Question on solex air filter

[SLOroadster]

You have a rare filter. That was the optional "performance" version. Because it is, you may as well keep it for the coolness factor.

Will

[Gary Hudson]

AWESOME!!!

[spl310]

Rare? Optional performance version??

I kind of doubt that. A lot of the factory Solex aircleaners were the closed units. I believe that this was done to reduce the induction roar, but don't have anything to back that up. There are a tremendous number of the open element units in use. The guys that want to get performance do like them, but in reality they are not an optimal choice. That is proven by the fact that most of the guys that use them in performance applications somehow extend the mounting stud and put double filters on it to increase airflow. They look cool, but don't have that much flow capacity. Certainly not enough to feed the capacity of the carbs.

The early cars that were delivered with the Solex package from the factory ALL had the fully open unit. That is all of the 67s and the vast majority of the 68s (Canadian and other non-US market high windshield cars that came with the Solex package from the factory) had the fully open element. If you look in the Brooklands book of Datsun Roadster road tests, you can verify that. All of the Solex powered cars in there had the open unit.

I would keep the unit (unless you want to donate it to ME of course! ) but not for any coolness factor. I would keep it because it is the correct item for the car. (damn that purist in me is talking again!) I would also consider finding a permanent filter or some of the gauze type - not for a performance thing, but because the OEM filter elements will dry up one day and it would be nice to have something to keep the beast on the road. I once knew who made the permanent filters that Stan sold, but have since forgotten. I think that they may be an Aussie company. I stumbled across their web site once and was astonished to find the Roadsters listed.

[Gary Hudson]

Okay, so not awesome. You guys are such a good source of information. I've heard elsewhere (it may have been Stan) about stacking two filters.

If you or anyone else stumbles onto that site with the permanent filters again please post it. I'm sure I'm not the only one who is curious, and Stan didn't seem to think he was going to get any more of them.

Gary

[SLOroadster]

I was told that the open element ones were more rare than the other ones. I think the velocity stacks are longer on the open ones as well. I know they are a pain to remove the filter from them. (more so than the closed element ones.) Needless to say, I have seen far more of the closed ones than the open ones.

Will

[spl310]

Well, I don't know which is more rare, but I have owned 5 and a half solex aircleaners. Two and a half were the open element ones, one was the early closed unit (LOADS of holes), and two were the late units. I still have one early one and the early closed unit. One of the early units went to a restoration of a 67.5 2000, one of the late units went to a stroker project and the base of the open one went to someone that will restore it (still regret getting rid of it for some weird reason...)

The early ones did have a better velocity stack design inside. On removing the element, they all seem to be somewhat of a pain - be it the SU or any of the Solex versions.