papa

I have a '53 chevy 1/2 ton that has a well worn 350 SB. At the expense of a little HP, I'd like to lighten the front end a tad, and slip in a lighter, more fuel efficient V6. So, what's the preferred choice among GM V6'es that'll bolt-up to the existing 700R4 trans the rig has now? I plan to buy a complete donor car/pu to take advantage of EFI (be it MPFI or TBI, or??).

I'm an older, experienced wrench (and fabricator), so any required welding (exhaust, front mounts?.. ect) won't pose any problems.

What say the experts?

Street Lethal

iTrader: (16)

^ Syclone / Typhoon 4.3 Turbo w/out a doubt, Click Here....

z28monster

iTrader: (1)

id have to agree with an old heavy truck like that i wouldnt go any smaller then a 4.3... and the 4.3 will drop right in and bolt to the tranny thats in the truck right now with out any probs at all.

ljnowell

the 4.3 would probably accept all of the accesories that are bolted to the 350 also. Not a bad idea. Although, a mild 350, with a 700r4, tuned right can get similar mileage, I dont think its a worth while swap, IMO.

papa

Appreciate the insight, all.

Further,..

What do I search for in a donor? And specific year(s) better suited than others?

five7kid

iTrader: (14)

You're stretching the limit for being 3rd gen related on this Board. I don't see any benefit to 3rd gen owners for this topic on the Engine Swap forum.

I'm moving this to the V6 forum, and will let the moderators there decide if it has any merit for members on that forum.

papa

I apologize if my posts seemed inapproapriate for this site. My intent was to gain knowledge in later GM V6'es, describe intended usage, and learn overall compatibility with my existing hardware. Yes, I considered the 'V6' forum (and likely more approapriate), but chose the 'engine swap' forum thinking it was better align with my overall query. Again, my apologizes.

noahTHEpurdy

iTrader: (1)

Don't mind the mods. Ever since the site was bought out, they've been overly ****.

I'd say a mild 350 would be your best bet in a heavy truck like that, otherwise I'd go for the 4.3, as it's just a SBC with two cylinders lopped off.

firstfirebird

iTrader: (3)

You have to choose a 90* v6 to bolt to the trans. The 60* V6's use the small corperate pattern.


A turbo 3.8 would be cool to see in something like that.


If you were willing to swap transmissions, I would say the 3900 or the 3.6DOHC.


How much does the truck weigh?

five7kid

iTrader: (14)

Cute.

bl85c

iTrader: (2)

I tend to agree with five7kid, this really isn't 3rd gen related. But on the other hand...
Grab a 4.3 out of a blazer if you want to go the v6 route, you'll need the extra displacement. Otherwise you should stick with a 305 or 350. A hefty truck like that would probably get better mileage with a torqey v8 than a v6.

noahTHEpurdy

iTrader: (1)

I thought so.

zs&tas

when it comes to a thirdgen im a big v6 fan but trucks do really need a v8 - the latter v8s, i had a 95 transam, can be very fuel effiecent with all the electronics, but you can blow it all pullin out hard just once its all down to the weight of your foot ;-)
if not i second the 4.3.

papa

I've not had this rig across the scales, so I can't quote exact numbers. Another site quotes factory stock at 2575 lbs, but I suspect this example weights a little more,.. likely closer to 3000 lbs.

firstfirebird

iTrader: (3)

Well seeing the thirdgens weigh more, you can expect a little more performance.

As mentioned before, since you have the 90* bellhousing pattern, it's going to be easier for you to stick with the 90* engines. This would be either a 4.3 or a 3.8, both came in turbo versions and would scoot your truck nicely. I had a 4.3 N/A in one of my old trucks (86 1500 short bed) and it lasted just over 289,000 miles.

bl85c

iTrader: (2)

I'd be suprised if it weighed less than 3000lbs.