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Discussion Starter #1
I have gotten some emails about an FI turbo. so I'll post my reply here so every one can get an idea of what it will take to do it themselves.

We have designed, but are not going to build an FI turbo kit. We simply don't think we would ever sell enough to recover our initial investment. Here's what you would need to do it right.

1. FI intake manifold & throttle body from '75 or later. You could also go to a custom intake so that everything would fit a little better and would really be the best way to go. Then you could use a throttle body from TWM Induction (www.twminduction.com)
2. RC fuel injectors. (www.rceng.com)
3. Fuel pump and "plumbing" from and return to fuel tank. We use Earls. It's a little expensive, but really gives that "extra" look. (http://www.hyperstop.com). While you're at it, put on an oil cooler... you're engine will thank you.
4. Intercooler... we can custom make one for you $480
5. Custom header - the one we have in our present kit won't work because a different turbo location will be needed.
6. Engine management computer. The Opel stuff won't work with boost, so we recommend a Haltech. (www.haltech.com)
7. Sensors to "feed" the computer - again the Opel stuff won't work - I won't describe everything here, but you can get what you need from Haltech
8. Oil pressure line to the turbo, and return line to the sump.
9. "Plumbing" from the turbo to the intercooler, and from the intercooler
to the throttle body.
10. And of course, the turbo.

I know I've left out a bunch of stuff, but this covers the "biggies".
We recommend Haltech, because that is what we have been using for all of the stuff we've been doing for the "rice burners" and it works out very well, and it is the most cost effective computer.... others are good so check them out too.

Have fun dreamin' and schemin'
 

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Bob,
Could you tell us all a little more about your current turbo kit? How much carb tuning is involved to get it "streetable"? Do you have any dyno tests on it?
Thanks,
James
 

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Discussion Starter #3
There's another section on the site "Opel Bolt On Turbo" that has some discussion of the kit. Since there isn't supposed to be any "advertising" on the site, I'll limit this to a general discussion. (Contact me directly by email if you need more information.)

Carb tuning is necessary for any performance modifications, so a turbo is no different. Make any big change to the engine and you will have to "dial in" the carb. The best thing to do is get a good Weber book (or for whatever carb you have) and understand what all of the jets and orfaces do. Then here's the "drill".

Road test the car at constant throttle for each of the various jet ranges... part throttle, mid throttle, and wide open throttle. After running a few minutes in a given range shut the engine off and coast to a stop. If you slow down with the engine in gear or running, then you will "contaminate" the test by running the engine in a range other than the one you are adjusting for.

Pull the spark plugs and check the color on the tip. They should be a chocolate brown. If they are a lighter color, then you are too lean... bad:( If they are dark then you are too rich. Change the appropriate jets and try again. Keep trying until you get the chocolate brown color. If you have to compromise, make it a little too rich.

Do this in each throttle range. Wide open throttle can be a problem. You have to run for a minute or two so you will not be at legal speeds unless you've got a long steep hill to go up.

You can see why a rolling road (chassis) dyno is really the best way to "dial in" the carb. Then you won't have to worry about the cops and changing jets along the side of the road... it's just that every one may not have a dyno facility near them. You will need a couple of hours on the dyno and a hand full of various jets.

By the way, this doesn't apply to just performance stuff. I bet that if every one who reads this goes out and checks their plug color this week-end, half of them won't find the "chocolate brown"... this doesn't apply to Rally Bob 'cause I'm sure he "dials in" his stuff as soon as it is running.
 

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Discussion Starter #4
I just remembered that I wanted to answer... well, only sort of answer your questions about dyno tests on the turbo kit.

Yes, we have dyno tests, but we have a philosophy about HP claims. There are two kinds of claims... lies, and damned lies.

About 2 weeks ago we had a customer who bought a couple of bolt on "magic" items for his Toyota. He came to us to do before and after dyno testing. Each of these items were supposed to make about 20HP each. This stuff cost him about $500. (I won't tell you what the parts were 'cause then I'll get sued by the manufacturor)

After about $250 worth of dyno time we were able to get about 3HP more than he started with... 2 HP from the first part and only 1 HP from the second.

So, be suspicious of HP claims. Frankly, people will tell you anything to make a buck. We make no specific HP claims about anything. Every engine is different, and the results will vary depending what other work is done to the engine. So anything I would tell you would be a lie. Yea, we would probably sell more kits if we made some outrageous claims... but ... well... I'll just leave it at that.
 
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