Hi all, Been a while since I've posted. I have a question. I ordered 8 new spark plug lead extensions for my 328. The new ones are much shorter than the originals?? I questioned the vendor and he assured me these are the correct ones? The only issue I can see is when seating them in the valve cover I really have to press down on the red plug cover to get them to seat properly. My fear is, since there's upward pressure now, will they work loose? Anyone else installed these on their car? Thanks, Image Unavailable, Please Login Image Unavailable, Please Login
Did you look inside ? maybe the new ones you need the round nut on the spark plug and the old without it ?
The 328 extenders are different from the earlier QV 3 litre engines (and the earlier 2V injected engines are different again, they used a black version of the shorter 308 QV extenders. There are quite a few references here in earlier threads, I went through them last fall when I was building new plug wires for my XDI-converted 308 QV. From the Ferrariparts.co.uk catalog, Diagram 42 - Ignition, part number 126699 is the correct 328 extender - notice the 3 flats below the top connector, like your old extender in your picture above, and they're 107 mm length. https://www.ferrariparts.co.uk/part/ferrari/126699 Image Unavailable, Please Login If you compare to the 3.0 2V extenders like on the 308 GTBi/GTSi, diagram 37 Ignition, part number 116613 looks like the part you received - no flats on the top of the extender insulator, and as you've found, the length is different as well - 100 mm. https://www.ferrariparts.co.uk/part/ferrari/116613 Image Unavailable, Please Login You want 126699, watch for the 3 flats on the top of the insulator part of the extender. AW Italian shows both of these parts as listed for the correct models, mentions the different lengths. https://www.awitalian.com/product/spark-plug-extension-red-107-mm-long-126699.html/ https://www.awitalian.com/product/spark-plug-extension-red-100-mm-long-fits-4-valve-euro-cars-only-116613.html/ There's also a black version of the 100mm long version, part number 115647 - https://www.awitalian.com/product/spark-plug-extension-black-100-mm-long-115647.html/. No matter, for the 328 you definitely want the 107mm long red extender part number 126699. Your vendor sent you the wrong versions. Cheers, Gordon
Thanks, I have an '81, 308 GTBi and you're correct, the extenders are black and shorter. The vendor responded that these are the "correct" extenders for a 328 and recommended I pull the wires through the red circular plug caps???? Doesn't seem right nor does it seem possible to pull the connection out of the red circular cap. .
Was my understanding that there were only two types of plug extenders. Black for early 308 Carb/injection and the red extenders for QV/328. I don’t think there’s enough of a length difference in the old red extenders versus the new red extenders to cause an issue. On a positive note the shorter extenders will keep the rubber boots seated snuggly around the openings in the cam covers. 2cts.
Would you mind naming the vendor? As I posted, there are definitely different part numbers for the 328 extender, and the extenders that vendor is insisting are OK are the 308 shorter version with a different part number. No question, the vendor is wrong. If their suggestion was to make the shorter extenders fit by pulling the wire through the cap, that's... downright dumb. It is possible to pull out or push through the wires through the cap, but the right angle connector on the wire that seats in the cap wouldn't fit on the extender if it was pulled through. I re-used the cap and pulled wires through to make one piece plug wires for my XDI installation Here's the wire pulled through the cap, Hemi rigid tube in place seated in the underside of the cap, wire with straight connector, the red spark plug boot fits inside the black tube: Image Unavailable, Please Login Old boot, extender, plug on the left; new setup with re-used boot, hard tube, soft boot, on the right Image Unavailable, Please Login One piece when assembled, from wire/boot/hard tube/soft boot clipped directly on top of spark plug. Eliminated the troublesome Magnetti Marelli extenders entirely. (Eliminated the distributors, too, and the failing Digiplex control boxes. I highly recommend the Electromotive XDI kit as sold by Nicks Forza Ferrari) Image Unavailable, Please Login Image Unavailable, Please Login
Gordon, WHERE did you get that cam cover cap in the last photo? Oh, and back on topic, IIRC the internal resistance of at least the black (2V) and like-sized red (QV) extenders is different too. The resistance MIGHT be different between the red QV and red 328 extenders yet again. IDK.
The distributor end cap was supplied by Nick’s Forza Ferrari as an option on his XDI ignition kit. I read a bunch about the various extenders last fall when I was preparing to install the XDI, and while there are quite a few assumptions that there are differences in resistances, any threads where actual measurements were made to compare, nobody found an actual difference, they all measured the same.
Gordon, Thanx. Question as I don't have a parts book handy. Did the exhaust cam pictured originally have a pullie on it for the air-pump that feeds the air injectors on the exhaust side?
Hi Mark, No, no air pump or pulley on this car - it's a Euro QV, so did not have the air injection system at all. Cheers, Gordon
