87coupe6.0

Hey everyone.i building a lq9 and my current cam is a tsp 624 614 233 239 with 111 lobe seperation with 823 heads and .040 compressed cometic head gaskets.with this combo have any ptv clearance issues? Also what kind of power can I expect from this combination?

tech@WS6store

iTrader: (2)

Youre gonna be VERY close. Depends on the icl.of your cam but if its 109 or less youll want to double check.

87coupe6.0

Well my 40 compressed hadn't came in yet so had them switch to the standard .051.cam is a 110 icl

tech@WS6store

iTrader: (2)

That will help but youre still pretty close. Definitely want to make sure on your pr length as well. A 231 would give you quite a bit more clearance but you should be ok.

87coupe6.0

Pushrod length shouldn't change should it?should just be the stock 7.4 right?

tech@WS6store

iTrader: (2)

With a cam that is close on ptv it would be best to double check that.

87coupe6.0

Ok thanks for your reply

A.R. Shale Targa

iTrader: (2)

Are these the L92 big valve castings ??? 2.165" intake valve
IMO that would most likely be too close with either the .040" or the .051" gaskets
Bringing that intake lobe back to 230 or 229 @ .050" would buy you some safety net

tech@WS6store

iTrader: (2)

I have personally seen a 233 used if around a 110 or higher icl with a good margin for ptv.

87coupe6.0

Yeah these are the big valve heads.texas speed seems to think it should have plenty of room.he said the biggest cam they put in a lq9 was 23?-248 duration

tech@WS6store

iTrader: (2)

Every degree after 231 is the point of diminishing returns on ls3 heads on an lq9 piston esp with an early icl.

A.R. Shale Targa

iTrader: (2)

Buddy of mine ran the TSP 231/237 stick in his LS3 however the aluminum block grows or "swells" more than the iron block stuff so at operating temp he did have a few more thousandths but it was still tight....around bare minimum numbers IIRC
Another component in this equation is the sloppiness of the timing chain since the cam can be ground in the right range but if allowed to move around too much can also cause issues.
Guess I'd hate for the OP to even shave his heads a few thou and run into issues.....most would say "hey the junk yards are full of iron block donors" but lets face it, eventually they will be gone......
Not trying to argue with any pros here just hate seeing any "My S#it's F*cked" threads.................

87coupe6.0

Yeah mine is a iron 6.0 block with a new timing chain so I'm hoping for the best lol

tech@WS6store

iTrader: (2)

That is why the pushrod length is important on this setup.

87coupe6.0

Right on thanks

01ssreda4

iTrader: (96)

Check it, that will be close, possibly .100 or less on both sides.

87coupe6.0

Definitely will.appreciate all the replies.

rpturbo

iTrader: (47)

Running a little close on the intake is one thing, but don't tempt that exhaust side too much, remember, thats where the "chase" happens.