Vortec self aligning rockers with solid cam

[68maliblue]

I know the right thing to do is screw in studs and guide plates but this is a very budget oriented build. Putting a set of low mileage vortec heads on a 350 with a fresh set of rings. Have a solid cam on the shelf id like to use that is fairly mild 224/224@.050 on a 108 lsa. Cam calls for .020” lash. I’ve seen some posts that this can be done with the stock self aligning rocker arms. Looking for input from any of you all that have done this.

[midnightbluS10]

I've never heard stock Vortec valvetrain referred to as self-aligning. People usually call it non-adjustable becaue you bolt it down to a tq spec and don't set lash.

[travis]

They are adjustable like any other sbc head...they just use a “guided” rocker with ears on either side of the valve tip to keep it aligned. I’ve known 4 or 5 people that have run solids with the guided rockers. You’ll have to narrow a feeler gauge to set your lash.

[Elroy]

Narrow feeler gauge like mentioned or use a dial indicator to set valve lash. I dont see any issues

[68maliblue]

Good to hear. I’ve got narrow feeler gauges. Thanks. Gives me more confidence getting info on this forum.

[dfarr67]

I have a complete set of Comp steel Ultra Pro 1.52 self aligning with studs and lock nuts- 3/8in. like new.

[rebelyell]

I've never heard stock Vortec valvetrain referred to as self-aligning. People usually call it non-adjustable becaue you bolt it down to a tq spec and don't set lash.

well, yes and no; I'm not referencing any Vortec Big Block motors because I've not laid a hand on a BB Vortec.
afaik, three iron Vortec motors: 4.3L V6 & 5.0L V8 & 5.7L V8
afaik, all iron Vortec have self aligning aka rail rocker arms
afaik, all iron Vortec V8 are Both adjustable And stamped steel w/ a ball pivot
afaik, some iron Vortec V6 are adjustable But some are Non-adjustable
afaik, some iron Vortec V6 rocker arms are stamped But some are cast steel w/ a trunnion (not unlike LS)

? The cast V6 rockers are nice but it seems they won't easily bolt into V8 heads ? If so, I'd like to learn how to simply "bolt in."

[dfarr67]

They are all the same- 1987ish up- 4.3L v6, v8, LT1 up to but not including LS. Do not use alignment plates.

[rebelyell]

They are all the same- 1987ish up- 4.3L v6, v8, LT1 up to but not including LS. Do not use alignment plates.

as above Exception: late iron Vortec V6 (was news to me as well)

GM 12555580, 12599650, Melling MR903
https://www.ebay.com/itm/NEW-Set-of-12- ... 3256043818

[dfarr67]

Looks like they need some kind of pedestal on the head to work- otherwise how do they 'lock' the adjustment. The V6 was always a little different with balance shafts, and I think it was the first to come out in vortec headed form in 1995 before the 5.7/5.0.

[af2]

Looks like they need some kind of pedestal on the head to work- otherwise how do they 'lock' the adjustment. The V6 was always a little different with balance shafts, and I think it was the first to come out in vortec headed form in 1995 before the 5.7/5.0.

They have a trough so to say that captures the valve so the heads don't need guide plates.

[rebelyell]

Looks like they need some kind of pedestal on the head to work- otherwise how do they 'lock' the adjustment. The V6 was always a little different with balance shafts, and I think it was the first to come out in vortec headed form in 1995 before the 5.7/5.0.

They do. GM 12555582 pivot support, a rack of supports, one per head, it sits on head, rockers sit on support, bolts go through rocker-thru support-into head. Dunno if it fits the earlier heads. Nothing OE like that for the V8 motors. For true, V6 was first by some 2 years or so.

[Tuner]

For lack of skinny feeler gauges you could do this. The adjusting nut and stud have 24 threads per inch. 1.000/24 = .041666 / 2 = .0208" ~~ so a half-turn of the nut gives .0208", essentially .021".

On an iron head engine I would do this overnight cold so engine temperature is uniform and with the engine not running.

Tighten the nut until the pushrod is tight to spin with finger and thumb and back off the nut 1/2 turn and that will undoubtedly be closer to .020 than most people will get it with a feeler gauge.

[Tuner]

For lack of skinny feeler gauges you could do this. The adjusting nut and stud have 24 threads per inch. 1.000/24 = .041666 / 2 = .0208" ~~ so a half-turn of the nut gives .0208", essentially .021".

On an iron head engine I would do this overnight cold so engine temperature is uniform and with the engine not running.

Tighten the nut until the pushrod is tight to spin with finger and thumb and back off the nut 1/2 turn and that will undoubtedly be closer to .020 than most people will get it with a feeler gauge.

What's wrong with you guys? Nobody busted me for overlooking the rocker arm ratio. With 1.5/1 rocker 1/3 turn should give .0208 lash from zero, or close enough.

[MadBill]

Ha! Just started scrolling through this thread, headed for the bottom to point out the ratio effect...