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post #21 of 40 (permalink) Old 03-19-2007, 01:49 PM
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Re: Crank Scrapers

"If I misunderstood the need for return shipment then I apologize for that mistatement

But basically you still sent me a part the first time around that was misadvertised as a stroker crankshaft scraper. You didn't do the proper research before selling a part that was not suited for the stated application.That's a poor business practice in and of itself. Yes you offered to fix the problem, but it should have been at least close to being right for the application when you first sold the part.
When all was said and done I was able to adjust the part to within the 1mm limit you described and I only had to build up two of the areas with epoxy.

Also you keep missing the point that I have stated that crankshaft scrapers have been shown to work in some engines. However, it did not show any benefits in my particular engine.

If you have emails from individuals with L6 series engines who have seen track times improve or HP improve on a dyno after the addition of your crankscraper then please post those in this thread as a counter to my own experience."



The rod cutouts were moved outwards by 1/2 the stroke increase. There was no misadvertising there, sir. I did ask the person who lent me the blocks whether the counterweights were the same -- he thought they were.

We have probably over a thousand stroker patterns -- people ask for them all the time. That's not counting the innumerable aftermarket rod patterns. The pro shops I speak to acknowledge that adjusting scrapers is normal. They have made their own and know what's involved. Maybe after making thousands I know too?

My experience in pulling apart -- and measuring -- hundreds of different engines spanning 50 years and getting feedback on thousands of patterns is that there is a large amount of variance even amongst parts with the same part number.

Have you ever measured the swept path of eleven diesel stroker cranks from Nissan? Well, I measured eleven precision pressure cast sumps from Ford with the same part number spanning 5 years production. There were three distinct groups of casting gate dimensions. Similar results have come from measuring BMW components and Mopar parts. All these measurements interfered with scraper desgns.

I spoke with a gentleman from Cosworth Engineering about it and he related that pattern makers are often left to their best judgement as to how to set up molds within given parameters.

As to your particular engine:
Here is what I did to get any semblance of experimental method when measuring the scraper in the Metro. The G10 scraper has the same general design and attachment method as the L28. I left the scraper in place when I had the baseline dyno run. Immediately after -- the car still strapped on the dyno -- I went underneath and drained the oil into a container. I removed the oil pan and the scraper. I replaced the pan and poured the same oil back into the motor.

This took about 30 minutes total so the ambient weather conditions were the same. The gas was the same; the tires and tire pressure were the same; the oil filter was the same; the oil was the same; the plugs were the same; etc.

No butt dyno involved. All the things I mentioned above, and more, could easily affect your output by 2% to 3% and mask or enhance the increased output due to a scraper. They are called confounds.

So, how does your experimental technique and rigor compare?

As for other L28 owners, well, how about this: When I picked up the blocks the owner had a Nismo competition pan and showed it to me. Scrapers all over.
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post #22 of 40 (permalink) Old 03-19-2007, 02:04 PM
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Re: Crank Scrapers

I had to do a ton of modifying around the around the rod bolts so that was NOT anywhere near what you stated. Also I had to grind away to keep the sides of the counter weights from rubbing on the scraper aswell.

I run the L28 rods with the LD28 crank instead of the L24 rods and I told you so in my first email from ebay. I saved that email

------------------------------
Dear sammi1228,

Hi ,I have an LD28 crank in my Datsun with the stock 280Z rods. I am interested in your crank scraper and wanted to know if you have one in stock and how soon it would be shipped out if I purchased it today and paid via paypal. Thanks,Norm(The 12 Sec Dual SU Dude)

--------------------------------------

So you didn't bother accounting for the fact that a shorter rod would stick out more at the bottom and hit the scraper.

Like I said earlier stop attacking me for merely relaying my own experience and instead post emails from people that have experienced documented numerical gains from using your L6 series crankshaft scraper, Also I would like to know if it fit correctly the first time they installed it.

And I don't use BUtt Dynos. I use established track times from ten years of racing my car. I know if a product has helped or hurt my times merely by comparing my track times and equal ambient weather conditions as well as 60 ft times 330 ft times and 1/8 mile times.


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post #23 of 40 (permalink) Old 03-19-2007, 02:49 PM
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Re: Crank Scrapers

"I had to do a ton of modifying around the around the rod bolts so that was NOT anywhere near what you stated. Also I had to grind away to keep the sides of the counter weights from rubbing on the scraper aswell.

I run the L28 rods with the LD28 crank instead of the L24 rods and I told you so in my first email from ebay. I saved that email

------------------------------
Dear sammi1228,

Hi ,I have an LD28 crank in my Datsun with the stock 280Z rods. I am interested in your crank scraper and wanted to know if you have one in stock and how soon it would be shipped out if I purchased it today and paid via paypal. Thanks,Norm(The 12 Sec Dual SU Dude)

--------------------------------------

So you didn't bother accounting for the fact that a shorter rod would stick out more at the bottom and hit the scraper."

--------------------------------------------------------------------------------

Think for a moment about what you wrote.

You're subsuming that I would assume that people would use the L24 rods and that your use of L28 rods was unusual.

No. When I make stroker patterns for stock rods they are for the stock rod pushed out by half the stroke increase. That's what you got. It works out to be 2mm.

