Best economy/performance Engine for

[nouveau_retro51]

Steve: I spent 3 years hunting for a classic chevy truck that I wanted to have modern driving comforts (inside, under-the-hood and underneath) around town and on the highway including fuel economy. I found a five-window 1951 3100 with very little rust that some kids had tried to supe up and then gave up. They put in tint windows all around, AC, bucket seats, power windows, modern heater/defrost, camaro frame with undercoating and camaro rearend. Someone else wanted the ridiculous 450 engine they put, so I let them have it and bought the rest. I have someone who has a small junkyard of old trucks that he works on where it currently resides. He has a 305 with 700R4 transmission out of a 1985 Suburban (4 barrel, 2WD rear)that he says started right up with no smoke that he bought to put into an old truck. I am not very mechanically inclined but want to learn more and I have to make a decision right now. I have limited funds and need to get the truck drivable and on the road (paint/finish work later) but have to make an engine decision now. I could have him put that engine/transmission in and go with it as is. I plan to have Auto Zone or Advanced Auto swap out a remanufacture for $700 more and use synthetic oil from day one. My questions are mainly about fuel economy/performance. My original plan was for a 305 with 200RF transmission to get decent fuel economy (and a simpler transmission). Will the 700 R4 reduce the fuel economy and what might I expect it to deliver mpg mated with a remanufactured 305 in the truck as I have it configured? (This is important because I plan to drive it NC to Maine once a year loaded--moving stuff in addition to other highway trips.) I have scoured the net looking for performance comparisons for older engines and have had no luck--only new trucks and overall fuel economy tips. My plan is to really drive rather than show this truck, though she should be quite pretty and very comfortable when I am done. Has anyone done anything like this who could tell me the relative merits of the two transmissions mated with the 305? Or are there other engine/transmission configurations I might consider?

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[vwnate1]

RE: Best economy/performance Engine

The 700R4 tranny is sturdier , both will give you similar economy as they have lockup torque converters .

Small diameter tires like you have will make fuel milage suffer . it's wise to only use LT (truck) rater tires on this vehicle , esp. since you want to drive high speeds and haul with it .

High ratio (low numerically) rear ends will also increase fuel milage

Many ways to get power out of a Chevy 350 , many are now making them into 383 strokers...

-Nate

 

[nouveau_retro51]

RE: Best economy/performance Engine

Nate, Thanks for the help--I will follow your tire advise. I did more research today and found what looks like a good deal. For $1,500 a local junk yard will sell me a 4.3L V6 Vortex with wiring harness and computer with a 4L60 transmission (with compressor for my A/C) from a 2000 Astrovan that got rear-ended. It has been in their yard for a year and a half, so the thing was probably only on the road about 3 years. Will this engine/tranny combo fit OK with my 1951, 3100 with Camaro subframe and Camaro rear end? What do you think of this? Do you see problems?

Steve

 

[vwnate1]

RE: Hot Rods

Well Steve ;

Every time I look at or get roped into working on , a hot rod I see problems , it usually take the builder three whole projects before they figure out how to do it remotely correctly so I avoid them as much as I can .

If you can find a local guy who's been down this raod then yes , it'll go right in but your chassis is allready rather old tech IMO .

If I wanted the hassle of a V-ate powered AD truck , I'd save time and $ by buying an allready finished and running one for under $5,000
as you're going to put WAY more than that into your truck plus sweat equity . cool if you want to play truck builder for the next three years but you said you need it to run and be a work truck soon...

Sorry to be such a downer buddy .

I run a farily stock '49 with 235 and 12 volts , all else is stock and it runs 65 ~ 70 MPH all day long with the Patric's 3.55 gears in the Torque Tube and tall radial D rated tries , tows too .

-Nate