Brent 930

I have been tinkering with my WUR's (stock and enrichment) to see if could help lean out in the low to mid (pig rich) but then get rich at the top end. This brings me to the articles on how to make your WUR adj. BUT, what I have found from hours and hours of testing is you can't lower your warm control pressure low enough to get more fuel up top on enrichment without jacking up your cold start pressure. 3.65bar seems to be the magic warm pressure # while maintaining a good cold start. BUT, again what I have just learned from my curiousity of how the enrichment works, it looks like I can make an adj. to get more fuel up top from a stock WUR! In fact with taking a piece out I can make a stock WUR run like Lee's enrichment but I don't think it will work as well. Either way my other thoughts about how much if any more fuel you will get at the top end using Lee's enricment or probably any other is going to be around another .5:1 less than stock. This can make or break you up top when your out of fuel and with CIS you need every last drop you can get.

I still don't believe varying the system pressure will help you at all in getting more fuel but just to ensure you are turning on the injectors and have good pressure for the best spray pattern possible. Then the mod everyone has heard about that Steve W. does is applicable if your already running an enrichment device since the lower control pressure will allow you to run a lower CO at idle thus giving you the extra room up top to max out the fuel pin ( remember the last 1-2mm won't get you anymore fuel). With the stock WUR you have to compensate by cranking up the CO to do kind of the same thing. Just my .02 cents

I will continue my investigation until I have exhausted all possibilities and let everyone know what my conlusion is on the possible extra enrichment of a stock WUR. That would be very cool if it can be done. Right now I'm trying to adj. my Rice fueler to enrich with 0 vacuum or on boost.

Brent

Brent 930

Update,

I have done some more research and alot of work since my last post. I couldn't change the Rice fueler so it will enrich at 0 vacuum even though Lee says he can do this. Personally I figured on having a better chance with the stock one by design. Quick note; based on the length of the pressure pin inside determines alot of why the pem (where people make then adjustable) is at the height it is. Therefor I don't recommend changing it or even making them adj. because it isn't worth it...trust me on this one. Now the fun part, I used the lower half of the Rice fueler that controls the plunger (more travel than the stock one for more fuel) inside for enrichment and then robbed the spring from the stock one. This made the WUR act like a stock one (where it will enrich at around 5psi of at least on mine) BUT, I get the lower control pressure for the fuel up top) Now that all of my fuel pressures check out I need to tune the car and drive it to make sure everything works right for real. Will post again when I know the final results. Then another dyno session will be in order if all goes well.

Brent

SoCal Mike

Keep up the great work Brent, I'm living vicariously through your experimentation, which is keeping my "better half" in a better Mood
I'm leaning toward trying out the turbo link as an add-on. This month's upgrade is going to be a wide-band O2. I was planning on using the tech-edge which will be available soon however I just heard about a company Innovate Motorsports that is also just releasing a wide-band. They are located just about 20 miles away from me, I'll check them out on Monday. Regards, Michael

Brent 930

Thanks,

Well, all looks good after just a little tuning and driving it around for a while then letting it sit and restarting it. So now I have a mechanical Andial fuel enrichment device so to speek. I'm sure Lee thought of this already but with the stock spec. of fuel delivery from the fuel head he did the right thing. I'm leaving my CIS tester hooked up in the car so I can keep track of things. The warm control pressure is between 3.7-3.75bar which seems good. It just seems like anything lower than 3.65 (even though 3.45 is the low spec.) could give you trouble with the cold start pressure. Anyhow I will need to recheck the fuel curve the next time I do a dyno pull. Then I will decide if I will get that Greddy Rebic IV and map out the fuel curve the right way. If this proves to work well and I can find out from Lee where to get the lower part of the WUR, I could convert any stock WUR with little or no tunning at all. I would just need to verify all fuel pressures on my car. I haven't heard of anyone who as done this yet. Still need the hardcore proof on the dyno with the fuel curve to really confirm this. Will let everyone know in due time.

Brent

Brent 930

Regardless of the fuel curve it works and I now can convert any stock WUR(assuming it's good) to work like Lee's or the one I did. Will let everyone know if and when it's a go for business.

Brent

m42racer

Brent,

The guy's at Link USA already have done what you are doing, but they did it digitally. They control the pressures based upon RPM, and manifold pressure. You can map the pressures (A/F) to whatever you want. No more mechanical mods. Need to raise the pressure/ lower the pressure, to suit a certain A/F at any RPM/manifold pressure, just change the duty cylle of the Injector.

This is not really the right way doing it, and they have addressed this also, but making the lower Injector blocks to accept both the mechanical Injector and a electronic one. That is the better way to provide more fuel accurately.

The pressure adjustment is for those who wish to spend limited $ and get the changes in a more coarse fashion. Well at least its mappable and is based upon RPM and engine load.

Brent 930

Yes, I mentioned that in an earlier post about the Rebic IV but at a price. Were talking 3 times more money than what I'm going to offer and it isn't messy.

m42racer

$ or cost are very inportant. I did forget to mention the other very useful function included in their Turbolink. It has full datalogging, can receive and datalog the O2 sensor, and can drive a completely separate Ignition system, (advance) or intercept and retard (stock CDI). The Ignition system can be stock CDI, or Wasted spark. I think it has some extra drives for RPM or MAP based functions. I think the price is $ 695.00 for the system without the harness. I'm not sure about the cost of this part. Not a bad price for fuel control, Boost control and Ignition control, all in one box. Its PC tunable with datalogging.

But your correct. This may be too much for some. seems very good value when you compare the cost of a Boost controller, Ignition systems and additional fuel controller.

jrogers

I am interested in both of these options. With the cost of a set of pistions and doing a rebuild, a thousand dollars does not seem like a lot to solve this problem. I am more interested in a solution that is stable and repeatable, and does not require a ton of tuning on a continuous basis. Does anyone have a link to this 'Link USA' system that m42racer was referring to, or any other simllar systems?

SoCal Mike

Jim,

http://www.link-electro-usa.com