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Looking to make your car turbocharged? READ FIRST

Where in FL are you? In my local yard there is a 940 turbo and a few 740 turbos. If you are close to Orlando or Tampa or JAX, check their yards.

You will need to do some wiring extending as the AMM and battery in the N/A is in the opposite sides as the turbo cars. But that is solved in like 15-30 minutes depending on how many times you have to stop to talk on the phone. Also, you need to slap some resistors to drop the voltage to the turbo greentop injectors, which is also not much of an effort. And that is where your electrical mods end. The rest is a matter of slapping ECU/ICU and the other turbo parts.

Although I am not +T anything at the moment, I can't figure this one out from reading. If you are using turbo ECUs, why would the injectors STILL be getting a NA impedance signal? With Turbo computers, wouldn't the signal be low impedance? Or do the turbo cars use resistors and the ecu always gives a high impedance signal?

Also, on the 95ish 940, do they use OBD2? And does that cause any issues?


Just some questions I came up with that I don't see answered. Maybe it will help somebody out.
 
Although I am not +T anything at the moment, I can't figure this one out from reading. If you are using turbo ECUs, why would the injectors STILL be getting a NA impedance signal? With Turbo computers, wouldn't the signal be low impedance? Or do the turbo cars use resistors and the ecu always gives a high impedance signal?

How to make a short story long:
The signal isn't low or high impedance in this case, it is the injector.
The turbo or N/A ecu's are exactly the same regarding the output driver for the injectors (correct me if i am wrong). They work the same. They can switch the same amount of current. The N/A injectors have a resistance of ~15 Ohm, the turbo ones a resistance of ~2 Ohm iirc. Regardless of the computer you are using, the lower resistance of the low-impedance turbo injectors will cause a higher current draw for the computer (Ohm's law). To limit the current the low-ohm (actually called low-impedance because we are talking about a coil - inside the injector) a resistor is added in series to bring up the total resistance. lower current is the result.

The summary: use a resistor pack with low-impedance injectors (like the stock turbo injectors of the 740T/760T/780T/940T/960T). Are you using for example the 850 turbo injectors, those are hi-impedance so no need to add a resistor pack because they have the same 'resistance' as the original injectors that came out of the N/A car.

Also, on the 95ish 940, do they use OBD2? And does that cause any issues?
afaik the latest USA delivered 940's still use OBD1. Only the later European delivered ones have OBD2.
No issues. I am using a 0 280 000 984 ecu from a 1998 940 in my 240. That ECU supports OBD2. No changes to the wiring. The OBD1 diagnostic socket still works as usual (all 4 test modes - the codes for LH and EZK and a check for the actuators (injectors, Efan, IAC, FP, evap) and a check for the TPS etc).
 
How to make a short story long:
The signal isn't low or high impedance in this case, it is the injector.
The turbo or N/A ecu's are exactly the same regarding the output driver for the injectors (correct me if i am wrong). They work the same. They can switch the same amount of current. The N/A injectors have a resistance of ~15 Ohm, the turbo ones a resistance of ~2 Ohm iirc. Regardless of the computer you are using, the lower resistance of the low-impedance turbo injectors will cause a higher current draw for the computer (Ohm's law). To limit the current the low-ohm (actually called low-impedance because we are talking about a coil - inside the injector) a resistor is added in series to bring up the total resistance. lower current is the result.

The summary: use a resistor pack with low-impedance injectors (like the stock turbo injectors of the 740T/760T/780T/940T/960T). Are you using for example the 850 turbo injectors, those are hi-impedance so no need to add a resistor pack because they have the same 'resistance' as the original injectors that came out of the N/A car.


afaik the latest USA delivered 940's still use OBD1. Only the later European delivered ones have OBD2.
No issues. I am using a 0 280 000 984 ecu from a 1998 940 in my 240. That ECU supports OBD2. No changes to the wiring. The OBD1 diagnostic socket still works as usual (all 4 test modes - the codes for LH and EZK and a check for the actuators (injectors, Efan, IAC, FP, evap) and a check for the TPS etc).

Sweet post man thanks. Makes more sense.
 
