is it possible to install a holley four barrel on top of the stock factory manifold??

 

No. need an adaptor or racingbeat intake

 

Actually a few have done it using a modified spacer w/ mixed results. I personally saw one used on a 1/2 bridged 12a w/ a holley 600, and that thing was a beast. I still would go the RB intake route.

 

I have an aluminum adaptor to mate a Holley/Edelberock to a stock manifold. Either 12A or 13B - it has both stud patterns.

Now I just need a final answer on the need for channels. I think I'll start without channels and then do like peejay says and cut one in the secondary runners. If that solves things I'll leave the primaries seperate as they are.

 

From most people's experiance with doing that, leave the intake alone. Run an open style spacer to give fuel to all four runners at once. Makes tunability a little easier. I have seen this work well with the Racing Beat intake for a stockport.

 

Heres one on ebay! http://cgi.ebay.com/ebaymotors/mazda...QQcmdZViewItem

 

Anyone else notice how interesting that manifold looks? I've never seen one like that before. There's no ACV. I do have one of those nipple valve things in the picture. It has the same thread pitch as the old style brake booster banjo bolt, and a one-way valve like a PCV valve. They don't seem to work that well for brake boosters due to the one-way valve operation. At least that's been my experience.

 

Been there done that. Haven't had a suitable test engine to try it out on yet. Just had the parts kicking around and a bunch of time to play.

 

Ohhh, and a tube of jbweld to spare too, lol.

 

Considering the difference in performance I noticed just by replacing the stock manifold with a ported one, I wouldn't dare put an aftermarket carb on a stock intake anymore. The stock mani doesn't flow the best, and if you're going to spend the money on a Holley, might as well get a Holley manifold.

RB makes 'em, and that would be much better than rigging up the stock manifold to work.

As for the "open style spacer" bad83 mentioned, I seem to remember Carl talking about why you wouldn't want to run with all four open like that. I can't remember the details, but Jeff if you're thinking of running an open spacer, chat with Carl and get some feedback from him about it.

Jon

 

I was going to cut a channel in the secondaries, but leave the primaries seperate. I believe that's what peejay and Carl recommend.

 

Correct! My project was with junk i had kicking around. I even have an old holley to play with as well. For anyone else, i say pay the piper and buy the package to begin with.