Questions from a NOOB

[Ridin_Sidewayz]

Hey all, Iam new to the tuner scene and have recently purchased a 1996 S14 for my first project. I have been lurking these forums for a few weeks now and have come up a few generic questions. I come from a long background of American Muscle (F-bodies and one highly modified S-10 3.4 swap) so forced induction hs never been a consideration for me unless it was belt driven. I am feeling a little lost on some of the basics.

Turbo size - I get the whole T25, T03, hybrid designations, but what are the A/R and housing numbers I keep seeing?

Stock Power handling ability - All my F-body friends are giving me hell for going rice, I want boost and I want it now. How much power can the stock AT stand up to? My goals are 325-350 RWHP. This forums describes rods, pistons etc, but nothing about AT (a 5 speed swap is planned for the future but not soon so don't even think of telling me to just swap the transmission. I want technical advice,not biased opinions)

Streetability - I have a spare KA-24DE and will be rebuilding it from the bottom up (when it goes in it will have the manual trans with it) What is a good approximation of how much power I can squeeze out of this engine and still drive it daily? I have heard 325 is about the best compromise but I would really like to see about 425 plus a bottle of Nitrous just for kicks.Engine build will consist of the following if it's relevant:Cryroed and micropolished crankCrower RodsWiseco Forged Pistons .020 overported and polished headwith 3 angle valve job and better springs/retainers

Thanks for the input

[Chezedik]

Hey all, Iam new to the tuner scene and have recently purchased a 1996 S14 for my first project. I have been lurking these forums for a few weeks now and have come up a few generic questions. I come from a long background of American Muscle (F-bodies and one highly modified S-10 3.4 swap) so forced induction hs never been a consideration for me unless it was belt driven. I am feeling a little lost on some of the basics.

Turbo size - I get the whole T25, T03, hybrid designations, but what are the A/R and housing numbers I keep seeing?

Stock Power handling ability - All my F-body friends are giving me hell for going rice, I want boost and I want it now. How much power can the stock AT stand up to? My goals are 325-350 RWHP. This forums describes rods, pistons etc, but nothing about AT (a 5 speed swap is planned for the future but not soon so don't even think of telling me to just swap the transmission. I want technical advice,not biased opinions)

Streetability - I have a spare KA-24DE and will be rebuilding it from the bottom up (when it goes in it will have the manual trans with it) What is a good approximation of how much power I can squeeze out of this engine and still drive it daily? I have heard 325 is about the best compromise but I would really like to see about 425 plus a bottle of Nitrous just for kicks.Engine build will consist of the following if it's relevant:Cryroed and micropolished crankCrower RodsWiseco Forged Pistons .020 overported and polished headwith 3 angle valve job and better springs/retainers

Thanks for the input

Let me preface this by saying if you hadn't said that this was your first pattie hopper I would tell you to search. Also, you mentioned that you didn't. And while the info you are looking for can be found online, I will help.

A/R is the ratio of major diameter and minor diameter of a wheel. What that means is that a wheel on a turbo has two sizes on it. For instance, on the compressor, where is inducts is the minor diameter, and the output (animal end of the snail) is the major diameter. If you ever rebuild one, you will understand a lot better.

Basically, if you have a major dia. of 1 in and a minor dia of .5, then the A/R will be 1/.5=2.

So what does this mean to you? Well, on the turbine side, the lower the number, the lower the boost threshold (faster spool), on the compressor side it generally tells placement of the islands in a map. Trim affects the shape of the islands. Trim is NOT the same as A/R. Trim is the physical shape of the blades, whereas A/R just tells you a particular ratio.

Learn to read a turbo map, and you can make some good choices. If you do not want to (and are loaded), you could just pick a T3/T04e .50 or a GT35r. But if you want to do it right, you can learn a lot, and save some cash. Problem is, it will take time.

EDIT: on your setup, forget about the crank it is good 'til well beyond 700hp. Also, the springs and such in the head are fine. Worry about compression, and forged internals, and cams. Then find a very efficient turbo. Manage the hell out of it, and that's how you make power.

KEEP READING!!! Welcome to NICO!

[GlacierFreeze]

Not to take away from NICO but KA-T.org is a good source too.

[Ridin_Sidewayz]

Thanks, I found a tutorial somewhere on one of the forums which teaches you how to read a turbo map.I will pay it some closer attention.

Glacier, I'm hangin on KA-T also :-)