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Turbo Charging or NOS for the 1.9

6504 Views 26 Replies 13 Participants Last post by  BQS4
Has anyone actually added a turbo the the 1.9? if so I'd like to hear the particulers. Often we hear the theory but lack details like what did the turbo come off of and how was it plumbed into the new setup. I went to TGSIs site and all the links are down..... oh yeah, what happened to spell check? I can't spell.
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Washout, a whole lot of years ago, right after I got my first GT, I happened across an article where a turbo was put in a high? compression 1.9 in a GT. It was an aftermarket kit by one of the turbo manufacturer's not out of a specific turbo'd car. What I do remember was it fit right above the heater box, and with 8 lbs of boost it got the horsepower right at 160HP or doubled stock horsepower rating. Now with saying that, and with what is known about turbocharging today, the claims of the article may have been exaggerated. The price of the kit at that time was about $2000. I was considering that mod to my car, until I learned of an incident from my engine instructor in A & P school. It seems an aircraft owner had a RaJay turbo installed on his engine and was so impressed with the performance at altitude, he ignored the warning placard on the instrument panel about not engaging the turbo below 8000 feet. He engaged the turbo on takeoff and promptly blew all 6 cylinders off the engine block right through the engine cowling. After hearing that I was leary about putting a turbo in my GT until I could figure a way to get positive waste gate controls figured out. :confused:

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I had a turbo GT for a number of years. It had a sprint manifold and a 4 inch U that went under the motor cross member and back up to the bottom of the turbo. This was a suck type setup that pulled through a 45 DCOE Weber facing forward through a hole in the radiator mount. The outlet went to a modified stock intake with a 2 inch coupling. Normal carb mount on the intake was welded flat and an inlet was added to the front right corner. As I remember it the popoff was on the exhaust side and limited the amount of pressure it could produce. By todays standards it was pretty crude but it did put out the ponies. I bought the car when the PO had the wastegate stick and detonated a piston. It was fun but the lag was horrendous. The wastegate had a simple pipe that let out exhaust to below the car and the exhaust started where a standard carb would be. 3 inch all the way out and just cleared the heater box and motor on that side.
OE, operator error, has been the demise of many an aircraft engine. The rajay booster has been on many AC over the years but is also a finicky unit where pilot ablilty has had a great effect on the effectiveness of the unit. I have never used the rajay but like any tool, in the right hands it is a great benefit, in the wrong hands, it's just another hammer beating the hell out of something. I was just interested to see if anyone had converted the turbo out of any late model cars to fit the 1.9. That might be an easier way to get 50 HP than installing another engine combination.
Check out this thread by RallyBob

He details his own fabrication of a turbo EFI 1.9
hes making it for a mantat though not a gt and his setup he said would not fit in the gt do to size and such other things. the gt engine bay is just to small to add more stuff.
After I got the Turbo GT the PO vanished and I started tracking things down. I found out that the turbo, exhaust and head work were over 7000 dollars. He put another 4 into suspension and the rear end. I imagine somewhere around 5 for the body mods and other upgrades needed. Speed is money and this one was real fast. That was mid 80s prices too.
Hey Namba 209, this is sounding like airplane stuff, double the speed equals quadruple the drag or double the power, quadruple the expense;
The theory would be the same for turbocharging a GT versus a Manta, only the actual fitment differs. A GT will have far more heat issues, and far tighter confines to work within. Regarding turbocharger selection, if you are trying to match a junkyard turbo to your application, then the best bet is to establish honest criteria regarding HP levels. Trying to make a 75 hp engine into a 200 hp engine is not easy unless you have the right hardware. You could just boost the hell out of a stock engine, but you'd better have spares!

Choose a turbo from a vehicle with a similar displacement, and a realistic power goal. A common turbo (Garrett T3) to use for a 1.9-2.0 litre displacement engine is a Saab turbo. Commonly producing around 160 hp in a Saab, this would effectively double your hp, if you played your cards right.

As I mentioned in another post, I decided to run a turbo on my father's GT, but some preliminary measuring means I have to do a complete rethink of my manifolding to fit a GT, the ideas I used for my friend's Manta won't work. My initial reaction is the turbo will end up where the stock air filter housing is located (with a custom manifold of course), the intercooler will make up the lower grill opening, and the radiator will be a VW type, mounted at an angle further up in the nose of the GT. I will end up cutting the stock radiator 'firewall' away most likely for more plumbing room.

One aspect that will give me more room is the use of a 2.2 head, with a short-runner custom EFI intake manifold. This raises the intake ports away from the exhaust pipes substantially (2.2's have raised intake ports, by about 5/8"). More freedom of fabrication thanks to this feature....

My turbo of choice will be either a GT28RS or a GT2871 ball-bearing turbo. Neither came in any production cars, they have to be bought new, and they're around $1200. But, they have a flow capability of 350 hp and 400 hp respectively, yet with the modern aerodynamics and ball-bearing center, plus the large displacement engine (2625 cc's), they should provide nearly lag-free boosting plus a smooth power curve.

