300-4

[kevin h]

I have a 67 skylark w/ a 300-2bbl. if i get a 300-4bbl intake from an earlier buick, would it be worth it in terms of performance, and would it just be a quick replacement or would things have to be rerouted or modified to the new intake??

 

[gungeey]

As far as increased speed, I know of no published test to compare between a 2 and a 4bbl in your 300. You would have a performance "look", but a big ingredient in the original 300-4 barrels is the 11:1 compression ratio. Your 2 barrel engine is factory 9:1, by now probably a tad higher due to prior milling, and built up carbon. That's why you can put regular gas in your present configuration (which you wouldn't be doing with the HI-PO version). If you wanted, you could put a performance cam in with new lifters to take advantage of the bigger carb. Keep it mild, though, or those cast aluminum rockers will start crying!! If I were going your route, I'd add to the intake the smallest 4 barrel Carter AFB I could get my hands on. To me the best part of the changeover is hearing the 4 barrel open up! Steve

 

[gmranch]

If you have the switch pitch trans, try to get the idle switch bracket with the 4 bbl set up. If not, the 2bbl bracket can be modified to work. A mild cam and a dual exhaust system, with a balance tube, are all you need for significant increase in performance.