Hi from the UK.

I have purchased a brand new unused, but second hand crate LS3. Part number 12650777. I believe this is for an automatic car, but I will be using it on a manual box. I'm prepping it to go into a Porsche 996. I have changed the cam, timing chain damper and valve springs to the ASA spec 525hp, and the sump to a corvette item. I have also purchased a GM run kit complete. I am really struggling with the pollution control system and steam lines. I have not got a clue how to plumb them all. Pictures below. I would like the system to remain stock if possible, and would rather not run a catch tank if possible. Any help most welcome.

2nd question: I have an ATI harmonic balancer/damper - bit it only has the pulley for one belt - As I will be running the GM alternator and AC compressor I need two belt pulleys - is it possible to change part of the dampner to a twin set up or will I need a whole new unit?

Just a general comment being here in the UK: You US guys are soooo lucky - your tuning parts as soooo cheap compared to the UK. It's really frustrating if we buy your parts and ship them over. Shipping, import duty and VAT makes it a very expensive deal! Count yourselfs lucky!

 

I think they sell the ati pulley on Ebay.

 

I don't have a definitive answer for your 2nd question but I just finished doing an LS swap into my Miata and the front pulley is dependent on which front accessory drive you will be using. Different balancer pulleys are used because various accessory drives stick out closer or further from the front of the block and different quantity of belts are utilized.
For my swap (and I suspect for yours) I utilized the GM Performance front accessory drive kit that uses parts originally utilized on the 2004 to 2007 Cadillac CTS-V because it puts all the accessories and the belts nice and close to the engine. However, because my engine is not supercharged I could not utilize the Cadillac 3 belt balancer. I had to utilize the 2004 Corvette 2 belt balancer and water pump because it puts the belts at the correct distance from the block.

Again, your application might be different.

 

My LS3 crate motor came new with a Corvette-spacing pulley with grooves for the A/C compressor (closest to block) and the main serpentine that drives everything else. Suspect that's what you'll need.

As for connections -- in the order of your pictures somewhat -- 1) the little red cap on the line that sticks forward on US driver's side of the throttle body is the steam line --- just plumb that into whatever hose connects your coolant reservoir to your radiator lines. Pic below of how mine ties into my reservoir. Realize your rads are up front..... 2) The little line coming off the US passenger side valve cover -- that is your positive crankcase ventilation (PCV) make up air line. It should be plumbed into your air intake tube DOWNSTREAM of the MAF sensor -- this way all combustion air entering the intake manifold, including that from the PCV system is metered. 3) The little "u-turn" tube on the US passenger side behind the throttle body is the PCV connection -- connects the lifter valley (crankcase) to the manifold. 4) The red capped fitting on the back of the intake is simply manifold vacuum -- I used it to connect to my brake booster and my vacuum/fuel economy gauge. 5) The little square shaped box that connects via plastic tubing to the throttle body area is the purge valve for the fuel system -- the outlet of your charcoal canister gets connected to that nipple. If your GM ECU is working correctly, the factory harness plugs into that also and from time to time it pulls fumes from the fuel system/charcoal canister into the engine to be combusted. If you end up having that feature shut off by a tune -- then simply connect your charcoal canister to your air inlet tube UPSTREAM of the MAF sensor.

Pic below -- you can see the coolant reservoir connecting to the top of the radiator on the US driver's side -- see the "T" fitting? The other end of the hose at the T connects to the red capped steam fitting sticking out of the US driver's side head.



I installed two threaded fittings in my engine air inlet tube and screwed in two barbed fittings --- one for the hose going to the PCV make up air nipple, and one for my connection to my charcoal canister. In the pic below you can see the fitting with hose going to the PCV make up air nipple - the hose runs over the top of the throttle body motor. The nipple for the charcoal canister comes into the bottom of the air inlet tube.




Because my purge valve function was turned off in my ECU tune, I simply capped the nipple where the purge valve connects as in the pic below.



Here's what the low mount A/C compressor (Alan Groves brand) and the low mount alt bracket (ICT Billet) looks like, also Caddy CTV-S Power steering pump/bracket.



Hope that helps!

 

unclemark - you get things figured out?

 

Michael, yes all understood. Thank you for your detailed response. Mark.