Cam upgrade??

[turboedge]

Hi all! I have a 94 K1500 with a 5.7L, NV4500, 14-bolt-3.42 gear ratio, E-cab, stepside. It now has new top end gaskets and fuel pump and it runs much better than when I purchased it. I could not pass it up. I had been looking for one of these trucks for a while and when I found this one with it's unique-ish options and only 57k miles, I could not help myself. I am thinking about changing out the camshaft. When I had everything else apart I swapped the exhaust crossover to a JBA 2831SY. It is 2.25 into 3 and very smooth and nice looking. I bolted it to the original manifolds. FYI to anyone doing that, you will need a burr to modify the clamps slightly or it won't fit. That has a 3" cat, some pipe then a 3" glass-pack and finally goes up over and out the backside with 2.75" tube. I would have finished it with three inch, but the previous owner had put in what looked to be a factory stainless muffler out of a later model and it was nice smooth and pristine looking. So any thoughts on a proper cam for this engine? I checked when I had it apart, it's not tapped for a roller cam. I have no plans to replace the heads or exhaust manifolds. What is there is made for torque and I'm ok with that. I have a feeling though that there may be better cams if I'm not quite as emissions constrained as GM was. I also am not opposed to re-tuning. In fact I am a member of another group/project that has standalone EFI control and I'm thinking about gutting a spare ECU I have and making a PNP unit for the -92 auto and -95 manual trucks, but that's a whole other topic.

Thanks in advance for the recommendations! Let me know if I left out an important detail.

 

[turboedge]

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https://drive.google.com/file/d/1g9MFIppXPuegWz-Nacdae5pJEUn1gw2Z/view
Somebody should wash her.

 

[PlayingWithTBI]

I swapped the exhaust crossover to a JBA 2831SY. It is 2.25 into 3 and very smooth and nice looking. I bolted it to the original manifolds. FYI to anyone doing that, you will need a burr to modify the clamps slightly or it won't fit.

I used the same JBA "Y" pipe connected to Summit Racing shorty headers and a high flow 3" cat - didn't have any issues connecting it. Anyway, take a look at Lunati Voodoo cams like this one, I went with it and 1.6 roller rockers to get .466"/.484" lift.

https://www.summitracing.com/parts/lun-10120700lk

 

[GEO NEO]

Anyone else done any Camshaft Upgrades to a stock 5.7 ??

 

[Casey Price]

I used the same JBA "Y" pipe connected to Summit Racing shorty headers and a high flow 3" cat - didn't have any issues connecting it. Anyway, take a look at Lunati Voodoo cams like this one, I went with it and 1.6 roller rockers to get .466"/.484" lift.

https://www.summitracing.com/parts/lun-10120700lk

What do you think about this cam? Running MOD TBI all the bells and whistles, Vortec fuel pump, 64cc heads, 1.5 roller rockers and stock bottom end.
Lunati 10120702LK Lunati Voodoo Cam and Lifter Kits | Summit Racing

 

[PlayingWithTBI]

What do you think about this cam? Running MOD TBI all the bells and whistles, Vortec fuel pump, 64cc heads, 1.5 roller rockers and stock bottom end.

That cam will give you pretty close to what I get with 1.6 full roller rockers, you do get more duration though. I have the Summit Racing heads (162108) with 62 CC chambers, guide plates, and chromoly push rods, and bored 46mm TB (with ultimate mods) and Edelbrock 3704 manifold. I'm running the stock 61 LB/HR injectors with an 18LB spring set to 20PSI.At 5300RPM WOT in 2nd gear they're pretty close to 100% DC.

Back to the cam - when I was putting this together, I was worried I wouldn't pass emissions here in AZ so, I figured I could always go back to 1.5 rockers to pass, then switch again. Since then, I got it registered with historic vehicle plates and insurance to become exempt from emissions so, I never did have to take it in for a test. IMO your choice should work. I was reading about guys not liking the lifters Lunati supplies with their cams. I had one collapse and start tapping. It was worn down close to 3/32" IIRC (the cam was still good). I ordered a couple more from them and put it back together - so far so good! HTH

Don't forget to break it in properly, this is critical with a flat tappet cam!

 

[Casey Price]

That cam will give you pretty close to what I get with 1.6 full roller rockers, you do get more duration though. I have the Summit Racing heads (162108) with 62 CC chambers, guide plates, and chromoly push rods, and bored 64mm TB (with ultimate mods) and Edelbrock 3704 manifold. I'm running the stock 61 LB/HR injectors with an 18LB spring set to 20PSI.At 5300RPM WOT in 2nd gear they're pretty close to 100% DC.

Back to the cam - when I was putting this together, I was worried I wouldn't pass emissions here in AZ so, I figured I could always go back to 1.5 rockers to pass, then switch again. Since then, I got it registered with historic vehicle plates and insurance to become exempt from emissions so, I never did have to take it in for a test. IMO your choice should work. I was reading about guys not liking the lifters Lunati supplies with their cams. I had one collapse and start tapping. It was worn down close to 3/32" IIRC (the cam was still good). I ordered a couple more from them and put it back together - so far so good! HTH

Don't forget to break it in properly, this is critical with a flat tappet cam!

Your TB is that a punched out 454TB?

 

[PlayingWithTBI]

Your TB is that a punched out 454TB?

No, it's 46mm from 5.7L 42mm which flows 650CFM - good enough for 6000RPM. I have it on the Edelbrock 3704 with ports bored to 48mm.

https://www.ebay.com/itm/46mm-PORTE...837306?hash=item3d963196ba:g:mpwAAOSw2xRYWVJj

https://www.summitracing.com/parts/edl-3704

 

[PlayingWithTBI]

Ooops! I just reread my earlier post. I must be dyslexic, I typed 64mm instead of 46mm, sorry about that! I edited it.

 

[Casey Price]

Ooops! I just reread my earlier post. I must be dyslexic, I typed 64mm instead of 46mm, sorry about that! I edited it.

What are your thoughts on a 454 TB. Do you need the base for it to work? I found one and the guy wants $50 no base.

I've been tossing this cam around in my head also..
COMP Cams XFI 216/223 Hydraulic Flat Cam for Chevrolet Small Block