LS3 durability on a reasonable budget

[another69]

Doing an LS3/480 swap into my car and I want it to be able to take lots of abuse while living a long & happy life. Mainly street driving and track days. I'd love a high end forged bottom end and all kinds of exotic parts, but the costs add up real quick so I was thinking about what it would take to make a crate motor like this survive. Please chime in with anything that you see wrong with my "formula":

-LS3/480 crate motor (leave it under 500hp so the crank, rods, pistons should be ok)
-Upgrade pushrods and rockers for durability
-Keep rev limiter at 6500
-Run a dry sump system (looking at an Aviaid option that uses the factory pump for pressure and a 2 or 3 stage belt drive scavenge pump)

I have limited real world experience with LS motors, but from what I have read, heard, and seen online it seems that windage and loss of oil pressure from uncovered pickups are real concerns when these motors are pushed hard. I realize that the dry sump kit is a bit of an oddball on a mainly stock LS3...

[Schwartz Performance]

Add ARP rod bolts to your list.

Rockers are fine, but upgrade the bearings.
May want to upgrade valve springs, or just make it a maintenance item after a year of racing.

Dry sump is nice, but pretty expensive.. Might just want to do an accusump and an Improved Racing baffle for whatever pan fits your application.

-Dale

[raustinss]

Yep Id agree, ditch the dry sump idea. Go wet sump, a cam, better bearings and arp studs . You'll have a great motor with decent power numbers

[71RS/SS396]

Doing an LS3/480 swap into my car and I want it to be able to take lots of abuse while living a long & happy life. Mainly street driving and track days. I'd love a high end forged bottom end and all kinds of exotic parts, but the costs add up real quick so I was thinking about what it would take to make a crate motor like this survive. Please chime in with anything that you see wrong with my "formula":

-LS3/480 crate motor (leave it under 500hp so the crank, rods, pistons should be ok)
-Upgrade pushrods and rockers for durability
-Keep rev limiter at 6500
-Run a dry sump system (looking at an Aviaid option that uses the factory pump for pressure and a 2 or 3 stage belt drive scavenge pump)

I have limited real world experience with LS motors, but from what I have read, heard, and seen online it seems that windage and loss of oil pressure from uncovered pickups are real concerns when these motors are pushed hard. I realize that the dry sump kit is a bit of an oddball on a mainly stock LS3...

You have a good realistic plan for the most part. If you're going to make the leap to an external pump I would use it for the pressure side as well, the stock pumps start going into duress above 6,300 rpm and aerate the oil. Make sure you have a tank that has enough capacity. Look at cams and valve springs that are designed for endurance use, they will have softer ramp angles and will be easier on the valvtrain parts. You'll likely give up some peak power but the durability will be better and you'll have less valvetrain maintenance. I don't personally like the aftermarket needle bearing trunion upgrades and prefer the bushing style that Straub Technologies and few others sell, if you're going to change the pushrods use ones that are restricted.

[another69]

I didn't consider the rod bolts but it is a good idea. Dumb question- Can the rod bolts just be replaced and torqued to spec or does the bearing clearance need to be checked? The mains and crank look to be pretty beefy on these motors, so my plan was to leave those untouched. Do they need help too? I've thought of upgrading the valvesprings from the beehive to a dual spring. Not sure about the pros and cons though. Maybe a yearly swap out like you suggest would be a good call.

I want this motor to be fairly low maintenance, so that's why I was looking into the external scavenge only pump with OEM pressure pump. Also it seems like (I may be wrong here) all the underhood oil lines would be low pressure, so less chance of a leak. Plus if the belt breaks the motor would start to overfill with oil, but it would't lose oil to the bearings right away like on a complete external pump. Again, I really don't have a bunch of hands on knowledge with the dry sumps either, and appreciate your input.

Not sure about the cam ramp angles but my plan was to use the factory "hot cam" that comes with the LS3/480. I know the lift is .525ish, so it should be easier on the valvetrain, right? I agree about the bushing style rockers. I'm surprised the aftermarket doesn't offer more rockers for these engines. Pushrods I was looking at were just upgraded 1 piece for durability. When do you need oil restricted pushrods?

[raustinss]

I would tend to think that when you have dry sump you will get more maintenance... possibly with oil leaks and as you said a belt breaking

[coby74]

If you keep your cam check the cam sprocket bolts. My ls3 525 lasted 113 miles. The dealer did not want to touch the engine because it was in a older truck so I took the front cover off and seen the cam sprocket about to fall off and the camshaft walked and completely ruined the engine. After taking the pan off the oil pickup tube bolt was sitting on the bottom of the pan. It probably was assembled on Friday afternoon. Gm finally gave me another engine and the first thing I did was upgrade the cam sprocket bolts and put Loctite on. Its been 2 1/2 years and this one is still going strong.

[71RS/SS396]

I would tend to think that when you have dry sump you will get more maintenance... possibly with oil leaks and as you said a belt breaking

There's no added maintenance with a dry sump and if you use quality fittings they don't leak. I've had the same belt on my pump for 2 years of abuse with no issues, I keep a spare zip tied in the trunk in the event I break one. The oil changes are slightly more involved but you also get a more complete oil change since you remove the belt and run the pump with a drill to pump any remaining oil in the system back to the tank.

