426 g2 Hemi Correct Size Valve Locks

[70rcode]

Anyone know correct size valve stem Lock size ? Depending on Specific lock manufacturer/Brand, the long time fractional spec 5/16" Dosen't seem to be Correct ? What size(s) is Correct to prevent dropping a valve ?

 

[fbs63]

Decimal for 5/16 is .3125. Most manufacture's make them .310 to .311.

 

[PRHeads]

Many of the G2 hemi valves are actually .307-.309.

Measure your stem diameter to know for sure what you have.

 

[IQ52]

Yes, measure carefully. That is why God made micrometers. I once got a prepped set of hemi heads in here built by a big name hemi builder that had mixed up and different size locks scattered throughout the assembled heads.

 

[70rcode]

Dang right, mike the hech otta them hemi stems 'cause yu can't trust anything now! Then what ? Most V-lock sources you look up, you're Not gonna find Your Number Now What ? Round off, Safely (no valve drops allowed) how much & which Way ? But i Mike'd them & i Shouldn't have to "round" anything & if everybody is "rounding"(who knows which direction & Loose don't seem good), what good did using the "good" mike do ?

 

[70rcode]

Most every motor part i can mike & measure independently, but how do ya accurately mike a V-stem lock's inside-d besides eyeball comparing to a known good identical lock pair ?

 

[Dragon Slayer]

They are 5/16" BUT they have to match the retainer you are using. The 5/16" spring retainer come in all different degrees, and that usually is the problem.

 

[70rcode]

Thx D Slayer,.Sure & various Retainer/Lock angle ° spec are adequately listed but the posted issue is Measured v-stem O.D. to advertized v-Lock size functional Compatibility. Just as the importance (or not ?) Of angle ° matching, this topic concerns measured v-Stem O.D. size to v-Stem Lock size design engineered application compatibility. My '69 oem intake & exhaust v-stems mike at .3085" & .3075" (identical to new Manley Int & Exh spec'd valves) respectively & want to use new correctly spec'd Locks. Unlike measurable v-Stems, i Don't kno how to mike v-lock I.D. size & the classic "hang" test works good with only 1 Lock shell holding !! Does Every vendor's advertized 5/16" v-Locks (.3075" thru .311") including non-decimal spec'd 5/16" Locks all work equally good & Unlike the little 2 or 3° Lock Angle ° spec difference Everyone seems to be careful with, does Every 5/16" Locks simply safefy work with .3075" stem valves without concern ? ,...tom

 

[Fran Blacker]

What material is best, chrome-moly , steel or titanium ?

 

[70rcode]

Most would pick the chrome- moly but look at Impulse wrench socket sets....most of the black ones are Chrome-Moly alloy steel that are naturally less brittle & more shatter resistant...i have never use any, but Ti impulse wrench $ockets might be explosively shatterable !

 

[Dragon Slayer]

You might be over thinking this. The Stem Dia is related to your guide inside dia for the clearance you want. Your overall length of stem to your head/spring preload.
I have been involved with several hemi builds including my own, under supervision of a master builder who owned at the time quite a few records in the 60s with a hemi. The issue of precision matching a lock internal dia to stem dia never came up as a concern. 5/16 to 5/16 and 3/8 to 3/8, but never down to a thousand measurement. You do inspect the lock for damage, imperfections, and do a test fit with the retainer on the stem. Frankly it is not the OD of stem your interested in, it is the OD of the notch that the lock engages in. If that diameter is standardized it doesn't matter if the outside dia of stem is off, other than to the guide.

I had to sort through boxes of retainers and locks organizing them in sizes and angles. It becomes pretty obvious what is correct and what is not if your putting retainers and locks on the stem. The will just sink down too low, or not fit at all.

 

[INTMD8]

I had some problems finding bead locks that would work with the Ferrea valves I bought.

Ended up having to send the exhaust valves back to have the lock grooves machined deeper as the lock grooves would bottom out.

Also had a set that were supposed to be 5/16 but no matter how hard you pulled up on the assembly it would just fall apart. (like lock ID was too big).

After 3-4 sets of locks/retainers and having the valves machined I finally have an assembly that locks onto the valve like a collet (Xceldyne ti locks and retainers)

 

[70rcode]

When Chrysler's g2 Hemi valve stems Never meas'd .3125" (the real 5/16"), why should aftermarket brand "X" 5/16" version valve lock be Expected to correctly fit brand "F" 5/16" version valve stem ? For such small, fractional inch, precision fitting Critical parts,...maybe cross-vendor specing to nearest 1/16" (.060") ain't close enough to prevent misfitting surprise !

 

[INTMD8]

Yes, I would have bought locks/retainers from Ferrea to match the valves if they made some that fit my valve springs.