What type of kit should I use to rebuild my 5.7 K1500, if I also want more power and torque? MPG doesn’t matter.
Don’t use a kit, buy a crate motor with the HP you want. Shop Jegs or Summit or even Chevrolet itself. You’ll get an engine that is ready to drop in rather than waiting weeks for all the machine work your engine will require before you even install the parts for your “kit.”
A very popular upgrade is to buy a 383 crate motor. That is a 350 with small overbore and a longer stroke crankshaft. This can easily double horsepower and boost torque by 50%.
Keep in mind, it isn’t just the engine that needs upgrading. If you want to double your HP, you need to double the air and fuel supply for the engine and improve the exhaust. That means your 2 barrel throttle body won’t cut it anymore. Crate engines can be had from Chevy complete with new fuel injection and the electronics to drive it. That single exhaust needs to go bye-bye as well. New fuel pump and lines will be needed to fuel it.
And don’t forget the transmission! More torque means an improved 700R4 will be required to transfer that power and likely a re-built transfer case as well. And 21 year old differentials might need a re-fresh.
This WILL be expensive and it WILL take significant mechanical and electrical knowledge to pull this off. Good Luck
I vote for a 6.0 swap from a wrecking yard. I’ve seen several online for sale with low mileage pulled out of wrecked vehicles. Complete engines with the wiring harness. I believe they were priced around $3-$4k.
That’s a good motor to work with b/c there’s probably a lot of performance parts available for it. Suggest to google “hot rod magazine chevy 5.7 L”, you may get some good info from links to articles there. To increase hp and torque you’ll have to do some of these
- increase displacement
- increase compression
- increase intake airflow and exhaust outflow rates
- change the valve timing curve
So you are looking at some combo of increasing cylinder bore diameter, longer piston stroke, higher compression head, camshaft changes, turbo/super-charger, exhaust headers, etc. Take a look at what other folks have to say of course, but it seems a pretty common thing for hot rod diy’ers to change the camshaft as a way to get started on something like this. If the current config isn’t a roller cam, consider a change to a roller cam, which means new lifters etc too. Beyond that, to get maximum bang for the buck a turbo-charger is probably your best bet, if you can find a vender that makes a kit that fits the application Best of luck…
p.s. another idea, surf over to summit racing and see what kind of stuff they have their for that engine. use the search feature at the top right “search make/engine”. I’m not familiar w/that engine particulars but I found one chevy v8 5.7L engine listed under “chevy big block W engines”. This might prove expensive, I see some of the STS turbo kits are in the $7k range.
One that meets the emission sticker under the hood for the year of the vehicle.
With OBDII, there’s not much you can do in that respect and still be legal.
Now if you’re talking about a hack job to gain more power?
The skies the limit!
Until the checkbook hits its own limit.
I would go with an LS swap… Fuel injected, emissions legal, more power across the board excellent driveability. You never mentioned your budget however… Biggest bang for the buck would be an LS swap of some type so I’m with @Scrapyard_John on this one. There are ways to find them cheaper as I have seen them in U-Pull-It yards for much less, but its almost 2x the work, but personally I’m OK with that. The LS is a popular engine swap these days and for very good reason, this is also the reason for its cost as well.
An LS swap - 6.2 liter - would be my preference as well but re-read the OP’s post. If you have to ask the question the OP did, how capable do you think the OP is?
A 1998 would have multiport injection, it’s got the LT-1 derived 350. The TBI version was gone by 1996.
Just looked it up… the heads were LT-1 derived but the engine wasn’t an LT-1 with reverse cooling.
My bad on the throttle body FI, though!
Ah, well, I was just dreaming anyway. I’d like to swap the 4.8 in my Sierra for a 6.0. I only get 15-16 mpg anyway with the 4.8. I imagine the 6.0 would get 13-14 mpg in a half ton like mine. But with a lot more power. Would be a pretty easy swap on my truck. But I’ll probably never do it.