Can someone tell me if either of the following old hi-rise intakes are desirable to use on a mild built 318? Or any other info. about them.
1) cast iron hi-rise with casting # 3462848 1
2) aluminum Offenhauser dual-port with casting #6006

Always appreciate the help.

I can`t help with those intakes but the best 273/318 intake I had used was the Edelbrock LD4B. Kinda hard to find at a fair price anymore.

That cast iron intake is a very good intake, came on a '70 340. Don't waste your time with the offy dual-port. An Edelbrock LD4B is the 318 version of an LD340 intake, try to find one of those. Also good small block intakes are the Performer RPM, Torker II and the Holley Strip Dominator. DO NOT use a Torker 340, it will kill your power.

8The LD4B and LD340 are very different intakes. If you want an LD4B for your 318 project look no further than the Weiand Stealth, its pretty much an exact copy of the 4B.

The iron manifold is most likely valuable only to a restorer or a racer needing a factory iron manifold for a specific class. If you are want to put it on a 318 you should gasket match the heads or run 340/360 heads or else you'll have port mismatch in a direction that will affect performance.

Not on a mild 318 it won't.

This old chestnut gets pulled out whenever anyone want to put a 4bbl intake on a 318. If you are actually building the 318 to the point that this issue rears it's head you are building the WRONG [censored] engine. You should be building a 408 not a 318.

You're right Supercuda, putting 340/360 heads on a 318 will drop the compression and make it a dog. The op will be far better off using a 318 small port intake (like the LD4B) that is designed for that engine and heads.

Honestly, I put 340 heads on my 72 Charger 318 and it ran pretty good for a big car. It ran a best of 15.1 at the track back in the late 70`s.

i had a 69 coronet 318 that went 12.96 @ 104 with a big tq on a eddy performer

I didn't say a thing about putting 340/360 heads on anything. I said running a 4bbl carb on a mild 318 will not a problem. The slight mismatch between the 4bbl intake and the 318 heads won't be noticeable till you are so far into a 318 that you are foolish for not just building a 408 instead. A mild 318 will never notice it.

The cast iron intake will work just fine for a 318. Port match if you wish. I like the slightly later factory spreadbore intake, IMHO it's a real high rise intake. I matched the intake port on three sides because I had the time but it's not necessary

The Offy Dual-Port was a novelty when it was built It sounds better than how it works. It was supposed to aid fuel economy. Put it on ebay and someone will bid on it for sure.

Steve Dulcich tested one in his 383 intake shootout and it was a dog.

R.

You could bolt on the cast 340 intake and not worry about the port mismatch, the factory essentially did the same thing with the 80s 4bbl cop motors. A better choice would be the non-air gap performer, which will also let you run factory AC.

80s cop motors got 360 heads stock

I have a LD4B and can say on a bone stock 2v 318 it is hands down night and day difference from a stock intake/performer intake.

add mild cam/headers it is even better.

I ran it on many 360 headed 318s and performance was great for a 318

I also have a holley street dominator that is another good intake for a bone stock 2v 318

even though it is open plenum/low rise it is a little screamer of an intake for the street on a mild 318

as far as 360 heads on a 318..yes it does low comp yes it does make a dog on the street with a stockish cam...but use a hughes whiplash or the right cam/TC/gearing in a light car they cam be a little surpising on the street.

I had a few lopo JY 360 head 318s add the TC/gears and wind up rpms like a 340.

ask member CLASS OF 65 about the record holding 273 engine he has in an a-body talk about rpms..


if a hipo 273 can do it a 318 can do it IMHO.

myself.. the rpm airgap I have is a little much for a mild teen with out uping the comp ratio/TC/gears

my 318 with a 273 hipo solid lifter cam was pretty hot shifting it at 6500 rpm 4 speed and 3.91sg and had the holley street dominator and a 600 cfm

some of the old stuff still works right on par with the newer stuff now days till you go apples vs oranges with them.