Building a 2270 motor with LH-Jet, A discussion thread.... Options

[boxsterfan]

First off, I am not anywhere near an expert in engine building, cam selection (how duration and lift affect the motor at idle and driving), injector flow rates, etc, etc, etc... So now that I have that out of the way, I still want to figure out the bits and parts that ***may*** make it possible to run a 2270 motor with LH-Jet. The primary reasons I am looking at this setup are because:

• L-Jet likely is not a good setup for this based upon my reading (issues with cam, idle troubles, hesitation, full power, etc...).
• I don't want to run carbs.
• I don't believe I want to tackle MegaSquirt (leaving the door open though).
• It sounds like fun/dare to be different.

1. The first question that comes to mind is will it be LH-Jet 1.0 vs LH-Jet 2.0?
From my research, LH-Jet 1.0 was pretty rare and used in the early 80's but then a switch to LH-Jet 2.0 occured. The primary difference between the two was that LH-Jet 2.0 utilized a Throttle Position Sensor (TPS) whereas LH-Jet 1.0 did not.

2. If LH-Jet 2.0 variant is the desired setup, which sub-variant would be used?
There appears to be a couple sub-variants within LH-Jet 2.0 primarily consisting of LH-Jet 2.2 and LH-Jet 2.4. It appears one of the primary differences between the two is that the LH-Jet 2.4 utilizes a "trigger flywheel" and the LH-Jet 2.2 does not. What exactly a "trigger flywheel" is I am not sure....I am guess that this is a notch or mark on the flywheel that is monitored by a sensor with the data fed back to the ECU.

3. What would the "build" sheet look like for such a setup?

Of course, this list can get complicated, but the desired build here is a street car with spirited driving. I would want excellent low-end torque, around 140-150HP on the motor and good pull all the way through the RPM range up to XXXX RPM (not sure where redline would be). Note also, the car will remain as a narrow body with 4-lug wheels.

• 2270 motor with which CAM?
• What plenum could work here?
• What intake runners would work here?
• Which fuel injectors could work here?
• Need to upgrade fuel pump?
• ECU - need to pull from Volvo/Saab from 80's
• FI Wiring Harness - need to pull from Volvo/Saab from 80's and will require customization
• Need any relay boards?
• Hot-wire MAF Sensor - need to pull from Volvo/Saab LH-Jet system
• IAC - Electronic Idle Controller - need to pull from Volvo/Saab from 80's
• O2 Sensor - need to pull from Volvo/Saab from the 80's - where to mount?
• CHTS - Utilize the existing CHTS (TS2) input into the ECU as a substitute for the coolant temp sensor (just have to figure out the proper resistance)
• Cold Start Valve - probably not needed here in the Bay, but what could be done here? Or does existing on the Type IV motor work here?

Of course, if you have already done this setup, it would be great to here from you, how the car drives, pain points, etc, etc....

[Mark Henry]

No clue and you are trail blazing here, looks like a volvo or 928 FI system.

One of the best places to ask/rescerch in a aircooled app
http://www.shoptalkforums.com/viewtopic.php?t=34970


Good luck

[Dave_Darling]

Your best bet is to find a four-cylinder car that had about a 2.3L displacement and made about 150 HP that ran LH-jet. Then just use all the parts from it that you can.

My guess is you'll have to actually use something from a larger displacement motor than 2270cc, because I don't think there were a lot of 2.3L motors back when LH-jet was popular that made as much as 150 HP... Especially four-bangers.

Cam, heads, intake, and exhaust all have to work together.

I'm thinking you may be able to use the stock 2.0 manifold and such, but you'll have to make mods to fit the parts from the donor car--like injectors.

A header of some kind is probably the best idea for exhaust. Ideally, use a Tangerine piece. But any header setup will have a collector that will (eventually) get gases from all four exhaust ports, so that's a good place to put your O2 sensor.

The relay board in an L-jet 914 is mostly there to hold the voltage regulator and to attach the main wiring harness to the FI wiring harness and engine wiring harness. The actual FI relays are elsewhere, generally hanging off the battery tray. You can follow that model pretty easily if you choose.

Use the fuel pump from your donor car, or double-check the required volume and pressure for the donor car's pump. And get a pump that meets or exceeds those. (The stock 914 pump might be that pump, or you might need to get something like a Walbro pump.)

Sounds like an interesting project, that's for sure!

