My turn, Camshaft suggestion
Feb 23, 2023 | 05:12 PM
#61
TECH Apprentice
Joined: Jun 2011
Posts: 320
Likes: 157
Bought the heads. Found what I thought was a good deal on a set of 243s. A set of remanned, ready to go 243s with a 3 angle valve job for $750 OBO. I was gonna make an offer on em, and asked the seller about milling. He said if I was willing to wait an extra day to have em shipped, they would mill em for no extra charge. If they are going to be that cool, I just went and bought em without trying to haggle. Going to get em down to 61cc.
Ebay seller teauran_0
Storefront: TRP Race parts
I still need a few things before I can do this package, but not much. I think injectors, head gaskets, a bolt to install the crank pulley, and probably a few more things. I'm hoping within a few weeks I'll get a good block of time to go and do the work.
Ebay seller teauran_0
Storefront: TRP Race parts
I still need a few things before I can do this package, but not much. I think injectors, head gaskets, a bolt to install the crank pulley, and probably a few more things. I'm hoping within a few weeks I'll get a good block of time to go and do the work.
You won't need injectors if your 4.8L is 2001+. Your current ones are the same as the LQ9 6.0L and will easily support 360hp unless your running something other than E10.
Feb 23, 2023 | 05:38 PM
#62
Thread Starter
Joined: Jul 2007
Posts: 870
Likes: 247
From: San Antonio, TX
I need to figure out which head gasket to use, and if there is anything else I should consider or definitely do while I do: heads, cam, aluminum radiator, TBSS intake, and tune. I do want to do a slight port (clean up) and polish on the heads first. Should make for a good time.
Feb 24, 2023 | 11:57 AM
#64
LS1Tech Sponsor
Joined: Jan 2008
Posts: 466
Likes: 250
From: Ohio, Georgia, Nevada, Texas
@adriver,
It sounds like you have your plan set and are moving forward toward your goals. If you have the rails and injectors from the NNBS intake go with those. The injectors should be a minimum of 30 lb./hr. Already having the adapters for the stock injector harness makes the swap easier. One thing to remember about the NNBS fuel rails is they are set up for a returnless system. The stock 2002 LR4 is a return-style system. Modifying the NNBS rails and fitting a Corvette-style regulator can take care of that.
Regarding head gaskets. We would opt for some .040" Cometic head gaskets for the compression bump. With 61cc heads that should bump compression from the stock 9.4:1 to right around 9.8:1. The added benefit is reducing the quench distance into the optimal range. This creates a more efficient combustion cycle and reduces the chance of detonation.
It seems the dreaded "while I'm in there" is creeping up on you. You would want the recommended springs for the cam you went with and some Chromoly pushrods. Being that you're having the heads milled we would highly recommend checking the pushrod length before purchasing pushrods. A pushrod length checker is a good tool to keep in the toolbox. We recommend going with a minimum of a 5/16 Chromoly pushrod with a .080" wall. You can typically find a set of 16 for around $100. We'd also look at replacing the lifters with some of our SUM-HT217-16 Morel 7717 drop-in lifters. It's a good idea to replace the trays at the same time so we offer them in a lifter and tray kit. A new LS2 timing chain wouldn't be a bad idea either. The list could go on and on but these are the core things we look at other than the required gaskets and seals needed.
It sounds like you have your plan set and are moving forward toward your goals. If you have the rails and injectors from the NNBS intake go with those. The injectors should be a minimum of 30 lb./hr. Already having the adapters for the stock injector harness makes the swap easier. One thing to remember about the NNBS fuel rails is they are set up for a returnless system. The stock 2002 LR4 is a return-style system. Modifying the NNBS rails and fitting a Corvette-style regulator can take care of that.
Regarding head gaskets. We would opt for some .040" Cometic head gaskets for the compression bump. With 61cc heads that should bump compression from the stock 9.4:1 to right around 9.8:1. The added benefit is reducing the quench distance into the optimal range. This creates a more efficient combustion cycle and reduces the chance of detonation.
It seems the dreaded "while I'm in there" is creeping up on you. You would want the recommended springs for the cam you went with and some Chromoly pushrods. Being that you're having the heads milled we would highly recommend checking the pushrod length before purchasing pushrods. A pushrod length checker is a good tool to keep in the toolbox. We recommend going with a minimum of a 5/16 Chromoly pushrod with a .080" wall. You can typically find a set of 16 for around $100. We'd also look at replacing the lifters with some of our SUM-HT217-16 Morel 7717 drop-in lifters. It's a good idea to replace the trays at the same time so we offer them in a lifter and tray kit. A new LS2 timing chain wouldn't be a bad idea either. The list could go on and on but these are the core things we look at other than the required gaskets and seals needed.
