Converting K-jet to LH 2.4 (Turbo)

[turbobrick211]

Okay, so I would like to try converting my "82 244 turbo over to LH 2.4 system, and would like to know which parts I will need to do the full swap. Here is my list so far, let me know if I am missing anything.

b230 manifold
b230 throttle body with TPS
fuel injectors and fuel rail
FPR
Coolant temp sensor
ECU (not sure about number yet)
Wiring harness
Air mass meter
Resistor pack
Fuel lines from pump to fuel rail
Oxy sensor

I have already changed over to the later style b230 intake manifold and TB, so no big deal there. I also already have the injectors and fuel rail in place, to plug the holes. I am not sure if there were different TPS's depending on which car it was on, so this is still in question. I have been running 20+ psi boost with the K-jet system, so I will need to make sure I don't have fuel cut because of high boost. Also, the motor is tuned to make power well above 5500 rpm, so rev limiting will need to be removed/modified.

My main question, other than if I have a complete list of all the parts I will need, is which ECU number should I look for that will work best in my application? And what year an model would I find such an ECU?
Any and all help would be greatly appreciated. I plan on doing the install in a very repeatable fashion, and document everything that I do so that other K-jet folks can do the same upgrade with ease.

Thanks,
Eric

[ereuter]

Eric-
Why not do Megasquirt or some other programmable EFI system instead of LH? It sounds like you are doing a lot of performance tuning, and that would give you a lot more flexiblity without having to tune with patches and workarounds.

Eric

[turbobrick211]

The reason I am not going with MegaSquirt at this time, is because I would like to get the car setup on an EFI setup first. From there, I am going to use a Unichip to program everything, including ignition. The Unichip is similar to Megasquirt, except it has many more variables, and can run more outputs. It is for a project that I am working on for my work. Megasquirt is great, but Unichip is better. And, it will not cost me as much. AND, I would really like to see how the LH 2.4 system runs my current motor.


Eric

[945ti]

What of the ignition side?
OBD1?
The wiring harness, amm adn all that crap were not meant to be an a 240, so it may take a little reinventing the wheel to get it all in there.
Also, you left out one piece that will totally throw you for a loop. You need a new flywheel +crank position sensor, and probably clutch, because I am guessing you have the 8.5" clutch, which will not work with LH2.4. You can get said flywheel from plenty of cars for a reasonable sum, but you are stuck with the 9" heavy flywheel, however, on the up side, you can use a softer (more progressively engaging) clutch to effectively hold more power with it.
Radio spression relay, is probably something you probably want.
You will want LH2.4 probably from a car with a cold start injector (can't remember the ECU #).
Many 92+ ECUs have an output to trigger the electric fan, you can decide if you want to wire up that output or not, however, that could be additional headache.

Some ECUs appearently have very slightly different AMM cut voltages, but they all seem to supply about the same total amount of fuel.

[NoSloVo]

I did this to one of my 242s.

go to a volvo shop and ask to photo copy the wire diagrams from say a 94 940T as well as the diagrams from a 90 244 (lh 2.4).... and even the 83 240 turbo.

you can use the same fuel pump and ust fit up a line to the fuel rail or go with thte complete 90 240 setup.

get the wire harness intemediate shaft distributor and flywheel (60-2) from the 90 240
get the computers airmass injectors and resistor pack form the 94 940T

compare the two diagrrams carfully and figure out where you need to change wire pin positions (I dont think there were more than two .. they might also be ok) for the computers. you probably should also draw your own diagram so you have it for later. I had to run two fuelpump relays

you'll need to splice in the resistor pack for the injectors and elongate the airmass plug wires to the other side of the car.

Car runs great set up with this setup ... though stock it has a rev limiter at about 6000 and youll be on it all the time unless you can get a chip somewhere.

have fun!

[turbobrick211]

What of the ignition side?
OBD1?
The wiring harness, amm adn all that crap were not meant to be an a 240, so it may take a little reinventing the wheel to get it all in there.
Also, you left out one piece that will totally throw you for a loop. You need a new flywheel +crank position sensor, and probably clutch, because I am guessing you have the 8.5" clutch, which will not work with LH2.4. You can get said flywheel from plenty of cars for a reasonable sum, but you are stuck with the 9" heavy flywheel, however, on the up side, you can use a softer (more progressively engaging) clutch to effectively hold more power with it.
Radio spression relay, is probably something you probably want.
You will want LH2.4 probably from a car with a cold start injector (can't remember the ECU #).
Many 92+ ECUs have an output to trigger the electric fan, you can decide if you want to wire up that output or not, however, that could be additional headache.

Some ECUs appearently have very slightly different AMM cut voltages, but they all seem to supply about the same total amount of fuel.
Okay, so how about LH 2.2? I don't think it has the crank sensor. I could probably run just the fuel side of the system, and use the 240T ignition system, couldn't I? Is there an ECU number for 2.2 that is better than others? What year of 740 turbo should I look for?

