I have a 1957 Chrysler 354 Spitfire (Poly) engine. It comes with the stock 2bbl intake. I want to convert it to a 4bbl. First, is it correct that an intake from a 331-354-392 Hemi will work? Second, I understand there is no low profile single 4bbl aftermarket intake for this application. Is this correct? Finally, does anyone have a 4bbl intake for my engine? Thanks for any help. James
The 354/392 intake (and exhaust) manifold will fit, not sure about the 331, I think the water routing was different on them. The 354 hemi heads are a bolt-on, too, if you can find them. 392's won't work, though.
'55 331 & up intakes are supposed to fit. To change to Hemi you would have to replace the pistons also. Those Poly valve covers look cool chromed! Check the classified here, & @ www.hothemiheads.com also.
First of all, any 331/354/392 intake will all fit. 1951-54 intakes had the thermostat in the manifold, and that would duplicate the one on your water crossover. 1954 was the first year Chrysler used the four barrel WCFB carb, but only some of the 331 engines got the four barrel carb (I think the early ones were two barrel), making it unique and rare (read: expensive). The 1955 and 1956 four barrel intake manifolds have the smaller carb bolt pattern, requiring the use of a WCFB carb or a spacer/adapter to use something bigger/newer. I would recommend you use the casting number 1731703. This manifold was used on the 1957 and 1958 engines with a four barrel carb - 392 hemis as well as the four barrel equipped 354 poly engines. I recommend it because the bolt pattern will allow the direct use of a small-pattern AFB carb. You stated you wanted low profile - this manifold is about the same height as your two barrel intake, and not needing a spacer/adapter helps keep the carb down low. These intakes come up on ebay often, and typically sell for only ~$25.00
Thanks all for your input! I found an intake as per the recommendation on this list, the 1731703. I will post some pictures when it is set up.
the Edelbrock carbs are drilled for the small bolt pattern. You can open up the bore holes, or install longer carb mount bolts & use a spacer
The 354 intake will be a better fit due only to the size of the exhaust crossover. If you use a 392 intake you must use the 392 intake gasket. The best way to 'improve' the intake is to inlarge the throttle bores. Just match the Holley bore pattern, lots of meat-no worries, and then you have your choice of carbs. You will only need a thin bolt pattern adapter for a Holley carb. Major flow improvement on a serious street engine! Happy Motoring.