Carl Fausett

Thought you might find this interesting...

We are developing a crack scraper and windage tray system for stroker cranks, and here are a couple pictures to show the process.

These are a mod to the crankscraper and windage tray system we co-developed with Ishihara-Johnson several years ago, and when I have the patterns finished these will go to IJ for manufacture like last time.

In addition to making changes for the longer stroke, we are also relieving the scraper for the larger bearing boss of the steel rods we are using in the big engines. This one is a 6.4L build.

The yellow marks indicate where more material needs to be removed, then I take the scraper off and into the shop to do so. The paint marks are burned off. The scraper is deburred and cleaned, then brought in for another fitting, and the process starts again.

IcemanG17

nice looking crank......but I gotta ask....are the bores a liner motor before the liners are installed?

GregBBRD

You say that the leading edge is pointed to reduce wind resistance.

It appears that the knife edge is on the trailing edge and the rounded edge is on the leading edge of that crankshaft.

Are you also switching engine rotation?

blown 87

Good question.

Carl Fausett

Greg? You realize you are looking up from the bottom, right? Look again, thats CW rotation. The front of the engine is on the left.

Brian?? I dont understand your question.

blown 87

The picture in the second post has the block drain plug to the left, on my car that is at the back of the engine.

I guess I do not understand all I see here, it really does not matter if the engine is viewed from the bottom or the top.
if the drain plug is in the back of the block and the V is the leading edge then it is a CCW rotation.

I am not trying to be combative or anything, but it sure LOOKS like it turns the wrong way.

Rob Edwards

The engine stand is on the left, as is the locating sleeve around the rearmost M12 girdle stud. Isn't that the back of the engine?

slate blue

To the best of my knowledge the most aerodynamic shape is a teardrop, as such you want the rounded surface leading with the tapered point trailing, if I am wrong about the teardrop, ignore what I just said.

I have written an post on my research about crank design I may post it soon.

Greg

blown 87

If the V is not the leading edge, then it is a cw rotation.
one side is a knife edge and one side is not, but the left on the pics is not the front of the engine, any way you want to look at it.

As far as being aerodynamic, a f104 wing looks a little different than a PA-28 wing does, but both are aerodynamic.

IcemanG17

Carl
I was wondering about the finish in the cylinder bores? It looks like there is quite a bit of finishing still left to be done?

Rob Edwards

I don't want to put words in Carl's mouth, but that cylinder bore finish looks a lot like a Nikasil finish. (EDIT: I Fail, those are steel liners, see post 13)

JKelly

Carl Fausett

John: maybe read the whole text and not the first 6 words?

Brian: the finish does look different than what you are used to. Good eyes. This engine is bored and sleeved to 4.125" bore (104.7mm). So what you saw was steel sleeves. The bore plus the stroker crank is what nets 6.4L

All: I just wanted to let you guys know (if you are interested) that we are working on the crank scraper pattern for a stroker scraper, and our patterns will be going to IJ. I did this also for the last revision of the IJ crank scrapers for the 5.0 motor several years ago.

ptuomov

I have a question about the scraper. There's a scraping blade on both sides of the crank. When the crank turns and whips oil with it, one of the blades will scrape oil below the blade and into the sump. That's good. However, the other blade will scrape oil above the blade. How will the system guide this oil that is scraped onto the upper side of the blade into the sump?

Mike Frye

Carl,

Thanks for developing and posting this stuff. It's great to see that you and your team are looking at every possible issue that is a strength or weakness of the 928 and trying to improve it.

Your experience and technical expertise are great for the community.

I'm always surprised when I see someone who actually races and builds these cars come on here and post their efforts only to be criticized and picked apart, often by those with less knowledge or personal experience.

I understand that's what these forums are all about and opinions are like, well, everyone's got one.

Just wanted to chime in for the silent ones out here who aren't likely to build a stroker motor any time soon, but really enjoy learning about the ins and outs of the process from those who are doing it. I've bought several of your kits and modifications and I plan to continue to do so.

Keep up the great work.