05-13-2010, 08:01 AM | #1 |
dang its hot
Join Date: Nov 2006
Location: frankfort kentucky
Posts: 1,349
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engines and mileage
gas is killing me! This big block is fantastic but gas....13 MPG ish...what are your experiences with 350's? my 305 in this same truck got 13-14 and wouldn't pull your hat off your head. Now I slap curbs but what about an in between engine? comments please....
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05-13-2010, 08:55 AM | #2 |
Never Satisfied
Join Date: Sep 2009
Location: Sherman, Texas
Posts: 360
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Re: engines and mileage
go gen III. either the 5.3 or the 6.0.
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1973 4x4 Blazer- Parting Out 1986 LWB Silverado Undergoing LQ4/4L80E Swap '86 Build Thread:http://67-72chevytrucks.com/vboard/showthread.php?t=390566 |
05-13-2010, 09:22 AM | #3 |
Slots go on anything!
Join Date: May 2003
Location: Richardson, TX
Posts: 5,957
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Re: engines and mileage
If you are getting that kind of mileage out of a 454, you should be thrilled. The one in my '73 averaged somewhere around 6 MPG, and the one in my '75 Blazer was probably closer to 4. Of course, neither was built to be a daily driver, either.
My '87 SWB with a stock TBI 350 averaged around 17 with a 700R4 and 3.42 gears, as a comparison.
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1974 Jimmy- 5.3/4L80e/NP241 |
05-13-2010, 09:30 AM | #4 |
Senior Member
Join Date: Jul 2009
Location: Hayden, Al.
Posts: 4,148
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Re: engines and mileage
Go this route and you will not be disappointed! Good power, good mileage, and the always important Coolness Factor.
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05-13-2010, 09:43 AM | #5 |
Registered User
Join Date: Mar 2010
Location: Kentucky
Posts: 32
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Re: engines and mileage
13 mpg out of a big block, I would be doing backflips.
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05-13-2010, 09:49 AM | #6 |
On a budget like Fred Sanford
Join Date: Oct 2005
Location: Topeka, KS
Posts: 2,031
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Re: engines and mileage
+1!!!!
The 5.3 in my 2001 tahoe has only pulled better than 14mpg once, and that was going down hill with a tailwind.
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'85 Silverado swb: 383 stroker, 10.5:1, vortec heads, 232/238 roller cam, RPM air gap, performer 750 carb, stainless longtubes, 3" duals/super 44's, T56/4.11 383ci build / exterior refresh thread '98 Camaro z28: 370ci twin turbo 370ci build '01 Tahoe LT 4x4: 5.3, longtubes/ory, magnaflow duals, custom tune....wife's DD |
05-13-2010, 09:57 AM | #7 |
Registered User
Join Date: Jul 2007
Location: Tucson, AZ
Posts: 3,189
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Re: engines and mileage
My partial gas mileage history:
73 C20 454, TH400, No A/C - 10-11 mpg city - 13 hwy 76 C20 350, TH350, A/C - 9-10 mpg city - 13 hwy 83 C20 454, 4 Spd granny, gear vendor, A/C - 11 mpg city, 13-15 mpg hwy Big old pickups, especially 3/4 ton, don't get good gas mileage, unless you go to 1/2 ton V6 stick, then I have seen/heard of 18/22 mpg. Newer pickup gas mileage history: 2000 Silverado V6 auto - 18-19 mpg. city, 22-23 mpg hwy 2003 Sierra ext. cab, 5.3 auto - 17-18 mpg city, 22 mpg hwy. All above vehicles were driven like grandma on her way to church, not like a teenager. Modern pickups can routinely get 17 mpg. city when driven carefully, whether diesel or gas. That's about it. While this is not popular on this forum, if you don't need to drive a truck on a daily basis, a truck is a bad daily driver (based on fuel economy only, which is the basis of your post.) Having said that, I won't get rid of my old 83 beater pickup (second vehicle) any time soon, especially since it has a handy stealth dump bed. |
05-13-2010, 12:25 PM | #8 |
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Join Date: Jun 2007
Location: Cape Coral, Florida
Posts: 1,123
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Re: engines and mileage
My 86 swb with a 305 and 700r4 with a 2.73 rear gets 17-18 mix of city highway but has no balls, I wish I had a BBC knockin back 13!
