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-   -   Valve Lash Caps (https://www.racingjunk.com/forums/showthread.php?t=28266)

Ranchero65 06-15-2010 08:26 AM

Valve Lash Caps
 
Anyone here use them ? Setting up valve geometry on a 302 with Trick Flow TW heads. On the exhaust valve by putting a lash cap on and using a 7.45" push rod I have a perfect mark in middle of cap about .040 wide.
By holding my finger on the cap I can get a .0015 feeler gauge under it . How much clearance do I need ? Is it OK to run like this ? If not OK to run could I grind a little off the caps or do I need to change keepers ? I have never used lash caps before so need help .. Thanks

oldandtired 06-15-2010 08:49 AM

First of all, do not grind the lash caps. They need to be perfect so they will contact the roller tip and transfer the lift to the keepers//retainers.

I always run lash caps if I have a soild roller cam. No matter if you run them or not, the last purchase should be the pushrods.

The following are things that can change your required length:

Head gasket thickness
Block decked
Heads milled
Valve seats too high or ground too low
Base circle on the cam

Good luck, Dave

Tod74 06-15-2010 10:11 PM

I bought some but they did not snap on real tight and I decided to leave em off....Maybe I'm just paranoid but I am afraid they will end up some place I don't want em if a rocker comes loose etc.

oldandtired 06-16-2010 05:42 AM


Originally Posted by Tod74
I bought some but they did not snap on real tight and I decided to leave em off....Maybe I'm just paranoid but I am afraid they will end up some place I don't want em if a rocker comes loose etc.

Good move. It's best to buy a matched set as they do fit rather good. The first ones on the market did not have a hole in them and it was really hard to remove them once they had been run (suction lock). They finally realized to drill a hole to prevent this. Dave

zipper06 06-17-2010 12:46 PM

While we're on the subject, i have always run lash caps also with a solid roller setup. BUT :?: I now have a T&D setup on my new sm/blk engine, i know the T&D's don't move around side to side like the reg. roller rockers do, so you guys running T&D and Jessel shaft still run the lash caps. I do have the lash caps for the heads, and haven't ordered the pushrods yet, because i need to measure for the length when i set the geomerty, No guide plates on these heads and .180 offset intake lifters.

Zip.

gimmemud 06-18-2010 08:05 AM

Zipp, if your valves are not hardened tips the Manton Lash Locks work great.

http://www.competitionproducts.com/M.../NME603431-16/

zipper06 06-18-2010 10:37 AM


Originally Posted by gimmemud
Zipp, if your valves are not hardened tips the Manton Lash Locks work great.

http://www.competitionproducts.com/M.../NME603431-16/

The intakes are 2.140 Tit, and have the hardened tips, the ex are 1.6 stainless, Brodix 10's,RP,FP, i'm thinking i'll set them without lash caps and keep a close eye on them.

Zip.

Ranchero65 07-04-2010 09:00 AM

Just to update:
I ended up using the lash caps on the exhaust side only . I ground enough off the bottoms to have .005 clearence between cap and keepers. I now have things set up using same size push rod for all . If I had not used the lash caps I would have had to use a 7.5 or longer push rod on the exh side and using a longer pushrod I feared rocker stud shearing off as rocker travel was right there against it. this was with Trick Flow TW 170cc heads and Miller rockers with hyd flat lifters.


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