Chevy 350 MPG build

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Question:
IF you were to build a GM long block for efficiency (MPG/reliability) what would be a good combination? The 160hp/406lbft standard long block is what I'd be looking at.

Edelbrock Performer intake?
High flow water pump?
Roller rockers?
Lowest compression?
550-600cfm Carb?
Electric fan?
882 heads?
Stock cam?
MSD 6AL box?

Also, are there any decent torque converters for the 440 AT? Gotta keep the auto for the Mrs...
:cheers:
 
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Definitely not low compression, thats going the entirely wrong direction. Definitely keep a smaller carb, electric fan would be an improvement over a fixed blade fan, small AFR heads or anything with a modern, efficient chamber would be best. I like the dart iron eagle heads, same chamber as the aluminum heads but like 400 dollars cheaper. I would go with a small cam but not stock, thats not really good for anything.

BTW where did you get 160hp/406 ft-lbs from for a basic longblock, thats a lot of torque, id be suprised if you could get that much torque without moving the powerband higher a good bit.
 
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Definitely not low compression, thats going the entirely wrong direction. Definitely keep a smaller carb, electric fan would be an improvement over a fixed blade fan, small AFR heads or anything with a modern, efficient chamber would be best. I like the dart iron eagle heads, same chamber as the aluminum heads but like 400 dollars cheaper. I would go with a small cam but not stock, thats not really good for anything.

BTW where did you get 160hp/406 ft-lbs from for a basic longblock, thats a lot of torque, id be suprised if you could get that much torque without moving the powerband higher a good bit.

As for low compression I was meaning more like 9.5:1 or maybe 10:1 ratios. Sorry about that. Im used to my 383 thats at 14.1:1.
Forgot about Dart.
Local GMC dealer specs show the base 350 having 160/406. I too thought that was really high. I always thought it was like 160/250-ish...just googled some more and its supposed to me 160/260.
 
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Do you already have the motor? If not you can probably find something like a Gen II engine with harness and computer for under $2,000.
 
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That was another idea I was considering.
Currently Ive got three 350's, two 6.2's, and three 6.5's that I can buy at cost (all freshly rebuilt with 7yr 70k mile warranty).
:mad: Makes the choice just that much more difficult! Fortunately, the Mrs is tired of the lack of power. She loves diesels, and 350's:flipoff2: .
I'm more interested in trying to get a thread on efficient 350's since there are so many members running them out there.
 
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IMO Holley Projection = krap and old tech compared to the new Holley commander series or other programmable EFI systems.

I am doing Megasquirt on my V8 but if I had to do it over I'd probably go with a turn key kit like this and be done.

http://www.affordable-fuel-injection.com/chevy-tbi.htm

If your leaning( no pun) toward a carb
Do an ebay search on Motorcraft 2150 carbs.. there is a guy that promotes those for great mpg and simplicity and reliability. Theres a few guys running the 2100 and 2150 Motorcraft on their cruisers and say great mpg and will run on their side.

*update..here is the link and a good read*
http://cgi.ebay.com/ebaymotors/Moto...ryZ33550QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


IIRC
You said "the Mrs is tired of the lack of power".. better go EFI
 
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I bought a GM performance 350 HO crate motor and ran both a holly and then an edelbrok carb (both were aprox 600cfm with off-road kits). The motor was 330hp/350lbs and I was running 35" tires. The holly got about 9mpg and the edelbrok got about 11mpg. The holly had more power at WOT, the eddy was better in all other situations. I later upgraded to ramjet fuel injection and was getting about 14mpg with 38" tires. Go with fuel injection, if you can.
 
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Gen 3 LS1 5.7 out of a Camaro/Firebird. All aluminum and gets great mileage in those cars. Obviously expect quite a bit less if transplanted in a Cruiser, but still better than stock and better than any other SBC.
 
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Hey guys, Im VERY appreciating the feedback. BUT, I was looking to inquire what parts one would choose to develop (build) a gen I/II chevy 350 with MPG in mind. Anyone with enough $ could just go and buy a donor car and transplant it into an FJ60 series.

What I want to know is if you have a 350 gen I long block sitting in your garage what would you build it with for maximum reliability and fuel economy.

Just wanting to get this back on topic...
THANKS!
:beer:
 
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Ok...so you have a 5.7 long block and you want max reliability and fuel economy. The choice is clear.... fuel injection. I would suggect you rob parts of a 350 TBI motor(throttle body injection). Fuel Injection is hands down more reliable than a carb setup. 2nd point is that you're better off with one of the GM fuel injections systems due to the vast parts and knowledge base. 3rd.. if you want to run a carb, then I would go with a eldebrock performer intake, a very mild cam (like stock) and a Holley 600 vaccum secondary carb.

Reliable + Fuel Economy = Stock Engine
 
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one other point... you might look around for a used buick roadmaster or chev caprice with the 5.7 TBI engine. You can buy the entire car for a reasonable price. If you already have a long block and want to keep it simple then go the old school route with the 600 holley and performer intake.

I think the 350 GM TBI engines are very reliable (not great horsepower kings) but its nothing to get 150K plus miles on one.

Like I said before.... stock is reliable, pattern your parts around a stock setup. 9.25-1 or 9.5-1 compression. Stock type camshaft profile, along with what I said previously about the intake and fuel system.
 
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If you are going carb'd then you might as well go ahead and go with Vortec heads, like the 906 castings. These flow even better than the old school "double-hump" 300 hp 327 heads. Edelbrock makes a carb intake to go with those heads. You can pick up those heads relatively cheap. The best bet would be to buy a complete engine out of a 96 or newer truck, then just swap out the fuelie manifold for the carb'd one. Those are 4 bolt main, one piece rear main seal, and roller lifter engines.
 

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