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05-13-2010, 02:58 PM | #9 |
Registered User
Join Date: Oct 2009
Location: Buhl, Idaho
Posts: 1,438
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Re: engines and mileage
i get about 10 in my 1 ton. with a carb that's tired. what kills me is the turbo 400 on the highway engine screams! If you do a 5.3 or 6.0 swap even though you can have 300hp easily by the time you make up the difference in cost it will take you forever. But it would be way cool to have a 5.3 or 6.0! not dissing people that have them. I would like to do a cummins conversion to mine or 6.0. with a nv4500.
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86 c30 crew cab dually 454/400 4/6 drop SOLD 1-8-11 1981 chevy K10 short Bed Scottsdale SOLD 10-26-2020 67 GMC Stepside Straight six/3 on the tree "The Peach" 2020 Silverado Double Cab LT Z71 5.3 8 speed Daily Driver K10 build http://67-72chevytrucks.com/vboard/s...d.php?t=671934 The Peach build http://67-72chevytrucks.com/vboard/s...d.php?t=733903 |
05-13-2010, 04:39 PM | #11 |
Registered User
Join Date: Nov 2006
Location: Amador County, Ca.
Posts: 229
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Re: engines and mileage
My 454 TBI with th400 in a 4x4 crew cab one ton is about 8 mpg
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1995 GMC 4x4 1/2 ton 1999 Jeep Wrangler w/ 33's 68 camaro 350/350 1987 Chevy 3/4 ton 4x4 Suzuki DRZ 400s Dual Sport 1971 chevy long bed 2x4 194? Dodge 2.5 ton 1980 Chevy Cheyenne 4x4 1/2 ton I6/sm455 1989 Chevy V30 crewcab dually 454/TH400 |
05-13-2010, 04:43 PM | #12 |
Resident of Here
Join Date: May 2008
Location: Wesley Chapel, FL, USA
Posts: 7,716
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Re: engines and mileage
Get a 6.2 diesel. My K10 got 24mpg hwy and would jerk your hat off your head and beat new tundras. Add a turbo and you win even more!
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~Bradley~ 2004 Black GTO LS2/T56 too much to list Miss having a truck |
05-13-2010, 05:00 PM | #13 |
dang its hot
Join Date: Nov 2006
Location: frankfort kentucky
Posts: 1,349
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Re: engines and mileage
wow...maybe I should just trade or sell this and get a late model or a diesel burban...or maybe not...I dunno...get the bike going again, then theres that scary road rash thing...
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05-13-2010, 05:35 PM | #14 |
Registered User
Join Date: Sep 2009
Location: Monroe,Iowa
Posts: 4,370
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Re: engines and mileage
I quit carring about MPG,now it's SMILES per mile!!
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05-13-2010, 06:00 PM | #15 |
Registered User
Join Date: Oct 2009
Location: Buhl, Idaho
Posts: 1,438
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Re: engines and mileage
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86 c30 crew cab dually 454/400 4/6 drop SOLD 1-8-11 1981 chevy K10 short Bed Scottsdale SOLD 10-26-2020 67 GMC Stepside Straight six/3 on the tree "The Peach" 2020 Silverado Double Cab LT Z71 5.3 8 speed Daily Driver K10 build http://67-72chevytrucks.com/vboard/s...d.php?t=671934 The Peach build http://67-72chevytrucks.com/vboard/s...d.php?t=733903 |
05-13-2010, 07:07 PM | #16 |
Registered User
Join Date: Feb 2010
Location: Tony, WI
Posts: 69
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Re: engines and mileage
Damn 13 with a BBC?
