Datsun Roadster Forum-311s.org

So with the pan off checking the rear main seal (which seems fine... damn, it better be!), thought I'd bring this back up. If I get one I'll let you know what I think. Would go steel, not willing to pop for Teflon.

If you look at some of the customer testimonials on their website, Russel Roach racing a Roadster installed a scraper.

I just ordered one, should be here in a week or so. The owner, Kevin, said another Roadster owner had just ordered one too but he didn't recall the name. I'll post pics etc when it arrives.

I loaned Kevin three different engines that he used to mock up the scrapers with, and in return I got a couple of them. I have not installed them. I know that you have been doing a lot with your engine and have a good handle on power adders, so I am watching with interest to find out what your results are.

spl310 wrote: Sat Mar 20, 2021 5:45 pm I loaned Kevin three different engines that he used to mock up the scrapers with, and in return I got a couple of them. I have not installed them. I know that you have been doing a lot with your engine and have a good handle on power adders, so I am watching with interest to find out what your results are.

Ya, unfortunately it won't be the only change made to the motor the next time I'm on the dyno: Better sealing valves, drop in compression from 11.7 to 10.3 with some timing changes likely, addition of EFI going from 37mm ventures in 45mm carbs to 40mm throttle bodies (the big game changer I think) and then the scraper... oh, and Daryl's post on anti-reversion in the exhaust pipe has me interested... but I don't think I'll be able to say if it helps or not unless there's some kind of "feeling." It may show up in oil pressure or engine temps, but very limited data there!

I love that show "Engine Masters" where they make one change at a time on their test engine and run it on the dyno to see results. I believe they did play with the amount of oil and found significant hp changes. I would love it if they would do scrapers. Maybe I'll write and ask them. Fun stuff.

The scraper arrived the other day. Very solid piece of steel. After test fitting it it was clear I would need to open up several of the bolt holes as they were off just enough to concern me about interference when installing the pan, some more than others. No problem to modify them with a proper step bit. I replaced one bolt with a stud that I happened to have to function as a locator for the scraper, along with the front studs.

I just bolted the head back onto the block but have not yet spun the engine to check for clearances. So far it looks really good. Once I'm satisfied it's not gonna rub, I'll use the super duper Toyota gasket maker and seal it to the block, then more sealer, gasket, more sealer and then the pan with locktite on all the bolts.

I expect 500 more horsepower.

Greg, I think you forgot a zero....a very tiny zero just like the four that precede this sentence. Oh, yeah, it goes on the lower left corner of the 5

that things got to be a tuning fork there ....watch out

redroadster wrote: Wed Apr 21, 2021 8:59 pm that things got to be a tuning fork there ....watch out

That's the truth... lots of very careful clearance work going on... and on...

When I was the performance tech at Mitsubishi
( I tested vr4s , eclipse turbos and Evos that owners were not happy with the power ) The Mitsu North America trainer would call to talk it over with me He told ...that on Evos in the Dakkar races they had a vacuum pump driven off the drive shaft that sent vaccum to the crank case
5-10 psi neg on bursts giving big hp gains
and certain models of Evos where to get this system , it never happened in US though

So it's in, but I gotta say it was some effort to make sure it never scrapes the crankshaft. I don't blame the product as much as the uneven finish on crank weights, but the scraper does need some more time spent refining it. Pretty much every clearance area needed work, and I ended up deciding to remove 3 of the little prongs because I was more concerned about it not hitting than scraping every bit of oil off. But let's face it, not likely that there's a big demand for U20 crank scrapers so I'm not surprised it needed work, and I'm sure every scraper requires at least some.

I used the Toyota sealant, bolted it down, let it set, then unbolted it, added the gasket and sealant on both sides, then bolted on the oil pan. It appeared to seal well but only oil and pressure will tell us!

Would I recommend this? Well, without experiencing some observable or measureable gains and based on the amount of work, I don't think the average owner would find it worth the effort. Now, if I experience some improvements that I can attribute to the scraper, I'll let you know. I know my engine pretty well so we'll see!

The crank being invisible... @30- 100 revs per second, seems most oil would be slung off
I like to watch oil on L series eng. come off in a BB size drop and stay that way race down the drain

The oil IS being slung off, but it is effectively a rope and is inducing drag on the reciprocating mass. The scraper cuts that oil off so that it effectively lightens the mass. Or so I am told...

spl310 wrote: Fri Apr 23, 2021 9:01 am The oil IS being slung off, but it is effectively a rope and is inducing drag on the reciprocating mass. The scraper cuts that oil off so that it effectively lightens the mass. Or so I am told...

Yep , that's the theory. A thick cloud of tiny drops is created. With today's technology, seems that this could be captured by video so we could see if it happens and what the effect is before and after scraper. I just hope that when I push the clutch in and the crank shifts slightly it doesn't start ticking! I wanted to make sure I had clearance under all circumstances.

I have seen a video, but cannot locate it now.