Turbos

How in the hell can i find any info on turbos for the 93 LS? all you people do is tell me to search the forums and ****. please give me some real websites that actually have a turbo kit for the 6. also, i cant get to the tkt site. give me some help please.

[mts3]

This too will likely get closed. Basically TKT or custom are the only ways to go. Seems there is more than one URL for TKT though. Maybe you didn' t look hard enough?

[Ruubstr94Ls]

He didn't. Do some searching for turbo or turbochargers. Theres plenty of information especially on www.probetalk.com

[Mike 94PGT]

I don't know what to do with all these forced induction posts of late. It's ridiculous. If I moderate, I get threats. If I let them go, the site will quickly fill to the tits with useless "Where can I get terbocharj fOr my caR?" type posts and no one benefits.

So here's an answer or two. Perhaps a search in the future will turn up this thread and someone will get some use out of it.

AFAIK, there's only one maker of turbo kits for the MX6/Probe. It's Knight Turbos (formerly known as ATS, run by Thomas Knight) and their website is at http://www.geocities.com/knightturbos/. I've seen rumblings on Probetalk's Forced Induction Forum about "Turbo Tom" and "Ludespeed" but I will leave it up to the interested reader to search there themselves for these topics.

In the majority of turbo 2g-MX6 and Probes, you'll find the owner has not bought a "kit" but has rather bought components and fabricated (or had fabricated for them) their own custom set-up (Toastier and Mici come to mind, as do Ross Lapkopf, Dan Dunhem, Darren Pemberton, Allan Wong, Mike Pazsti, Andrew Brownsword, Rafi and so on...)

A "kit" might consist of, but not be limited to, the following components:

• a suitable turbo
• a Walbro 255LPH in-tank fuel pump
• a Vortech FMU
• custom pre-turbo air filter & cold-air intake
• FMIC (intercooler) if there are plans to run more than 7PSI
• custom-bent exhaust and intake piping. On the V6, clearing the cross-member under the engine may present problems
• AN fittings & braided line for the turbo oil supply & drain
• battery relocation kit
• a turbo timer is a good idea
• upgraded clutch
• blow-off valve
• untold numbers of goodies ranging from nuts & bolts to silicone couplers

I've probably left out more than I remembered.

A turbo installation on a KL (V6) or FS (4-cyl) is not an easy task. There are many details, much fabrication required and a ton of skill. It's easy to hurt the engine badly by a poor or low quality installation or by getting overzealous with the boost. With cast-aluminum pistons and skinny little rods, the engines are limited to about 9-PSI intercooled. If you want more boost than this the pistons and rods will need to be replaced with upgraded parts. Fueling then too becomes an issue. You can't run a 15-PSI car on an FMU: you need bigger injectors and/or supplemental injectors to give the added fuel. Higher-capacity injectors are expensive and tough to find (for the V6 at least.) Supplemental injectors are always a "hack" on these engines because they can't guarantee even fuel distribution in the manifold. On the V6, there are 6 pistons...it only takes one of them to burn to turn the whole motor into a doorstop.

Twin turbos sound nice on paper but would be a nightmare to install. TKT makes a kit from what I hear but I've never heard of anyone actually installing it. You can't run any additional boost with TTs (the engine is still mechanically the limit), the mounting and plumbing would be, basically, twice as complex as for a single turbo.

A single-turbo, intercooled, well-done setup should be good for around 240WHP on a V6. On the I4, output in the 180WHP range shouldn't be out of the question (though I'm not aware of anyone who's dyno'd a turbo 4.)

Please feel free to add value to this thread. I'm sure there are people with more turbo experience than I (Mici? Toastier? Rick?) itching to contribute and/or correct what I've written here.

Edit: In an effort to stave off some of these spurious turbo posts, I'm making this sticky. Value-adding posts will be kept, insipid, silly, stupid or incorrect posts will be deleted without prejudice. Perhaps if this thread condenses the boards' collective turbo knowledge (and there's quite a bit) into a single, concise thread, we'll see a reduction in the sickening repetition of the above-mentioned type of thread.

[Coenraad]

http://www.geocities.com/knightturbos/promaz.html

[Mici]

That was a high quality post once again, Mike. I don't know what there is to add for that.

All I can tell by my experiences is that if you do it right (the custom way, cause there haven't been a "kit" that'll fit right on for 6, though ludespeed.com kit [for PGT!] is supposed to be better quality kit than tkt) you will gain a lot of better performance and acceleration than N/A engine would.

But be aware, custom made systems are very rarely totally problem free. There will be a whole lot of job after the actual turbo install to get it working allright (not to mention that it would work purrrfect!). When making a custom system, you'll need to be familiar with the basic principles of turbo components and how they affect/work with the rest of the setup.

I myself had very good place to build my own stuff and I have access to professional garage/bodyshop tools so that made the thing a whole lot easier. Plus you need to be creative, you need to know how to weld or you need to be ready to learn it.

Even with all the work I made by myself, it all ended up costing (is it ready yet? I dunno. There is still stuff that could be done otherwise to be more near perfect) around $2000. It would be more but for example piping components, I had opportunity to use our business discount and had them for cheaper price.

So what do I recommend for people who wants to do this anyway? Well, I recommend you to gain as much of knowledge about turbos as possible. There are good websites that does explain this very good and then there is our little turbo bible "Maximum boost" by Corky Bell. That book is very valuable to learn how to do the trick and it tells you what you should avoid. People at probetalk always recommend this book and I have a copy in my bookshelf and I like the book. It took over a year of careful reading and self educating for me to be "ready" for starting a project like that. And I had one of the guys at our shop helping me out who had put an aftermarket kit on his Mitsubishi.