I am running a 350 and i get 9-12MPG in a '86 C10 longbed |
05-13-2010, 07:20 PM | #17 |
Registered User
Join Date: Jun 2009
Location: Lawson Mo
Posts: 147
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Re: engines and mileage
My 2000 Sierra with the 5.3 and 3.73 gears averages 15 to 18 mpg.
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2006 Silverado 2500 HD |
05-13-2010, 07:21 PM | #18 |
6.0 powered square
Join Date: Feb 2008
Location: Mesquite texas
Posts: 3,459
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Re: engines and mileage
355 th350 and 3.73 I get 5 but thats in town with stop and go traffic I get up to 11 on high way going 50 , but I will have a 6.0 and 4l80 pretty soon
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Aaron 1980 c-10 short bed lowered, cammed 6.0, 4l80e 3600 stall, smp tune, wilwoods, and flames best time so far best et 7.86 @87 on motor 7.57 90 on a 75 shot Build http://67-72chevytrucks.com/vboard/s...d.php?t=283326 Last edited by flamingbig10; 05-13-2010 at 07:22 PM. |
05-13-2010, 07:24 PM | #19 |
Registered User
Join Date: Aug 2009
Location: Lambertville MI
Posts: 962
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Re: engines and mileage
man id kill for a bigblockwith 8 let alone 13! i got a 350/350 with 3.42s and im happy if i get ten.. then again, i drive the **** out of my truck.. but if i were you, id for sure go diesel.. awesome mileage and they still got some nuts. and if you turbo it, itll be better all the way around
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"I'll keep my guns, money, and freedom. You can keep the "change" |
05-13-2010, 07:59 PM | #20 |
Account Suspended
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Location: Where I come from, it's cornbread and chicken...
Posts: 3,122
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Re: engines and mileage
see sig
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05-13-2010, 08:40 PM | #21 |
Account Suspended
Join Date: Dec 2007
Location: Unnapreciative, Trollville
Posts: 2,079
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Re: engines and mileage
Dang. I'm going great then! I been getting 15-16mpg outa my 5000lbs 78 c20, 350/400. Maybe a lighter right foot would help....haha
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05-13-2010, 10:14 PM | #22 |
Registered User
Join Date: Dec 2009
Location: lindale,tx
Posts: 2,373
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Re: engines and mileage
YA i have a 85 burb with 3/4 ton axles with 4:10 gears a 700r4 and get 7. With quadrjunk. I dream about 13 MPG....
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82 c10 5.3/4l60 84 c20 5.3/sm465 85 chevy k10 suburban LQ4/4l60 91 chevy c10 suburban Lsa 5.3/4l60 2017 Silverado whipple 5.3 1964 Vw beetle 1974 vw beetle |
05-13-2010, 10:43 PM | #23 |
Registered User
Join Date: Feb 2010
Location: Morgan, MN
Posts: 19
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Re: engines and mileage
My '86 C10 longbed gets anywhere from 16-19mpg regularly and has seen 20mpg on a couple of long trips. Rebuilt stock 350 out of an '89 burb, rebuilt Q-jet and 700R4 with 3.42 gears. Not the fastest truck but quite pleased with the mileage.
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05-13-2010, 11:15 PM | #24 |
Navy Radioman Veteran
Join Date: Jul 2007
Location: Western Kentucky
Posts: 1,356
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Re: engines and mileage
... mine is a '76 454 with all the head work, 750 carb & a turbo 400.. 12-14 mpg highway.
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1987 Chevrolet R10 Silverado BBC Build thread - SOLD 1986 GMC Sierra Classic - SOLD 1957 Chevy Step Side Daily Driver; 2005 Chevrolet Silverado 4x4 Z71 Stepside - SOLD 2005 Chevrolet Tahoe Z71 |
05-13-2010, 11:49 PM | #25 |
TruckincrazY
Join Date: May 2004
Location: Haslet, TX
Posts: 493
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Re: engines and mileage
checked mine this evening, 12mpg. 350/700r4/3.73
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