Vanilla Ice

Will these cause any clearance issues on a stock Lb9? I assume valve cover braces will need grinding. But what about bosses and PTV with the added lift?
Assume I have the 350 cam.

I have not seen a definitive answer yet.

Has anybody done it and have a definitive answer about it? I don't want hearsay or propaganda or "get a proper cam."

Vanilla Ice

I guess nobody still around has any info?

Indypacetruck

Hi, I have a similar question and added a new thread under zz4 rocker swap as I want to run this exact rockers on the intake and 1.6 on the exhaust on my zz4!! I was trying to get ahold of kevin91z as he is still an administrator and had an old post back in 2007 regarding his zz4 350 with the stock aluminium l98 heads. He installed 1.65 rockers and I wanted to know what parts he used springs, pushrods/length?? according to many online information I've read, most people used a 7.2 pushrod and cleared with no issue especially with stock self aligning rocker motors as they seem to have a bigger pushrod hole in the heads, but there are also some that say they had to slightly oversize the hole and get different pushrods. This is why i am trying to get KEVIN91Z to respond which would get us the info or ballpark we need. I'll share the info as I aquire it. We could always buy parts and try them and measure but in this day and age that usually costs too much and takes too much time, surely several people have tried it and have the info we need

Vanilla Ice

1.7s on a 350 has been done. This thread is about lb9 heads and bottom end. I want to know about a tpi 305.

Indypacetruck

Sorry I misread, but it's very similar maybe someone can reply and help us both! As far as the lb9 heads I know for a fact that it doesn't flow very well and the added lift probably wouldn't make much of a difference for the $300 spent on rockers! I would bolt a set of slightly used real aluminium l98 zz4 heads which are usually around $400 used with 7.2" magnum pushrods and oe style roller lifters which you should already have. Then just use 1.6 rockers and you'll pickup and easy 70hp+ From the flow and rockers. Just my experience!!

Vanilla Ice

I am not buying heads and the 1.7s are at my disposal. Lb9 heads flow fine for my goals. The added lift may not add flow at peak but will increase flow all over. And with the eventuality of a turbo I want the added flow.

I don't really care to have any other setups discussed in this very specifically titled thread.

If it's not about lift limitation and geometry of the LB9 heads/shortblock please leave it out of this thread.

Indypacetruck

Sorry got carried away with what I've done in the past and thought you might be interested in best power for dollar. But since you already have the rockers at your disposal. May as well put them on. The only thing you will need to get is new beehive springs with retainers,locks and locators. The stock springs WILL NOT take the added lift and way faster ramp of the cam after 1.7rr is installed and you will float and may hit the retainer on the valve seal and cause damage. Install the new springs at 1.8" height and you will have ample clearance. While you are at it I suggest new .80 wall hardened pushrods like the comp magnums because the added ramp speed and lift will add twice the load and flex the stock pushrods and cause valvetrain instability and breakage down the road. Other then that you should be good to go as a 305-350 with stock heads will take around a .550 lift till you need relief cut Pistons and lots of measuring so stay a safe margin below.Hope this helps cheers!!