Jeep Strokers

I was talking with the machinist today about doing the lifter bore grooves and he was concerned that they were going to be too deep.

Then then showed me a cam on a Nissan(IIRC) head that he had there. That cam had a system where oil would be pushed up through a hole in the cam lobe. He recommended that instead of using the lifter bore groves that we do something like that. It would involve gun grilling the cam shaft with about a 1/4" hole then drilling a small hole in the lobe right before the ramp, centered under the lifter. Then drilling a hole in the cam's journal (#3 or #4 iirc, which ever bearing has the groove, not number one though) to allow oil into the gun drilled tube and out to the lobes. This would basically duplicate the oiling setup on the Nissan.

Any opinions on this? I would be concerned about it weakening the cam. Not really concerned about dropping the oil pressure as either way I will have some form of extra cam oiling.

Interesting??? Do you know what year and size Nissan engine? Any pics of the Nissan cam?

Or instead of drilling the cam, you could make a oil spray bar like this...

An oiling bar that is hooked up to the oil pump relief valve, so all bypass oil goes to the cam, and none of the pressure lube oil is effected

dwg86 wrote:Interesting??? Do you know what year and size Nissan engine? Any pics of the Nissan cam?

No, I don't know what year of the Nissan, and a Google image search found nothing of use. I will be stopping by there tomorrow and if he still has the head I will get a pic.

dwg86 wrote:Or instead of drilling the cam, you could make a oil spray bar like this...

IMG_2142Large.jpg

He did mention something like that. He said that BMW used a similar setup. He said that we could drill into the lifter oil galley and route some pipes... or something similar to an older windshield washer sprayer (at least like on my old Jaguar, with two nozzles on one main fitting.) Seems a bit finicky to me to set up and in the case of out 4.0L gravity would be working against it and you would need to position the nozzles 100%.

I am also concerned about how gun drilling the camshaft would effect the balance of it.

Mgardiner1 wrote:An oiling bar that is hooked up to the oil pump relief valve, so all bypass oil goes to the cam, and none of the pressure lube oil is effected

But when does that valve open and would send oil to the bar?

You could just use camsaver lifters or groove the lifter bores and use American made lifters. Make sure your rod bearings have the notch in them to spray the cam, use zddp addative and you will probably be OK. I'm not trying to discourage you from looking at other ways of lubing the cam, but I would think it would take a lot of time and research to make sure everything is right.

Would a spray bar work? Would you have to use a high volume oil pump? You would have to find out what size oiling hole to use, and make sure it wouldn't effect lubing other parts of the engine (bearings, top end).

I would think drilling the cam would weaken it. Would it weaken it enough to cause it to fail? Maybe, maybe not. I wouldn't want to find out on an engine I just spent a bunch of money on.


Just my 2 cents.

dwg86 wrote:You could just use camsaver lifters or groove the lifter bores and use American made lifters. Make sure your rod bearings have the notch in them to spray the cam, use zddp addative and you will probably be OK. I'm not trying to discourage you from looking at other ways of lubing the cam, but I would think it would take a lot of time and research to make sure everything is right.

Yes, I know all about the ZDDP, bore grooving and camsavers. I don't believe that the camsavers do anything because the lifter is constantly rotating, and it won't be over the section of the cam that needs the lube that often. I have used a set and I also didn't like the finish on the bottom of the lifter, compared to the comp cam lifters the finish wasn't that nice. I haven't dismissed lifter bore grooving yet, we just need to see how deep the universal cuts the groove, I may get the more expensive tool instead of the universal, as the depth is adjustable on that. What will probably be done with the universal tool is a small test cut done in the bore just to see how deep it will cut. From what I have found the ideal depth is .010".

As for the US made items, I have a Nitrided CompCam shaft and their lifters. I'm just trying to eliminate any possible engine failure point that I can.

Would a spray bar work? Would you have to use a high volume oil pump? You would have to find out what size oiling hole to use, and make sure it wouldn't effect lubing other parts of the engine (bearings, top end).

For lifter bore grooving I don't believe a HV pump would be necessary. I am basing this on my use of the cam savers, where I noticed no oil pressure change when I installed them. As for the other methods I don't know.

As for lack of lube to other engine parts, how do I determine that?

I would think drilling the cam would weaken it. Would it weaken it enough to cause it to fail? Maybe, maybe not. I wouldn't want to find out on an engine I just spent a bunch of money on.

I agree.. don't want to be a guinea pig for a broken cam. Especially with all this talk of cam harmonics, who know what it would do to that.

do you realize what a gun drill is cost? i am in a town where there are many many many good and rather large and small shops and its hard for me to get that process done myself. something to think about.


steve-o

I will know the cost tomorrow or Friday. The Machinist knows someone that might be able to do it

gremlinsteve wrote:do you realize what a gun drill is cost?

I found some decent condition used gun drilling machines for around $40-50k.
If I had that kind of spare change... I'd have the roller cam and lifters in production already.

yea. i had some work done for the shop not long ago...liked to killed my account when i got the bill.
they where not cheap. its a hard thing to do. and on a case of one-sies and two-sies...it would be hard to find a shop that has the time to dop it. around here that is.

steve

SilverXJ wrote:

Mgardiner1 wrote:An oiling bar that is hooked up to the oil pump relief valve, so all bypass oil goes to the cam, and none of the pressure lube oil is effected

But when does that valve open and would send oil to the bar?

The only time that relief valve probably does not have oil being pushed out is hot engine, at an idle, like when you can watch a oil gauge drop down to 5-10 psi

That is what I was afraid of. I don't think that hooking up the oiler bar to the relief valve would be an ideal setup as at idle you don't have that splash action going on and you wouldn't have the extra oil from the oil bar.

Just a few images of the holes in the Nissan cam. The machinist wasn't there the day I took the pics, but his helper said that head originally had an oiling bad, but nissan changed to the holes in the cam lobes.