Hey Guys,

I posted this in my build thread over in Advanced Performance, but I figured I would post here as well since it will get more traffic for you LSJ guys.

Went to assemble my LSJ head this weekend with my Supertech 78lb valve spring kit, and this was the outcome...




They don't clear the head casting. If you look closely, directly infront of the lash adjuster the spring is contacting the head casting.

Upon further inspection, it would seem it is hit or miss for the rest of the valves, some of the springs clear the head casting and some don't. The Supertech springs are slightly larger in diameter than the stock springs, however even the stock springs I noticed are very close to contacting the head casting. Doesn't leave much room for spring deformation when compressed.

It should also be noted the exhaust valve spring "pockets" have had material removed from GM to allow the springs to clear...however a few again would not clear the Supertech springs.

I have never heard of this issue before with running Supertechs in an LSJ head, I am wondering if anyone has run into this issue in the past??

This could help explain why people were having their Supertech springs fail....not sure what the exact details of these failures have been tho, just that people have had failures, so maybe they are unrealated.

This is not really a big issue for me, since my head is not mounted to the block yet I am just going to die grind some material away on the head so that they do clear, but I figured I'd let you guys know.

Hope this helps someone out/hopefully someone can help shed some light on this issue if they have incountered it in the past.





PS. Yes, before posting this I did realize this thread will be filled with unintelligent replies such as, "ZZP valve springs FTW", I decided to post it anyways.

 

This is the same case with the lnf head. I had to notch out quite a bit on mine. I cant believe so many people put these springs in and never caught it lol. Here is what mine looked like before hand, you can clearly see it. however, the ZZP springs do fit with no issues lol. I still went with the supertechs tho.

 

I can believe people put motors together without catching that. Seems very obvious to people that have experience building motors but people that dont, i've seen some crazy stuff slapped together.

Good catch by both posters though. Never have built a LSJ but i'd like to get a spare one to start on.

 

i had to notch areas around each spring on the exhaust side of my cylinder head for my supertechs

 

also just to make sure... the ring sleeve goes around the valve seal and the retainer of course goes on top like you have.. ask me how i know lol

 

Hmm I figured I wouldn't be the only person with issues (unless I had some weird casting), strange there is no info out there about this tho.

Regardless, good info for anyone looking to upgrade their valve springs in their LSJ.

 

what are you refring to as a ring sleeve

 

I assume he is refering to the inner valve spring seat, the 78lb kit comes with seats for the inner spring to lift them up so that they clear the valve seal.

 

the spring bucket then