LS9 Cam -
 

Well I finally blew the engine after 100000 miles of 15 lbs boost everyday for 6 years and have ordered an LS9 cam for a new engine build. Does anyone know if the LQ4 Blocks have the provisions for the timing chain damper and do I need one? Your help would be much appreciated.

:bang:

As to your question, I am not sure. What let go on your motor?

I'm impressed it lasted so long with that much boost.

As for the cam, isnt that better suited to rectangular ports with boost? Most custom cams I see for cathedral port heads dont have quite that much split.

That actually a good split for boost but it wouldn't be my first choice do to the 122.5 LSA

What size motor is going back in?

The lifters got pooched and looking back now it made sense. I put in the Com 918 springs which increased the load by at least 50lbs at full valve opening and I should have also changed the lifters to the comp cam ones. Eventually all the lifters collapsed and I found needle bearings in the oil. Had the lifters held up there is no doubt in my mind that I could have gotten 150000 miles.

I am picking up a new LQ4 tomorrow and retrofitting the motor with the LS9 cam and LS9springs. I considered the LPE GT9 cam which will need comp springs for sure but elected for some fuel economy since it is a daily driver. The dyno chart on the LS9 seems to pull very hard past 6600. The LSA should allow me to idle at 500.

Im also considering a powerbond pulley to get some extra boost while the motor is out.

:chug:

Also I found out the LQ4 blocks do not have the provision for the chain dampener. I will be relocating the cam sensor to the front cover so we'll have to see how that pans out.

Lpe has a cam sensor relocation kit. Lq4 blocks have untapped bosses but the chain dampener for the ls1 is different than ls2. I was going to run the ls9 cam but have changed direction. I'll be interested to see your results.

Yeah, I really should be porting the heads while the engine is on a stand - that should really wake up the engine up top.

If your going with the LS9 cam on a 6.0, why not just go with the L92's and have the rec ports? I would think That would flow as well as getting the stockers ported....

John

...and the cam was desinged with the low intake/exhaust flow ratio of the L92's. Rectangular port cams have a ton more seperation between in/ex duration.

Rick