328 headlight relays - confused

The OEM Ferrari wiring diagram for my US Model Year 1989 328 shows that relays are in place for both the high and low beams. They are both Bosch relay number O 332 014 113. As you noted, the owners manual also shows them on the board with the fuses. Hope that helps - as you said, you already have relays...

 

Yes, your 328 already has relays for switching the headlamp bulb currents (i.e., the current in the headlight switch is already small and not the current that goes to the headlamp bulbs). Adding another relay physically closer to the bulbs might increase the voltage at the bulbs very slightly, but you'd lose the protection of the fuses in the current path going to the bulbs.

Do you really have a significant problem? Your stock set-up with H4 bulbs should already be way, way better than a US 308 using sealed beam headlights.

 

Mine too, 1989 MY. But much weaker headlamps when hooked up to stock vs. rewire with relays. I wired it up per Daniel Stern's website diagram for this upgrade, previously discussed in a few threads. www.danielsternlighting.com if needed. I think it might be the wiring, being a smaller wires, not sure. Didn't want to rewire from the fusebox, too involved so hooked up relays in near one of the lights.

Jeff

 

I'm using H4's with some Marchal lenses.

Sort of in line with the existing relays. I guess a jumper could be established for that one active wire. Much better performance so didn't really think about this until you brought it up. Got me thinking, I'm going to look more into this...

If you want to go real crazy, Mike328 did a HID upgrade on his 328.

Jeff

 

Not sure how your 328's are wired with this factory relay. However, the key to the relay retrofit is that the electricity to drive the headlights come directly from tbe battery and thus as NO voltage drop to get to the headlights (because it does not need to go through the switch, but also due to the smaller wire run and thicker wire). Unless the 328 set up has the headlights wired directly to the battery, and the switch merely triggers the relay that then allows the current to go directly to the headlights, it is not set up to accomplish the same uninterrupted voltage to the headlight as the relay retrofit.

I did a relay retrofit on a 1967 car and the difference was unbelievable. Modern level lighting on a 40 year old car. This is a retrofit I recommend to all vintage car owners. As to its effectiveness on newer cars, I don't know. My 87 328 has decent headlights without the retrofit and I've never really felt the need to change it. That said, reports on FChat are such that most who have done it on the 328 cars seem to think it is a significant improvement.

Alberto

 

As Mike said, US 328 have the same relay set-up your 328 has, but came with sealed beam bulbs.

US 308 do not have the relays (i.e., the high current passes thru the headlight switch contacts) and sealed beam bulbs (so these benefit most from the relay upgrade).

Jeff has a good point that the headlight wires aren't exactly massive on a stock 328, and there are a few connections in the current path (at the fuses and where the wires exit the PWB in the infamous white connectors) where you might be dropping some voltage. I guess it all depends on what you want -- personally, I thought using H4s on my stock-wired 308 were great, and more than good enough; however, they weren't anything close compared to today's ridiculous (and annoying to other drivers IMO) overly-bright systems.

 

Well put, exactly.

Jeff

 

AU CONTRAIRE -
By actual measurements, the relay modification increased voltage at my bulbs OVER 2 VOLTS !! And overcurrent protection is NOT comprimised as there are fuses at the battery.

AND -
While relay coils are operated by the headlight switch to actuate bucket motors and parking circuits, BOTH high and low beam current IS THROUGH THE SWITCH ! Headlight switches commonly defunctuate themselves in despiration of awesome agony.

This is a highly worthwhile modification.

 

My US MY'89 328 wiring pdf is showing three relays. One for each of light lift motor, headlight lo-beam and headlight hi-beam.

Think I'd be going through with my DMM and a good contact cleaner before I'd think about adding any more relays.

 

Thanks for bringing that factoid to my attention. I don't have a 328 schematic but sounds like if Ferrari added those relays on the 328, it has to be a worth mod on a 308.