LH injection system variences, 2.2 vs. 2.4 (2024)

I'm pretty confused about the various types of LH fuel injection systems. I'm preparing to swap in a b230ft in my 79 k-jet car; just want to get all the facts first. The plan was to swap in a late b230ft with oil squirters, which, I believe are LH 2.4.

So what's the difference between lh 2.2 and. 2.4...any others I don't know about? Also, will I need a speed tone ring in my diff for all of these?

Up to 88 came with LH2.2
89 and up was 2.4

2.2 doesn't need speedo signal. 2.4 does.

gross polluter said:

Up to 88 came with LH2.2
89 and up was 2.4

2.2 doesn't need speedo signal. 2.4 does.

Click to expand...

Kk, this is a good start. What toes a lh 2.4 do that lh 2.2 doesn't?

Mylesofsmyles said:

Kk, this is a good start. What toes a lh 2.4 do that lh 2.2 doesn't?

Click to expand...

2.4 has computer controlled ignition timing, idle speed, and mixture control. Better for passing smog and dont need any equipment to dial in things like idle mixture or ign timing. . You really should have a timing light though. You can also install bigger injectors and your computer will adjust for them

I strongly suggest LH2.4. I think the only reason people go 2.2 is because they are too lazy to pull the tranny and swap in the necessary flywheel.

all you wanted to know and more..

LH2.2 would be easier to implement overall, vs 2.4. I say overall, as LH2.2 would take a NA 2.2 engine harness, with a 740 EZK ignition harness tied into it. The 2.4 engine/ecu harness is integrated together for the 240 series.

However, in order for LH2.4 to function correctly, you will need a donor rear end with tone ring gear, electronic speedometer too. LH2.4 will run without this, if you don't mind erratic idle, and check engine code stored for no VSS signal.

Which runs better? LH2.4 is a bit more efficient than 2.2, but 2.2 runs just as well.. It just all comes down to what you are looking for really. I just do LH2.2 / EZK on my conversions here.. 2.4 literally takes an entire late model 240 donor car or lots of pnp $$$ to get the parts together.

So, just because you are seeking out a "squirter block", doesn't mean you have to run LH2.4 on it.

gross polluter said:

Up to 88 came with LH2.2
89 and up was 2.4

Click to expand...

For NA.

For turbo, they were LH2.2 up to 89, and LH2.4 from 90+.

fisky52688 said:

Try to get a 91+ donor

Click to expand...

Those should be the lh 2.4 cars...k, gonna need the engine harness or complete car harness? I can snag the axle and hopefully an m47. I can get the bigger strut hubs for big brakes and the gucci heater and a/c system

Some benefits:

Just need the engine harness.

1987+ 240s have vented front rotors and the manual cars have the M47
1988+ have LH2.4 and EZK ignition systems
1990+ have better thrust bearings, valve springs and the stronger connecting rods in the engine.
1993 was the best year of air conditioning for 240, most previous versions suck, and also has round tooth timing gears for longer belt life.
Don't know if you want ABS or not, but some 240s came with it. I think it sucks.

I think the only reason people go 2.2 is because they are too lazy to pull the tranny and swap in the necessary flywheel.

Click to expand...

That's just one reason. Another is to use LH 2.2 to get the car on the road until you can get Megasquirt.

ElPiloto said:

That's just one reason. Another is to use LH 2.2 to get the car on the road until you can get Megasquirt.

Click to expand...

well, i just drove an 87 740 turbo home for the swap...lh2.2, right? let the games begin...still need someone to hold my hand on this.

Personally I feel it's a good call to do 2.2. 2.4 is 2x more painful and still leaves you with a stock setup. MS is just a harness away

The only thing you're gonna be missing from the 740 is the block mounted distributor. If you're swapping the motor, you're [probably] going to need to pull the auxillary shaft and swap it from your 240's motor. The 7/9 series cars generally don't have the gear machined into the shaft to drive the distributor and the head-mounted distributor will interfere with the firewall. I'd bet the chances are lower that a turbo motor would have the correct shaft due to the fact that 240s never got turbo motors.

The engine harness will also be different due to accessory location. If you aren't going to have ac or power steering, it's super-easy to keep the alternator in the 740 position.

MrBill said:

Personally I feel it's a good call to do 2.2. 2.4 is 2x more painful and still leaves you with a stock setup. MS is just a harness away

The only thing you're gonna be missing from the 740 is the block mounted distributor. If you're swapping the motor, you're [probably] going to need to pull the auxillary shaft and swap it from your 240's motor. The 7/9 series cars generally don't have the gear machined into the shaft to drive the distributor and the head-mounted distributor will interfere with the firewall. I'd bet the chances are lower that a turbo motor would have the correct shaft due to the fact that 240s never got turbo motors.

The engine harness will also be different due to accessory location. If you aren't going to have ac or power steering, it's super-easy to keep the alternator in the 740 position.

Click to expand...

MS is money...and I don't have that. As for your comment about the head mounted dizzy...I've heard this...but it's pretty straight forward to convert that to a block mount, no?

I guess I'm just going to have to trace the leads back from the motor, through the firewall... I've got a perfectly good LH setup...lemmie use this and just get the swap done.

Straight forward as pulling the freeze plug where the dizzy should go and looking to see if there is a gear there.

If not - pull front timing cover and swap the shafts. Beware under the oil separator thing is the oil pump drive gear that needs to be removed prior to removing the shaft.

the shaft is just like a pushrod cam. Just sorta let it slide in and be careful going through the bearing areas. I did it with the motor our of the car, easy++

MrBill said:

Straight forward as pulling the freeze plug where the dizzy should go and looking to see if there is a gear there.

If not - pull front timing cover and swap the shafts. Beware under the oil separator thing is the oil pump drive gear that needs to be removed prior to removing the shaft.

the shaft is just like a pushrod cam. Just sorta let it slide in and be careful going through the bearing areas. I did it with the motor our of the car, easy++

Click to expand...

Between that, the block mounted dizzy and the 240 harness, sounds like another trip to the pnp.

I think I'm going to have to find someone local to walk me through swapping the shaft...i'z never takin no motor apart