Crank scrapers or plate...?

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Right on , have to add , Ive raced on the cheap and always noticed my small block chevys ran better when oil was low , was racing a friends 5.7l iroc and dumped a quart at the track to verify my thought and it picked up and that folks is with a 5000rpm redline.Oems are doing it for effieciency!Some people seem to get upset about cost vs benefit here , do the mopar scrapers cost that much?If so isn t it up to the one that started the thread to decide if its worth it or not for him...


Same cost for any V-8 AFAIK.

I bought the up and down scrapers with Teflon. IIRC, it was less than $200.00 and that was an easy check to write for me.
 
Same cost for any V-8 AFAIK.

I bought the up and down scrapers with Teflon. IIRC, it was less than $200.00 and that was an easy check to write for me.
That is a little more than I thought but not that bad . Lets note to the OP that the power gain even if its little is one that comes with assurance of better oil control(longer lasting engine)less prone to oil starvation when leaving hard at the line and maybe even cornering and at no cost to driveabilty/streetability!I am talking about combination of windage tray , scraper , pan with baffles...
 
I made my scraper and welded it to the oil pan on my 434, no tray.
 
one benefit to windage trays and scrapers no body brought up yet,..all of us spend untold money to balance crank rods pistons ect ect,..if ya don't control the oil in the pan and crank covered with all this oil spinning high rpm's thats added weight that's gonna effect your balanced bottom end,..the harder you spin it the worse the effects gonna be...some folks build the cheapest thay can some build the most hp thay can,..if a few hp and a better oil system that allows your crank a happier life worth the coin do it!!
 
one benefit to windage trays and scrapers no body brought up yet,..all of us spend untold money to balance crank rods pistons ect ect,..if ya don't control the oil in the pan and crank covered with all this oil spinning high rpm's thats added weight that's gonna effect your balanced bottom end,..the harder you spin it the worse the effects gonna be...some folks build the cheapest thay can some build the most hp thay can,..if a few hp and a better oil system that allows your crank a happier life worth the coin do it!!
build for enough h.p. , u don`t need all the tricks !
 
Look at the oil pan gasket for a 2.4 from a SRT-4, it has as close as you can get to a crank scraper in a production type motor. this is combined with the balance shaft housing that acts like a Windage tray.

View attachment 1715028324
Showing a scraper from one production performance engine, doesn't say how many production engines use them. Not raggin' on ya at all; it just bugs me when broad generalizations are attempted from one example. It shows the Mopar guys still had some brains when they did the SRT4.

I thank everyone who chimed in with info; I suspect many have learned a lot. It still looks to me that most all of the examples where it is clearly obvious are concentrated on the high RPM uses... where it does indeed make the most sense (to me at least).

And where you are racing, every improvement can/will show up; I lost a position in a rally by 2 seconds out of a 4 hour stage total time; I bet that scraper would have made up that difference and more. But, on the other hand, a $3k set of rally shocks would have made an improvement of 2 MINUTES... or more. Guess what I would save up my $$ for.... We ALL make cost/benefit choices all the time. I like to see sharing of the info, and letting folks decide.
 
And thanks for replying YR. If my oil temps dropped 15 degrees, it would be good in one way, but then I'd ask myself where was that heat going now!?! LOL I tend to be a believer in using the oil as another way to carry heat out (as long as the peak temps stay in control). Again, my choice because in rally, you are running large sump protector to protect the engine and trannie, and with that and a stock engine compartment, you are REALLY challenged to get heat out when you are hammering on the engine for up 30-45 minutes at a time. (The same thinking applies in favor of lighter oils; better heat flow out of the engine to a cooler.)

I know this seems like a digression, but what I am trying to show (in a poor way, no doubt) that a benefit may not be perceived in exactly the same way in another application. If the reasons to do something are known, then better decisions can be made per application. I tend try to always ask what people are going to use their engine for before answering a lot of threads; others do the same when they ask about budgets.
 
