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Discussion Starter #1
I just bought a turbo off of craigslist. some guy was selling the turbo off his lebaron for 10 dollars and the deal was just to good to pass up considering this turbo worked. Anyway now i have a turbo that i am considering remote mounting, like a squire turbo system. My question is does anyone have any information on remote mounting a turbo on an Opel Gt with the high compression engine?
Thanks
Sterling
 

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I just bought a turbo off of craigslist. some guy was selling the turbo off his lebaron for 10 dollars and the deal was just to good to pass up considering this turbo worked. Anyway now i have a turbo that i am considering remote mounting, like a squire turbo system. My question is does anyone have any information on remote mounting a turbo on an Opel Gt with the high compression engine?
Thanks
Sterling
There two very different systems.
The k car turbo needs to be mounted very close to the exhaust valve for it to spool up properly.
 

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what is a K car turbo, and why will it not spool up from a remote mount?
It's either a Garrett T3 w/ .48 AR, or a Mitsubishi TD04. Directly mounted to a 2.2 litre exhaust manifold, it'll start boosting at about 1800 rpms and hit peak boost by around 3000 or so.

But stick it on a 300 cc smaller Opel engine, and mount it by the rear bumper, and you'd be lucky to start spool at 4500 rpms! And since redline is at 6300 rpms, and peak power at 5200 rpms on the Opel, you're looking at a VERY narrow powerband. You'd be better off with a smaller Garrett T25 from something like a 300 ZXTT (they have two of them) in order to spool up faster. Basically you need to size the turbo a LOT smaller than you would if it were bolted to the engine. Besides the distance the exhaust gasses have to travel and the loss of velocity that accompanies this, a lot of the heat energy is dissipated by the time it gets to the turbo (hot is 'good' when it comes to spooling turbos).

Don't forget you need a remote oil pump to return the oil from the turbo ($$$), and you MUST run coolant lines if it's a water-cooled turbo (all Chryslers are IIRC).
 

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Opeler
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I've done it before. I mounted a turbo from a carbureted 2.3 L Ford up front by the battery. It worked out to be a nice place to stick it. I probably posted some pictures somewhere on the site. It added about 25hp.
I agree, a small newer turbo is better for this kind of application. As suggested the T25 would be a good fit. That old airesearch turbo definitely took a while to spool up, but that also probably had quite a bit to do with a couple of mistakes I made on the exhaust pipes. Remote mount turbos when done right are plenty potent. If you have any questions I can give you some pointers from my experience putting a system on a 1.9L GT a few years back.
 

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Discussion Starter #6
thanks for all of the info. I did not know that this was a water cooled turbo, it is an m27/t3 garrett air research turbo, and other than that i cant say i knew a lot about it. i just figured for 10 bucks i really couldn't g wrong considering it worked. BigBen I would love to have some more info about what you did with your 1.9 turbo project, and Bob or anyone else, if you could suggest a better turbo to use for a remote mount setup that would be great, because i am pretty sure i want to do a remote mount turbo but, i dont want to spend 4 grand for a squire turbo system. also just for reference my Gt is an automatic so it seems like it is always at a higher rpm.
Thanks
Sterling
 

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Discussion Starter #7
Ok after a little more reading on turbos I am now thoroughly confused. Ok so here are the questions that I have now; with a small turbo like a t25 wont it cut off boost at higher rpm's? Also if I mount a turbo remotely do i need an intercooler or does the long length of pipe back to the engine act as an intercooler? Also where would i get a blow through sstem for a 32/36 weber or would that have to be custom made? thanks for all the info and help, i really appreciate it.
Sterling
 

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Ok after a little more reading on turbos I am now thoroughly confused. Ok so here are the questions that I have now; with a small turbo like a t25 wont it cut off boost at higher rpm's? Also if I mount a turbo remotely do i need an intercooler or does the long length of pipe back to the engine act as an intercooler? Also where would i get a blow through sstem for a 32/36 weber or would that have to be custom made? thanks for all the info and help, i really appreciate it.
Sterling
The t25 is a small turbo compared to many others...like a holset 40. Though for a 1.9 cih with out major head work and a serious cam you won't be limited by it's potential output, especially if you are planning on going with a blow through 32/36 setup. Intercoolers will always help, but from the boost that this set up would probably make you should stick with a very small one to limit the pressure drop across it. The blow through system would have to be made.
 

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Ok after a little more reading on turbos I am now thoroughly confused. Ok so here are the questions that I have now; with a small turbo like a t25 wont it cut off boost at higher rpm's?
Boost won't 'cut off' at high rpms, but a smaller turbo will definitely run out of efficiency at higher boost levels.

However the real question is: How much boost were you intending to run on a stock high compression 1.9 with a carburetor? You do realize that this is a recipe for destruction of course? What were you planning to do for ignition? You'll need higher spark energy for one thing (MSD or similar), and if you are using an early distributor from a high compression 1.9 the use of boost+high compression+carburetor+lots of ignition advance (as much as 52°!) will not be nice to the ring lands. You'd be better off with either a 1975 distributor OR modifying a 1971-1974 distributor. You'll want no more than 22-25° total timing, otherwise things might go boom...

Also if I mount a turbo remotely do i need an intercooler or does the long length of pipe back to the engine act as an intercooler?
Generally intercoolers are not used with remote systems. As you said, the distance the air has to travel usually drops the temps.
Also where would i get a blow through sstem for a 32/36 weber or would that have to be custom made?
Years ago that stuff was readily available but not so much anymore. Probably because so many engines blew up running carburetors and turbos....

However you might check Turbo City. I know they used to have the carburetor 'hoods' for Weber carbs 20 years ago (last time I tried a turbo with carb!).
 

