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-   -   Crank Scraper? (https://forums.maxperformanceinc.com/forums/showthread.php?t=777196)

1969GTO 07-18-2015 04:48 PM

Crank Scraper?
 
Is it worth it on a street/strip car? [crank scraper]
I already have a baffled stock pan and windage tray.

70 bird 07-18-2015 05:22 PM

In a street car a little windage might be good for the cam lobes.

1969GTO 07-18-2015 05:38 PM

It's a roller [cam], if that matters.

leeklm 07-18-2015 10:43 PM

I have heard builders claim 10hp on the dyno with a scraper, but not sure if that was with or w/o a windage tray, etc. Since they are like $12, I installed one just in case :)

1969GTO 07-18-2015 11:47 PM

Scraper
 
Quote:

Originally Posted by leeklm (Post 5435031)
I have heard builders claim 10hp on the dyno with a scraper, but not sure if that was with or w/o a windage tray, etc. Since they are like $12, I installed one just in case :)

You found a crank scraper for $ 12.00?
How was it sealing the pan since 1 side ends up being higher with the scraper installed?

leeklm 07-19-2015 12:08 AM

Maybe that was the price I told my wife??

I have installed two of them with no leaks. The scraper goes around the ends of the block rail up to where the rear pan seal-end connects with the block. I used Ultra RTV between the block and scraper, and then used some RTV where the end seals on the pan contact the scraper. All is good.

Hooter 07-19-2015 12:38 AM

I've never ran a scraper or windage tray in any of my motors. But, they're only in the 800 hp range.

Elarson 07-19-2015 08:09 AM

The cloud of windage takes some horsepower to keep it whirling around in your crankcase. Think of the crankshaft as a big inefficient pump. But the windage cloud carries additional oil that will get deposited on your pistons, cylinder walls, cam and lifters.

So the decision comes down to gaining a few extra horsepower or making life a little easier on your moving parts.

My own opinion:

street car or bracket car...let the extra oil help the life of your parts
heads-up NA car....let the crank scraper release some HP and accept that parts life might be reduced
power-adder car....let the extra oil help the life of your parts

The windage tray serves a different function. It is to keep the oil from being directly flung into the pan, where it would tend to aerate the oil in the sump. The factory windage tray sends the oil to the side of the crankcase where it will run down into the sump. An aftermarket windage screen breaks up and slows down the blast of oil coming down off the crank.


Eric

1969GTO 07-19-2015 10:30 AM

anyone running a crank scraper with the 1 piece pan gasket?

leeklm 07-19-2015 10:39 AM

Quote:

Originally Posted by 1969GTO (Post 5435159)
anyone running a crank scraper with the 1 piece pan gasket?

I first assembled my engine with the one piece gasket and scraper. Worked fine for the 5 minutes of run time it had. I had to pull the pan (long story) damaged the gasket, and ended up picking up a standard fel pro gasket at the parts store.

1969GTO 07-19-2015 12:56 PM

800hp
 
Quote:

Originally Posted by Hooter (Post 5435071)
I've never ran a scraper or windage tray in any of my motors. But, they're only in the 800 hp range.

WOW, just imagine if you had a crank scraper :eek: :doh::car::drive::clap3::humble:

vidguy 07-23-2015 06:57 AM

I am using a scraper in my daily driver 455 I built with the one piece oil pan gasket. No issues in 4 or 5 years about 17000 miles.

BADDTA 07-23-2015 04:19 PM

Using a scraper in my sons car. Ultra grey silicone for gasket. Zero leaks and easy to clean.

Brian

1969GTO 07-23-2015 09:30 PM

gasket
 
Quote:

Originally Posted by vidguy (Post 5437187)
I am using a scraper in my daily driver 455 I built with the one piece oil pan gasket. No issues in 4 or 5 years about 17000 miles.


did you modify the gasket in any way?

Half-Inch Stud 07-23-2015 10:03 PM

Put a Spotts Crank Scraper in my Street/Strip 455 68 GTO, with Factory lobotomy pan.

Seems to have improved oil Pressure gauge stability.

Don 79 TA 07-24-2015 08:08 AM

would using a vacuum pump negate the need of using the crank scrapper?
i have seen conflicting info on this

1969GTO 07-24-2015 10:00 AM

Good question, because some people are using the vac pump to cure oil leaks on the engine, will the the vac pump bother a scrapper/windage tray?

leeklm 07-24-2015 10:07 AM

By no means an expert here, but I cant imagine how a pump would have a significant impact on using a scraper. The scrapers job is to "scrape" oil that is being picked up and slung off the crank and rod ends. The slinging of this oil is being stopped at the block/pan rail instead of being carried through the crank cycle. Seems like that using a scraper and a pump would be a good tandem, as you have less oil flying around the engine.

Or am I looking at this all wrong?

Elarson 07-24-2015 10:23 AM

Quote:

Originally Posted by leeklm (Post 5437780)
By no means an expert here, but I cant imagine how a pump would have a significant impact on using a scraper. The scrapers job is to "scrape" oil that is being picked up and slung off the crank and rod ends. The slinging of this oil is being stopped at the block/pan rail instead of being carried through the crank cycle. Seems like that using a scraper and a pump would be a good tandem, as you have less oil flying around the engine.

Or am I looking at this all wrong?

Correct...the scraper is reducing the oil that is being drug around by the crank.

The vacuum pump is doing 2 other things....reducing the density of the air that is being drug around by the crank (saves HP) and is reducing the pressure in the crankcase so that air leaks in the seals instead of oil pushing out.

The scaper and the vacuum pump do not interfere with each other.

Eric

PONTIAC DUDE 07-29-2015 03:15 PM

Crank scraper also keep oil from climbing the cylinder walls under rpm thus less work for the oil control rings and better cylinder sealing over a period of time. ;)


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