For the scraper crowd, what percentage of the crank surface (that carries oil) is getting wiped? When I got the bottom end balanced, the guy added a fixed tolerance for oil weight. In looking at a block on a stand mains up. You can wipe the horizontal edges of the throws easily, where else does it wipe?
 
For the scraper crowd, what percentage of the crank surface (that carries oil) is getting wiped? When I got the bottom end balanced, the guy added a fixed tolerance for oil weight. In looking at a block on a stand mains up. You can wipe the horizontal edges of the throws easily, where else does it wipe?
They don`t actually wipe the throws or cranks, what they do is wipe off the oil flying around the crank that is actually spinning w/ it. Dragging it w/ the crank (like a rope) costs a little h.p. and keeps oil in motion, instead of falling or draining back to the sump. not as big a problem on street cars, as it is race, high RPM engines. Girdles help a little in that department too.
 
nm9 I found my notes from 5 seperate phone calls to Kevin Johnson I took before I bought my scraper. This is the first engine I used up and down scrapers on, the first time I used a Teflon scraper on and the first one I didn't make myself. I'll never make another for the money he charges! Plus his stuff is very very nice.

Looking over the notes, the conversation totaled some 90 minutes of discussion and covered areas from entrainment to gaseous bubble expansion rates to things way beyond my ability to explain.

For me to type out a cogent summary of what is in my notes will be next to impossible if it to be understandable. When I read the notes, I understand what he was saying and how it all fits together. I don't have the writing skills to make it cogent. Most of what I would write will make no sense and it would take, probably, 3-4 typed pages to make it even close to useful for anyone.

I suggest (and always do in cases like this) that anyone with an interest in why this should be used should call IJ crank scrapers and talk to Kevin themselves. Take notes and write quick because it's like trying to take a drink from a fire hose. If he explains the science behind why oil temps can drop and that's a good thing, you'll get a better understanding than if I do it. Oil saturated with air won't cool as well as solid oil, so a scraper can make oil temps go down. Also, compresses and a scraper can reduce entrained bubbles in the oil a scraper can make oil pressure go up.

He explains it better that I can here. Worth the call.
 
For the scraper crowd, what percentage of the crank surface (that carries oil) is getting wiped? When I got the bottom end balanced, the guy added a fixed tolerance for oil weight. In looking at a block on a stand mains up. You can wipe the horizontal edges of the throws easily, where else does it wipe?


It depends on the scraper. I used the Teflon scraper and it self fits. You trim it until the crank, rods and rod bolts are rubbing the Teflon. Then as the engine runs it makes its own clearance, which is essentially zero running clearance.

Have you been to the IJ web site? There is pictures of literally dozens of scrapers and even pictures small block Chrysler scrapers.
 
yeah, I saw that but didnt see many fingers. I now see more 'ramps' that would suggest that they stick into the windage and catch oil to divert away from the crank. Food for thought...
360_dual_scraper_a.jpg


If the teflon touches to clearance itself....what exactly does it touch? I would guess the throws would be the longest piece of contact time.
CHRYSLER-LA-TEF-A.jpg
 
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The 2nd pix is posted above is the Mopar LA teflon scraper. Looks like perhaps counterweights AND perhaps rod ends and/or parts of the throws. Looks like all it removes its the outer end of the 'blanket'... which might break up the 'blanket' and let it be shed off better. But I am just guessing now....

The outer edges is where the biggest HP eater will be.
 
The 2nd pix is posted above is the Mopar LA teflon scraper. Looks like perhaps counterweights AND perhaps rod ends and/or parts of the throws. Looks like all it removes its the outer end of the 'blanket'... which might break up the 'blanket' and let it be shed off better. But I am just guessing now....

The outer edges is where the biggest HP eater will be.


The counter weights, rods and rod bolts fit themselves to the Teflon. The rod bolt is the closest but it will knock oil off the rods.

