derryck

Aus,
Additional injectors is not the way to go... that was our initial intention. I had actually bought a secondary set of injectors and I think an SDS controller. I'm not sure why we decided not to go that route but it was Dwight's decision and I'm sure he made it for a reason. Again... I stress, I think a simple phone call to Dwight at Speedcraft would save you ALOT of time and ALOT of problems. They would be able to provide you with much more useful information than myself or Chris.

Team Hybrid

[QUOTE]Originally posted by ChrisD
[B]Heya AusS2000, just came across this thread today, and I have to say I'm impressed. While you are undertaking a project that has a lot of serious technical issues, I'm sure that your end product will be very lucrative to a lot of people. I just have a couple of comments which I don't think have been touched on.

While Team Hybrid may not have phrased it the most "consumer-friendly" way, he does have a point about tuning. By drastically changing the shape of the fuel curve, the stock ECU will not be well equipped to provide the proper amount of fuel for each spark cycle. The way that we have "augmented" the stock ECU (since it doesn't read boost) is by wiring it up to a Vortech FMU which increases fuel pressure according to the amount of boost. However, this produces a torque curve that is a little lumpy, as the ECU is programmed specifically characteristics of the engine. Narrow throttle at 4000 rpms while at about -0psi (roughly equivalent to full throttle on an NA application) will not be providing enough fuel and you may find yourself slightly too lean (although not dangerously so). WOT at 4000 rpms and at full boost, you may find yourself too rich (just from personal experience). When I first got my turbo, I didn't have the VAFC installed and although I ran a higher boost than it seems you are planning to, I had "lumpiness" problems, as small variations in the optimum fuel curve differed from the shape of the stock fuel curve af various throttle percentages. Technically, it would be better described as the shape of the fuel PLANE (throttle % one axis, fuel % another axis, rpms another axis) was different in the turbo and stock application. The VAFC is a small bandaid for this in that it allows tuning at 3 throttle levels, 0-10%, 10-50%, and 50-WOT (which is also configurable). A better solution is Motec or the AEM EMS, although obviously far more expensive. 300 bucks for the VAFC and a couple hours tuning, versus 1-2,000 for the engine management systems and a good amount of tuning.

ChrisD

Vortech FMUs cost 140 bucks from vortech's site. The VAFC provides a basic amount of "tunability" but like I said before, it's not as precise as a full engine management system. It'd be similar to trying to write in a 6 inch notebook with a 6 foot pencil... that's dull. It most likely would be enough to get you by, however. For all intents and purposes it probably would be good enough if you are going to make a basic kit. Tuning it really isn't that big of a deal. Find someone who knows their salt and shell out the 100-200 bucks to tune your VAFC properly.

From what it sounds like you are trying to do, you are trying to make a "mass-consumer" version of the speedcraft turbo, getting all the good points of the Speedcraft setup and the Comptech setup, for a little cheaper than both. While this is basically what everyone wants, my only suggestion would be to really research how much the various parts are going to cost, and be ready to test out that solution yourself. From the description you have given, the turbo itself is going to be the most expensive piece of the puzzle. You probably want a smaller hi-fi ball bearing turbo, one that spools up quickly but perhaps doesn't have quite the potential (and therefore quite the spool-up time) of the turbonetics 60-1. You will most likely want a ceramic ball bearing turbo, which will spool up quicker but cost quite a bit more than a standard turbo. Although you will have to call turbonetics (and in your case, I would suggest you do) to find out the exact pricing, you can most likely expect to pay anywhere from 1200 to 3000 dollars, depending on the options, for just the turbo. I suggest you peruse

http://www.turboneticsinc.com/catalog/index.html

with your mechanic to figure out exactly what you need. You might (unfortunately for the rest of us) find that the parts you need may end up costing slightly more than you thought to make a reasonable profit.

As far as reliability is concerned, I'd personally be a little worried at 6psi on such a high compression without an intercooler. 4 psi is actually quite "snappy" and if you can get to 4 psi relatively quickly, I think you might make a lot of s2000 owners happy. It wouldn't be boatloads of power, maybe only 40-60 more horsepower, but you might be able to get it down as low as 3000-3500 rpms. The stock turbos on Audi S4s spool almost instantaneously, and it gives it the feeling of fountains of torque. I call it fake torque, but it feels all the same. At 4 psi, I have no worries with reliability (on an aside, I've really been thinking that our block/pistons/rods are exceedingly well crafted and might be able to hold up to more than we've been thinking.. I haven't heard of many piston/rod failures, have you?). As long as detonation isn't an issue (which you should really be aware of without an intercooler) you should get just as many miles out of this block as without the turbo.

And as many times as he's said it derryck does have a point, in that Dwight at Speedcraft has been through this before, and really may have a few helpful hints for you. It can't hurt to speak with him and/or someone at turbonetics.

If I've said it once I'll say it 100 times. Going FI is not going to be easy or cheap on an NA car, but done right, well.. hang on.

ChrisD

[QUOTE]Originally posted by Team Hybrid
[B]

heyyyy... I say potato ...you say pohtahto!

AusS2000

Thanks again.

The more I think about it, and IC is a good idea. Not 'because turbos have ICs' but because not all PSI's are the same. P1V1T1 = P2V2T2. What that means is that 4psi at 300 degrees Kelvin has 50 percent more air in it then 4psi at 450 degrees Kelvin. So 4 psi without an IC may be providing very little in the way of air, yet increasing the propensity to detonate.

We'll see very shortly.

Team Hybrid

none taken Chris.
I just do not have the patience to type all the details out. Nor do I have all the answers. Thank you for sharing your experience and knowledge of the situation.

tze

AUS - chiming in on the whole FMU/ECU issue -

Don't forget that Aust is the place where NUMEROUS ECUs are manufactured and used - you can source them here domestically for far cheaper than in the states. Even if yu were to use an imported unit such as the Unichip - (the unit costs AUD$600-700) MUCH cheaper than an AEM EMS or similar unit - and easily as powerful

ChrisD

[QUOTE]Originally posted by tze
[B]AUS - chiming in on the whole FMU/ECU issue -

Don't forget that Aust is the place where NUMEROUS ECUs are manufactured and used - you can source them here domestically for far cheaper than in the states.

derryck

I believe that we had detonation running straight pump gas at 4 psi when VTEC kicks in before my car was tuned. Once you get into things a bit more I think you'll find that VTEC and post VTEC tuning are something that must be dealt with. When we first put my car on the dyno it dove off the bottom of the scales (fat I think) once VTEC hit. Sorry for the random thought nature of this post... just trying to post things as they pop into my head.

cbender

Aus, I'll send you a PM that might be of some use to you.