Cam upgrade for 1997 Vortec 5.7 L31 with 210k

[97K1500Silverado]

Hi All,
I Have a 1997 K1500 with Vortec 350. Engine runs excellent with 210k on the clock. Was thinking of doing a winter project and putting in a performance cam. I do get some tapping noise only when temps are below freezing but goes away after a minute.

I live at 7,000 feet elevation so I'm already down 20% hp and torque when compared to sea level.

1.Is this worth it or will I not notice much of a difference?
2. Do I need to get computer reprogrammed after cam swap or it is ok since its been tuned already by Black Bear Performance?
3. Do I need to replace lifters pushrods and springs as well? If so what do you all recommend?
4. What cam do you all recommend?
https://www.summitracing.com/parts/nal-14097395/

Maybe base it off parts in this article from FourWheeler magazine?
https://www.fourwheeler.com/how-to/...6-to-2000-350ci-chevy-vortec-5700-v-8-engine/

Truck specs:
1997 K1500 Ext cab short bed
4L60e transmission (original still going strong!) New oversized TCC lockup valve and TCI Deep aluminum pan
3:73 gears with F44 package semi floating rear-end 14 bolt
Exhaust: Shorty headers, Flowmaster headpipes with high flow catalytic converters, dual in / out Flowmaster muffler true dual exhaust 2.25"
Blackbear tuned stock computer.
Intake is stock except for K&N filter

Heres a video of my truck

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[Erik the Awful]

I do get some tapping noise only when temps are below freezing but goes away after a minute.

Piston slap?

If you're planning on taking the heads off, go ahead and replace the springs. A broken spring can trash a motor. I like LS2/LS6 valvesprings and Comp Cams 787-16 retainers.
https://www.summitracing.com/parts/nal-19420455 or https://www.summitracing.com/parts/sum-174002
https://www.summitracing.com/parts/cca-787-16

I would take the time to get a re-tune.

4. What cam do you all recommend?
https://www.summitracing.com/parts/nal-14097395/

Not that cam. Those look like stock specs. Why bother buying that cam if the stock one is fine? With what you already have, I'd consider the "GM Hot Cam".
https://www.summitracing.com/parts/nal-14097395

 

[L31MaxExpress]

GM SPO 357HP 350 crate engine cam is my go to cam now. 215/223 @ 0.050, .473 lift, 108 LSA. Its a baby hotcam designed for a L31. With its shorter duration and tighter LSA makes noticeably more low-end torque than the LT4 hotcam.

Price has recently gotten a bit steeper than it was is the only downside. But I like the OEM engineering put into it and the fact it is a billet steel cam rather than a cheaper and failure prone cast core like the cheap comp/lunati cams.

I like the 787 retainer and beehive spring upgrade as well. I use Pac1218s myself rather than the LS2/LS6 springs.

I would advance that cam 4° to put it on a 105 ICL and use 1.6 full roller rockers. Drill the pushrod holes out to 1/2". Then use the 0.016" rubber embossed steel shim head gaskets to increase the compression ratio and make the quench distance more ideal.

https://www.summitracing.com/parts/nal-12677151

A guy I know just put this cam in a L31 along with AFR Vortec heads. Had shorty headers and put a mandrel bent dual 3" exhaust with bullets turned down at the rear axle. His is an 8 lug 3/4 ton with a 4L80E and a 3.73 geared 9.5 SF. Truck sounds great even on the stock tune but he has a dyno tune scheduled to wake it up the way it should run. My guess is 300+ RWHP.

 

[97K1500Silverado]

GM SPO 357HP 350 crate engine cam is my go to cam now. 215/223 @ 0.050, .473 lift, 108 LSA. Its a baby hotcam designed for a L31. With its shorter duration and tighter LSA makes noticeably more low-end torque than the LT4 hotcam.

Price has recently gotten a bit steeper than it was is the only downside. But I like the OEM engineering put into it and the fact it is a billet steel cam rather than a cheaper and failure prone cast core like the cheap comp/lunati cams.

I like the 787 retainer and beehive spring upgrade as well. I use Pac1218s myself rather than the LS2/LS6 springs.

I would advance that cam 4° to put it on a 105 ICL and use 1.6 full roller rockers. Drill the pushrod holes out to 1/2". Then use the 0.016" rubber embossed steel shim head gaskets to increase the compression ratio and make the quench distance more ideal.

https://www.summitracing.com/parts/nal-12677151

A guy I know just put this cam in a L31 along with AFR Vortec heads. Had shorty headers and put a mandrel bent dual 3" exhaust with bullets turned down at the rear axle. His is an 8 lug 3/4 ton with a 4L80E and a 3.73 geared 9.5 SF. Truck sounds great even on the stock tune but he has a dyno tune scheduled to wake it up the way it should run. My guess is 300+ RWHP.

Thanks for the detailed reply. If I don't want to remove the heads can i just install the cam, springs and do i need to change the rockers?

Guessing my 210k 4l60e may give up the ghost putting more hp and tq through it.

 

[L31MaxExpress]

Thanks for the detailed reply. If I don't want to remove the heads can i just install the cam, springs and do i need to change the rockers?

Guessing my 210k 4l60e may give up the ghost putting more hp and tq through it.

You could just swap the springs and retainers on the engine however I find it less labor intensive to pull the heads. Get a pair of headstands and good speing compressor that holds the valve and depresses the retainer at the same time. At 210K I would probably get a valve job done at the same time.

4L60E may be on borrowed time amyway. Never had one make it past 40K miles in my Express van. The stock one died at 38K and the 4L65E spec rebuild with good parts died after 40K at 78K. Torque of the 350 and the weight of the van just killed them.

 

[Erik the Awful]

Get a pair of headstands and good speing compressor that holds the valve and depresses the retainer at the same time.

I lay the head on a 2x8 with a rolled up sock under the valve and use a lever-style valvespring compressor. It's less effective on the narrower beehive valve retainers.

I have a couple of other valvespring compressors, and they're awful fiddly. If you get one of the compressors that holds the valve, spend the money on a good one. The cheap ones are garbage. My Harbor Freight compressor needs re-straightening after three or four valves.

 

[97K1500Silverado]

Piston slap?

If you're planning on taking the heads off, go ahead and replace the springs. A broken spring can trash a motor. I like LS2/LS6 valvesprings and Comp Cams 787-16 retainers.
https://www.summitracing.com/parts/nal-19420455 or https://www.summitracing.com/parts/sum-174002
https://www.summitracing.com/parts/cca-787-16

I would take the time to get a re-tune.


Not that cam. Those look like stock specs. Why bother buying that cam if the stock one is fine? With what you already have, I'd consider the "GM Hot Cam".
https://www.summitracing.com/parts/nal-14097395

Link to “GM Hot Cam” ? The above link is to the cam I was initially looking at.

 

[Schurkey]

https://www.summitracing.com/parts/nal-24502586

Price has gone up nearly $200 recently.

 

[1ton-o-fun]

Wow, that's pricey! Wonder why the hike?

 

[Schurkey]

Cam cores are getting scarce. Howards Cams sent out a notice on this.

Expect the same sort of increase on lifters, too.