How do I identify a 261 Chevy engine?
Casting numbers, not stamped numbers, on the 261 head are very visible beside the rocker arm cover. A different set of numbers relate to the 261 block. These seven digits are located on the right side between the fuel pump and starter except for 1954 where it is located forward of the fuel pump.
How much horsepower does a Chevy inline 6 have?
With a 230-cubic-inch inline six with a mild cam, headers, and the cylinder head work we’ve described, you could expect to make around 250 to perhaps 260 horsepower. Because the inline six crankshaft is so long, even with 7 main bearings it’s probably not a good idea to spin these engines much beyond 6,000 rpm.
How much horsepower does a 250 inline 6 have?
155 HP
Chevy 4.1L Specifications
| ENGINE | CHEVY 250 INLINE-SIX |
|---|---|
| FIRING ORDER | 1-5-3-6-2-4 |
| BORE | 3.875 INCHES (98.425 MM) |
| STROKE | 3.53 INCHES (89.662 MM) |
| HORSEPOWER (1970) | 155 HP (115.58 kW) |
What kind of engine does a Chevy 261 have?
The 235 and 261 was born. These engines stood up very nicely to all challenges and really helped boost Chevy’s reputation at the time. These days we see a lot of ’47-’53 Chevy trucks with the newer style 235 engine because most of them were replaced pretty early on in their lifetime.
What was the first feature of the GM 261?
After four years into production, a major quality feature was added to the 261 engine. For the first time a Chevrolet in-line six-cylinder came standard with a full flow oil filter system. This improvement, used only with the later 261, forced oil through a remote filter cartridge before it reached the engine.
What kind of oil filter does a GM 261 have?
For the first time a Chevrolet in-line six-cylinder came standard with a full flow oil filter system. This improvement, used only with the later 261, forced oil through a remote filter cartridge before it reached the engine. It was not like the optional by-pass oil filter system as found on 216 and 235 Chevrolet sixes.
How does the 261 GM 6-deves heater work?
In pure big truck form the 261 has a larger thermostat housing holding a double acting thermostat. This is designed to circulate water through the block and head before the thermostat opens to allow hot water into the radiator. Thus, no internal steam hot spots during warm ups, especially in winter.