Ok I have a slant that needs new goodies on it. What am I going to need to slap on a 4 barrel? I have a holley 750, and am getting the manifold. What else will I need guys? I really need help. Thanks

For the 4bbl to be worth it you better have done some head work, cam, exhaust, etc.

I ran a 1050 Dominator on a 170 slant six in my Imperial. It ran low 12s in the quarter........

the 4bbl Holley you want is a 390 CFM one & iirc there's 2 versions or a throttle adapter that you need to pick from but these guys will guide you. www.slantsix.org

My brother ran a 66 dart, w/ a 225 back in the day with a stone stock engine and we put on an offy and 340 carter avs....made a HUGE difference in performance!!! sounded mean with that throaty carter sound too

Ok so 750, too big. But let's say between 600 and 500 good? Engine is stock. No work done to it other than after market exhaust. I'm planning to bolt on a 4bbl with the offen manifold from summit. I've seen this done with no head work and got good results. Sound better guys?

As was previously mentioned, a 390 Holley will be plenty of carb. We fabbed a header system (I think the tubes are 1 1/2") that goes into a 3" exhaust, used a Clifford intake and all is good. Stock slant with an od 4spd. Gawd, I love that car. Don't over carb. You will be disappointed.

Ok so 390 sounds good. But are there any major parts I need to convert to a 4bbl. The throttle but other than that? To be specific its a 72 duster, and want some more power. Thanks guys

Clifford has a website as I remember. They have performance cams-head-headers etc. If you really want to go fast, talk to the guys in the induction section here.

Actually unless you are set on a holley prob one of the small '60's AFB's would be fine and for sure be cheaper and tuned right a carter/brock would be better for mileage/driveability at part throttle than a holley but the 390 may be an exception but I do know that it is the std holley used by the /6 boys for 4bbl swaps. I really would checkout the other site

I have seen and used 600 holley's on slant 6 engines run a heavy spring on sec and it will work just fine same goes with 750 way too much carb and pig rich but you can use it with a heavy spring brown or black. Just I don't want to bhe behind you in traffic unless your real good at idle circuit mod's

You need to learn some basic engine hotrodding principles.

You could actually get a cheap Carter like another poster was saying. Have it rebuilt.

The Offy is a decent intake. I am curious about the Aussiespeed Hurricane. It looks like a better design.

Clifford is really bad about customer service.

Come on over to the slant site!

We'll be there!

IF the rest of the motor is going to stay unmolested, save yourself a headache and watch for a used Offy intake and get a decent 390 vacuum secondary Holley. IIRC the list number you want is 8007.

An Offy will give better low end performance on the street than a Clifford.

Is the car stick or auto? For a stick you can just get a universal bracket for the throttle cable, for an auto you'll have to fab up kick-down linkage too.

You will also want to do some exhaust work, either split manifolds or a pair of headers. You'll be glad you did.

When I first started with my stock 225 I bought a 2bbl Cast Iron intake and mounted a 2bbl 500 Holley to it...Too much

I then mounted a modified 4bbl 390 Holley with a 4bbl Aluminum Offy Manifold, placed a secondary metering block on the rear. Ran okay...not great...but she had some extra power.

I then added the Direct Connection Slant 6 into 1 header...Heavy denting on the #4 or #5 tube to clear the power steering unit....Ran like that for 2 yrs...

I went to the boneyard and found another head in decent condition, sent it out, had a mild cleanup in the bowls performed, 5 angle valve job, replaced all the seals and the valves, opened up the intake and exhaust ports. Milled it .100 to bump my compression up. My main purpose was to remove the 3/8" stems and replace them with 5/16" Fords but the guy at the shop said its a waste of money and leaned me towards the 5 angle job. I put $1500 into that head

Rebuilt the entire motor, replaced the pistons, matched a working set of rockers (they tend to crack on the surface). Got a .436 lift Isky cam. Swapped over to MSD at this time because the Orange ECU was being replaced every 6 months for some reason. I bought a set of Tri-Y headers from Clifford. I heard about the bad customer service so I ordered the plain coated ones, drove to pick them up (3 hours road trip) I sent them in to another place and had them coated for 100 bucks.

Slipped that head on to the new motor, bolted on a rebuilt 904 w/ shift kit. Installed the Clifford Tri-Y headers, the aluminum 4bbl Offy with a 500cfm Edelbrock....That setup was immaculate...I drove it everywhere...I think there was a time span of about 7 months that I didn't even lift the hood once.

Check out the link in my signature and you can read all about the mighty slant, where she came from and where she went...Pics are there too