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And I might add . . .

Boost won't 'cut off' at high rpms, but a smaller turbo will definitely run out of efficiency at higher boost levels.

However the real question is: How much boost were you intending to run on a stock high compression 1.9 with a carburetor? You do realize that this is a recipe for destruction of course? What were you planning to do for ignition? You'll need higher spark energy for one thing (MSD or similar), and if you are using an early distributor from a high compression 1.9 the use of boost+high compression+carburetor+lots of ignition advance (as much as 52°!) will not be nice to the ring lands. You'd be better off with either a 1975 distributor OR modifying a 1971-1974 distributor. You'll want no more than 22-25° total timing, otherwise things might go boom...


Generally intercoolers are not used with remote systems. As you said, the distance the air has to travel usually drops the temps.

Years ago that stuff was readily available but not so much anymore. Probably because so many engines blew up running carburetors and turbos....

However you might check Turbo City. I know they used to have the carburetor 'hoods' for Weber carbs 20 years ago (last time I tried a turbo with carb!).
. . . and THIS should tell you all you need to know about carb/turbo use!
 

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Discussion Starter #11
Let me first start by saying thatk you to everyone that has given me information on this topic, I am really learning alot. in terms of how much boost i was looking to add, I am going to run a small number like 4-6psi as I really dont want any adverse affects on my engine. Also I was unaware that in order to accomodate the turbo that i would need a higher spark. It seems that at this point based on what I am hearing, that it is going to be an expensive and engine life shortening project. However i still would like more info as it still may be the way to go.
Thanks
Sterling
 

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boomerang opeler
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better to start off by going to an injection system for fuel from a 75 manta then you can forget about the hard part of getting a carb and turbo to work together

pop some low compression pistons from a later 1.9 in ( sure some one here would do you a swop as most want the high comp pistons ) and chat nice to rally bob about exhaust side info ( he has a great thread about making one up to add a turbo here some place ) and you can have a long life high power opel engine no problems at all

then all you have to do is worry about the gear box and back axle going to lunch when you give it some one day :D
 

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However i still would like more info as it still may be the way to go.
Another thing to keep in mind is to get a great fuel supply. If it leans out boom. I would start with a A/F ratio of 10.5-1 @wot or maybe even a tad richer.
 

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Discussion Starter #14
What are the advantages to running the low compression pistions with the turbo vs. the high compression pistions that are already in there? Aslo what is the difference caused by running fuel injection vs. working with a blow through system? I am sorry if theese are stupid questions but i am trying to learn everything possible about this before I do it.
Thanks again
Sterling
 

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boomerang opeler
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turbo engines normally run lower compression to combat pre detonation in the pistons theres a point when air and fuel mix under compression will explode on it own , too high a compression and bang no more ring seats on the pistons , running lower compression helps fight this and you lose off boost performance but gain when on boost

as for injection

a carb system thats blow through has to be sealed from normal atmospheric pressure so it works at the pressure the turbo is giving , if not the pressure drop in the venturi does not happen so no fuel into engine, with an injection system the fuel is added mechanically so it is not effected by the increased pressure from the turbo + most injection systems give a boost in performance to start with
 

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Discussion Starter #17
Ok, that makes alot of sense as to why the lower compression pistons. I know that it was said that ring seats break with pre detonation but if I am running low boost like 4-6 psi, will I still have the problem with predetonation or does that only occur when running large psi boost? Also what is the problem with sealing the carb off to all for the boost to come in, does that cause ill effects to the carb or to the engine?
Thanks again you guys are rally helping me to understand this all.
Sterling
 

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Opeler
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Going back to the question about the question about the spark. I was using a Petronix Ignitor and Flame thrower coil and that seemed to be sufficient. (I was getting about 3-5 psi boost) At the time both together only cost about 100 bucks. You can also disable the vacuum advance to reduce the total advance, or rig it to work backwards so when the manifold is pressurized it retards the timing.

There are still quite a few people that run carbureted turbos on VW's. These are usually wet turbos, or draw through. Draw through turbos are easier to setup than blow through but the challenge is that the intake needs to be down hill from the turbo or you get a very lean mixture when the turbo is not spooled up. Kind of hard to do with a remote mount turbo. I originally had mine set up as a wet turbo and boy was it guttless until the turbo got spooled up. It would scream from 3800 rpms to redline, but below that forget it. If I had to stop on a slight hill I'd have to rev the engine and burn the clutch to get the turbo to spool up before I could go.
 

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While were into the spark section. Another hint would be to only use copper plugs. You'll want the widest gap as possible...but to wide and spark blowout can cause the insulator to break and run through the engine.
Get some low lead fuel ie AV100 it's easier to read the spark plugs than unleaded. Make a hard pull then shut it down at the same time of letting off the gas.
Coast to the side of the road and pull the plugs. Happy tuning!!!
 

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Discussion Starter #20
Thanks for all of the info I really appreciate it. I spoke with my mechanic who just rebuilt the motor in my Gt and he said that having the auto transmission and the a/c as well as having the high compression pistons was not an ideal situation for running a turbo. He told me with the way the engine was built, that if i ran a turbo i would probably ruin my engine and I really dont want that as it is just rebuilt. Anyway i have decided at this point that instead of putting the turbo onto my current Gt wich is the automatic, I have another non running Gt in my driveway which is a stick that I bought as a project car and I am going to start working on that as my fun powerful opel, and I am going to keep the automatic as just a fun original. I am thinking that for the stick opel i amgoing to put in a 2.4 liter and I will put a turbo on that. For now however i just have to save my money and start planning what i am going to do to the stick gt.
 
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