The down scraper is a cool deal too.

I guess I should have taken some pictures when I put my engine together. There is a lot of oil coming out of the bearings and rod throws, even at low speeds. Controlling it is another step in making power longevity.

My only fear was not getting enough oil on the cam from the rods but I'm told it's no big deal. First SFT I've used a scraper on.
 
With the IJ scraper sandwiched between the block and the pan, how to you handle the end seals on a small block? Do you just use lots of RTV?
 
With the IJ scraper sandwiched between the block and the pan, how to you handle the end seals on a small block? Do you just use lots of RTV?
I use lots of RTV WITHOUT the scraper set! A bit more woulf not hurt. (I like your site name BTW LOL)
 
With the IJ scraper sandwiched between the block and the pan, how to you handle the end seals on a small block? Do you just use lots of RTV?


It's in the instructions but yes, you use sealer. It's a simple fit and install. Hell, I can do it. How hard can it be?
 
The counter weights, rods and rod bolts fit themselves to the Teflon. The rod bolt is the closest but it will knock oil off the rods.

The down scraper is a cool deal too.

I guess I should have taken some pictures when I put my engine together. There is a lot of oil coming out of the bearings and rod throws, even at low speeds. Controlling it is another step in making power longevity.

My only fear was not getting enough oil on the cam from the rods but I'm told it's no big deal. First SFT I've used a scraper on.
I`m an old dog. never heard of the self clearencing (Teflon) crank scrapers ! Interesting idea, how big of "chunks?" wears off of them ?
 
And thanks for replying YR. If my oil temps dropped 15 degrees, it would be good in one way, but then I'd ask myself where was that heat going now!?! LOL I tend to be a believer in using the oil as another way to carry heat out (as long as the peak temps stay in control). Again, my choice because in rally, you are running large sump protector to protect the engine and trannie, and with that and a stock engine compartment, you are REALLY challenged to get heat out when you are hammering on the engine for up 30-45 minutes at a time. (The same thinking applies in favor of lighter oils; better heat flow out of the engine to a cooler.)

I know this seems like a digression, but what I am trying to show (in a poor way, no doubt) that a benefit may not be perceived in exactly the same way in another application. If the reasons to do something are known, then better decisions can be made per application. I tend try to always ask what people are going to use their engine for before answering a lot of threads; others do the same when they ask about budgets.
The heat will be going into the metal the sump is made of, the less aerated the oil is & the more it spends time in liquid form in the pan & not wrapped around the crank, the more
heat is transferred out of it.......cooler......and less air sucked into the pump. The windage "tray" is designed to help strip oil off the crank because of it's proximity, but it's primary
function is to do what it's name implies, prevent the aerodynamic vortice created by the crank assy. from pushing oil out of the sump & pulling it into it's path. If your spinning 3K,
this is going on, let alone 5 or 6K & up. I spun rod brgs. in a teener & a 383, every engine I have ever built since have had a least a windage tray & minimum a rear accel baffle.
Whether You see only see 2 HP, you are doing Your engine & Yourself a favor...............................
 
Good thoughts. In the case of the less aerated oil, it ought also show up in a bit lower coolant temps if it is really allowing better heat transfer by the oil. I was thinking that the crankcase and pistons will be a bit hotter since there would be less oil flung onto them...... And I appreciate oil aeration, being as I run 3 diesels and know how they sound when the anti-foaming agents wear out in the oil. (Not quite the same, I know, but you gain an appreciation.)

Siiiigh... I guess someone is going to have the break the news to J Par that he needs scrapers in that budget 360 that he is rebuilding. There goes the budget....
 
I`m an old dog. never heard of the self clearencing (Teflon) crank scrapers ! Interesting idea, how big of "chunks?" wears off of them ?


There is some fitting to do when you mount the scraper. I don't recall exactly how much it is you leave to self clearance but I think it's about .040ish.

Guess I could go pull the file and look at it but that's about right.
 
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