User ejm (Ed, who works for Racer Chris) put a CIS setup on his 1.8 turbo; I think some of the challenges in that would be similar to the ones you will be facing. So he may have some good input on that.

--DD

[ClayPerrine]

Use LH-Jet 2.2 so you don't have to get involved with trying to duplicate the notches/pins in the flywheel.

Use the 2.0 L intake runners, plenum and throttle body. Better yet would be a 912-E throttle body. If you use the 2.0L throttle body, you have to make mounts for the TPS. The 912-E throttle body will have a better mount.

Use everything you can from the LH-Jet system.

Mount the O2 sensor where all 4 pipes come together. It might be better to use a heated O2 sensor, just wire the heater circuit to the same power source as the ECU.

[r_towle]

Your best bet is to find a four-cylinder car that had about a 2.3L displacement and made about 150 HP that ran LH-jet. Then just use all the parts from it that you can.


--DD

Agreed on that.

The big difference between L-jet and LH-jet is the O2 sensor with a feedback loop for constant monitoring of the mixture.

Look at the 924/944 motors, I cannot remember the sizes, but those systems may work, and have support in the aftermarket.

The other one is VW (rabiit/golf/jetta etc) which has a large aftermarket support community.

Rich

[boxsterfan]

Use LH-Jet 2.2 so you don't have to get involved with trying to duplicate the notches/pins in the flywheel.

Use the 2.0 L intake runners, plenum and throttle body. Better yet would be a 912-E throttle body. If you use the 2.0L throttle body, you have to make mounts for the TPS. The 912-E throttle body will have a better mount.

Use everything you can from the LH-Jet system.

Mount the O2 sensor where all 4 pipes come together. It might be better to use a heated O2 sensor, just wire the heater circuit to the same power source as the ECU.

Clay, thanks for the feedback (as you also put info in another thread that got me thinking about this whole concept/project).

How about my distributor and electronic ignition? Do I get to use what I have or do I need to grab those parts also?

[boxsterfan]

Your best bet is to find a four-cylinder car that had about a 2.3L displacement and made about 150 HP that ran LH-jet. Then just use all the parts from it that you can.


--DD

Agreed on that.

The big difference between L-jet and LH-jet is the O2 sensor with a feedback loop for constant monitoring of the mixture.

Look at the 924/944 motors, I cannot remember the sizes, but those systems may work, and have support in the aftermarket.

The other one is VW (rabiit/golf/jetta etc) which has a large aftermarket support community.

Rich

The O2 sensor is a difference but also the air flow meter is a "hot wire" unit vs. the barn-door L-Jet AFM's.

There are definitely 4-cylinder NA Volvo's running around 150-160 HP (B230FT motor for example).

[r_towle]

Your best bet is to find a four-cylinder car that had about a 2.3L displacement and made about 150 HP that ran LH-jet. Then just use all the parts from it that you can.


--DD

Agreed on that.

The big difference between L-jet and LH-jet is the O2 sensor with a feedback loop for constant monitoring of the mixture.

Look at the 924/944 motors, I cannot remember the sizes, but those systems may work, and have support in the aftermarket.

The other one is VW (rabiit/golf/jetta etc) which has a large aftermarket support community.

Rich

The O2 sensor is a difference but also the air flow meter is a "hot wire" unit vs. the barn-door L-Jet AFM's.

There are definitely 4-cylinder NA Volvo's running around 150-160 HP (B230FT motor for example).

Possibly, but early LH-jet was just another barn door item..
I believe the 924 and 944 are barn door AFM units.

In reality, they are measuring air volume, not air pressure...

If you find a motor that is the same size with the same output, you will be much farther ahead.
Just look for an ECU that someone understands how to flash....the really early stuff cannot be flashed, but the mid 80,s on up can be modified...sometimes.

Volvo (in my experience) would honestly require you to speak swedish if you want to tune it...there is some support in the US, but the real decent knowledge is overseas.

I would look at BMW, VW/audi, or Porsche, they all seem to have tuners out there.

[ClayPerrine]

The 924 is CIS (Had one). The 944 is motronic with a Vane air meter. If you found a replacement for the vane air meter that was a hot wire MAF (they sell them for the Motronic 3.2 911 engines), then it would work with the big 4 in a 914. But the motronic fuel and ignition map would be all wrong for a Type-IV.

