I have a 55 Pontiac with the orginal 287 in it. I want to put an after market intake on it but cant find one will any other intake fit, like a intake for a 326 or 389 something like that any feedback would help. I do have a stock 4 barrel intake for it but would like to have an aluminum one for it if I can. Thanks for the help
The skinny on Pontiac intakes is this - 65-up are completely different, so forget that. 55-60 and 61-64 are similar, but there are various differences - running changes through '59 and a coolant passage change in '61. Some early aftermarket intakes compensate for this. Bottom line is you need to track down a 55-60 aftermarket intake to bolt on easily - they exist, but I'm not sure what kind of money to run one. I used to have a '56 4bbl intake around, if I could remember what I did with it, they take only a Rochester 4G carb though. Alternately, a 57-60 factory 4bbl intake should be able to be used and will take an AFB carb, or the Edelbrock clone thereof. Being a 287, you won't gain much going to more carburation, it may be just as well to run a stock 2GC or the Carter carb (I forget which they used) and live with it. You can also search for "pontiac engine tech" and find a long thread with more details in it.
To add to the excellent info from Rusty: Both the 1955 (287) and the 1956 (317) used both Carter WCFB and Rochester 4-GC carbs. The 1957 (347) manifold would accept the larger Carter AFB. 1955 through 1960 manifolds will bolt to the heads; HOWEVER, sometimes when the interchange books say something will interchange, not all of the misc. brackets do interchange. And while an A/M aluminum manifold is certainly lighter, none of them will perform as well as the original Pontiac cast iron manifolds. Jon.
carbking thanks for the input. I think Im going to run the original cast 4bbl manifold that I got and save myself some time and $ trying to track down an A/M one Thanks agian
You can swap to later heads and use a later intake manifold. Ive had good sucess with using a adapter to mount a afb carb to a rochester intake.
If you want to run a more modern AFB/Holley carb on your original intake, buy one of Speedway's carb adapters. Using your 55-57 intake means you will still be able to use the original generator mount bracket which bolts to the right-front of the intake manifold. The 57 intake is already made for a larger Holley/AFB/Edelbrock carb and has the generator mount. I have an extra '57 intake for sale if you want one.
------------- Also, performance-wise, there is nothing wrong with a 4GC Rochester. Over the years and on various sized GM engines, they came in at least two (and maybe three??) different sizes and airflow capacities. 'Back in the day' - early and-mid- '60's, - the hot set-up for bucks down racers and hot rodders running 283's and other small inch engines running 4GC Rochestors was to swap the small cfm stocker for one of the bigger, approximately 675-700 cfm 4GC's, as used on 371 and 394 inch Oldsmobiles and other similar, big-inch-V8=engine powered GM cars. Mart3406 ================
You do have to be careful of what high flow 4GC you try to use on your intake, as some of them had the larger, AFB sized bolt pattern.
Carbking is correct. The original cast iron 4 bbl. intake manifolds flow very well compared to aftermarket aluminum ones (if you can even find one). I took the old 4-jet Rochester off and installed an Edelbrock Performer on my stock 347 cast iron manifold and it runs absolutely beautiful. I don't think you will be disappointed. 55yak