turbo sizing

[upatnight]

what is the formula used to find the right turbo? I'm looking to upgrade and want to get the biggest bang for my limited bucks.

[toplessFC3Sman]

Its a bit harder than just a formula; you should read up on some of the sticky threads in "Single Turbo" section of the 7 club, and Garrett has a basic explanation of turbo tech & maps too (You are not allowed to view links. Register or Login), although its still just the tip of the iceberg.

Ultimately, your budget is going to be the constraining factor, so how many clams are we looking at?  You're going to need to factor in injectors, and engine control regardless, with exh. manifold, downpipe & all the oil & cooling connections (and IC & tubing likely) for something that does not match the stock turbo's connections (basically anything besides a stock-hybrid turbo like a BNR)

[ITSWILL]

Pick up a copy of "maximum boost" by corky bell.  It's an excellent read. I would recommend reading if entirely before you buy anything.

[upatnight]

i like the corky bell books, and the cheeseball in me would say that knowledge is horse power, at least in this case. as far as clams go, I'm looking at $700-$1000. i have a line on garret anything for cheap. i was looking at a gt35r for about $1100 and change. then i started to research the to4s, oil cooled only, p trim with a .96 hot side t4 with the divided housing, and serge ports on the cold side for around $700. i don't like the idea of oil cooled only. I'm pretty sure garret parts are mostly interchangeable and should be able to find a water and oil cooled center. i already have a front mount so miner adjustments would have to be made there. as exhaust manifolds go i have three friends that weld for a living and have built some of the finest custom manifolds i have ever seen. I'm currently working a mega squirt and my buddy works at kinsler fuel injection and just needs to know what size injectors i need. i was thinking of running 2 extra injectors but that's still in the day dream phase.   

[toplessFC3Sman]

Sounds like you've got quite the set of connections then.  Last thing would be to figure out how much power you want, and how much lag you're willing to sacrifice.  The GT35's seem to be the most popular as "do everything" type turbo, and eventually I'd like to go to something like a GT3582R (so a slightly smaller turbine) to try to minimize lag a little, and get spooled a little earlier at the expense of top end.  The GT35's with a 1.06 AR turbine seem pretty popular too

[upatnight]

yeah it is time to crunch the numbers and find the sweet spot I'm looking for. money is the defining factor in the equation. i cant wait to feel that kick in the pants that more power will give ya. i had the car out to a few track days (I'm not good) and have been modding this, that, and the other thing as my budget allowed me to. over that period of time i have grown use to the power and most of the people i talk to say, getting away from the stock turbo was the best thing they have done.