allblowdup

What parameter should a guy be looking at? Basically I will have a 2.5" stroke turning 7500 rpm all day. Lots of oil cooling and around 4 hp per cubic inch on E85.

Patron

RPM and the wet sump oiling system not being enough. Guy's using wet sump systems tend to run a Vacuum pump and maybe a accusump also.

Again quick Google search shows:
https://en.wikipedia.org/wiki/Dry_sump
https://www.dragzine.com/news/canton...-does-it-work/

allblowdup

I have used accusumps in the past and def food for thought but what I have found in the past is that the longer the stroke the lower rpm one starts having oiling issues because of windage. In a 4.125 stroke,wetsump seems to be fine up to at least 6500 rpm.piston speed of that is around 5500 but a 2.5 stroke at 7600 is only 3100. If windage is so much less for a 2.5 inch stroke at that being the main factor maybe a dry sump is not needed.

Patron

With only 7500 for Rpm which isn't asking much I'd think a good oil pump *vacuum pump kit (GZ),*crank scraper, & *accusumps would be more than enough(I also use this combination for future stuff with 8300 rpm in mind for short periods). Once you get over 8k+ for extended periods of time is when a dry sump is or should be considered, is it better yes, is it needed probably not @ 7500.

I like to ask what size rod bearings does it use Honda rod 1.88 or normal 2.10 - 2.0 bearings.

allblowdup

Haven't decide on the rod bearing sizes yet. I was thinking of the honda journal though. One of my biggest issue is going to be the real long rod that I will need and the weight that comes with that not to mention the piston will probably end up kinda tall also.

8.Lug

showdog75

iTrader: (8)

shhhhh.... grown up's are talking. I'm pretty sure they already know what you mentioned.

pdxmotorhead

I've watched head to head tests on the same engine with dry sump and wet sump 3 different motors,
Once you over 500hp or so on a small block the dry sump is good for 5 to 10 % more HP..
And this was at a truly NON hack engine shop.

They were sorting out power for a salt flat car.. They went dry sump..

There advantage is the dry sump can hold 10 quarts of oil in a small space and keep it cool, it also allows for
plumbed in oil squirters under the pistons.. makes oil changes easy as hell too.. LOL

QwkTrip

iTrader: (23)

So that's about 1000 Hp out of a 4L engine?
Turbocharged?

allblowdup

Yup pretty much. The application does have alot of different forces including lateral G force of spikes up to 2.2 G, not much slowing down unless you crash as we have no brakes.

QwkTrip

iTrader: (23)

Is this a boat? I think people were answering too soon before they knew what was going on.

allblowdup

Yes it is a river racing marathon jet boat.

00pooterSS

iTrader: (40)

Pics?
Motor specs?

Sounds like a cool build

As for the original question the obvious answer is if you are having oiling issues due to g forces.

But it does a lot more, helps cool the engine, keeps consistent pressures, reduces pumping and windage losses and temps. So IMO if you have the means and money to run a dry sump, run a dry sump. It just makes everything better. And mo powa too.

G Atsma

I agree! Just the thought of it never starving for cool, clean oil is reason enough to go dry sump. I'm surprised wet sumps do as well as they do considering it's basically sucking out of a small bathtub with all the g-forces happening to it...

00pooterSS

iTrader: (40)

I watched an engine masters episode where they tested oil levels in the pan the other night. Was super interesting to see what oil level alone did to oil pressure and power. Made me like dry sump that much more.

I recommend checking out the episode.

pdxmotorhead

So in the thought process, here,, whats the downside of the dry-sump? (Other than cost.,... )
I've had friends do pretty well picking up used pumps and mounting at Oval track swap meets
then sending the pumps and wearable parts in to get them rebuilt. Works out to about 1/2 the price of new..

If I had a high power expensive boat,, picking up a dry sump doesn't seem like a big deal of cost..
Also,, especially in a boat the dry sump pan will give you more room under the motor making service
easier too. (I always hated oil changes on my inboard .. )

If I recall,,, and man this is going back to some OOOOLD brain cells, if you have a velvet drive style power
unit you can reduce the drive shaft angle to the velvet a lot with a dry sump, making the power transfer even smoother..

allblowdup

I think I have pretty much decided on going the dry sump route. The only reason for thinking about leaving it wet sump was the simplicity, cost, and reliability. I don't think any of those are enough to make a guy take a chance on the wet sump. The reliability is only with the belt drive in case something got caught in it. We have hit a few birds and they sometimes end up in the engine compartment. This is our race trailer vid from 2011

LSX67RS/SS

just my .02 i'm running a dailey dry sump love the system but just as you quoted above....something gets in the belt drive it becomes a disaster...I lost my serpentine belt last track day and it wound up in the dry sump belt.....immediate oil pressure lost including a bent shaft on the dry sump pump. Still going to use it but looking to rectify the serpentine belt issue....

00pooterSS

iTrader: (40)

Man that looks like fun. What motor are you guys running?

allblowdup

I have ran BBC 469 ci, 366 SBC, crate CT525, and a LSX454 at around 750 hp. Can't afford the turbine class however.