An even simpler explanation:

A factory turbo 940 (LH2.4) uses low impedance injectors and a resistor pack. An NA 940/740/240 (also LH2.4) runs no resistor pack, so when you swap over the turbo ECU and injectors you need to add the reistor pack too. Essentially you're just copying the factory turbo setup in your originally NA car.

Hen
 
Use orange tops (off an 850 I think) and you won't have to add in the resistor pack. That is what I did and it has worked fine. Also had to change the ignition computer to a turbo. Many say the standard 240 ignition computer works fine but, in my case, it pinged like crazy.

Also, a resistor pack is one more thing that can go bad. Had it happen on my 740 Turbo and left me stranded with no fuel delivery.
 
An even simpler explanation:

A factory turbo 940 (LH2.4) uses low impedance injectors and a resistor pack. An NA 940/740/240 (also LH2.4) runs no resistor pack, so when you swap over the turbo ECU and injectors you need to add the reistor pack too. Essentially you're just copying the factory turbo setup in your originally NA car.

Hen

Exactly what I thought, but still wanted to ask. Both answers were what I was looking for.

Another thing I see is 940s needing a certain flywheel/flexplate? If you got the junk out of a 2.4 car, won't it have the proper windowed flywheel/flexplate? I kinda want to do this just so I can make a SOLID how to. This thread is great for some info but still leaves me scratching my head.


And fk you guys who say we need to search. If it is so common and so simple, then we shouldn't have to. Something as simple as a parts list should be a breeze. This is a forum. It is a pearl of knowledge. I LOVE how the guys who have NEVER had to search something, say to search. You get conflicting answers and sometimes it isn't specific enough.
 
Exactly what I thought, but still wanted to ask. Both answers were what I was looking for.

Another thing I see is 940s needing a certain flywheel/flexplate? If you got the junk out of a 2.4 car, won't it have the proper windowed flywheel/flexplate? I kinda want to do this just so I can make a SOLID how to. This thread is great for some info but still leaves me scratching my head.


And fk you guys who say we need to search. If it is so common and so simple, then we shouldn't have to. Something as simple as a parts list should be a breeze. This is a forum. It is a pearl of knowledge. I LOVE how the guys who have NEVER had to search something, say to search. You get conflicting answers and sometimes it isn't specific enough.



you get conflicting answers because there's more than one way to accomplish what you're trying to do.

Search. Read. Broaden your own horizons. Even if you don't use someone else's implementation, it doesn't hurt to know what other people are doing. Further more, no one actually owes anyone anything. If something is common knowledge (and a lot of this stuff is; and has been discussed dozens of times and probably mentioned in every single +T thread ) *you* need to be able to sack up and read and then come up with an intelligent question. If you're having trouble figuring out the what's and why's of a +T, I would gently suggest that maybe its not for you.
 

These can also be found on GM cars with the Supercharged 3800 V6:
Buick Park Avenue Ultra
Buick Regal GS / GSX (SLP)
Buick Riviera Supercharged
Chevrolet Impala SS
Chevrolet Monte Carlo SS
Oldsmobile Eighty-Eight LSS (limited)
Pontiac Bonneville SSEi
Pontiac Grand Prix GTP

These injectors are 4-hole instead of pintle style and flow 36lbs/hr with a resistance of 14.8Ω. I grabbed a set of 6 off a Park Avenue Ultra at the junkyard and they look like they'll fit right in, but I'll report back upon installing them. If you want an Eaton M90 you can grab one off one of these cars as well.
 
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you get conflicting answers because there's more than one way to accomplish what you're trying to do.

Search. Read. Broaden your own horizons. Even if you don't use someone else's implementation, it doesn't hurt to know what other people are doing. Further more, no one actually owes anyone anything. If something is common knowledge (and a lot of this stuff is; and has been discussed dozens of times and probably mentioned in every single +T thread ) *you* need to be able to sack up and read and then come up with an intelligent question.

Agreed. Mostly. I am talking about the threads where you read and read but the question is never truly answered, OR the problem isn't your exact issue. I can agree with needing to piece info together. And no, nobody owes anybody info. But when you are on a forum such as this, it is implied/expected to answer questions and help out. No matter how noobish the questions are. Everybody starts somewhere.


