Are all nikki carb spacers on 78-85 rx7's the same or are the early SA ones different?

I'm putting an SA intake manifold on my 85 engine, but don't have the spacer from the SA, just the one from the 85. Not sure it even matters, but I'd hate to find out this close to DGRR!

 

I thought about this more... no reason it should matter. I was worried about the vac ports not lining up, but that's silly.... they just have to line up with the carb throttle plate.

 

There are a number of different ones, but if you are emissions-deleted it may not matter all that much. Main difference is in the vacuum passages.

 

i think 81-85 are all the same, earlier DD is probably right

 

79-80 is different. There is a small channel in the spacer connecting both primary runners together. The channel moved from above to below the center for some reason. I think it's because the SA carbs had a fuel and air screw while the FB carbs have a single "mixture" screw.

 

so as long as i use the one that i've been using with this carb, the manifold swap wont matter? same carb, same spacer, earlier 79 manifold.

 

The manifold swap does matter because you have an open ACV port that is active on the 81-85 engines. You need to fill it in with quicksteel. The 79-80 manifold doesn't cover it.

Also look at the spacers. There will be a pattern or indentation that matches the manifold it came from so be sure it sits flat on whatever manifold you put it on to avoid vacuum leaks.

 

While we're on this carb spacer subject, (hopefully not hijacking) what's the general consensus on the paper gaskets from rebuild kits? The spacer on mazdatrix talks about how the gasket is permanently bonded to the spacer but I've never seen that. My spacer is actually open on one side, as in, I can see the channels in the spacer.

 

You've probably not seen many manifolds then because I've seen a lot and they are all like Mazdatrix said.

Hmm, I'd say go ahead and put a gasket on it from a rebuild kit and hope for the best.

 

Another thing to consider is the gasket paper in those aftermarket kits. It is a porous fiberous material that gas and oil soaks into easily. The OEM Mazda gasket is more of a solid somewhat thinner material. Not sure this means very much but just for your information.