I do currently offer a service sending out CNC cut plastic templates to be modified and returned or scanned and the file emailed back. That is basically done at cost: $25.

__________________________________________________ _


"Like I said earlier stop attacking me for merely relaying my own experience and instead post emails from people that have experienced documented numerical gains from using your L6 series crankshaft scraper, Also I would like to know if it fit correctly the first time they installed it.

And I don't use BUtt Dynos. I use established track times from ten years of racing my car. I know if a product has helped or hurt my times merely by comparing my track times and equal ambient weather conditions as well as 60 ft times 330 ft times and 1/8 mile times."

__________________________________________________ _

Oh, so you ARE controlling for all those other variables? Yes, I know about the technique -- it involves scientifically changing one part at a time and then comparing track times back to back on the same day hopefully.

You are still the biggest confound -- subconsciously you may be running consistent times like a bracket racer regardless of parts change. Do you have datalogging?
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post #24 of 40 (permalink) Old 03-19-2007, 03:05 PM
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Re: Crank Scrapers

Kevin I am done arguing with you.
As I said I saw no increases.If you have facts to back up your claims on other L6 series engines then post them.
You will sell a lot more scrapers by showing statistical results of others who have benefited from your product than by merely continuing to attack one person who says he did not benefit.



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post #25 of 40 (permalink) Old 03-19-2007, 09:29 PM
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Re: Crank Scrapers

Norm wrote:

"Kevin I am done arguing with you.
As I said I saw no increases.If you have facts to back up your claims on other L6 series engines then post them.
You will sell a lot more scrapers by showing rstatistical results of others who have benefited from your product than by merely continuing to attack one person who says he did not benefit."

--------------------------------

I just got back from the airport and have a bit more time to write now.

It is difficult to do a core dump on you so I'll try to work around the edges.

I did the dyno testing on the 993cc three cylinder motor to answer and bracket the critics who said, "yeah, it works on V8s but not small four cylinder motors."

Then there were (and are) the people who say that it works on high revving engines but not under 4000 rpm. They should be relocated to a remote island with the former group to get their story straight.

As it stands now, that design of scraper is used by Dodge as OEM on the Viper V10 engine and I have results from a straight three. Oh yeah, I forgot -- that design is also cited by GM in a recent patent application. That all kinda means it is accepted as sound engineering and assumed background knowledge for specialists in the field.

Now to your engine, the Nissan straight six of about 35 years vintage.

The easiest thing to do and explain is that YOU need to do a within and between groups longitudinal analysis of the windage control design trends by professional automotive engineers, including those from Nissan.

Start with Nissan. There is nothing particularly special about the straight six versus the straight four. Look at the L-series as it has progressed and then look at the KA engines then the SR engines. More and more windage control including massive use of scrapers -- that covers about 35-40 years.

Look at the development of the straight four and six from BMW and Toyota that occurs in the same time period. Blocks completely redesigned to minimize windage. In windage terms, the L-series is back with the M20 and M30 and 5M and 6M of about 15 to 25 years ago. You need to examine the design details of the move into the M50 series engines and 2JZ series respectively. Things are even more advanced now but that's too much to absorb all at once.

You'll notice that I said YOU need to do the analysis. This technology is well proven -- I've simply done my homework -- a huge amount -- and you haven't. You need to explain why your engine deviates from and is exceptional to sound design practice for windage control. I understand that you don't think about windage control for most of your waking hours but I do and I take it very seriously.

Somehow you've constructed in your mind that it is my responsibility to explain why you don't see positive results. Frankly I don't have that sort of time. I have given you some possible problem areas with your experimental technique to think about.

Kind regards,

Kevin Johnson
Ishihara-Johnson Crank Scrapers

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post #26 of 40 (permalink) Old 03-19-2007, 10:20 PM
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Re: Crank Scrapers

Uh NO I didn't ask you to explain anything because I know it works IF it is designed properly.
What I asked you for was testimonials from actual people who used your product and had no difficulty with the installation.

Please provide those emails from actual L6 engine customers and then you should have no problems selling your product.


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post #27 of 40 (permalink) Old 03-20-2007, 12:55 AM
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Re: Crank Scrapers

"Like the apes on "2001" they all sit there scratching themselves and screeching at the occasional interloper that tries to show them how to make fire."

Far more important is how to build that raft to get off the island, I should think.

;-)
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post #28 of 40 (permalink) Old 03-20-2007, 02:20 AM
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Re: Crank Scrapers

Yes ,provided of course is that the raft is designed properly and doesn't come apart drowning the critters....haha


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post #29 of 40 (permalink) Old 03-20-2007, 03:09 AM
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Re: Crank Scrapers

Godspeed.
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post #30 of 40 (permalink) Old 03-20-2007, 09:53 AM
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Re: Crank Scrapers



I will waste a couple more minutes with this.

Norm wrote, "Uh NO I didn't ask you to explain anything because I know it works IF it is designed properly."

You know nothing of the kind, sir, I am sorry. It is a very easy thing to claim but to someone who does know yours is utterly transparent. If you personally check the clearances of the V10 Dodge scraper you will find it comes no closer than 2.5mm to the rotating assembly.

Let that be a starting point for your studies.

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