[2mAn]

E30 M3 & MB 2.3-16 are both in the realm of what you are looking for (displacement & powerwise), though I'd recommend getting a motronic setup from a M42 powered 318 and doing the MAF conversion avaliable through Miller. Its a tunable setup through a laptop. just my .02

you could also get an EFI setup from a naturally aspirated subaru motor, at least that will come from a flat motor vs an inline.

[edwin]

Why bother trying to adapt something that has been setup for a completely different engine rather than use and aftermarket ecu which gives heaps of flexibility.
I just removed the lh2.2 setup from my '90 Saab 900 because it had its limitations on the engine it had been setup for. Can't think what it will be like getting it going on another engine. I went haltech and haven't looked back
Lh2.2 in the forms I've seen has been batch fired and dissy ignition which isn't that special. Lh2.4 can do coil packs and I think 2 injectors but you'll need the crank trigger
Saab 9000's came in 2.3L with lh2.4
Cheers
Edwin

[boxsterfan]

According to my productive day at "work", the LH2.2 ECU's are programmable as are the LH 2.4's. The LH 2.2 setup is seeming pretty straight forward, but I am certainly not aware of all the math that has to take place to make the motor run well.

[colingreene]

Honestly Id probably tackle doing a mega squirt and go from there.
its a pretty well covered topic with lots of support and you have the benefit of having others to help you trouble shoot it.
Plus its more modern than a band aide solution.
Id still use a pair of carbs as air bodies though.

[boxsterfan]

Honestly Id probably tackle doing a mega squirt and go from there.
its a pretty well covered topic with lots of support and you have the benefit of having others to help you trouble shoot it.
Plus its more modern than a band aide solution.
Id still use a pair of carbs as air bodies though.

I'm leaving that (MegaSquirt) on the table, but I do want to take a serious look at the LH-Jet 2.2 setup. The ECU can be programmed. Enthusiasts have various fuel maps out there. The parts should be cheap, a plethora of them and many available at your local PnP.

Probably the two biggest pains so far are working on the wiring harness and getting an O2 sensor installed at the exhaust (not sure where I would even do this on a SS Heat Exchange setup with Triad exhaust. Probably just pick one side of the exhaust to monitor....cylinders 3 & 4 exhaust).

[sportlicherFahrer]

On the muffler itself you should be able to get a good O2 reading from the pipe that goes up to the split from the bottom can. all 4 cylinders have to feed through that one spot. Think I saw a muffler at Dave's that had a bung there...

[jcd914]

On mine the O2 sensor is in the Triad muffler, rather than messing with either of the SSIs.

Jim

[AndyB]

First off, I am not anywhere near an expert in engine building, cam selection (how duration and lift affect the motor at idle and driving), injector flow rates, etc, etc, etc... So now that I have that out of the way, I still want to figure out the bits and parts that ***may*** make it possible to run a 2270 motor with LH-Jet. The primary reasons I am looking at this setup are because:

• L-Jet likely is not a good setup for this based upon my reading (issues with cam, idle troubles, hesitation, full power, etc...).
• I don't want to run carbs.
• I don't believe I want to tackle MegaSquirt (leaving the door open though).
• It sounds like fun/dare to be different.

1. The first question that comes to mind is will it be LH-Jet 1.0 vs LH-Jet 2.0?
From my research, LH-Jet 1.0 was pretty rare and used in the early 80's but then a switch to LH-Jet 2.0 occured. The primary difference between the two was that LH-Jet 2.0 utilized a Throttle Position Sensor (TPS) whereas LH-Jet 1.0 did not.

2. If LH-Jet 2.0 variant is the desired setup, which sub-variant would be used?
There appears to be a couple sub-variants within LH-Jet 2.0 primarily consisting of LH-Jet 2.2 and LH-Jet 2.4. It appears one of the primary differences between the two is that the LH-Jet 2.4 utilizes a "trigger flywheel" and the LH-Jet 2.2 does not. What exactly a "trigger flywheel" is I am not sure....I am guess that this is a notch or mark on the flywheel that is monitored by a sensor with the data fed back to the ECU.

3. What would the "build" sheet look like for such a setup?

Of course, this list can get complicated, but the desired build here is a street car with spirited driving. I would want excellent low-end torque, around 140-150HP on the motor and good pull all the way through the RPM range up to XXXX RPM (not sure where redline would be). Note also, the car will remain as a narrow body with 4-lug wheels.

