Oh man Gas prices will kill me..which engine?

[iluvmy72]

I have the original 350 block to rebuild, or I also have the 4.3 liter engine with all eletric or I also have the old rocket 350 high nickle grade block from 69. I'm tempted to do the olds, but the 4.3 talks to me to save fuel. What shal I do?

[etg]

I asked myself the same question when I started my build. Pretty much it boils down to what you want your truck to be once its done. Power = bad mileage
and usually Good Mileage = Lower power. For a daily driver pick a mileage build with a milder engine. I picked a 350 with a mild build and am getting a good gas saving tranny (700R4). Just think ahead a lil bit to what you want the final product to be like.

[mrein3]

Originally Posted by iluvmy72

I have the original 350 block to rebuild, or I also have the 4.3 liter engine with all eletric or I also have the old rocket 350 high nickle grade block from 69. I'm tempted to do the olds, but the 4.3 talks to me to save fuel. What shal I do?

Go crazy and build a fire breathing dragon for your truck. Drive it on weekends.
Then get a Ford Escort, 1994 or 1995 with a 5-speed and 1.9l engine to drive every day. They cost under $1500, you can't kill them, and they get 35+ mpg.

[67chevemall]

Originally Posted by mrein3

Go crazy and build a fire breathing dragon for your truck. Drive it on weekends.
Then get a Ford Escort, 1994 or 1995 with a 5-speed and 1.9l engine to drive every day. They cost under $1500, you can't kill them, and they get 35+ mpg.

My crazy sister bought a 90 escort new and is still driving it.
You just can't go wrong there.

[mrein3]

Originally Posted by GMC AMI

Just kidding but many people seem to overlook the fact that driving today on American roads is the most risk the average person takes on a average day. IMHO I will stick to a more costly truck ride because it is cheaper insurance if you value your health and life more than saving MPG. Not to mention double tag fees and double insurance bills for two rigs on the road. You must have more money than me, LOL!

I hear ya but remember my Escort was designed with crash zones, 3-point seat belts, and air bags. My truck has a lap belt. I am driving the safest car I own.

Recently there was a fatal on I-94 NW of the twin cities. A full-sized CK pick-up was hit head on by a Chevy Cavilier. The couple that were in the Cavilier are alive. The guy in the full-sized pick-up didn't make it.

My poor little 1994 Escort that I bought new and now has 254,5xx miles on it is just about beyond its useful life. My daughter is 4. There is a fighting chance that she will some time drive the next car I buy. I'm not looking for a big, heavy, crappy gas mileage tank. I'm looking for an agile, American made, fuel efficient car that is highly ranked in crash tests. If I own my truck 12 years from now the only time I'll let her drive it is if I'm riding shotgun.

[68 short step]

ls1 your truck and get 18 to 25 ( or so) MPG

[67ChevyRedneck]

There was a member here with a 67. with a 4.3L with a 4L60E transmission and he was getting 18-19 mpg on the highway. Probably 15 city. I think his board name was Scooter67, but I think the truck was sold to another memember.

Daily driver: 4.3

Weekend cruiser..... BIG BLOCK

[Longhorn Man]

As far as MPG, I've had 2 350 small blocks, one old worn stock one, one fresh cammed out one...turned old and decrepid after some time.... then I had a 400 small block in good condition, and now this caddy 500..... they ALL got 10 - 12 MPG

[lilred67]

my '67 250 c.i. six cylinder with 3.73's gets 10 mpg..........
i could of had a v-8!!!!!and get the same milage

[TP from Cntl PA]

As far as gas engines go in these trucks, the old tired 350 which was 100% as it left the factory got the best fuel mileage wise.

I imagine with an OD it was have done really well considering the size.

[Longhorn Man]

Not just a V-8... A 500 CID big block.

[shelby987]

My stock internal 250ci with a 4bbl intake/450cfm carb, dual headers, and a set of 4.56's in the rear gets 14mpg whether I am doing 70mph on the highway or cruising around town......thinking about looking into an overdrive unit behind the transfer case down the road.

[iluvmy72]

shelby.....no offense but I find your current milage and configuration with it is a bit hard to believe.

[shelby987]

Originally Posted by iluvmy72

shelby.....no offense but I find your current milage and configuration with it is a bit hard to believe.

I can understand anyone's dis-belief, when I got the truck almost a year ago, I got 12~13mpg on the highway if I kept it just below 65mph (265/75R16 tires are slightly larger than stock, so I figure its just about 70mph). My around town driving on the 8 mile drive to and from work was anywhere from 11~12mpg. Ever since I put my 'economaster' carb on there along with my headers, I have gone through 4 tanks, each on sitting right below 13.9mpg....maybe the economaster carb was worth it!
Future plans are to swap in 4.10's, the use of acetone just to see what the hype is all about, and slightly taller (and less bald) tires.
Just as a side bar, with the torque this engine put out stock it was fun, with the secondaries wide open on the highway this truck is FAR from underpowered!

[67ChevyRedneck]

iluvmy 72:

I have a stock 350 (one of them crappy late 70's weak 180 horsepower?) with a 700R4, 3.73 rear end. If I kept the truck at about 60mph I could get almost 17 mpg highway. If I pushed it to 75mph (which it easily cruised at with the 700R4) my mpg dropped to a little below 16. I consistently got about 13-14 straight city driving.

When the truck had the I-6 and 3spd I got about 11mpg, speed and type of driving didn't seem to have any effect.

Maybe the real question is which transmission and which rear end gear to use?

[Longhorn Man]

It's the 4.10's that I hate. I have a 3.54 Dana rear heading here next weekend, should make freeway cruising MUCH nicer.
Maybe I'll check my MPG again after that.

[iluvmy72]

Hey longhorn.....where did you get that DANA?

[iluvmy72]

OK I think I am shooting for this configuration.....I will put in the 69 Olds Rocket 350(light and strong) and see if I can get a bell housing adapter to work with a 700 r4 from my Astro van and move the rebuilt TBI stuff to the Olds. I think this will be my best option in terms of power and milage. I am not going to use the old 350. I might just rebuild it and sell it to a ebayer.

[Sequoyah]

To the OP...just buy a used Honda or Toyota and build the truck how you want it.


--->owns a 91' Honda CRX that averages 35-40 mpg depending on how I drive it.

/puts flame suit on

[iluvmy72]

That would mean I might sell my old TH350 tranny. It was rebuilt with only 150 miles on it before I moved out of state. It also has a high performance shift kit. Cost me 1400 bucks to have it rebuilt. Though it has been sitting for 2 years it's still probably good.

[Longhorn Man]

I got the dana from a member here, was on the parts board.

the only adapter you should consider is from trans adapt. This acording to all the guys on the caddy board I frequent.
Personally, I'd just sell the 700 R4 and pick up a 200 4R, most of them already have a daul bolt pattern bellhousing and has better gearing all around.

[bryanw1968]

I think the main problem is that you're trying to drive something old and heavy as a daily driver AND get decent mileage. It is what it is. I agree, make it nasty and drive it on the w/e's.

[mark69]

I've got a 93 nissan std cab short bed 4cyl auto that only gets 15mpg (epa is 18-20) Thats why I got my V8.

[70heavyhalf]

my mom gets 16-18 mpg in her 68' camaro with a 350, th400, and 3.08 but its lighter then a pick up.

it gets better gas milege then our 04 f150

darin
________________
70 c/10 250/3 on tree/3.73 being rebuilt

[Longhorn Man]

how much lighter is this camaro? Most muscle cars were 3500 - 4000 pounds... like the typical small block truck.