1955-1960

[Greg Reimer 7376]

The heads on the 59 348 are the worst in the W motor family with tiny ports. That head is exclusive to the 348 block of that year due to water cooling passages-in other words, the 348 block in 58 can only be used with the 58 head. Later heads will result in a massive coolant leak by the spark plugs. A later 348 block topped with 58 heads would do the same thing. The World block is not only aluminum, but the bore size is way bigger than any maximum legal 348 overbore. The idea of the 61 Impala or Bel Air bubbletop with a 348/250 might work, and I think the hi-po 348 aluminum intake would be a legal replacement, since it was OEM. The '61 409/360 intake wouldn't be a bad choice, and some of the 4 jet carb guys are pretty good.Thirty years ago, a friend of mine in New Jersey had a 61 Impala 348/250 horse 4 speed combo that ran O/stock, went 13.00 at 103 back then. Broke a lot of rear ends.

[Alan Nyhus]

From a motor/transmission aspect, the '61 348-250 with an automatic would be a good setup. These came with both PG's and TurboGlide transmissions...so running a TH350 would be the way to go. The high perf 348-305/340 h.p. alum intake probably wouldn't fly, as they used a Carter AFB (much bigger area under the carb) versus the 4GC on the 348-250. The 305's were hydraulic cams and the 340's were solid lifter cams.

A Biscayne or Bel Air sedan, a one piece driveshaft, and a 12 bolt in place of the original housing assy. would make for a pretty slick stocker. These motors are still available and pretty inexspensive.

[Geerhead55]

With all due respect fellas,,,the thread is about 1955-1960 automobiles,,the '61 combos you're discussing could've been built anytime in the last 49 years, as I'm sure they have been.
Also all '61 Chevy 2-dr. hardtops,,Bel-Air, Impala and Super Sport are "bubbletops" so no need to be redundant. The term was properly used to differentiate between the '62 models when the new roofline came out for the Impalas and Super Sports, whereas the Bel-Airs retained the previous roofline,,but then you guys knew that didn't you?
Danny Durham

[Alan Nyhus]

Originally Posted by Geerhead55

With all due respect fellas,,,the thread is about 1955-1960 automobiles,,the '61 combos you're discussing could've been built anytime in the last 49 years, as I'm sure they have been.
Also all '61 Chevy 2-dr. hardtops,,Bel-Air, Impala and Super Sport are "bubbletops" so no need to be redundant. The term was properly used to differentiate between the '62 models when the new roofline came out for the Impalas and Super Sports, whereas the Bel-Airs retained the previous roofline,,but then you guys knew that didn't you?
Danny Durham

It's worth noting that not all '61 Impala 2 drs. were hardtops. They were also available with the 'flat top' roofline..like the Biscayne and Bel Aire sedans...complete with post. I owned a '61 Impala 2 dr. sedan (not hardtop) in the early '90's.

But you knew that, right?

But since were not supposed to talk about '61's......

[Geerhead55]

Absolutely Alan,,I knew that. I got into a discussion with a gentleman at a swap meet one time on a '61 2dr. sedan. He preferred to call it a coupe, whereas I tried to explain that I called it a sedan because of that post and frame around the window,,but he wasn't having any of it,,called me a young whippersnapper and threw his hands up in the air. I was 55 at the time,,,don't know how old he was. It was kind of funny,,,take care.
Danny Durham

[Alan Nyhus]

Laffin', here...... -Al