Thanks,
Eric

[945ti]

I think the LH2.2 turbo ECU is dubbed 541, I am not 100% positive though...
can you run the K-jet bosch ignition side? Probably not unfortunately, which probably hits you a bit hard as you have been modding the ignition retard on your 240.
The LH ignition (EZK) uses a hall effect sensor in the dizzy the K-jet 240T uses one like a GM dist (forgetting the technical term at present).
Basically, Lh still needs some RPM signal , and as I recall that is something the ignition and injection share and it has to be recognised by both.
A possible setup that might work for you is running Lh2.2 with a turbo computer, then hacking the mopar ignition found on many NA B23 240s to do boost retard, which I think it will do, it just has a check valve in the way as I recall.
Basically, you could find an ~83 240 B23 (or 85 240 B230 I guess) and take all the LH stuff an wiring, then find a 740T and rob it of the resistors, fuel computer, FPR, and AMM (fuel rail too probably for the 740T style FPR). That might be one relativey simple and 240 friendly way to do it, though I have no idea of the chipping capabilities of the LH2.2 computer.
Lh2.4 could be done, and if you want to do teh flywheel and all that stuff and run a chip to mess with the ignition and rev limit, it seems as though can, but there is a bit mroe stuff involved that what is on your original list.
Edit, I jsut realized that the 83 240 uses LH2.0, might want to find an 85 240 for LH2.2.
84' 760T uses Lh2.0 turbo, so that would be compatable with an 83 240, 85-89 uses Lh2.2 turbo, 541 ECU afaik, though I don't know if some had things like cold start injectors and others didn't.

[linuxman51]

i was going to jump in here and suggest lh 2.2, but it appears someone else already has..

really and truely, if you get the pinouts for the two ecus and the three wiring harnesses from an 88 or so 700 series (less chance of harness rot), nab a distro from a 2.2 200 series, and spice the needed wires in, most of the gauges should stay functional as on the kjet cars they're ecu independant.

and with 2.2 you have a degree of adjustability, and its a bit easier to go from 2.2 to ms if you wanted to at a later date (ms n s can't do anything with the multitooth wheel on 2.4 :( )

[turbobrick211]

i was going to jump in here and suggest lh 2.2, but it appears someone else already has..

really and truely, if you get the pinouts for the two ecus and the three wiring harnesses from an 88 or so 700 series (less chance of harness rot), nab a distro from a 2.2 200 series, and spice the needed wires in, most of the gauges should stay functional as on the kjet cars they're ecu independant.

and with 2.2 you have a degree of adjustability, and its a bit easier to go from 2.2 to ms if you wanted to at a later date (ms n s can't do anything with the multitooth wheel on 2.4 :( )
Hey linuxman51, if I could ask some questions...

when you say "get the pinouts for the two ecus, and three wiring harnesses..." what do you mean by pinouts? And you must be talking about the fuel and ignition ecus? And the wiring harnesses, there is one from LH ecu through firewall, one from there to injectors, and one for ignition? And when I am grabbing the distributor from a 2.2 240, will this be able to have a boost retard function like my 240T dist.? Then, you said to splice the wires in to get the gauges to work... will the gauges have to get their signals from the ecu, and not the sensors?

What if I wanted to only use the fuel portion of LH 2.2? Could I strip away the ignition side of the wiring harness, and only run the fuel side of the box? Could I still use the 240T ignition system?

I would like to do this swap over to 2.2, but I am not sure which parts to look for. I found a LH 2.2 ecu #518 in a 760T, will this work? Or is the 541 the best box to look for? Also, is there a pretty wide range of injectors that will work with this 541 ecu, or do I need to use the ones that came on the same car?

Thanks for any help you can provide. My end goal is two fold. First, I would like to be converted to EFI so that I can eventually change over to MSnS, and not have to fuss with the fuel system change at the same time. And secondly, I would like to see if I can get the Unichip to control LH 2.2. We shall see.

[Morten VJ]

I don't get it.
First you wuold conwert to LH 2.2 and unichip it, to get the fuelside ok.
And then MSnS it to get the spark side of it.
WHY do you want to do that ???
Its mutch easier and cheeper to MS it with your original distributor, and when the fuel side is ok, you can implement the spark side.
This is the way i dit it and i'm still tuning, but its fun.

Morten

[kyle242gt]

Just to chime in here, I'm going from Kjet to MS, then MSnS. I'll have the stock ignition running with MS long enough to get things sorted out, then "deploying" the nS side of things. I think you're asking for a ton of heartache and expense to install 2.2 first. Lots of wires will not be needed with MS (AMM for one).

Just my 2c

[ZVOLV]

Go with 2.2. With 2.4 you are limited to one type of flywheel- bad cant change the ignition timing- bad and get MAF based fuel cut- bad. (overboost switch is easier to bypass)

I can get you whatever parts you need so let me know if you need some cheap parts.