New camshaft, new rockers?

[d510addict]

So I am starting to gather parts for a head to be put together and am interested in putting an after market cam in. Everything that I have seen said they require new rockers, other than the occasional set going on ebay for 200 + where I can get a hold of these things?

[Sealik]

Grab some emery cloth....

 

 

 

[d510addict]

What grit? Will that be sufficient to get the ridges out ? or should I hunt some good ones down on the yard?

[datzenmike]

If a race car sure. I've swapped them and if there was any added 'wear in' it was microscopic. I might add that the ones swapped were mirror smooth and had no marks, scratches of any kind. 

 

Wet sanding on a small sheet of glass.

[banzai510(hainz)]

there used to be palces that said they could resurface them but I cant find it anymore.

soemtimes ratsun memebers have spare sets they sell for 100$ or so.

 

cam really work best if you have sidedrafts. So be sure if you really want to do this up grade and you got to do it right. rockers and lash pads and retainers.

 

 

to me bolting a 38/38 carb is a bigger improvemnt(also only 4 bolts) than say a bigger cam and just a 32/36 progressive. Esp if you got a L20.

[racerx]

a lot will depend on what D510addict is planning with the car.  If it's daily driver then stock cam and 32/36 weber is sufficient. As far as rockers are concerned, go on line, I've seen them but can't think of name for now.

[Xnke]

Call Delta Camshaft...they resuface them for 4$ or so each.

 

And yes, you do need to resurface them, or you will risk a cam lobe going flat. The only sure way to avoid it is get them is new/resurfaced rockers, a REGROUND (NOT a new core) cam, and quality oil.

 

The CWC billets don't hold up well, and the new cam cores that DO hold up are rare enough that I can't reccomend anything but an OEM cam, reground to the new lobe profile.

[d510addict]

Well this is for a dd, but i am replacing the head when i can find a decent one to build up and tbh i am not too happy with mu 32/36 my holley 2 barrel provided more than it, but that carb wasshot.

[banzai510(hainz)]

I think muy Scneider and my Webacamshaft are CWC billets.

My Schneider is doing fine.

 

i dont trust delta t regring unless you have a Mic tool right there.

The cams(3) I got wer not as spec. I gave them away.

 

My banzai 510 has a delta but never measured it. Suppose to be a Isky clone 475/275. seem ok but one can tell its wearing.

 

I hear regrinds if they didnt harden it correcly it could be softer inside.

 

But this is just all info.

I think most new cams are not going to be made anymore anywasy unless its new old stock lying around.Scheider is regrinds only now and webcamshats dont have the bigger grinds avail new anymore.Isky might still have soem but heard those might be gone also.Erson and other might still be out there.

The days of the L motor are getting less and less

[Xnke]

All the Delta Cams camshaft profiles for the L-series engines are oversold on lift numbers. They're all spec'ed out based on 1.6 rocker ratios, which aren't available. Stock is 1.48, and there is a 1.53 ratio rocker out there...I have ten of them and need to find two more. Only way I know how to find them is stick them in the head and measure the valve lift, some come out higher than others, consistently at the 1.53 ratio.

 

That said, the CWC billets work fine in some engines, and fail in hours of run time in others. All of them fail in the same way, the cam lobe wipes off and the rocker arm has a pitted, veined look to it. It's caused by improper oiling, not the amount of oil but the composition. The nissan factory cams are much better about tolerating less than ideal oiling conditions, but even they won't last long if you aren't running oil with a EP additive package.

 

CWC is not going to supply the new cores much longer, because it's finally coming back to them on the lack of good metallurgy. Once the current stock is depleted, they're out of the game. The only route to a new billet will then lie in Japan, and they ARE available if you are willing to buy them. Last I checked the new, unground billets were not a catalog item, but instead you had to convince the big "K" that you wanted to buy the unground cores. Both L4 and L6 cores are available...and can be identified by the large hex-shaped wrench lugs cast into the shaft, as opposed to Nissan cores with two square lugs, and an unknown source that has a small, shaft-sized hex on the core.

 

New rocker arms are relatively difficult to get, but again, the big "K" has them too. These hard to find items aren't hard to find in the homeland.

[banzai510(hainz)]

I have 3 sets of Atsugi rockers.<br />Mr Auto-parts.com had them but hey went out of bussiness. Just wish I knew how bought up the parts. as thay had a count of how any they had.<br /><br />I got 2 extra cams at home I think Im good.<br /><br />Lucky Schneider and others do regrinds<br /><br />Delta Cams should say their cams are not as spec. People spend alot of money thinking they getting a bigger cam and find out you just getting stock lift and maybe a longer duration.

[Xnke]

I'm not saying they're stock lift...although some of them are. They ARE accurate on duration numbers, and they are correcting the catalog a little at a time since really, how many datsun cams do they sell every year? Not that many.

 

Ever mic'ed an Isky cam? It's not exactly to spec either...but it's close. Isky cams are spec'ed with a rocker ratio of 1.48, where delta cams are advertised with a rocker ratio of 1.6. Just take the lift number, divide by 1.6, then multiply by 1.48 and that's the *real* lift number, PLUS the valve lash. Of course, this only applies to un-used cams...as soon as you start the engine, the initial wear will change the lobes a little, and using the wrong oil or an improper valvetrain geometry can REALLY reduce those lift numbers in a hurry.

 

So, even a fully-cut-to-spec cam of let's say 0.490" lift, will only lift the exhaust valve 0.480" cold with the lash set properly. Keep in mind too, when setting up a cam and getting disappointed over lift numbers, that HOW the valve lash is set will determine the rocker ratio, the overall duration, and the total lift for that cam too. 0.002" in lash can make a pretty significant difference in how well an engine runs with a given cam...some cams love it, some don't give a shit, and some cams NEED to have the lash set correctly or they lay down and play dead.