QwkTrip

iTrader: (22)

Converting an LS7 from dry sump to wet sump is fairly easy. It's basically a process of changing things from LS7 spec parts to LS2 / LS3 spec parts.

The LS7 oil pump is deeper front-to-back than other LS oil pumps, and that extra girth pushes everything else in the stack-up further away from the engine than normal. The crankshaft sprocket is deeper, the front cover is deeper, the hub of the harmonic damper is set out further, the crankshaft bolt is longer, and even the crankshaft itself is longer. Converting to wet sump results in a shorter oil pump that moves the stack-up of parts closer to the engine like an LS2 / LS3. Pretty much all the parts unique to the LS7 are going to be set aside and replaced with parts from LS2 / LS3.

Procedure

Remove the LS7 damper and front cover and set aside. Neither of these parts will be re-used with the wet sump system.




Remove the LS7 oil pump. Also remove the LS7 oil pan and windage tray.




Remove the LS7 crankshaft sprocket and discard. The correct tools are Kent Moore J-41816-2, J-41558, and J-8433-1, but those things are pretty expensive. Hopefully you have better tools than me though because my puller jaws kept slipping off which made it very difficult to get the sprocket off the crank. I cut the threads off the stock damper bolt (leaving the smooth shank) and slipped it in the end of the crank to give something for the puller to load against.




Install a new LS2/LS3 crank sprocket. I used the old LS7 sprocket as a spacer over the crank snout to help drive the new sprocket in place.




Install the timing chain and new oil pump. Pump shown on this LS7 is a Melling high pressure, standard flow. LS9 requires a high volume pump due to extra oiling demand of piston squirters.




Install a new LS2/3 front cover. SacCity Corvette sells a tool to help align the front cover lip seal concentric to the crankshaft snout.




A new harmonic damper will be needed because the hub position of the LS7 damper is incorrect for the new parts stack-up. There are two ways to go about this. A longer LS7 damper bolt is required either way.

• LS1,2,3 style damper of your choice with a Scoggin Dickey hub spacer. The spacer takes up the extra length of the LS7 crank so the damper bolt has something to tighten against. The Scoggin Dicky hub spacer is too large diameter though to fit inside ATI dampers. In that case you'll need to either turn down the outer diameter of the spacer, or make your own spacer.
  
• Custom damper from ATI with longer LS7 style hub. No spacer is needed. This is about a $200 upcharge.

Pictured on right: Scoggin Dickey crank spacer
Pictured on left: Custom made aluminum spacer for ATI damper




LS7 does not have an engine dipstick so a hole will need to be drilled in the engine block. AFX sells a drill guide that bolts to the engine block. Use a larger drill bit to create a nice lead-in chamfer.




Install whichever oil pan and windage tray you choose. The engine pictured below is fitted with an Improved Racing crank scraper EGM-742, and Improved Racing windage tray for Holley 302-1 oil pan.

obeymybird

iTrader: (4)

Just want to add the other option and the way I did mine.

The only change I did was to have the longer ls7 crank snout machined down to normal ls wet sump length everything else will fall in line with QwkTrip’s perfect write up.

QwkTrip

iTrader: (22)

Thanks!