sic7camaro

iTrader: (21)

Hey all im doing a carb swap and was just wondering if im gonna have ptv clearance issue using raptr camshaft 236/242 615./615. 111lsa.the motor is a lq4 with milled heads .30.any help would be appreciated.also anyone know where i can get the ls3 vic jr intake for cheap and what size carb i need i was thinking a 850 dp .what u guys think?.

Prorac1

iTrader: (4)

The cheapest price I have found on an LS3 Victor intake is from the Ebay dealers. Around $300 shipped. And IMHO that cam might be close. The only way to tell is to get some clay and check it, or bring it to a machine shop and have them do it. Eric L

InsaneDomestics

iTrader: (28)

Any other input on this?

JustinCody

Curious what your outcome was on this. I'm going with the exact same setup.

The stunningman

iTrader: (47)

That cam won't properly clear in my experience. You have to many variables working against you. You have milled .030 from the heads. The 111 LSA makes valve clearance problem worse usually. To much duration both intake and exhaust for the stock dish with no valve relief. The intake will probably clear better than the exhaust if either clear at all . You need .080 intake .100 exhaust clearance. People have run tighter but there's no room for error. You over-rev or valve float, you bend some valves or break stuff.

victor3ranger

Bring this back to the top, hoping to get more input.

I am going to be running the same setup except the cam will be different.

Who has a flycutting tool for the guys who want to flycut the piston while it is still in the block??

streetknight2

iTrader: (10)

Subscribed....I'm in same boat

89gmcs15

iTrader: (7)

just a fyi im doing the same build (for the most part) i have a 2004 lq4 block and crank with ls2 pistons and rods fly cut .080 ls3 heads (unmilled) and my cam is a custom grind (234/250 .621/.628 112+4) with my flat top pistons cut flycut .080 i had .116/.118 clearance. now i know cams differ and all but that gives ya a good idea of a setup and what i had.. but id always measure and double check tho...

89gmcs15

iTrader: (7)

and the dish on the lq4 piston will help but not totally fix the situation because the intake valve is so big on the l92/ls3 heads the flycut area was almost off the side of the piston. so it would hit the raised edge of the lq4 piston too

GC99TA

iTrader: (30)

I have an LY6, which for those who may not be familiar with them, it is a dish piston 6 liter with L92 heads from the factory. The main difference between this shortblock and that of an LQ4 is that the LY6 pistons have an exhaust valve relief from the factory and the LQ4 had no valve reliefs. Yes, there are more differences, but the pistons are what counts here.

So having said that, my 231/239-110LSA +1 cam was extremely close on the intake side and my heads and head gaskets are completely stock. I did end up with .090 on the intake, but the cam is installed on a 111 centerline (-1) rather than a 109 as spec'd (+1). I didn't do this on purpose......that's just where the cam ended up with my factory timing set. But, if I chose to advance it two degrees to a 109 where it was intended to be installed, my intake clearance would only get tighter and would surely exceed .080. Conversly the exhaust side, which already has more than enough clearance, would only get looser.

Please take this as reference only. As was already stated, every cam is going to be different and clearance needs to be verified in each combo. Bottom line is......as small as my cam "appears" to be, if it had gone in on a 109 as intended, it wouldn't have cleared with acceptable tolerance.