Simmo

Im assembling a 383 and a 540 for street use. Im interested in opinions on value of crank scrapers in street applications. The smallblock is a numbers matching deal with all the factory head, exhaust, sump limitations so Im looking for any little thing that can help.

Do you use one on each side, how many hours are needed to fit them. do the cause oil leaks.

cardo0

Yea i bought one. After i looked it over and realized all the work to fit it up i left it alone. Somehow u have to fit it tight enough to the to wipe the oil - very tight clearance - but not rub the at any rpm. Also have to get the pan to seal as that scraper is held in by the pan bolts.

Yes they install on one side only. And they're worth only a few ponies at high rpm. I just see more than can go wrong using one than the gain i would get from it. But hey if you can do it let us know what u think.

Good luck,
cardo0

gkull

350 - L82 motors had a kind of a crank pan stripper attached to the longer main cap bolts. the diamond stripper was the aftermarket choice.

Adjustable right hand side crank strippers come with aftermarket big baffled oil pans. you have to fit them for every different crank type.

My 383 has oil restrictors to the top end, cam valley breathers, and crank strippers on an 8 quart road racing pan.

Every minor thing helps, but I would put the most money into good cold air intakes, manifolds and free flowing exhaust

Matt Gruber

took 7 hrs to fit mine. .015", 10 years ago.
ever since, i keep only 3 qts in the pan.
the less oil in the motor, the more HP.

FB007

Then try no oil. Should see a large gain.

Matt Gruber

That experiment i leave to YOU!
Myself, i use a red 50psi warning light, and it never turns on. Have PSI, will travel.(old TV show: Have Gun, Will Travel)

fauxrs

The last three motors I've built, I've fitted crank scrapers. They can indeed be tedious, though 7 hours is a lot more than I ever spent fitting one.

They are so inexpensive, and I enjoy my building time that I've never felt the need to not install one.



What I do is clearance the crank throws first - without the piston/rod assemblies in. then after I fit those I clearance them.

gkull

The problem with 3 quarts is how fast the oil temp could rise when under load. I use 9 quarts and a 3 quart Accusump for 12 quarts. Before accusump I would loose oil pressure in any longer turn on the road racing track or even with my street tires on a big circle freeway on or off ramp when pushing up the speed.

This kind takes more hours to fit and I have it along with the morroso 8 qt RR pan.

http://www.jegs.com/p/Moroso/Moroso-...45546/10002/-1


The diamond stripper.

http://www.jegs.com/p/Milodon/Milodo...45511/10002/-1

midyearvette

ok ok matt..you got me here.....i have seen guys in the old days pull the drain plug to make a run at the record and then go through the mill for the next week but i dont get how 3 qts. vs 5 or what ever has anything to do with it......enlighten me obie won.....

yellow 72

Someone...anyone... post any benefits or horsepower gain of a crank scraper on a street motor

Matt Gruber

i've seen enough articles & dyno tests to run the minimum GM spec. i have 4qt pans, ADD is at 3 qts. i only add 4 ounces.
pull drain plug
how does that help?
.
gkull
your in a whole 'nother world. road racing etc. If u say the oil gets too hot, i believe it.
BUT, one of the articles showed too much oil GETS HOTTER. So more oil can make it worse, if it wraps around the crank, and that heats it up. U could try a tight scraper and lots less oil if u want. I'm no expert on this, but i was convinced enough to try it. Before with a full pan, i'd lose psi around a FAST corner. Now, 1qt down w/scraper it maintains FULL psi. I'm in a grocery store parking lot, nothing like the racing u are doing. 10 yrs ago i was reading Circle Track Mag, that's probably what motivated me

gkull

Both of my motors have the latest and greatest scrapers, baffels, and deep side pans. My Moroso deep pan is like 8.5 inches. It uses your same 3 qt idea. Even with 9 quarts it read over a quart low with my stock dip stick. So I had to make a dip stick and cut notches as to where full is. I use a big one qt. filter

Matt Gruber

Right! The article said u can run as much oil as u want, just KEEP IT AWAY FROM THE CRANK.

fauxrs

2-3% hp gain seems to be the going rule of thumb for a scraper, obviously this is at high rpms, gains at low rpms would likely be negligable to non-existant.

I read an article once attributing a 15 hp gain for windage tray/scraper combo on a dyno for a small block. If memory serves the motor made on the order of 400hp before the addition.

anectdotal of course I've never dynoed such a setup.

BB72

Unless you've already eeked every little bit of HP out of the motor doing all the much simpler and less tedious things this would be a waste of time. Cooler oil, cold air intake, oil drain back...etc would be much easier. Why towel dry yourself in the running shower....

FB007

chevymans 77

Jim (427Hotrod) posted some interesting info on a Milodon pan, I'm looking at one for mine.

First Post by Jim;

"The Milodon #31188 *stepped drag race pan* is one of the best out there. It will fit our chassis without stock P/S. But it will clear a Steeroids setup. It's a little low, about dead even with the bottom of a scattershield, but well above most big block headers. I've run one for years and we've got them on several 540-632" C-3's and they all do well."

Second Post by Jim;

"That pan usually is worth 10-15 against most of them, but with the new Milodon changes to internal baffles they swear it was 9HP better than the version on my car. Do a search on Car Craft or Hot Rod. One of them did a back to back test with it on a mini test a while back and it did well. The higher you spin it or the longer the stroke...the better it will do."

Neal

fauxrs

Why would it be a waste of time, not doing all those things you mention doesnt de-legitimize the use of a scraper or windage tray. A crank scraper costs all of $15 and shouldnt take more than a couple hours to install. Install is simple, just time consuming.

Even if it were only good for a 1% increase in hp (say 3 hp in a 300 hp motor) name another mod good for 1 hp for every $5.

BB72

I'm not saying don't do it, I'm saying that there are other mods worth more HP than a crank scraper that I myself would be putting my time into. We all know it works to some degree. If you're building a circle track car that will constantly see the drag of that extra oil then go for it. On a street car you probably wouldn't even notice it. Just my two cents.

The OP is looking for opinions isn't he?

toddalin

There are lots of changes that we make to our cars that don't result in a definite SOP feel, but we do them anyway just knowing that the technology theoretically should make some difference for the better. How many of those "air foils" do you think they sold for C4 plenum intake tracts? I have one in my '91 and never noticed any SOP difference.

I'm as guilty as anyone (probably more than most) of these small, what most people consider as worthless changes, and could easily point to half a dozen on my engine, but my dyno sheets back up these mods and there are few engines on this forum that are as basic and mild as mine but yield the RWHP that I get. Cumulatively, they all add up.