If you're having trouble figuring out the what's and why's of a +T, I would gently suggest that maybe its not for you.
Come on man. I hate seeing stuff like that. I am all about anybody trying something new. This forum(mainly you) is built off doing stuff we don't know much about. Like I said, everyone starts somewhere. Doesn't mean they shouldn't do it.
 
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that turbo would have worked, but that's about 3x what I would have ever paid for that setup (not to mention what you'd pay in a junkyard) but whoever sold it is the luckiest man i know. $350 shipped for a 13c with a stock 90+ and an oil feed line? JEEEEEESUS
 
Agreed. Mostly. I am talking about the threads where you read and read but the question is never truly answered, OR the problem isn't your exact issue. I can agree with needing to piece info together. And no, nobody owes anybody info. But when you are on a forum such as this, it is implied/expected to answer questions and help out. No matter how noobish the questions are. Everybody starts somewhere.



Come on man. I hate seeing stuff like that. I am all about anybody trying something new. This forum(mainly you) is built off doing stuff we don't know much about. Like I said, everyone starts somewhere. Doesn't mean they shouldn't do it.

You have been on this board for 5 years.. So instead of crying about the lack of a "list" why don't you make one up? :) I would suggest to break it down by model and year....I hope to see your 1st draft by the end of the week....
 
t-na bottom end

Been ages since ive posted on here but i too did a write up years ago on a 740turbo that i built. So i will give a huge post of my experiences.. I went a waaay different direction in my na-t though.. I had a turbo car(1990 744t) with turbo ecu-i wanted a na block -more compression , more power! I bought a used b230f out of a salvage yard for $100 ,125k on it, used the turbo head (sodium valves.. not really an issue) a supra fuel pump in tank (mk3 turbo) and supra mk3 fuel injectors. I had supra parts laying around everywhere! I bypassed the injector resistor by jumpering it back to itself. I used a radio shack potentiometer on the signal wire from the airmass meter to the ecu and adjusted my airfuel with the potentiometer.. It was a $2.25 air fuel controller, why use safc? Your 02 sensor adjusts for idle and part throttle mode, and the amm takes over when the boost hits the fan.
Anyone who has tuned a car knows that part throttle is usually the most difficult to tune-this is where the lh2.4 shines and adapts amazingly well to large mods-this is already tuned for you thru slowly running your car thru it paces. All i adjusted for(with pot) was for part to wot.Because of the 440 cc supra injectors the hardest part of this whole project was the first initial start up, the o2 sensor wanted to see less injector than what i had in it. It kept flooding it! It took about 10 minutes (no ****) to start the car, then the ecu learned over it and it worked great from there. I bolted a turbo oil return line upside down into the top of the oil pan and used ss hose and a turbo return line gasket (because thats all i had at the time). A friend of mine ,Jack Harris had a shop in Nc and offered to dyno my car when i drove it from Tx to NC and back to Tx. He had questioned the validity of my potentiometer and its relevance to my application. We strapped it up on his dyno (mustang ) at p1 auto (his shop) . I had g-teched it earlier at 327whp , but doubted that ..Even though i pulled my moms vette in Va..So we strapped it up and turned the pot to wide open(hardly any resistance). Car wouldnt rev past 3500 and was waaay rich. Then turned it down to the setting i liked and the airfuel drastically changed. If i remember correctly it made 195 wheel i believe with the turbo falling off and 235 ft pound on a na motor (big rod).
I posted up details of all this maybe 5-8 years ago.Then forgot my password and had to change username.
I noticed on the drive back the car was getting slower and slower, then i saw the turbo was loose. I remember being disappointed at the dyno runs !
I don't know where the heck the post went, i even included the air fuel change on the dyno along with the runs..It works but you have to have a clue as to what you are doing. I always ran 93 octance and when i knew i was gonna beat on it i would add two cans of Berrymans B-12 (it has toluene as main ingredient which was the f1 fuel of choice in turbo era where 91 ci motors in the back of the line where making 1100hp-also used in TNT!) which is also great for cleaning stains off concrete and melting bees!
I haven't seen anyone mention this thru-out this whole thread, so i will make it Known.. If you plan to beat on your car for more than 20 seconds continuously, like say doing a top speed run down a highway with your buddys b-16a bottle fed hatch , for a hour or so on and off, be prepared to pull over and call a tow truck.. You will melt the motor if you stay in it for way too long , and don't ever allow the intercooler and turbo and motor to cool down..Have common sense..I apparently didn't have any , so i learned me some sense! That was my own mistake for melting it but it ran with that same setup for a few years. had i not been a jackass, that motor would still be kicking..
I also used a turbo off of an merkur xr4ti that i found in a salvage yard..After i got back to Tx i put an npr intercooler on it and ran it at Kennedale 1/8th mile track. It ran a 9.0 with a 2.1 60 foot (1 tire fire) and broke the trans on the second boost launch of the night..It was a fun car. I sold it when i left Texas with a 16valve stuffed in it with a regal turbo welded on a fabbed down pipe off the stock exhaust manifold, divorce sucks in the middle of a big project..

