BlackScreaminMachine

My car started up last night, first try! It took a few minutes for the lifters to pump up, I did adjust everything with lifters I primed up with oil.

What I was wondering, and I need people with NSA/guideplate valve train people. In your opinion, which is noiser, the SA (self aligning) roller rockers, or the NSA (non self aligning) mine being Comp Cams Pro mags with Isky guide plates.

I am going to re adjust the rockers since now the motor ran, it had time to get the lifters solid.

I was just wondering if this tends to be the norm.

BlackScreaminMachine

Ok, I just went outside to do a visual recon on the car. I pulled the driver side cover. No visual wear on the pushrods, no rockers. I clearanced the lips inside the covers so no issues there. Rockers were nice and tight. But just to be sure im going to re do the adjustment so to be sure im dead on with the lifters primed up.

HardcoreRM125

Do it with the car running.

It actually is not messy at all.

I just did this today in about 2 hours start to finish, getting tools out, taking off the alternator, AIR pump fitting, etc, adjusting while it was running and up to temperature, and then reassembling. It's eay with it running, not messy, and is very very easy to establish where zero lash is.

Once the clacking sound stops, you have about 1/16 of a turn until you can feel the "jerky" twitching-ness while adjusting for your amount past zero lash. I went a little past 1/4. turn. On Poly Locks, do your preload, tighten the allen screw, then give a little snugging with the ratchet to ensure that the poly lock wont come loose.

I belive NSA are supposed to be a little louder. RR's also give off a slight, certain sound. So a little more noise with these over stock is common. Mine is pretty hard to hear anything now though over the exhaust lol.

Loadre

My NSA 1.7 Scorpions sounded like 80 sewing machines (ie - loud) Whereas my 1.6 NSA pro mags can barely even be heard.

BlackScreaminMachine

im going to re adjust to be sure, ill let you all know

BlackScreaminMachine

I will also mention the guide plates are ISKY adjustables, I got it where the rocker's roller tip is centered on the valve stem tip, I checked the driver's after the intial start up, they are still there. So maybe the clearance is is just a little tight, I have heard it on both side, sometimes quite sometime VERY loud

Stoopalini

My Scorpion 1.7 NSA roller rockers were extremely loud when I 1st installed them. I took it back apart and realized the pushrods were bottoming out on the GM guideplates I used. I took the guideplates out and elongated the slot for more clearence. They are nice and quiet now (except for the normal RR sound)

Notice the left hand slot has a half-moon mark from the pushrod hitting



You will be able to hear the RR sound standing next to the fender, and even more so with the hood open; but it shouldn't be noticable at idle when sitting in the driver's seat .....

Thomas.

ibanez6rg

NSAs will be louder than SA. With that said I really don't notice my NSA rockers.

roughneck427

Yeah ive had both NSA is not as noisy as S/A

BlackScreaminMachine

to be quite honest ive now have equal # of people saying they are as well as others that say it isnt, ill just re adjust and check back, the pushrod length is correct, checked with a pushrod length checker, so it wont bottom out, but I will re adjust to be sure

Stoopalini

Pushrod length has nothing to do with the pushrod bottoming out on the guideplate (if the geometry is correct). This happens when the pushrod angle from the lifter to the rocker's pushrod cup is steep enough, when the valve is fully closed, the pushrod makes contact with the guideplate (in an area where it is not supposed to make contact).

Also, the LT1 head's valve spacing is different than a standard small block chevy. Do the Isky guideplates take this into account?

If neither of these are issues, and your valvetrain geometry is correct, the noise you're hearing is probably normal.

Thomas.

turbo_Z

Noticed this same problem putting together a motor with my friend. We clearanced them all before running it but man every single guideplate was like that.

I have read the NSA are quieter then SA but Ive never heard SA on a comparable motor to confirm it. Mine are kinda noisy I guess. You can faintly hear them sitting in the drivers seat.

BlackScreaminMachine

In the driver seat its bearly noticable, standing next the fender, hood open I can clearly hear it, hood closed, its much less, driver seat = bearly noticable.

I guess I had to state where I am hearing the noise,

Z28SORR

Not saying any of you are wrong. But it would be interesting to hear someone try and explain this, as I see NO reason why one would be noisier??

LT4orbust

Not to get off track hear but wouldn't it be a good idea to take the new info from Vizzard into account, ie how the sa rr's outperform the nsa rr's??