Valve Lash w/Aluminum heads

[451Mopar]

I just finished setting my Valve lash tighter than normal to see if it will work, but wanted to ask what others run for valve lash.

My engine is the 451 cid (400 block + 440 crank) with Aluminum Brodix B1 B/S heads and aluminum 1.6:1 roller rockers. The cam is an Ultradyne 284R4 roller with 251 duration @ 0.050" and a theoretical 0.620" lift with the 1.6:1 rockers. The pushrods were cut-to-length ones fron Koffels place.

My valve lash settings are now set to (with a cold engine):
Intake = 0.016"
Exhaust= 0.018"

Do you think this is too tight?
It seemed that my lash may be getting looser as the heads heat up?

[JERICOGTX]

what does the cam card call for lash when HOT. Then you should set them about .004 tighter for a starting point.

[AZMOPAR]

I ran B1/BS heads and now Indy 440-1. I found that 0.010 less than cam spec is approximatly correct. One way to find out is to gap them 0.010 less than spec and then run the engine up to temp. Pull a valve cover and check the gap. You now can figure a real number for your combination. I run 0.016/0.018 on my roller that has a mfg spec of 0.026/0.028.

[J-BODY]

I think you are on the right track, but by all means run the engine till hot, and pull the covers and check them agains.

[JANDJ]

SET THEM COLD FOR FIRST START UP -.006 TO -.007 OF THE CAM CARD THEN RESET HOT!

[451Mopar]

Well the lash must be OK.
I drive the 20+ miles to the track today, first run was a 12.561 @ 108.73 MPH
60' was 1.841
1/8 was 8.033 @ 86.82 MPH

And that was through the new 3" TTI exhaust system
The car seems to be running just as strong with the 3" TTI system as when I had the 3.5" with Dynomax welded race mufflers, but the TTI system is much quieter.

All the runs (two time trials and 3 elminations) were pretty consistent. I red lit on the last run
The last run was a 12.592 @ 109.48 MPH

I then drove the 20+ miles home with no problems.