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Brainstorming a +T with LH 3.1

spe1983

Active member
Joined
Oct 25, 2004
Location
Tulsa, OK
I have bene having fun with my N/A motor in my 90/ 240 DL, and i want to play with my engine. So, a turbocharger provides such fun, and it seems to me that the 3.1 system may not be able be turbocharged... or am i wrong??? And how difficult would changing computers be, or other options. Just curious how difficult the additions will be, thanks you guys. This board makes my day everyday.

-spencer
 
james, parkgh34 was gathering parts to do this on his '92 244 (car is mint, btw) i havent heard from him in a few weeks tho, ill try to get him to update things, or light a fire so he gets started on it
 
A 3.1 car would be a pita to turbo imo in that there were never any turbo 3.1 cars to my knowledge, so there is no computer to swap in that is pre-mapped for larger injectors.

It's too bad because at a glance at least 3.1 seems to be a far more sophisticated management system relative to 2.4 and below. Wether that is the casse or not in practice I don't know. Your coices are basically either try modding the maf ouput or go to a programmable standalone ala MS.

Would be neat to see a +t 3.1 car though!
 
Captain Bondo said:
A 3.1 car would be a pita to turbo imo in that there were never any turbo 3.1 cars to my knowledge, so there is no computer to swap in that is pre-mapped for larger injectors.

It's too bad because at a glance at least 3.1 seems to be a far more sophisticated management system relative to 2.4 and below. Wether that is the casse or not in practice I don't know. Your coices are basically either try modding the maf ouput or go to a programmable standalone ala MS.

Would be neat to see a +t 3.1 car though!

or search teh web there are companies ort there that will remap yoru ecu to yoru specs according to your mods my friedn was gonna do this that is how i nkow but i don't car eto reasearch it since its a one time deal and have to remap when you upgrade parts to work right again
 
Your car is a 90 M47 car right? I think 3.1 started in 91 manual 240 NAs, but it is possible that your 90 has it. Anyway, the flywheel for my car came out of a 91 240 NA LH3.1 I am almost positive, and it works just the same as the OEM turbo LH2.4 flywheel. I also think the connectors and pinouts to the ECU for 2.4 and 3.1 are pretty much the same. This means that you ought to be able to swap to the LH2.4 turbo ECU, AMM (hot wire for 2.4 instead of film type for 3.1), and LH2.4 TPS +greentop injectors and resistors. There wll be some veriations on this theme if the LH2.4 ECU has the cold start or EGR stuff, and whether your 3.1 ECU is designed to deal with that stuff, but it seems worth a try to atleast try and plug in any 2.4 ECU + 2.4 hardware and see where the pinouts lead and what it does. Or, you could just not bother messing with LH2.4 stuff. THe 3.1 seems like it was more sophisticated, being that it had a switched and variable resistor TPS if I remember right. That is a setup much more akin to the hardware you find on the motronic stuff in 850s than 740Ts per se. 3.1 turbo would be a cool experiment, though I am really not sure how heavily 3.1 leans on the TPS reading. I know it must lean on it some because the film type AMM responds slower, but I am not really sure if you would drive normally or badly with a turbo. It could be cool to see where it leans out to maybe run a piggyback on your NA 3.1 system.
 
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Okay- Mikey has two 245's, a '90 and a '93 . Both have AMM with #'s ending in 016. I thought this was lh2.4- how else can you tell? It seems the info on id of 2.4 & 3.1 is sketchy.
He is doing f+t on the '90 in about two weeks. I hope they're not 3.1. We have lh2.4 turbo ecu- a 563 and will install that if possible, plus turbo ignition ecu. Are you saying the pinouts are the same on 3.1?

I have the pinout diagrams for 2.4 and 2.4 turbo, so I know they are the same.
Help!
 
jord9308 said:
Okay- Mikey has two 245's, a '90 and a '93 . Both have AMM with #'s ending in 016. I thought this was lh2.4- how else can you tell? It seems the info on id of 2.4 & 3.1 is sketchy.
He is doing f+t on the '90 in about two weeks. I hope they're not 3.1. We have lh2.4 turbo ecu- a 563 and will install that if possible, plus turbo ignition ecu. Are you saying the pinouts are the same on 3.1?

I have the pinout diagrams for 2.4 and 2.4 turbo, so I know they are the same.
Help!
Yes to my knowledge the pinouts are the same between 3.1 and 2.4, but you need to change the AMM and TPS I think. Is the 93 a stick or auto? If it is an auto it is LH2.4, or atleast every 92 auto I saw was 2.4 and I think I saw a 93 auto LH2.4. Even a 90 stick car should be 2.4. IF the AMM ends in 016 it is 2.4. 3.1 uses a totally different AMM type that should look completely different from 2.4. To my knowledge the only cars that should for sure have 3.1 are 91-93 240 manual trans cars. Volvoman37's F+T M47 manual car was 2.4 and a 90, but some of the later 240s were assembled late in their model years and may have gotten 3.1 in 90, but not likely. IF it has an 016 AMM, it ought to be LH2.4. I think some of the turbo LH2.4 AMMs are different though, I thought the NA ones sometimes had 015 circled below the id number sometimes. Then again, some have been able to run NA amms on LH2.4 turbo, so go figure.
 
one way to find out :).

i turbo'd my 2.4 without any modification to the fuel or ignition computers, and iwas able to run about 8psi without any problems

id think if you just slapped the turbo on there like i did, it would be fine to a certain point, then just MS it and be done

just my $0.02

ps, my car was a 1990 M47

-Brendan
 
My 1990 240 m47 has LH3.1. The serial number will tell you. If its got 88 in the number its lh2.4 and 82 its lh3.1. AMM looks different. Its not the hot wire type and is suppose to be more reliable along with a different TPS. Its a sensor not just a switch.
 
Thanks, guys- we are going to use the turbo ecu- we have automatics, so 2.4 is it.
Maybe MS later, when money catches up with ambition.
 
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