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JoeMag 04-17-2009 05:31 AM

Cross drilling crankshaft.
Looking into the process that CCR (Armando) does on crankshaft cross drilling to get more oil to center rod journals. ...never really looked much into crankshaft stuff so no really familair with this.

Is this the correct option? Other's experience with this?

JoeMag 04-17-2009 07:27 AM

Ok... did the search and the general consensus is it's a good mod. Anyone used CCR (Armando) in CA?

neilca 04-17-2009 12:50 PM


How much does Armondo charge to cross drill a crank? I have had this done on other motors in years past (by other machine shops) with good results.

SteveWig 04-17-2009 04:07 PM

I had Armando cross drill my 3.2 crank a year or so ago. Ted Robinson at German Precision highly recommended the process and Armando for the engine I was building. I had him inspect, magnaflux, micro polish, and the cross drill modification. The price was very reasonable and since he was local I was able to see his shop and spend some time talking with him. He showed me crankshafts from numerous Porsche race teams from all over the country. I think you will be in good hands.


Henry Schmidt 04-17-2009 05:14 PM

Good mod. We cross drill evry crank in our shop.
2.0 T to 997 GT3.
Our super crank is cross drilled on every main journal.
More oil at the rod bearings is always good.

TimT 04-17-2009 06:05 PM

Replied on rennlist :cool:

ajwans 04-17-2009 06:15 PM

Anybody care to provide schematics on how this mod should be
done, I'm in Australia so I'll need to get my local machine shop
exact instructions.


Henry Schmidt 04-17-2009 06:16 PM


Originally Posted by TimT (Post 4612996)

Interesting post.
Proof positive that opinions will vary.
Anecdotal stories about how a part functions does not negate the superior oiling of the more modern design of a cross drilled crank.
Let's see if I understand one of the complaints, "I would never cross drill a crank because you have to clean the crank after cross drilling?"
Ninety percent of all crank failures in large journal cranks is poor oiling on #2 & #5 bearings.
The GT3 crank survives at high RPM because of the small journal and a huge pump. The first thing we do to a new GT3 crank is cross drilling. Necessary? maybe not but it's cheap and on paper makes sense.
If we are trying to run a large journal crank under greater than average stresses it's foolish to ignore crossing drilling.

TimT 04-17-2009 06:22 PM


Interesting post.
I agree.

bob barnes 04-18-2009 06:00 PM


It will be cheaper in the long run to ship the crank to CCR and have Armando do the work. Many mistakes can be made by some machine shop learning how to vs. someone who has performed the work. Getting a clean crank returned with plugs
fitted not to come out can be a problem for the machine shop not familiar with the procedure.

CCR is a crank expert-period. Money well spent. Since using CCR, I have not lost a rod in any of my Race motors turning 8000RPM+.

Henry, we are for once in agreement! Must be a new beginning.


Henry Schmidt 04-18-2009 09:01 PM


Originally Posted by bob barnes (Post 4614472)

Henry, we are for once in agreement! Must be a new beginning.


Over 3000 posts and this is the first one you agree with?
Welcome to the light.:)

turbobrat930 04-18-2009 10:46 PM

I will also put in a plug for Armando at CCR... AWESOME job... the crank will come back to you looking like jewelry!!!!

BReyes 04-25-2009 08:04 AM

Yes I too have heard the best regarding Armando.

Hey guys (specialized question) what about knife edging the crank. Seems like a while in there mod (specialized sit). Thx.


HawgRyder 04-25-2009 08:17 AM

Knife edging the crank for those not in the "know" is making the leading edge of the crank counterweights come to a sharp knife-like surface.
I have done this on many engines for drag racing purpose, but usually combined with a "windage tray".
The tray is a piece of metal...usually aluminum cut to the profile of the crank as it revolves.
The tray ends up looking like a bunch of fingers coming from the bottom edge of the crankcase pointing towards the crank.
The whole idea is to strip the oil off of the crankshaft instead of letting it flail around and create oil mist or foaming.
In our case, with the flat six, I doubt it would be easy to do and probably not do anything beneficial.
The knife edge will cause less friction or drag, but also of debatable benefit.
My $.02

turbobrat930 04-25-2009 09:24 AM

I mirror Bob's comments above, and will add this:

Our engines are dry sump. Knife edging usually is done to reduce the friction of the crank cutting thru the oil in the oil pan. As Bobn stated above, used in conjunction with a windage and/or sraper tray, it can be quite effective.

However, when our engines are running, there is very little oil in the botton of the case, as the oil pump in the dry sump system, is very effective at removing the oil.

For an all out race engine, where you have money on the line if you win or lose... then go for it. But for a street car, DE car, or even a PCA racer... I would doubt that it would be worth the extra cost.

JoeMag 04-26-2009 07:08 AM

Neilca -- sorry i missed your post. if i recall, it was a few hundred $'s to cross drill and work up. I ended up picking up crank that he already worked up, so I don't recall exact numbers. Armando's number is 650-342-0568. ...I had to laugh when I called him, he answered the phone something like "how's it going up there?" He's in CA and i'm in Cleveland, OH.

Dr J 04-28-2009 05:09 PM

I recently rebuilt and decided to cross-drill. Haven't assembled it fully, but once the case is open, for a few hundred bucks, I figured it would be worth it. I'm not planning on having to open it again for another few decades or so, so why not.

bob barnes 04-28-2009 05:55 PM

To properly have your crank prepared for racing, it may be more than a couple of hundred bucks. The crank should be checked, mag, cross-drilled, flushed and cleaned, plugs carefully installed, Balanced, micro-polished, and rechecked. Budget $500.00 to have a good job done! This is not a one hour job. Labor rates in the bay area is >$100/hr. The cross-drill is a portion of the total cost to do it right.


SteveWig 04-29-2009 09:28 AM

I went back and looked at my receipt from Armando at CCR. The work was done in July of '07 so his pricing may have changed.

Clean and magnaflux
Mic' journals and check for straight
Cross drill #4 main and chamfer oil holes
R & R oil line plugs
clean oil passages
make new plugs and install with loctite
micro polish
complete balance to less than 1/2 gram

All this for less than $500 (I'm local so no freight was involved). I felt this was a bargain compared to everything else I was spending on my rebuild.

Henry Schmidt 04-29-2009 09:45 AM

If the crank is crossed drill without a groove you must groove the bearing. We also drill the bearing feed hole all the way to the case main oil galley. By enlarging the feed hole we guarantee that a sufficient amount of oil is supplied to feed all bearing adjacent to the # 4 main.
The last step in the process are cam feed line restricters. This ensures that a plethora of oil is present in the bottom end at all RPM and temperture ranges.

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