Fast forward, Did the same list of mods to a friends 92 940 turbo, BUT -SMALL rod na block w squirters, merkur xr4ti turbo, potentiometer WIThOUT the supra injectors (he never would put them in -i told him the pot is pointless without larger injectors) and he added a huge front mount intercooler to it, i mean it was freakin massive, he cut the front bumper supports out -had to move headlights and all kinds of Nonsense to get this intercooler to fit when i was working at Alamo Autosports. I told him to keep the boost down, so he kept it down for a month,10psi- then cranked it to 20 and beat the living daylights out of this 940, turbo kept comeing loose , intercooler pipes keep blowing off and splitting hoses. But he road raced it at TMS and daily drove the car and was always doing 1/4 mile burnouts with it... Apparently Lucky at Ipd and he, had some great plans for this car-but they didnt pan out due to financial restraints..ANYWAY,That car was amazingly faster than my 740 with comparable mods, less the giant intercooler he had-psi per psi. Plus he was able to run 20 psi w/o hitting fuel cut. i could only run 13-with 15 psi initial spike. Moral of the story is if you go na to turbo, the lh2.4 i think- is most forgiving. That's why i now have a 1993 945 t with a na bottom end in it with smaller rods.. It makes more power pound for pound, but over all may not be able to handle as much power as a thick rod motor -say a b23ft. The volvo red blocks, each one in its own respect is tough as nails. But- tuning, common sense, and preventive maintenance is everything! Anyone can blow up any turbo motor if they keep their foot in it long enough. Keep that in mind!

End short story.

Kris Weldy

My current turbo car orig, with a na bottom end , slotted "A" cam and oversize exhaust Valves that KNox did the headwork on , And Vince Ported.
http://www.facebook.com/kris.d.weldy?v=app_2392950137&ref=profile#!/video/video.php?v=1231631602478
 
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I just recently got a 70,000 mile b230f motor and i am going to convert it into a T.I also have a b230ft that is in my 1990 volvo 740T.So i will be using the cam,injectors and exhaust intake from the b230ft.I was wondering if any1 knows what size hole i should drill on the bottom of the b230f block i can see where the hole goes im just not too sure on the size of the drill bit i should use.Also do you use some type of a rubber grommit that the turbo return line goes into or does it have to be tapped and have a fitting installed.
 
Went +t, and I regret it. I have a B230 with 250 k on it, and I put a 13 C on it. The car drives, but it now smokes incredibly. So much, it's undrivable. It smokes at idle (sometimes more smoke than others) and under acceleration. It's also spitting out ALOT of oil. Could my oil feed be messed up? Is the turbo a goner? Did I plus T a engine with too many miles?

EDIT: Just let it run for maybe 15 minutes, and it only smokes when I let off now.
 
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I just wanted to add this for any one thinking of adding a turbo to a Volvo. It is so easy if you stick to stock at first.

I received my 1988 240 for free. It hadn’t run in years but was in perfect condition otherwise. After a tune up and a trip to the salvage yard, I replaced the fuel system and away we went. We had a hard time adjusting to the raw power of the stock motor so we decided to +T it. So I purchased a cheap ass turbo 1987 760 for scrap basically it was on its way to the salvage yard. I pulled off every part I thought I could use including the AR Garrett which needed a new turbine wheel and a rebuild. It was pretty easy with the help of eBay for the rebuild kit and Will Tillery for the wheel. It’s now as good as new. Well probably not, but it works great now.

