LQ9 Camshaft Install Problems

[Chevelle LT1]

I could really use a second, third, or umpteenth opinion on this:



I am trying to install a new camshaft on my LQ9. The block is an 03MY, with Corvette LS3 heads and intake. The cam is a Texas Speed & Performance cam, intended for the LS3, but "should" be OK for my LQ9 block. The problem I am running into, and corroborated by the photo, is that the end of the cam is clearly different than what I just removed from the block:
1) On the end of the cam, there are no provisions for bolting in the timing chain gear (at least like the LQ9). The LQ9 cam has three bolt holes on the perimeter, with the dowel pin for locating the gear. The new cam only has a threaded hole in the center of the cam, and a smaller-diameter dowel pin.
2) The "snout" on the end of the cam seems to be a different length. Overall, the cam lobes match up identically, but where the timing chain gear mounts this is a different length (or height as shown in the photo)

Did I get the wrong cam, or is this just part of the change-over required for using the LS3 cam? (i.e., I need to buy a new gear?) Unfortunately, Texas S&P isn't open today, so I appreciate any feedback anyone else can give me. Thanks!

~ Jason

[MrForce]

There are 3 bolt and one bolt LSx cams. Three bolts are older (LS1 and truck) style. You probably need a later model timing chain set and possibly a cover swap. Swapping the cam for the same grind in 3 bolt is probably the best option if still available. LS1tech.com has a fair amount of info on this.


HTH,

Rob

[Chevelle LT1]

Rob -

That's a huge help...thanks for the response. I'll check LS1tech, also.

~ Jason

[camcojb]

make sure you check valve to piston clearance on those LQ9's. I'm fighting that now with mine with LS3 heads. My Texas Speed LS3 heads have 64cc chambers, and that reduced the valve drop, and so I am now trying some stock un-cut LS3 heads.

All I'm saying is to take the time on yours to verify that the cam you're using will have enough clearance. Mine cleared but nowhere near enough clearance to run, and would have broken pistons and/or bent valves if I had decided not to check it and assume it would work............

Jody

[Chevelle LT1]

Jody -

Thanks, will do. This is a new endeavor for me, so I appreciate the advice. Did you have to fly-cut the pistons to make it work?

~ Jason

[camcojb]

Jody -

Thanks, will do. This is a new endeavor for me, so I appreciate the advice. Did you have to fly-cut the pistons to make it work?

~ Jason

that's what I'm attempting to avoid. The LQ9's are flat tops, no valve reliefs, plus they go .006-.007" out of the deck. If I have to cut the pistons I'd probably do a complete short block. I'm hoping to avoid that, waiting on the stock heads to show up next week.

Jody