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Old 12-18-2017, 04:37 PM   #1
ty_c
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5.7 Vortec basic upgrades

I am doing a semi-short term engine install in my new to me 1970 Jimmy. Using a 5.7 Vortec engine and trans out of a 99 Suburban denor car. Thing is I would like to do some basic upgrades on this engine while I am doing the swap. 255hp stock from the 5.7. Thinking I can get to 320+ with a cam, black bear tune, long tube headers, and k&n filter. Might need some light head work dependent on cam choice. (springs, threaded studs, etc)

There seems to be the super basic bolt on guys who get 20-30hp increases and then much harder core guys pushing 400s. Not much inbetween I think I would like to stay out of the lower end (unless I really need more compression) and keep my budget on this to $500-1000. Unless I spring for a Weiand.

Torque is actually more important to me as I am looking for drivability but thought the hp reference might be more useful.

First thought was to contact Black Bear and ask them if they have a recommendation based on my needs.

All suggestions will be appreciated even if they are not taken.
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Old 12-18-2017, 05:27 PM   #2
hemi43
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Re: 5.7 Vortec basic upgrades

Quote:
Originally Posted by ty_c View Post
I am doing a semi-short term engine install in my new to me 1970 Jimmy. Using a 5.7 Vortec engine and trans out of a 99 Suburban denor car. Thing is I would like to do some basic upgrades on this engine while I am doing the swap. 255hp stock from the 5.7. Thinking I can get to 320+ with a cam, black bear tune, long tube headers, and k&n filter. Might need some light head work dependent on cam choice. (springs, threaded studs, etc)

There seems to be the super basic bolt on guys who get 20-30hp increases and then much harder core guys pushing 400s. Not much inbetween I think I would like to stay out of the lower end (unless I really need more compression) and keep my budget on this to $500-1000. Unless I spring for a Weiand.

Torque is actually more important to me as I am looking for drivability but thought the hp reference might be more useful.

First thought was to contact Black Bear and ask them if they have a recommendation based on my needs.

All suggestions will be appreciated even if they are not taken.
I have a stock 5.3 rated with less HP as that 5.7, and to be honest, any more HP will just be wasted. You start hitting 300+ HP and that Jimmy will be a handful. Unless yours is a 2WD, I would leave the engine stock.
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Old 12-18-2017, 11:10 PM   #3
ty_c
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Re: 5.7 Vortec basic upgrades

Thanks for the advise. I guess I just don’t want to get it all dropped in and say “I shoulda” after driving it for a while. My guess is I will never say “that’s just too much power” lol. I’m not looking to go over the top just bring out a few more hp while they are easy to get
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Old 12-18-2017, 11:42 PM   #4
truckster
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Re: 5.7 Vortec basic upgrades

The RamJet 350 / HT 383 cam will wake that engine up a bit. I'm running HEI and a Quadrajet, but mine should be putting out about 330 HP and 400 ft/lbs torque.

As far as mods, my machinist put in springs from a regular old 350. He said the spring height was OK, but the Vortec springs are lighter (less spring pressure).
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Old 01-04-2018, 03:34 AM   #5
87Skier
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Re: 5.7 Vortec basic upgrades

Did something similar to this. Planned on putting a different engine later on down the road and wanted something to drive around now.

Bought a 97 Suburban to part out.
I put a HEI distributor on it, carb manifold, Quadrajet, headers, and exhaust (most of the exhaust system was missing anyway).

Even with the 3.07 gears, ancient Turbo 350, and an engine that had 240,000 miles it felt pretty good.
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