pdm14269

Planning my lq4 build and my goal is around 800 rwhp with a stock crank, h beam rods, and forged pistons. I am looking at Borg warner s475 to s480. I will be running a 3600-3800 stall with a trans brake and I want something that is capable of making the horsepower I want but I want it to spool up hard when I bring it up on the brake so it launches hard. Originally I was looking at an t6 s475 with 83mm turbine and 1.10 a/r. I picked smaller turbine and a/r so it would spool early. Can I would like to go with is a tick stage 2 and I am gonna run e85 so I am thinking somewhere around 95lb injector. I would appreciate any feedback from people with experience with similar combos. I have done many many hours of research over the last month before posting this and this is the best combo I can come up with for now. Thanks guys.

1CAMWNDR

iTrader: (21)

Never mind. Miscommunication FTMFL.

pdm14269

I guess you read that before I edited it.

1CAMWNDR

iTrader: (21)

Yeah, when it is a first post and the only thing there is a joker smiley and Matt in bold letters it looks like a troll.

1CAMWNDR

iTrader: (21)

I would think a T4 1.25 S476 with a 87mm turbine would both spool pretty quick and have excellent flow out the high end.

NoorJ

I was just going to suggest that, you don't need the 476 though if you want to keep costs down stay with s475 but go T4 and the 87mm turbine ind

1CAMWNDR

iTrader: (21)

Yep. Would probably work both ways. I was just going to suggest the middle of the S475-S480 range for some room to grow. Maybe add a Race cover if funds allow.

pdm14269

Turbos I am looking at are on forcedinductions.com and for price I would like to stay under $1000. Reason why I wanted to go t6 is for better top end flow and I can run 2 1/2" feed tubes from my manifolds to the flange. I figured the big footprint would allow for a nice non restrictive transition into the turbo. I think 480 might be too big and 475 a tad small for future plans. Maybe 476 or 478. Just not sure on turbine size and a/r.

pdm14269

Anybody else have any advice or experience with a similar setup.

RedRocketZ28

iTrader: (19)

I ran 2 1/4" piping into my T6 S480 92mm 1.10 a/r on my SBE LQ4 in my old Camaro. It made 727 rwhp on 16-17 lbs. It had no issues spooling except for on the footbrake. A 2-step helped that out though. You will be fine with a t-brake.

I just placed an order for my new turbo which is a T6 S480 96mm 1.32 a/r with a billet wheel. I will again be using a SBE LQ4 in my new car. Will aslo be going with 2 1/4" piping again. My old car had an early year motor so didn't want to push it too hard, but the new one is an 05+ so I will throw more at it. A box stock S480 would do what you want for sure and leave you with room to grow later on down the road.

pdm14269

What is your reasoning for going with the larger turbine and a/r. Was it running out on top end? Were you on gas or ethanol? It seems like a lot of people are running 2 1/4" turbo feed tubes. I'm just curios why not 2 1/2".

Forcefed86

iTrader: (4)

Because larger tubing size only slows velocity/spool time. 2.5" is too large for an 800hp goal on your setup. 2.25" or even 2" would perform better IMO. And the larger 96mm s475 would be much better suited than the 83mm wheel.

LJMSJohn

Your Thought process is flawed... smaller turbine wheel and housing does NOT automatically mean quicker spool... with a converter that loose... you will have no issue getting from launch boost to targeted max boost in under a second even with a 96/1.32 hotside. Casey Rance at SWG performance just swapped over to a billet 84mm with a 96/1.32 from a billet 80 with a 92/1.25 ( iirc) and the 96/1.32 spools quicker than the smaller turbine did.

plus the 83mm turbine doesnt really have the capacity to support a cast 80mm wheel completely... i Advise against putting that turbo together like that.

pdm14269

OK I like all the input. I was thinking that the smaller turbine would increase velocity therefore increasing spool time. Sounds like your telling me that the small turbine would have more restriction and hurt spool along with top end flow. Is that the case in this situation? I am used to the diesel theory about turbine size and and flow but that is all low rpm.

forcd ind

iTrader: (7)

If using E85, I would have someone with exp. ck your injector sizing, you may need bigger depending on final power

pdm14269

Thank you.

tblentrprz

95lb (rated at 43.5psi) with base pressure increased to 60psi @ 80dc will get you to 800rwhp.

Might consider 105s or even 120s to give you more opportunity down the road.

pdm14269

Any help is greatly appreciated. My father passed away 5 weeks ago and he was a machanic and drag raced for most of his life. The last couple years he has been pushing me to get my car back together but he was very old school. I am selling of my old small block stuff to fund this build and I just want to do it the right way and make him proud. I put this off long enough and I am motivated with all my heart to make this dream a reality so I greatly appreciate any input or advice that anybody has to offer.

93camaro_zzz

iTrader: (13)

John, sent you a PM as to not clutter up this thread.