We used the computer from the donor along with the intercooler and all the plumbing. Instead of using the green low impedance injectors and splicing in the resistor pack we decided on a set of high impedance new style Bosch red Turbo injectors 0 280 155 831. They are the skinny ones with better spraying 4 hole tips. This set up worked great for me I had absolutely no issue with the injectors and the donor computer along with the donors 3 bar fuel rail. I liked this setup better than more wire splicing.

We used a 90+ exhaust manifold. I cut the 760’s downpipe to fit. It wasn’t much metal that has to be removed but you have to get the angle right. It helps to have two people someone to line it up and someone to figure the cuts and the tack weld to hold it together while you mock it up. I didn’t have time to do the entire exhaust. So we bolted up the finished down pipe which fit like factory. I was even able to use the clamp that holds it to the bell housing. We cut out the cat but unfortunately we temporarily hooked up the stock exhaust to drive it to the exhaust guy for 3” pipe and a flow master I already have. It’s been many months and I haven’t made it in yet. Soon.

I drilled the block. Drilling the pan seemed functional but generic. I did it in place, sort of. We have a 5 speed m47 Standard transmission. We decided to replace the clutch at the same time. So we dropped the transmission unbolted the remaining 2 engine mounts then used an engine hoist to hover it in the engine bay. Doing it this way allowed me to move the engine up or down and side to side just a little but enough that it made the entire project much easier. So I would recommend if you're thinking of turboing your standard Volvo go ahead and hit that clutch at the same time, you’re probably going to need to anyway.

I will stop typing now and just say this if you are mechanically inclined its easy at least on an old Volvo. I spent about a week doing it but I replaced everything. I could do it now in a couple few days as long as all the parts are in order.

This is the only time I would ever utter such words but drill baby drill (your block that is, leave my shores alone I am willing to pay more for gas like every one else around the world. Oops too late, thanks dumb dumbs).
 
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pull the plugs and see if they are fouled...if not you probably are leaking oil from turbo (into exhaust). popped a carbon seal in my last 745 and would fog out at stop lights.
 
Went +t, and I regret it. I have a B230 with 250 k on it, and I put a 13 C on it. The car drives, but it now smokes incredibly. So much, it's undrivable. It smokes at idle (sometimes more smoke than others) and under acceleration. It's also spitting out ALOT of oil. Could my oil feed be messed up? Is the turbo a goner? Did I plus T a engine with too many miles?

EDIT: Just let it run for maybe 15 minutes, and it only smokes when I let off now.

your turbo seals are f%$#@d. pull that 13c and I bet you have some serious shaft play too. Check it soon or it'll look like someone threw rocks into a blender.
had the same issue on my audi a4--tons of smoke but only when I let off and the turbo spools down. if your exhaust permits, listen as the turbo is spooling down. It should start to smoke as soon as the sound of the turbo stops.
 
your turbo seals are f%$#@d. pull that 13c and I bet you have some serious shaft play too. Check it soon or it'll look like someone threw rocks into a blender.
had the same issue on my audi a4--tons of smoke but only when I let off and the turbo spools down. if your exhaust permits, listen as the turbo is spooling down. It should start to smoke as soon as the sound of the turbo stops.

Yeah, got a new 13c, no more smoke. I also got a turbo ECU, but i'm still on NA injectors so it wont start. :grrr:
 
Ok, hopefully I'll find an answer to this, but as I read most everyone has swapped the ignition and fuel computers over directly from a 7 series to a 2 series with no issue. Well when I used my donor ignition computer I got nothing, the car is a '87 745 with a B230FTi, M46 manual. The ignition box from that car is a 0 261 201 012. The computer out of the '91 244 B230F AW71 has a p/n of 0 227 400 169. The boxes have the same plug in's but the turbo box will not run the N/A car in the testing I have been doing before I take apart the 240.

From what I have been looking at the '91 240 with a 5 wire AMM should be LH 2.4, like the '87 745, but when I look at the fuel computers, they use completely different plugs. Which is contradictory to what most of the information in this thread has presented. I'm pretty sure I'm going to have to yank out the wiring harness from the 745 to make this work, unless someone else has a better idea.
 
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