[71RS/SS396]

I didn't consider the rod bolts but it is a good idea. Dumb question- Can the rod bolts just be replaced and torqued to spec or does the bearing clearance need to be checked? The mains and crank look to be pretty beefy on these motors, so my plan was to leave those untouched. Do they need help too? I've thought of upgrading the valvesprings from the beehive to a dual spring. Not sure about the pros and cons though. Maybe a yearly swap out like you suggest would be a good call.

I want this motor to be fairly low maintenance, so that's why I was looking into the external scavenge only pump with OEM pressure pump. Also it seems like (I may be wrong here) all the underhood oil lines would be low pressure, so less chance of a leak. Plus if the belt breaks the motor would start to overfill with oil, but it would't lose oil to the bearings right away like on a complete external pump. Again, I really don't have a bunch of hands on knowledge with the dry sumps either, and appreciate your input.

Not sure about the cam ramp angles but my plan was to use the factory "hot cam" that comes with the LS3/480. I know the lift is .525ish, so it should be easier on the valvetrain, right? I agree about the bushing style rockers. I'm surprised the aftermarket doesn't offer more rockers for these engines. Pushrods I was looking at were just upgraded 1 piece for durability. When do you need oil restricted pushrods?
The hot cam will be easy on the valvetrain with its low lift and soft ramp angles. I wouldn't worry about any of the bolts in the bottom end since you're going to limit the rpm to 6,500. The only reason a belt should break is from debris getting in it, something failing in the pump or engine causing it to lock up, or from it simply being too old. I've used the same belt on my 5 stage for 2 years with no issue but I do have a warning light should I lose pressure. There's no doubt the plumbing packaging is more involved with an external pump but if you use high quality fittings and lines you won't have any leaks, my car is a maze of plumbing with the 5 stage, remote oil filter, cooler, and oil cooler thermostat but I have zero leaks. You're probably going to be at $4-$5K by the time it's all said and done with the pan, pump, plumbing, and tank.

[another69]

Yeah, I was figuring about $4K or so but it should be money well spent if it eliminates the windage and the possibility of uncovering the pickup. I guess I could just fab up a simple belt cover to protect the pump. Is my thinking on the right track with using the external pump for scavenge only? It should minimize the lines and complexity and still do what it needs to do at the RPMs I'll be reaching.

I guess my main goal is to not hurt the motor at my power level while on the track without having to "baby" it. My last motor (SBC) has bearing damage, and it's a good chance that it was because either it lost oil pressure for a moment (baffled pan with windage tray), or the main caps moved. Trying to avoid that this time around.

[71RS/SS396]

Yeah, I was figuring about $4K or so but it should be money well spent if it eliminates the windage and the possibility of uncovering the pickup. I guess I could just fab up a simple belt cover to protect the pump. Is my thinking on the right track with using the external pump for scavenge only? It should minimize the lines and complexity and still do what it needs to do at the RPMs I'll be reaching.

I guess my main goal is to not hurt the motor at my power level while on the track without having to "baby" it. My last motor (SBC) has bearing damage, and it's a good chance that it was because either it lost oil pressure for a moment (baffled pan with windage tray), or the main caps moved. Trying to avoid that this time around.

My preference would still be to use the external pump for pressure as well, the stock pump will cavitate above 6,200-6,300 rpm which will aerate the oil. Aerated oil does not lubricate as well and can slowly damage the bearings, with that said the scavenge only pump is still better than a stock wet sump.

[another69]

Good point about aerating the oil, but my time above 6000 should be minimal. Did you buy a dry sump kit or piece it together?

You mentioned earlier in the thread about restrictor pushrods. I'm familiar with oil restrictors on SBC motors, especially when going from a hydro cam to a solid, but why would you want to restrict it on an LS? to keep too much oil out of the top of the head? I know that some oil is needed to keep the springs cool. I'm asking because it's another area on these LS motors that I am unfamiliar with.

[71RS/SS396]

Good point about aerating the oil, but my time above 6000 should be minimal. Did you buy a dry sump kit or piece it together?

You mentioned earlier in the thread about restrictor pushrods. I'm familiar with oil restrictors on SBC motors, especially when going from a hydro cam to a solid, but why would you want to restrict it on an LS? to keep too much oil out of the top of the head? I know that some oil is needed to keep the springs cool. I'm asking because it's another area on these LS motors that I am unfamiliar with.

I bought a Dailey 3 stage (billet pan and pump) intially, but the pump couldn't keep the crankcase in vacuum at high rpm, so I had them build me a 5 stage pump to work with my set-up. We made our own tank, and pieced the rest of the components together that I wanted in the system. My advice would be to buy the pump and pan and piece the rest of it together, these "kits" rarely work in these old cars due to space constraints, you'll likely have to modify the tank or the car to get it in. Roush-Yates sells a lot of used tanks at substantial discounts so I would look there for a tank you can modify.

The restricted pushrods keep excessive oil out of the heads, but if you don't plan on sustained high rpm you probably don't need them.