM
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Thanks Bob. A discussion with Greg Byron yesterday also confirmed that I do have H5's, as opposed to the H4's as represented by the seller.
They are in very good condition and I have decided to install them anyway. Greg had indicated that the lighting improvement of the H5's compared to the OEM sealed beams is vast, and the additional improvement by the H4's compared to the H5's is not incrementally significant. So, I wanted H4's but have settled for these nice H5's.
Hmmm, now I'm wondering if I should try a pair of those faux xenon H5 bulbs. Anyone have thoughts one those?
They are in very good condition and I have decided to install them anyway. Greg had indicated that the lighting improvement of the H5's compared to the OEM sealed beams is vast, and the additional improvement by the H4's compared to the H5's is not incrementally significant. So, I wanted H4's but have settled for these nice H5's.
Hmmm, now I'm wondering if I should try a pair of those faux xenon H5 bulbs. Anyone have thoughts one those?
02-03-2002, 05:20 PM
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Color temperature is the issue, and depends on which "xenon" gas is used. Most that I've seen have a higher temp, trimming the red component and accentuating the blue. Not any more usable light, and in the cheap ones that just have blue glass envelopes, actually there is less.
Most are "look-at-me" bulbs, trying to convince the unknowing that you hev the expensive 25w HID package. No benefit from extra usable light for the driver.
In the meanwhile, I put in 80w/100w 9004 (H-5) bulbs for a noticeable improvement. Still plenty of red in there so the color is what you are already used to. Lots of places sell these; I got half a dozen from Whitney, and promptly went through half of them in the Explorer before changing back to standard 9004's. Hmmmm-- must be the 14.8 volt system in that car. The 928 has only eaten one of them so far, with 13.7 volts system. So I have one spare in the glovebox in case an installed one bites the dust on me. I think DR lists the brighter bulbs on his website if you can't find them elsewhere. He also has hi-wattage super whites or something like that. I'd ask his opinion on them too.
Oh--- the hi-wattage bulbs like to melt the sockets. Gone through enough that I have a couple spare sockets set up with bullet connectors just in case. Sockets came from Pep Boys, by the way, but the same ones are also at some Kragen stores if you look.
Most are "look-at-me" bulbs, trying to convince the unknowing that you hev the expensive 25w HID package. No benefit from extra usable light for the driver.
In the meanwhile, I put in 80w/100w 9004 (H-5) bulbs for a noticeable improvement. Still plenty of red in there so the color is what you are already used to. Lots of places sell these; I got half a dozen from Whitney, and promptly went through half of them in the Explorer before changing back to standard 9004's. Hmmmm-- must be the 14.8 volt system in that car. The 928 has only eaten one of them so far, with 13.7 volts system. So I have one spare in the glovebox in case an installed one bites the dust on me. I think DR lists the brighter bulbs on his website if you can't find them elsewhere. He also has hi-wattage super whites or something like that. I'd ask his opinion on them too.
Oh--- the hi-wattage bulbs like to melt the sockets. Gone through enough that I have a couple spare sockets set up with bullet connectors just in case. Sockets came from Pep Boys, by the way, but the same ones are also at some Kragen stores if you look.
