EL CAMINO Scored a 6.0 today
- Thread starter Gremlinsteve
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Rods and pistons? Really?! Dafuq.
Stock LS2 (6.0) with a LS9 cam and a used Procharger took my 5300lbs TBSS into the 11s. But, you do you.
I am out.
motor has 300k on it
I’m just figuring it might need a freshening
If I’m there I might as well add the gen 4 rods correct?
I’m just figuring it might need a freshening
If I’m there I might as well add the gen 4 rods correct?
And leave the rotating assembly unbalanced? If it's NA either send it as is or hone/rering, polish crank and send it.
No need for 500 crank HP.
NA a Walbro 255 or 450 is plenty of pump. In tank a single 450 is plenty.
And unless you intend to putt around only, you'll want a converter. You can always change it later too.
NA a Walbro 255 or 450 is plenty of pump. In tank a single 450 is plenty.
And unless you intend to putt around only, you'll want a converter. You can always change it later too.
Honestly a 300k LS can be the same as a 150k LS in terms of wear depending on how it was used and taken care of. Mileage is a very soft indicator of the true condition on modern EFI stuff. LS stuff doesn't 'ring ridge' wear like a 70's SBC because 1. the carburetor isn't washing the cylinder walls down on startup 2. materials are a lot better 3. oil tech is better
If the valve covers and rocker areas aren't sludged up the best scenario is likely to leave it alone. The likelihood it will get worse in rebuild than better is like 50%.
If you pull the cam out and the cam bearings are really bad or fall out when you pull he cam it's obviously a good idea to replace them
The O ring on the oil pan pickup tube should be replaced as it dries/cracks over time and you can suck air
The little seal in the cam retainer plate should be replaced as its a common leak path.
But as far as rings or main/rod bearings if it's ran well for 300k it's likely going to run well for another 200k. GM had thousands of engineers designing the best design, mfg, and testing processes they could, a guy in a machine shop isn't going to improve that.
I'd take a dirty exterior LS wth 300k over a 'cherry' 120k LS that is clean. As long as the inside looks clean it's likely fine. Honestly clean LS's scare me because that means someone hit it with a pressure washer and it likely ingested water and it's been rusting a cylinder.
If the valve covers and rocker areas aren't sludged up the best scenario is likely to leave it alone. The likelihood it will get worse in rebuild than better is like 50%.
If you pull the cam out and the cam bearings are really bad or fall out when you pull he cam it's obviously a good idea to replace them
The O ring on the oil pan pickup tube should be replaced as it dries/cracks over time and you can suck air
The little seal in the cam retainer plate should be replaced as its a common leak path.
But as far as rings or main/rod bearings if it's ran well for 300k it's likely going to run well for another 200k. GM had thousands of engineers designing the best design, mfg, and testing processes they could, a guy in a machine shop isn't going to improve that.
I'd take a dirty exterior LS wth 300k over a 'cherry' 120k LS that is clean. As long as the inside looks clean it's likely fine. Honestly clean LS's scare me because that means someone hit it with a pressure washer and it likely ingested water and it's been rusting a cylinder.
If you're buying an LS9 cam for much more than $100-125, then spring for a new one. The extra $100-125 isn't a deal breaker. And the LS9 cam is nothing like the Elgin stage 1 or stage 2. People used to use the LS9 cams a lot before the cam selection is what it is now.
I have a list of things I do when swapping the cam - new head gaskets, new oil pump, new lifters. The seals that 81cutlass mentioned are a must. You can spring for a new gasket kit as well - ebay or Amazon special for $50 or so. But if the old gaskets aren't leaking and come off in one piece, then they won't leak when you put them back on. If you price these out individually you'll spend about 5 times what you need to. Be sure to inspect the rocker trunnions and pads for excessive wear, and the pushrods for galling on the ends and length.
Regarding lifters and oil pump, I use stock replacements, nothing special - I get Sealed Power lifters from Advance auto using a coupon code buying two lifters at a time - last time round I payed $14.50 for 2. The oil pump is a Melling M295. For head gaskets, I was using the BTR house brand, but since I started making lots of boost I use LS9 (more layers). The LS9's aren't the greatest for a 5.3, but the minor amount of inefficiency created with the loss of compression due to the larger bore and added thickness isn't an issue for me. I shim the stock oil pump spring with .100"-.120" of washers to raise the stock Gen 3 oil pump pressure to 40-50psi at idle.
If you want a true idea of the condition of your motor, then cut open the oil filter, drop the pan and inspect and the degree of buildup under the valve covers. I prefer a leak down to compression test.
My current motor was a $250 take out core and I put less than $650 into it. But I also changed the springs to Pac 1218's. It's stuck together for a bit at 20+psi and I spin it to 7500 regularly.
But, if you're an OCD type like Texas82GP then buy new everything (haha Jared). But for a 300K motor I couldn't bring myself to have $2K worth of new parts without a full rebuild.
Best of luck - Jim
I have a list of things I do when swapping the cam - new head gaskets, new oil pump, new lifters. The seals that 81cutlass mentioned are a must. You can spring for a new gasket kit as well - ebay or Amazon special for $50 or so. But if the old gaskets aren't leaking and come off in one piece, then they won't leak when you put them back on. If you price these out individually you'll spend about 5 times what you need to. Be sure to inspect the rocker trunnions and pads for excessive wear, and the pushrods for galling on the ends and length.
Regarding lifters and oil pump, I use stock replacements, nothing special - I get Sealed Power lifters from Advance auto using a coupon code buying two lifters at a time - last time round I payed $14.50 for 2. The oil pump is a Melling M295. For head gaskets, I was using the BTR house brand, but since I started making lots of boost I use LS9 (more layers). The LS9's aren't the greatest for a 5.3, but the minor amount of inefficiency created with the loss of compression due to the larger bore and added thickness isn't an issue for me. I shim the stock oil pump spring with .100"-.120" of washers to raise the stock Gen 3 oil pump pressure to 40-50psi at idle.
If you want a true idea of the condition of your motor, then cut open the oil filter, drop the pan and inspect and the degree of buildup under the valve covers. I prefer a leak down to compression test.
My current motor was a $250 take out core and I put less than $650 into it. But I also changed the springs to Pac 1218's. It's stuck together for a bit at 20+psi and I spin it to 7500 regularly.
But, if you're an OCD type like Texas82GP then buy new everything (haha Jared). But for a 300K motor I couldn't bring myself to have $2K worth of new parts without a full rebuild.
Best of luck - Jim
And no matter what you do, please buy new lifter trays. You might regret it if you don't.
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