But afterall, with whatever problems the turbo might bring to me, I'm overall very happy that I did it. I doubt that I would never have afford to get a car, right from the shop, that pleases me powerwise and appearancewise. Now I do have one. It will take a lot of money to be even near perfect but I think it will all pay off when you first time drive with your turbo'd car and slam the pedal to the medal on 3rd gear. It always makes me grin like this .

I hope this is considered as a quality post too and gives you something to think about before starting on with your projects. Everytime I see someone who has joined the club of boosted KL series engines, I'm glad to salute them and raise my baseball cap for people who has been so much dedicated to their dreams that have made it reality. Sounds good, eh?

Mici

[Rick]

First Mike made it hard to add to the thread, then Mici has to beat me... Nice posts, guys. I think all I can contribute is turbo sizing choices.

For a setup only hitting a max of 9 psi, you're going to want a really small turbo. I'd look for a 14b out of a 1g 5-speed DSM, or a T25 out of a 2g DSM, or even a 13b out of an automatic 1g DSM. You may ask "Why does it have to be out of a DSM?" or "Why are you pushing DSM turbos when there are so many others to choose from?" Well, it's because DSMs are probably the most common turbocharged non-deisel cars in the United States, so you've got a lot of junkyard choises. Any small turbo will work.

The problem with larger turbos is that they give a lot of turbo lag - lots of hesitation in the low rpm while the exhaust pushes the turbine, trying to spool it. The bigger the turbo, generally, the more lag it will have. When you've got a huge turbo, it will take anywhere from 3500 to 5500 to spool, making it a pain in the butt to drive in city traffic. My HRC Super 20G, for example, hits full boost (23 psi, last time it ran) at about 3700 rpm, and my Talon is about as slow as my Tempo before it happens.

The problem with small turbos is that they get overrun quickly. On my 2.0L Talon, the 14b hit full boost at about 2500 rpm. On a 2.5L 6, it should be even quicker. However, on my Talon, that turbo starts to run out of air around 6k, and the car just about shut down after 6500. This can be fixed by porting and clipping. Porting, obviously, allows the turbo to flow more, so it isn't as much of a restriction. Clipping involves actually cutting off parts of the fins of the turbine (exhaust fan), which makes it spool slower but hold boost much longer. I've always recommended going this route when turboing a 6, and I always will.

they were all good posts i learn some interesting things, do you guys know any good websites that have more info on turbos? there is still a few things i dont know about them that i would like to know more on....thanx

[MXSixG]

I have a weird question... is it posible to have a twin-turbo setup were you have a large and a small turbo...... the small turbo would help with that lag (hesitaition that the large turbo has at low RPMs)... once the engine reaches the high RPMs, the large turbo comes into play.. ???? just an idea... Would that work?

[Mike 94PGT]

Originally posted by MXSixG
I have a weird question... is it posible to have a twin-turbo setup were you have a large and a small turbo...... the small turbo would help with that lag (hesitaition that the large turbo has at low RPMs)... once the engine reaches the high RPMs, the large turbo comes into play.. ???? just an idea... Would that work?

This is precisely the type of set-up the 3rd-generation RX7 uses. If you've ever seen under the hood (specifically, under the intake manifold) of one of these cars, you know it's a control nightmare with solenoids and vacuum lines literally up the wazoo and engine management computer programming to match. in addition, the castings for both the intake and exhaust manifolds include passages for the various flow pathways and valves and whatnot for routing. It ain't pretty...

Here's the thing: lag in a turbo system is usually caused by a large turbo. A large turbo, with large compressor and turbine wheels, takes a while to spool up to a speed at which it'll make boost. Such a turbo is generally able to make tons and tons of boost though so it's suited to high-flow, high-power applications. You'll notice that "moderate pressure" turbo cars like a 1.8T Volkswagen have very little lag because their turbos, while not cranking high amount of boost, are sized to spool quickly.

The KL-motor, with stock internals, is not an engine that can take advantage of the large-boost capability of a laggy, flow-capable turbo. You'll be mechanically limited to 8-PSI (if intercooled) or so and so you don't need a large turbo. A small, spin-happy turbo like Rick mentioned (T25, 13B or 14B etc) will happily spool up just 8-PSI into a KL with little lag.

A TT set-up sounds "sexy" and it'd make for a neat bench-racing topic but it's not practical or worthwhile for these cars. If you still feel the desire to pursue such a project, you've got a ton of control theory & fabrication homework to do to get it working right.

[Mx6phanatic]

hurry, somebody put a sticky on this thread. Once again, the "Big 3" come through. Nice posts gentlemen.
-----matt

[Druro]

I'd just like to add the DSM's aren't the most popular turbos. Look at 2.2 Dodge Turbos. I see 7 or 8 of them at yards to every one DSM.

[Rick]

Yeah, but the turbines are designed for low-end power. They can't breath at high rpms.

[Millsie]

In terms of plumbing wouldn't a supercharger be slightly easier to set up. Specifically a roots style blower. I know RR racing has one on there probe and the install looks super slick. There isn't much room in our engine bay to begin with. If there are intercooler pipes and turbo exhaust pipes running around under the hood it would become fairly crammed in my humble opinion. You could keep a roots blower down around 5 or 6 psi and see some nice gains across the entire powerband. Ofcourse then there is the question of mounting the drive belt system...is there a detailed write up anywhere of supercharged KLs?? I assume most guys who do supercharge go with a roots blower but have you guys heard of anyone running a centrifugal (spelling??) system??

[Mx6phanatic]

i think one of the of the reasons that very few superchargers are in use on our cars right now it because they are less efficient than the t/c, and while both require a lot of work, there are more resources to refer to if you are going to turbo because of the number of people who have already done it.
-----matt