Which motor should I go with?

[Smokejohnson]

Should I go with a 525hp LS 3 or a big block with roughly same hp?

[iowaboynca]

I wish I had this dilemma...
without knowing more, I would say the LS on the basis of less weight. but that's my $.02

[PurdueSD]

LS no brainer...

Big blocks sound so good though!

[Smokejohnson]

Was going with the LS untill I drove my buds 70 Chev it's got a 468 with a procharger. Man that thing sounded good.

[_Ogre]

you want to drive it or race it?
either suggestion screams 4 mpg

[Highsider]

Originally Posted by _Ogre

you want to drive it or race it?
either suggestion screams 4 mpg

A bit OT:
What do folks get with a little, mostly stock 350, HEI, Edelbrock manifold w/4bbl ?
I am happy when I get 10mpg on premium.

[_Ogre]

define stock? i have a stock gm ramjet 350 that gets 20 mpg

why do you run premium? premium fuel will typically get worse mileage than regular.
premium fuel is mainly for higher compression motors that have a destructive knock when run on regular
high compression motors typically are also high horse power, thus people equate more hp with premium fuel
premium fuel will actually decrease your hp

[Smokejohnson]

Truck mite see the track the odd weekend but mostly be street/show. I need to pull the trigger soon on the motor and trans so I can mock it up. Any thoughts on a auto trans?

[65Ch3v3LL3]

Run the LS3. You will get big block hp and tq but great fuel mileage too assuming you go with EFI. As for a trans I would either run a 4L80E or a 6L90E. The 6-speed auto is really a nice transmission. If you want to go manual just throw a T-56 or TR-6060 in there. For fuel just grab one of the new aftermarket under bed tanks and throw the new Aeromotive in tank fuel pump in it. It's a universal kit and will support up to 700hp for EFI. Its an easy install and you don't have to worry about baffling the tank or having fuel starvation problems.

[1project2many]

Hmmm....

You wouldn't choose a 1970's projection TV over a modern HD flat screen would you? Go with the LS engine!

[87Lowrider]

This is what I'm putting in my '57 Stepper. LS3 Connect and Cruise Kit.

http://www.chevroletperformance.com/...systems/#ls3_k

[sqrlnts]

Originally Posted by 87Lowrider

This is what I'm putting in my '57 Stepper. LS3 Connect and Cruise Kit.

http://www.chevroletperformance.com/...systems/#ls3_k

Those Connect n cruise packages look super clean, BUT $12K, is STEEP!! I would also recommend the LS motor, if you are up to the task of playing with wires.

[Speedbumpauto]

Nothin wrong with a big block!

[_Ogre]

Originally Posted by 87Lowrider

This is what I'm putting in my '57 Stepper. LS3 Connect and Cruise Kit.

my ramjet 350 is the early version of those.
best thing i could have done for my truk.
plug and play for sure
other than oil changes, i've done nothing to it

[Jmiller022]

Originally Posted by 87Lowrider

This is what I'm putting in my '57 Stepper. LS3 Connect and Cruise Kit.

http://www.chevroletperformance.com/...systems/#ls3_k

Id suggest getting the crate engine alone and then buying a 4L80e it will last alot longer than the 4l65e. just my .02!

either way itll be sweet

[Purcell69]

Originally Posted by Highsider

A bit OT:
What do folks get with a little, mostly stock 350, HEI, Edelbrock manifold w/4bbl ?
I am happy when I get 10mpg on premium.

Years ago, I built a 454 to tow my wife's horse trailer with her 1978 C10. As I recall, the heads were open chamber 019 casting oval ports. The cam was an Isky 268 duration and I had a Holley 750 cfm vacuum secondary on top of a Performer RPM. With the heaviest secondary diaphragm spring, that truck would get 12 MPG all day long, loaded or empty with a TH-400 and a 3.07 geared rear end, no premium required.

-Joe
Posted via Mobile Device

[sqrlnts]

Originally Posted by Highsider

A bit OT:
What do folks get with a little, mostly stock 350, HEI, Edelbrock manifold w/4bbl ?
I am happy when I get 10mpg on premium.

Just switched to that exact setup from a 2bbl. Initial results show 14.5 mpg with regular fuel, up from the previous 8.5mpg 2 barrel hog!

[Smokejohnson]

I made up my mind LS it is. Thanks for your help guys I will update my build when I get time to sit for more than 2 min's.

[mr48chev]

Great choice if the budget will support it.
I'd think seriously about setting the whole drivetrain up so that in the end it was effectively geared out where the rear tires meet the ground pretty well the same as a performance car that engine would come in. Meaning match your tire outside diameter and rear gears to emulate the gearing in a Z Camaro or Corvette that might have that engine/trans combo. That way you will have a pretty quick truck that will also handle serious road trips and pull decent fuel mileage.