Dedicated to the Promotion and Preservation of American Muscle Cars, Dealer built Supercars and COPO cars. |
|
|
|
#1
04-12-2022, 05:46 PM
|
||||
|
||||
x2 on the 50/50 mix with non ethanol.
As stated previously about the need to richen the jetting due to the LEAN ethanol blended Fuel. This is especially true on 1972 model GM's which leaned the jetting out in order to cut emissions, for example with the LT1 the primary jetting went from a 70 1971 to a 68 primary in 1972. With a leaner fuel PLUS leaner jets you really get lean on the mixture which also makes the engine run hotter.
__________________
~JAG~ NCRS#65120 68 GTO HO 4 spd Alpine Blue /Parchment 2 owner car #21783 71 Corvette LT1 45k miles Orig paint - Brandshatch Green - National Top Flight - last known 71 LT1 built. 71 Corvette LT1 42k miles Original paint - Black - black leather - only black LT1 known to exist. NUMEROUS Lemans blue Camaros, Monza Red and Daytona Yellow Corvettes & a Chevelle or two... Survivors, restored cars, & other photos https://picasaweb.google.com/lh/myphotos 
|
|
#2
04-12-2022, 07:32 PM
|
|||
|
|||
|
Yep, my 72 Z was jetted like that. The same as our 69 Z with a much smaller engine (68's in the primaries). Which just shows the direction they were going.
I currently run a stagger jet setup in our 69 Z with it's 302. 72 primary on the driver side and 70 primary on the passenger side. I generally stagger the rear the same but currently just have 76's in both rear. A track day I'll change it. Living at 5,000 feet elevation this actually returns very good drivability and respectable gas mileage (15 around town) and is slightly on the rich side. A good thing since we drive it down to sea level semi regularly and I know the engine is safe there, I don't have to fool with it. With the 5 speed it gets just over 21 mpg highway.
|
| The Following User Says Thank You to x33rs For This Useful Post: | ||
Xplantdad (04-12-2022) | ||
 |
|
|
Hybrid Mode