• 2270 motor with which CAM?
• What plenum could work here?
• What intake runners would work here?
• Which fuel injectors could work here?
• Need to upgrade fuel pump?
• ECU - need to pull from Volvo/Saab from 80's
• FI Wiring Harness - need to pull from Volvo/Saab from 80's and will require customization
• Need any relay boards?
• Hot-wire MAF Sensor - need to pull from Volvo/Saab LH-Jet system
• IAC - Electronic Idle Controller - need to pull from Volvo/Saab from 80's
• O2 Sensor - need to pull from Volvo/Saab from the 80's - where to mount?
• CHTS - Utilize the existing CHTS (TS2) input into the ECU as a substitute for the coolant temp sensor (just have to figure out the proper resistance)
• Cold Start Valve - probably not needed here in the Bay, but what could be done here? Or does existing on the Type IV motor work here?

Of course, if you have already done this setup, it would be great to here from you, how the car drives, pain points, etc, etc....

I am running L-Jet with a 2.2 I don't know where you have been reading but I have no issues with my fuel system or the car. It was a 75 1.8l

[0396]

Interesting read. .subscribed

[boxsterfan]

First off, I am not anywhere near an expert in engine building, cam selection (how duration and lift affect the motor at idle and driving), injector flow rates, etc, etc, etc... So now that I have that out of the way, I still want to figure out the bits and parts that ***may*** make it possible to run a 2270 motor with LH-Jet. The primary reasons I am looking at this setup are because:

• L-Jet likely is not a good setup for this based upon my reading (issues with cam, idle troubles, hesitation, full power, etc...).
• I don't want to run carbs.
• I don't believe I want to tackle MegaSquirt (leaving the door open though).
• It sounds like fun/dare to be different.

1. The first question that comes to mind is will it be LH-Jet 1.0 vs LH-Jet 2.0?
From my research, LH-Jet 1.0 was pretty rare and used in the early 80's but then a switch to LH-Jet 2.0 occured. The primary difference between the two was that LH-Jet 2.0 utilized a Throttle Position Sensor (TPS) whereas LH-Jet 1.0 did not.

2. If LH-Jet 2.0 variant is the desired setup, which sub-variant would be used?
There appears to be a couple sub-variants within LH-Jet 2.0 primarily consisting of LH-Jet 2.2 and LH-Jet 2.4. It appears one of the primary differences between the two is that the LH-Jet 2.4 utilizes a "trigger flywheel" and the LH-Jet 2.2 does not. What exactly a "trigger flywheel" is I am not sure....I am guess that this is a notch or mark on the flywheel that is monitored by a sensor with the data fed back to the ECU.

3. What would the "build" sheet look like for such a setup?

Of course, this list can get complicated, but the desired build here is a street car with spirited driving. I would want excellent low-end torque, around 140-150HP on the motor and good pull all the way through the RPM range up to XXXX RPM (not sure where redline would be). Note also, the car will remain as a narrow body with 4-lug wheels.

• 2270 motor with which CAM?
• What plenum could work here?
• What intake runners would work here?
• Which fuel injectors could work here?
• Need to upgrade fuel pump?
• ECU - need to pull from Volvo/Saab from 80's
• FI Wiring Harness - need to pull from Volvo/Saab from 80's and will require customization
• Need any relay boards?
• Hot-wire MAF Sensor - need to pull from Volvo/Saab LH-Jet system
• IAC - Electronic Idle Controller - need to pull from Volvo/Saab from 80's
• O2 Sensor - need to pull from Volvo/Saab from the 80's - where to mount?
• CHTS - Utilize the existing CHTS (TS2) input into the ECU as a substitute for the coolant temp sensor (just have to figure out the proper resistance)
• Cold Start Valve - probably not needed here in the Bay, but what could be done here? Or does existing on the Type IV motor work here?

Of course, if you have already done this setup, it would be great to here from you, how the car drives, pain points, etc, etc....

I am running L-Jet with a 2.2 I don't know where you have been reading but I have no issues with my fuel system or the car. It was a 75 1.8l

Can you describe the characteristics of your car (HP, Torque, intake, exhaust,etc...) and it runs throughout the RPM range? Street or track? Idles well? Anything you would change?

[Rand]

I can't help but wonder about the Megasquirt (or even Microsquirt) thing. You are looking at doing something that hasn't been done much, vs what has - and has been proven. It sounds like you think MS is complicated and you are afraid of it, when it seems to me it is simple and proven?

But I love it that you are looking at something new. Always love to see that. Look forward to hearing what you end up with.