This might be a sin, but

[ahpook]

I'm really, really sick of the ZS carb on my '79 1500. I've rebuilt it over and over, and it just is a nightmare. I've seen a few sites where people mount either a single motorcycle carb (Mikuni, Keihin) on the intake, or to be showy mount four carbs, one for each cylinder. My experience as an old bike rider says these carbs are "set and forget". Has anyone here done this, and where would I go to get a custom intake made up? I'll admit I do like the look of four nice new carbs in a row....
Thx, George

 

[Trevor Jessie]

I can't help with the question, but why not just use a Weber?

I hear they work well on the 1500's.

 

[drooartz]

I've seen a few of these, but can't remeber the specifics. I know some have been used with engine swaps, and I think I've seen some on the 1500s. You might also look at a single SU setup.

A 4-carb setup would be pretty neat, but I can't imagine it would be all that much easier than a single SU.

 

[bugimike]

I would think synchronizing four carbs would complicate things!! 1 Weber carb would do the job so much more efficiantly and looks good too!! (especially the side-draft set-up with velocity stacks - looks very racy!!)

 

[michalotti_tr]

You want to go look at Performance Research Industries website (www.prirace.com) They specialize in that type of setup and have manifolds and everything for the 1500 engine

NFI, just really like the looks of what they have

 

[ahpook]

yeah, that's one of the places I've seen it. Their website is down, but I got a price from them of around $1350 for the whole setup, and they won't sell me one without the carbs. Which is a shame, because I have a set each of Mikunis and Keheins sitting around.
And no, tuning them is sooooo simple: four vacuum guages on the intake side. Dial 'em right in...

 

[aeronca65t]

My 1500 racer has a single bike carb.
Our EMRA race regs allow any carb but require standard manifold configuration.
I'm running an S&S 2-1/8 "pumper" carb. These are normally fitted to big-bore Harleys. It's great at speeds above about 4000, and has a decent idle circuit, but it'd poor at midrange (where street engines run). I get about 12 mpg at race speeds.

I will likely re-fit this engine into a street Spridget in '07.
When I do that, I'll fit it with a single HS4. I had the HS4 on this engine before when it was a street engine and it was pretty nice.

The other 1275 race car I occassionally co-drive has a single HS4 and it will pull over 110 MPH with a windshield.

The idea of 4 carbs on a 1500 is unusual. The 1500 is basically a long-stroke, low RPM engine. I limit my 1500 to 5800 RPM max and I replace rod bearings every 25 hours or so.
With 4 carbs, you'd need a wild cam and high RPMs to really take advantage of anything. This would not play to the 1500's torquey nature. You'd need to replace bottom end bearings quite often.

 

[Bugeye58]

You'd need to replace bottom end bearings quite often.

And cranks, and oil pans, and blocks, and............... /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff
Former 1500 racer.