Feb 24, 2023 | 01:03 PM
#65
Thread Starter
Joined: Jul 2007
Posts: 870
Likes: 247
From: San Antonio, TX
I should be good on the TBSS intake.
I bought a cam kit, and it came with springs and a gasket kit. I will put in a new thermostat and gaskets while I'm in there, and doing the radiator and coolant any ways, (mostly because I know I have a leak).
I was going to wait until I got the heads to figure out the best sized head gasket. I do know I need lifters, trays, head gaskets. It's simple to some, but I overlooked that push rod length. Sounds like I can't figure that out, until the heads are installed. That definitely helps me plan the work, knowing I will have to get the heads in before I can figure that out, and then order them.
I know I've read about the LS2 timing chain before. I'll make it easy, and just put that in the cart.
I bought a cam kit, and it came with springs and a gasket kit. I will put in a new thermostat and gaskets while I'm in there, and doing the radiator and coolant any ways, (mostly because I know I have a leak).
I was going to wait until I got the heads to figure out the best sized head gasket. I do know I need lifters, trays, head gaskets. It's simple to some, but I overlooked that push rod length. Sounds like I can't figure that out, until the heads are installed. That definitely helps me plan the work, knowing I will have to get the heads in before I can figure that out, and then order them.
I know I've read about the LS2 timing chain before. I'll make it easy, and just put that in the cart.
Mar 5, 2023 | 09:04 AM
#66
TECH Enthusiast
Joined: Oct 2006
Posts: 642
Likes: 21
From: Euless, TX
@adriver,
Thanks for getting us more info on the 5.3. Since it is a bare block, we understand that it isn't a swap that can happen immediately. Being from an auction it's a good idea to get it checked out before you'd think about building it.
Digging into this we found that a 2002 Silverado 1500 with a manual trans would have come with a New Venture NV3500 5-speed. The NV4500 would have only come in 3/4 and 1-ton trucks. The NV3500 has a 300 ft./lbs. torque rating. The stock LR4 4.8 that would be in a 2002 Silverado produces 285-295 ft./lbs of torque. Folks have likely abused them with more than 300 ft.lbs. However, that isn't something we would recommend if this is your only mode of transportation. The E-bike sounds like a fun experiment but not something we'd want to be stuck with long term.
With that being said it seems you're at a crossroads. There are quite a few different avenues you could take. You could leave the truck be and just drive it. Maybe you do a mild cam swap in the 4.8 to take care of the performance itch. Look into a trans swap if you want to start making a good bit of power. Look for a different truck that already has a 5.3 or 6.0 in it with an auto trans and sell your current inventory. There are probably a bunch of other avenues but this gives you an idea. Decisions, decisions, decisions
Thanks for getting us more info on the 5.3. Since it is a bare block, we understand that it isn't a swap that can happen immediately. Being from an auction it's a good idea to get it checked out before you'd think about building it.
Digging into this we found that a 2002 Silverado 1500 with a manual trans would have come with a New Venture NV3500 5-speed. The NV4500 would have only come in 3/4 and 1-ton trucks. The NV3500 has a 300 ft./lbs. torque rating. The stock LR4 4.8 that would be in a 2002 Silverado produces 285-295 ft./lbs of torque. Folks have likely abused them with more than 300 ft.lbs. However, that isn't something we would recommend if this is your only mode of transportation. The E-bike sounds like a fun experiment but not something we'd want to be stuck with long term.
With that being said it seems you're at a crossroads. There are quite a few different avenues you could take. You could leave the truck be and just drive it. Maybe you do a mild cam swap in the 4.8 to take care of the performance itch. Look into a trans swap if you want to start making a good bit of power. Look for a different truck that already has a 5.3 or 6.0 in it with an auto trans and sell your current inventory. There are probably a bunch of other avenues but this gives you an idea. Decisions, decisions, decisions
Some of the Regency short beds also came from Regency with a centrifical supercharger installed. The NV3500 seemed to live with the supercharger. I have driven one such truck.
The early NV3500 4.8Ls had a long crank like the long crank 6.0L and I believe the later ones had the same spacer you would find with a 4L80E.
Last edited by Fast355; Mar 5, 2023 at 09:11 AM.
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