I am brand new to the LS world and I have purchased a 5.3 with 243 heads and BTR stage 2 cam. Head studs, bearings, forged assembly, blah blah the short block and valve train are definitely sufficient. Although I’m curious will the 243 stock rocker arms with trunions suffice? This setup came with a new sniper 1250hp efi unit and ls msd black box. Through my recent research I’ve concluded finding a standalone system for engine management may be better or more capable for upping the power in the future as a sniper is rated for 14psi boost. I’m

 

Those heads and rockers are fine for most. What are your power goals?

 

I’d like to have a 9 second street car. I figured maybe 650-700whp would get me there easy in a 3500lbs car

 

**For those following, I wasn’t able to finish my writing. ** My intentions with the build are to build a serious street car and try it out in the track a few times* I’m figuring this will require some sort of progressive boost control, simplest method? This car I would estimate at 3500lbs I plan to run a th400 and a 3.42 rear gear. The turbo I received in this setup is a twin scroll t6 s475 I believe you would refer to as a 96mm with a 1.32 ar. Is this too much turbo? Can a simple Borg Warner as such handle 2 step on launch? With small diameter pipes off the collectors to a split flange and the right converter I infer I would be able to spool this on the street. What I’m looking for is cheap and simple ecu advice I’m open to doing away with the sniper setup and standalone ignition control. Also I’m concerned about the turbo size and functionality for this application. Any advice or fact based opinions are appreciated. Thanks in advanced.

 

Start reading the builds threads. There is a ton of LS builds. Many use that same turbo. I myself built a very similar combo. It went 9.90 first time out.

 

Thanks. Would love to see your setup and specs.

 

Like Disney said, that turbo is used on many builds here, plenty of them 5.3's. What exactly are you looking for when you say spool on the street? It's not going to be making big boost numbers at 2500, but with the right converter (and or transbrake), and a little 2 step it'll do quite well. The genuine BW s475 is a very robust turbo, one of it's original applications was a 14 liter diesel. There are China versions out there though. X2 on the builds board, you'll find plenty of relatable info.

 

Also, depending on what you're looking for as far as options, the Holley Terminator X is tough to beat price wise in a plug and play ecu.

 

https://www.theturboforums.com/threads/lx-coupe-ls-heart-first-turby-ls-build.368736/

 

My car will be driven regularly on the street and I want to make sure that won’t be an issue with performance and reliability. It is a real deal Borg Warner brand new in the box. I may not get the 2 step set up immediately I have no transbrake at the moment someday probably but I just want to assures I’ll have no issues with getting the turbo up and going. I hope to go with a ptc converter and I hope they can get the setup working slick. I’ve also heard and been concerned that a stock, base s475 that it can’t handle 2 step well. Is this true if a guy used it strictly/regularly for launches? I’ll do some research on that ecu setup as well. Thanks guys I appreciate the info immensely.

 

I guess I haven't seen or heard that about the BW's. From my experience, I wouldn't sweat it, but i'm not one of those who sits on the two step just to look cool.

 

i had a s475, it is the hand me down turbo, so far it has been on 4 cars. the following weights are race weight.
408 sbf, #3500 9.72 @150 too small for the engine
6.0 ls #3600 9.6 @155
5.3ls junkyard stock gen 4 #3700 9.4 @155 -good match daily driven for about 15,000 miles
6.0ls #3100 9.1@160

its been in service for 7 years and on the 2step for at least an hour

 

Good fuckin deal ! Out of curiosity was it a t4or t6 housing

 

this is the 6t you have. i have to take back the age of the thing its origional puchase date is in 2007.
another thing to note is that it will be slow to come up on a 5.3 without a good converter. the above mentioned 5.3 first time out was running low 12's at 10-12 lbs boost on a stock 4l80 and converter. a simple converter change and it was going mid 10's with everything else the same