385ci SBC Marine Oil

[Ryan02SS]

I built a new 385ci SBC for my Challenger over the winter. I'm currently breaking it in with Castrol GTX 10W-30 for a few hours. I'm looking for a good oil I can find locally that will be the best for this motor. I'm debating between Mobil Delvac 1300S 15W-40 or Mobil 1 10W-30HM mixed with M1 15W-50 Syn to make a nice 40W with a strong additive package. I've used the 1300S in my last two motors with great results. Both were 375-425hp SBC's. Upon teardown the internals looked really good. Very visible crosshatching, minor skirt wear, no bore polishing and great compression and leakdown numbers. The 360ci had 360hrs and the 355 had 136 hrs.

I change the oil religiously @ 25-30hr intervals. I mainly cruise 2500-3500rpms most of the time but race alot also with extended WOT runs at 5700-6000rpms. I have a large oil cooler and temps never rise much above 240*. Total oil capacity is a little under 8qts.

Videos of my Challenger
http://www.youtube.com/watch?v=ORkMT3JMWu8

http://www.youtube.com/watch?v=0HW3bFdTj88

http://www.youtube.com/watch?v=vuL_dEX0SoM


Engine Specs....
Ring Gap Top .022", Bottom .020" Mains .0015 Rod .0015
010 4 bolt SBC, bored .040", 0 decked, line honed,
ESP 4340 3.750 crank, ESP 6" 7/16" H beams, Mahle forged FT's 5cc, C77H bearings, Hines Balanced
Melling Racing #10555 oil pump, Hamburgers 7qt marine pan, full length windage tray.

FluiDamper harmonic balancer,
AFR 190cc heads, 73cc, further ported by Carl McQuillen Racing Engines, Isky 6105 dual valvesprings,
Marine Kinetics "RMbuilder" custom Hyd Roller 234/240 .580/.568 112+4
Morel Retrofit Hyd Roller lifters
Smith Bros .083" wall pushrods
Edelbrock RPM Air Gap port matched to AFR port
Holley HP 750 DP
Lunati Voodoo Widebody 1.5 roller rockers
GLM aluminum manifolds
FastGlass Stainless 22" long dry risers
Full MSD ignition setup, coil, wires, dist, 6AL,
10.07-1 SCR

 

[Steve S]

Seems like you have the engine work down to a science .I don't think you can beat the heavy duty motor oils especially since the oil temps are under control.

 

[Brett Miller]

If it was mine, it would be running Amsoil.

 

[Steve S]

Originally Posted By: Brett Miller
If it was mine, it would be running Amsoil.
Why? I have run HDEOS in my bigblock Chevys With great results upon teardown .These were up to 7,500 rpm engines.Why spend more for oil that is drained often? For the price of a uoa you can have fresh oil .With an engine tuned for max power there will be some fuel dilution.

 

[Lost1]

Delvac, Rotella, Delo, etc. would all be good choices. I use Rotella or Delo in my little 190 hp 4.3 Mercruiser, and have always had great results. Straight M1 15W-50 is also an excellent oil- especially for a hi-po motor like yours.

Sounds like a cherry boat. Is it a jet drive or a prop? I'll bet a B2 would make that baby SCREEEEEAAMMM!!!\

 

[Ryan02SS]

I have two Alpha 1 outdrives for the boat. It's nice having a spare when you are overpowering these drives. Both have HD gearsets, Hydromotive nosecones and drive showers with Syn Merc gear oil. I am running a labbed 23P 14.5" dia Merc Racing 3 blade cleaver prop. It might be a little too much pitch for the new motor so I might drop back to a 24-25P.

Thanks for the ideas guys.

 

[RTexasF]

Nice rig and a classic. Too much pitch or too little? Is it over revving at top end? I was curious how that alpha drive held up, smart move to have a spare, drive shower(s) and nose cone. Stock water pick ups or are they in the nose cone? The second video doesn't load for me by the way.

 

[Volvohead]

Originally Posted By: Ryan02SS
I have two Alpha 1 outdrives for the boat. It's nice having a spare when you are overpowering these drives.


That's a lot of engine to be running through an Alpha.

I'd be more concerned about the outdrive lube than the engine oil.

 

[Ryan02SS]

Originally Posted By: RTexasF
Nice rig and a classic. Too much pitch or too little? Is it over revving at top end? I was curious how that alpha drive held up, smart move to have a spare, drive shower(s) and nose cone. Stock water pick ups or are they in the nose cone? The second video doesn't load for me by the way.


Thanks! I've only seen one other Challenger before so they are somewhat of a rare boat. I've yet to take the boat full WOT as I am breaking in the outdive I rebuilt over the winter. Last years 355 WOT @ 5500-5700rpms depending on weight in the boat. With 30 more cubes, larger cam, better exhaust and more compression i'm thinking the 23p will rev past the 5800-6000rpm peak hp of the combo. I have the stock water pickups. The Alpha's have been fine for me. I've yet to break one and I run it pretty hard. My boat is also very light 2600lbs loaded which helps alot. I did tear up the original R drive that came on the boat. I sprayed a 100shot and took the teeth right off the F gear.