intake 225..231 of to ef

:? OK... from what i have found out so far is nothing??? well not nothing but, lets start from the start.. i have a 1977 231 EF i'm looking for a 4 BRL intake for it. i was told the 231 EF intake will interchange on a 225 OF from 1978 and before supported by other threads on this site. then i also, found information that OF and EF (pre 1978 ) won't interchange also, supported by theads on this site. i also found information that stated only 1976 to 1978 231 EF will interchange with eachother and the 225 OF and 231 EF pre 1978 wont line up right. then on this site i found it said that all pre 1978 intakes will interchange. ..SO. i really dont understand what will fit. i found a 1971 225 OF 4BRL intake but i dont have any idea if it will work for a 1977 231 EF. i know this type of question has been asked before but i cant find the whole story...all i really want to do is run a 4BRL carb on my 1977 231 EF without having to pay loads of $$$ to do so (thats way i'm looking for a used intake with iterchangability [i think thats a word])!! any help would be great THK.. :?

 

Before you think 4bbl, invest in your heads first.

1977-78 had marginal heads and, unfortunately, a 4bbl will likey struggle to operate to its potential. A way to solve most of your problems is to go junkyarding. Look for early 80's GM fullsize "tanks", especially Buicks. Many base models had V6's in them for fuel economy. The only V6 offered is the "tanks" was a 4.1 which was a special casting of the 3.8. This V6 is easy to identify by looking for a 4bbl Rochester under the aircleaner! This intake will fit on the 3.8's! 8) Take the whole engine if you find it and sell what you don't need.

The problem is that the 4.1's are highly desireable due to the turbo crank inside and the turbo guys like the bigger block. You may have to check out-of-the way junkyards.

Bottom line, find 1979 or newer "high port" heads. Minor porting "bowl hog" under the valve opening is a cheap 20+ HP. (Buick guru's claim 28HP or so --Mine are being done for $50 right now). I'm changing to Manley "severe duty" stainless valves in the stock spec for durability and flow. ($17 each -- $200/set ). The back sides of these valves are shaped for optimum flow (stock isn't). A Dauntless is fine without stainless valves but aftermarket probably isn't a bad idea for unleaded.

 

thanks for the info. when i redo or build another 231 i will use that information. also, i think the coolant passages are part of the prob. matching intake to head. but the fact remains i still dont know what intake will fit right?? does anyone know what will interchange (pre 1978 EF/OF 225/231) :?