If you want to get a 'big' turbo that is cheaper, yet can still flow some air for big HP numbers, I suggest considering an IHI VF22 turbo, it's the largest 'bolt-on' turbo made for the Subaru WRX. Costs around $600 new if you look around (try my friend's shop, www.xxtuning.com), and can flow enough air for about 380 hp. It is also a ball-bearing center section, so it spools nicely. I just built a manifold to adapt one of these to my friend's 1.8 litre VW rally car, it comes on boost by 2200, and pulls HARD to 7000 rpms. Made 231 hp to the wheels at only 12 psi boost. Check out the manifold at www.metalmarks.com


edit for spelling...
2nd edit, VF22 turbo is $589 on special this week!
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hey bob it suprises me you kept the cat on the mark 4 golf
didnt it make a lot of noise when you put the tail pipe in!!!!;)
baz said:
hey bob it suprises me you kept the cat on the mark 4 golf
didnt it make a lot of noise when you put the tail pipe in!!!!;)

No seriously Baz, it's a sign of the times. Since rally cars are road-going cars legally, they must now utilize a catalytic converter, and can only run unleaded racing fuel. Leaded fuels are now forbidden. The cat my friend uses is of UK-manufacture in fact, primarily for competition use. It is installed all the way at the rear of the car, so it restricts the flow as little as possible, and won't 'melt-down'.
Bob, I spent some time poking around the xxtuning site, and I have to compliment the graphics and navigation, very impressive and polished. The only thing that stands out to me (only because it was beaten into me in all of my marketing classes) is that a font that is too small or too large, will instantly turn a customer off. Example, the dyno page that explains the advantages of the "Dynapack" system contains a great deal of very valuable information, but it is impossibly small and is not contrasted very well. They have great products and there work looks very good.

Thanks for the information Bob, and others, I was just considering adding a turbo to a stock but fresh 1.9. I have no illusions about making 200 HP but 150 would really be nice and I was thinking you guys might have some suggestions of donor cars to look for. Would it be easier to just use NOS for those rare moments when I want to act out? :) Thanks
Washout said:
Would it be easier to just use NOS for those rare moments when I want to act out? :) Thanks
Certainly easier! However it may end up being addictive, and though the NOS would be cheaper initially, if you became addicted to it (the car, not the driver!), it could start getting as expensive as building a turbo system, since they don't fill those bottles for free. Power is like a drug....
I was just thinking about nitrous and wondering if it would be a safe idea for a 25 hp boost? and would a company make a cheater plate for the intake manifold/weber? how much does a 20lb (or what ever size they can come in) to get refilled and how long would it last with a 25hp boost? I would not try that with my opel now, I may try it with one later on.
NOS is a great tool when used properly. I'm not aware of a 'cheater plate' for the weber but you could have machinest make a simple standoff plate and create your own, it shouldnt be too expensive.The stock engine should be fine with just a 25hp shot, you could go as agressive as 60-100hp but then you need to start looking into the best gas you can find and retarding the ignition. A good rule of thumb for how long bottles last is 10hp per lb per min. As for cost most places charge $3 to $4 a lb and some simple charge a flat rate so a 10lb bottle would be 30 or 40 dollars to refill. A few extras you might not of thought about, bottle blankets are nice since they keep the pressure level regulated in a tank as you use it over time, also purge valves not only look cool but keep the system ready to deal power the instant you hit the go button.
kmon said:
I'm not aware of a 'cheater plate' for the weber but you could have machinest make a simple standoff plate and create your own, it shouldnt be too expensive.
NOS at least used to sell a plate system to fit a Weber, I bought one years ago. 25 or 50 hp shot only. I wouldn't want to go any higher than that unless it was direct-port anyway, distribution is too critical, you'd likely smoke cylinder #2 in a heartbeat as it already runs about 200 degree hotter EGT's.

Don't forget, in addition to retarding the timing, you'd have to consider a colder spark plug range, a stronger ignition system, and a higher pressure fuel pump plus a regulator. The nitrous wants 6 psi, but a Weber wants 3.5 psi, so you need a higher pressure pump and a regulator to drop the pressure only to the Weber, not the fuel jet for the nitrous.
I guess the place to start here is what should I do about the induction system? I have a standard Weber carb system on it now, is that satisfactory or should I be looking to upgrade to fuel injection first? What reading material would you suggest for ideas, I am pretty proficient at fabricating and have a few tools in my shop that can help, vertical mill, lathe, mig, and the usual light tools. My weakness is I have never actually seen a complete turbo setup to understand exactly how everything is plumbed together. I've been following the thread of your turbo FI setup for the manta and must say that is some very creative work. I am certain I can duplicate the work you've done there with one major exception, you know why everything has to be placed as it is and I do not.

I'd appreciate any direction on publications that you might recommend. Of course I have no deadline on my project as you have. I'd love to see your setup and I was looking forward to meeting you all in Carlisle, however, it's ain't gonna happen this year. I ruptured a disk in my neck about two weeks ago and I can’t do anything but hurt. I'm taking enough pain killers to knock out an elephant, that means I can't work and I'm pretty leery of getting round things like my lathe. But this does give me abundance to time to plan the next upgrade to my little toy. I just thought I might start collecting parts like a good used turbo and try to engineer the routing of the exhaust pipes after the turbo, as well as where to mount the turbo.

Thanks for all the input on this thread guys, I know I can get a turbo in here and I'll document the whole thing. Thanks for all your insight Bob.
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Washout said:
I'd love to see your setup and I was looking forward to meeting you all in Carlisle, however, it's ain't gonna happen this year. I ruptured a disk in my neck about two weeks ago and I can’t do anything but hurt. I'm taking enough pain killers to knock out an elephant,
Sometimes life gets in the way of things. Besides the setbacks with the turbo project's donor engine, I've had to deal with a serious sickness in the family, and my own work injury last week which has pretty much left me with no use of my right hand from nerve damage. So no fabricating for a while, if at all. It doesn't look like I'll make Carlisle either at this point.

But hey, there's always next year, right?

Get well....
Sorry to hear about the bad luck Bob, I certainly hope it is only a short term setback. I feel pretty confident that surgery will get me back on the road. Good luck. Gregg
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