Looking for community input about power adders on auto trans

[Lord Umoja]

So as you guys probably know, I have an S13 Convertible. Since the car is saddled with a 114k mile engine and an autotragic transmission, it would be kind to call the car a dog. Even my wife, who isn't a speed freak, thinks the car is too slow. Almost dangerously slow. So....

Looking for thoughts on how to liven the car up a little bit. My main issue is that the car MUST remain automatic. My wife is handicapped and cannot drive manual.

My goal is roughly 250whp. Maybe a little less but certainly no more than 300. I'm not looking for a drag racing bruiser but after living with a 2004 Mustang Mach 1, I know the value of some reserve power for "oh s***" situations.

I have a partial turbo setup from a previous stalled project and it includes a log manifold and an AGP T3/T04E 50 trim with a 0.63 A/R turbo. I'm fairly sure this is going to be way over kill though.

So I see three options and I want y'alls opinions on which to go. Trans will be figured out no matter what I expect.

Option 1) Go with the current turbo and complete the kit, build a new motor and drop that in.
Advantage: High power
Disadvantage: Unsure if I can source an auto trans to handle the power.

Option 2) Sell off the turbo and manifold and hunt down a GT28RS or something similar (I've seen the GT2871 and GT2860 listed too) and install that on the stock motor until she blows then build something stronger that will survive.
Advantage: Closer to my power goals, may be easier to find a fitting trans.
Disadvantage: Starting the turbo work from scratch. Unfamiliar with the GT28 sized turbos.

Option 3) Nitrous kit on existing motor until it blows.
Advantage: Possibly simplier. Only active when pedal is floored. Can be turned off.
Disadvantage: Bottle needs re-filled. Bottle should be removed from car on hot days. It's nitrous, I don't really trust it.

So all this is preliminary but I wanted the thoughts of people here. I have been given the go-ahead from my wife to do SOMETHING to the car to increase the acceleration as long as it isn't an insane amount of power.

Thanks for all your help everyone.

[float_6969]

What's your budget?

[Lord Umoja]

I'd put the budget at roughly 2-3k

[PapaSmurf2k3]

I'd slap a GT2860 or GT2871 on there, no intercooler, blow through MAF, simple blow off valve (vent to atmosphere), 6 or 7 psi, premium fuel only, ~6:1 rising rate fuel pressure regulator, maybe some slightly larger injectors (370cc) call it a day.

A member on here by username "Geo" used to have a boosted KA with an automatic. Maybe search for posts by him to see if he did anything with the trans.

[Hijacker]

I'm not too hip on KAs and slush boxes (I've literally driven one in the 15 years I've been dealing with the S-chassis, and I ripped it out of the car to drop an RB20 with 5 speed in it post haste), but are there any companies that make adapter plates for any RWD auto transmissions more common to late 90s American cars? Might be an idea if transmission reliability is in question. I only mention late 90s, as once you get past the turn of the century, electronics issues really start to become a larger headache.

[float_6969]

I'd slap a GT2860 or GT2871 on there, no intercooler, blow through MAF, simple blow off valve (vent to atmosphere), 6 or 7 psi, premium fuel only, ~6:1 rising rate fuel pressure regulator, maybe some slightly larger injectors (370cc) call it a day.

A member on here by username "Geo" used to have a boosted KA with an automatic. Maybe search for posts by him to see if he did anything with the trans.

Pretty much this. Will be right about your price range.

[Lord Umoja]

So I have to ask, why the no intercooler? Is it just a cost deal? Or is there another reason to it?

[float_6969]

It's generally accepted that at low boost levels (7psi and below) an intercooler isn't really necessary unless the turbo is somewhat undersized, and the suggested turbo's are a good fit. At low boost levels, the turbo just doesn't heat the air enough to warrant an intercooler. It's also generally accepted that chemical intercooling (water injection) works very well at low boost levels if you're having detonation issues. Also, adding an intercooler increases charge plumbing volume, which decreases throttle response. Ideally, you'd never need an intercooler because the turbo was so efficient that it didn't heat the air at all and the only heat would be due to compression. But that's basically impossible, so once the boost starts climbing, so does turbo outlet temp.

[PapaSmurf2k3]

^Exactly.
Having no intercooler cuts down on cost, install time, and increases reliability. The less couplers and connections and stuff you have, the better off you are.
Also, I updated the thread title to better reflect the content of the thread for future search purposes.

[Lord Umoja]

Float and PapaSmurf,

Thank you both for the answers and help. I had worked on reading up on turbo systems with my previous project but that was a high boost application so I went directly to an intercooler.

I'm currently reading through 2 turbocharging books now that I'll post the cover photos to. I'm lucky that one of them has the compressor maps for the GT2860RS and the GT2871 in it so I can figure out which one I should fit to the car.

I've also started reading through GEOs posts but there are sooo many of them to sort through. I'm also working to find bell housing schematics for the various automatic transmissions offered by Nissan to see if anything is interchangeable on the KA.

[Lord Umoja]

So this is the first book I'm using. Going by the formula inside and the compressor maps, the GT2860RS is the best choice, although that may be overly large for such low boost levels. But hey, room to grow.

[WDRacing]

I'd run an intercooler on everything. They're cheap AF and unless you're a total retard you can plumb one in reliably. If I wasn't running an intercooler I'd run a single stage water injection system. Detonation kills more motors than literally anything else aside from maybe total neglect.

The FMU/blow-thru MAF/BOV for low boost is definitely the best bang buck option. Without an intercooler/water injection I'd retard the base timing a couple of degrees as a daily driver safety measure.

If the auto stays give her a good fluid exchange and add a nice trans cooler BEFORE you add boost. Heat kills the automatic trans. The larger turbo will be laggy but that added lag will actually assist in the longevity of the transmission.

If it were my car I'd go with a T28ish sized turbo. Something small with little to no lag so you can build full boost while holding the foot brake. FMU/blow-thru MAF/BOV/FMIC intercooler/single stage water injection system/dual stg boost controller/large trans cooler plus temp gauge. Spare automatic trans. Go!

WD

[PapaSmurf2k3]

If you know your way around a compressor map, you should check out this article:
so-i-made-you-guys-some-compressor-map- ... 29705.html

I'll try to fix those dead picture links at some point, but the spreadsheets are hosted by NICO, so they should still work.