Senior Tech Team
Join Date: Sep 1998
Location: Mustang, OK USA
Re: What is a RAT motor?
A lot of the terminology for Chevy engines seems to be dependant on what part of the country you lived in, what racer organizations you were affiliated with and what car brand you associated yourself with.
The "W" moter term really never was very common until well after the introduction of the MarkIV big blocks (introduced by the 396 in mid-65). The term Rat motor WAS used for the 348-409 family BEFORE the MKIV was introduced in 65, but depending on where you were located, more so at some places than other places. BEFORE 1965, I clearly remember people refering to 348-409 engines as rat motors. Back in the 50s and early 60s, the engines at the dragstrips were not quite as defined as they are today. For the most part, today, Its SBs, BBs and then the HEMIs. Back then, it was SBs (or mouse motors), Rat motors (which were the 348s-409s), Pontiacs, Olds, Hemis, Fords, some Cad motors (for you that are not knowledgeable, there were some 2x4 Cadillac engines in 55-57, replaced with 3x2 in 58 and the Cad went to a 390 in 59), AND, the flathead Ford was still kicking quite well. The biggest early Hemi (it wasn't HEMI back then) was 392, the biggest Olds was 394 (oh ya, in 57-58 Olds had a 3x2 setup, called the J2 engine), there was a 430 Lincoln by 58 and Ford had a 390 by 61, eventually becoming a 2x4 406 then a 2x4 427. When the 58 392 Hemi went away, Chrysler Corp didn't really start coming on strong until the 2x4 413 followed by the Max Wedge 426, and then the NEW HEMI in mid 64. Last of all, Buick stepped in there with the 2x4 425 "Nailhead" motor (which only lasted until 65, when was the last time you saw a streetrod with a 2x4 Nailhead?). ALLLLLLLLLLLLLLLLLLLLLLLLL of the above was BEFORE the MarkIV Chev BB of mid-65.
So, back then, you saw EVERYTHING at the dragstrip, not so much today.
Anyway, the 348-409 family BACK THEN was commonly called Rat motors and the 283-327s were commonly called mouse motors. In the VERY EARLY days of the MKIV BB, it was common to hear the term Porcupine motor (this was derived from all the various angles of the valves sticking up from the head). In time, the terms pretty much have evolved down into SB and BB. Yes, you still here the term Rat motor, but it is NOT as common as it used to be. So, the term Rat motor was used for BOTH the 348-409 and 396-454 families, and then has pretty much given way to the term BB, and now "W" motor for the 348-409s. But back when the 348-409 were common, the term W motor was virtually non-existant.
Light travels faster than sound. That is why some people appear to be bright until you hear them speak. (unknown)