Gas Mileage Differences between 305 and 350
01-20-2002, 02:06 AM
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Gas Mileage Differences between 305 and 350
I was thinking since I need to rebuild my engine...again 
Should I rebuild my LG4 or go with a 350???? Between a stock 305 and a stock 350....is there major gas milage differences??? I dont really wanta put in a 350 if its gonna give around 10 Mile to a gallon. I want some power and some good gas mileage too. My LG4 gets me only about 160HP and 13 miles to a gallon with a TH350 transmission. Probibly puting in a T-5 would help with the milage too. Thanks guys.
Should I rebuild my LG4 or go with a 350???? Between a stock 305 and a stock 350....is there major gas milage differences??? I dont really wanta put in a 350 if its gonna give around 10 Mile to a gallon. I want some power and some good gas mileage too. My LG4 gets me only about 160HP and 13 miles to a gallon with a TH350 transmission. Probibly puting in a T-5 would help with the milage too. Thanks guys. 
01-20-2002, 03:54 AM
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mileage
OMG 13 mpg, even my l98 gets better mileage then that. i mean i think the mileage is a bit low even for a 350 at 18mpg average half city half freeway driving, but i have some suspisions where the mileage is going.
a decent 350 can still turn in over 20 mpg if it is tuned and running right. i keep poping a lean at cruise code so i know the motor is going over rich to compensate.
a decent 350 can still turn in over 20 mpg if it is tuned and running right. i keep poping a lean at cruise code so i know the motor is going over rich to compensate.
01-20-2002, 07:52 AM
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Car: 99 Formula
Engine: LS1
Transmission: T56
Axle/Gears: 342
It's all in how the motor is built and driven. One guy get 30mpg with his 350. TPI will best for gas.
I get 17-18 and that's with a Non-lockup converter.
I get 17-18 and that's with a Non-lockup converter.
01-20-2002, 07:58 AM
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Car: Death Mobile
Engine: 666 c.i.
Since your Canadian, you will understand my metric numbers. Last summer I took a trip from Kamloops to Calgary (610 Kms) and I only used 49.5 Litres of gas. This is driving through the Rocky Mountains and passing lots of slow moving RVs.
I have invoked Highway Mode in my eprom though.
I have invoked Highway Mode in my eprom though.
01-20-2002, 02:47 PM
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Car: 1989 C4
Engine: L98
Transmission: 700r4
Axle/Gears: 307
A 350 will get comparible fuel economy to a 305 under normal conditions. If you want good economy with a 350 use a replacement truck cam like the melling MTC-1. Torque cams provide great fuel econmomy, especially in cars. My firebird in my sig gets 18mpg city without driving like a granny.
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01-20-2002, 04:29 PM
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Originally posted by Mark A Shields
with a Non-lockup converter.
with a Non-lockup converter.
Whats that?
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