Older Holley projection 2bbl

Im going to pick up an older 670cfm 2bbl Holley projection system. Its used but is supposed to be complete including manual and was working fine when it was removed recently. Im getting it cheap... to cheap to pass up even if Im not sure what to put it on yet. I was thinking of putting it on my stock 200. I have been told that they are easy to scale back and tune compared to carbs so size shouldnt be a problem. From what I have heard the performance improvement is worth the trouble going to a 2bbl carb but the tuning can be a bit tricky so this is why Im thinking of this system. Ultimately I want to go with something better with o2 and other sensors to make it run even better but for now Im hoping this will be a cheap toy that will be fairly easy to make work

Anyone tried it? All I could find in a search was talk about the 1bbl version they no longer offer.

Thoughts? Ideas?

analog or digital?

Its the analog one. I just got it home. It seems to be complete and it has the instructions. Its got a really wide bore, it looks like it was on a spread bore manifold on the back bores. I cant quite figure out what the guy was doing with the stack of adaptors that was in the box. The mount plate seems to be for a Qjet type of spread bore but he had a Square-Spread adaptor on upside down so the square side was against the q side of the TB and from the looks of the gasket it was on a square manifold with the q side of the adaptor down... Not a very smooth flow to say the least..... I guess it was in an RV that wouldnt pass emissions somewhere..... oh well his loss (I hope)

It does not seem to have the o2 sensor option

If I try to make this thing work on the old log 200 I assume I will have to make my own adaptor and air cleaner to clear the hood? By the looks of things I could make an adaptor that would just line up with one of the bores in this thing and only hook up 1 injector? Is it really that easy? It would look funny but it may work. It was cheap enough I mostly got it to play with, maybe I should just put it on my little cadillac 425/7.0?

Some specs...
11-18 Psi regulator
80lb/hr injectors
670 cfm @ 1.5"

It would be PERFECT for the caddy.

A bit much to get mounted on a log, though.

I installed a pro-jection system on my '73 ford fe motor. It is designed to work with a 4bbl manifold so adapting it to the log would put your height through thr roof, literally. Also as linc said it is wayyyy overkill for the 200. That doesn't mean it cant be made to work and if you do I'd be interested to see how it turns out. Good luck. -David

I decided to go the tempo CFI route for the stang. My thoughts is as long as Im stayin with the stock log there is not going to be much benifit trying to squish a lot more into that one hole, like you said to make that a smooth transition it would be sticking out the hood like a blower. I have messed with square bore 4bbls on spread bore manifolds and there always seems to be issues making the transition unless you mill out the manifold or use a taller adaptor but there are down sides to both those options too. Flow inside the log is interesting enough without adding a few more sharp turns and places to loose the fuel suspension. Now going multiport with some sort of forced induction? Solves lots of flow problems but not the route I want to go.

could you post some pics of the carb i am very interested in seeing what it looks like

Justin, What do you want to see pictures of?

the holley carb(or what ever it is)

Got it..... I have to go fight with some stuff in the driveway today since its about 30* for the first time in a long time but if that dont take all day I will get my self setup at one of the photo sites and try and snap some pics. Its a pretty dang simple set up.... makes an 1100 look complicated.

thanks man ive never seen one or even heard of one before and it sounds interesting and by all means dont rush through your other things your doing to get the pics cause i can wait

Front view



Rear view




Bottom view (with standard 4bbl mount)



Control box. Its hard to see in the pictures but there is a knob for Choke, Accel Pump, Idle, Mid, & Power.

I think when this one came out it was the only model but later they came out with more versions including a 1 & 4bbl one. This one was rated at 670 cfm and good for around 300 HP. I have seen them on ebay for $250-400. There are also newer versions that have a digital control box that you tune with a computer. The TB's look the same except they now have a Idle Air Control motor instead of the solinoid that the early ones have.

IIRC,that unit(HolleyPro-Jection)came out in the mid 1980`s.
Leo

Holleys website list this for V8 ONLY, NO 4 or 6 cyl.
Might want to talk with their tech folks.