LTG Swap (Page 1/2)
RandomTask MAY 29, 08:58 PM
Hello,

I plan on doing an LTG swap into my '88 Formula over the next couple of months. I have a fairly good understanding of everything required other than the transmission. I want to use the 6 speed F40 however from what I've researched, it appears the LTG uses a "High Feature" bolt pattern. Are there different bolt patterns from different F40 transmissions? (As in, do I need the F40 from a Saab vs one from a G6?) Thanks,
Dennis LaGrua MAY 30, 11:10 AM
Forum member Roger Thelin makes many of the parts needed to do the Ecotec swap but only for certain model years and certain transmission choices. On your planned swap I would just try to use the transmission that came with that engine . Also bear in mind that the LTG engine is of a direct injection type that may present challenges in powertrain control management.

------------------
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"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
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Daryl M MAY 30, 11:46 AM

quote
Originally posted by RandomTask:

Hello,

I plan on doing an LTG swap into my '88 Formula over the next couple of months. I have a fairly good understanding of everything required other than the transmission. I want to use the 6 speed F40 however from what I've researched, it appears the LTG uses a "High Feature" bolt pattern. Are there different bolt patterns from different F40 transmissions? (As in, do I need the F40 from a Saab vs one from a G6?) Thanks,



Why do you believe that the LTG has the High Feature bolt pattern? It is my understanding that only the High Feature engines use that bolt pattern.
RandomTask MAY 30, 09:16 PM

quote
Originally posted by Dennis LaGrua:

Forum member Roger Thelin makes many of the parts needed to do the Ecotec swap but only for certain model years and certain transmission choices. On your planned swap I would just try to use the transmission that came with that engine . Also bear in mind that the LTG engine is of a direct injection type that may present challenges in powertrain control management.




I wasn't aware of any FWD MT platforms that this engine came in. I could be wrong though. Are they that similar to the previous 2.2 ecotec/ And using the GM ECU kit for the engine.


quote
Originally posted by Daryl M:


Why do you believe that the LTG has the High Feature bolt pattern? It is my understanding that only the High Feature engines use that bolt pattern.


I started searching. Complete face palm. I was originally contemplating an LFX swap, hence getting confused about the bolt pattern.
msweldon MAY 30, 09:50 PM
From my research on mating up transmissions to the high feature v6's, the F40 came in 3 bellhousing configurations, 60degV6, Ecotec, and High Feature V6.


The LTG did come in the Buick Regal 2.0T and was mated to an F40 with the ecotec pattern... hit up ebay for Buick F40 transmissions to get a good look at the ecotech bolt pattern..

I had an LY1 ecotech F23 that I tried mating up to a high feature v6... the alignment pins work but the rest is way off....waaay off....
msweldon MAY 30, 09:58 PM
From my research on mating up transmissions to the high feature v6's, the F40 came in 3 bellhousing configurations, 60degV6, Ecotec, and High Feature V6.


The LTG did come in the Buick Regal 2.0T and was mated to an F40 with the ecotec pattern... hit up ebay for Buick F40 transmissions to get a good look at the ecotech bolt pattern..

I had an LY1 ecotech F23 that I tried mating up to a high feature v6... the alignment pins work but the rest is way off....waaay off....
fieroguru MAY 31, 12:09 AM

quote
Originally posted by msweldon:
the F40 came in 3 bellhousing configurations, 60degV6, Ecotec, and High Feature V6.



The F40 came in at least 1 other bellhousing (possibly more): Opel Turbo Diesel. The starter for that one is over the differential:


There is also at least 2 different bolt boss patterns on the differential, so transmission mounts are not universal. The bracket in the picture fits the G6 version, but not the other one. The Regal is like the one in the picture and doesn't match the G6 version.


The front side of the transmission is equally different between the G6 and other F40s. The 4 large bolt bosses commonly used for F40 transmission mounts with the G6 version don't exist on the Regal and other versions. This is the non-G6 version:


There is also at least 2 different shifter mounting bolt patterns (3 Bolt G6, 2-bolt Regal, some other models mix and match...)


Lastly there is at least 2 different clutch line connection types G6 version is different than the Regal version. The G6 one comes out of the bellhousing horizontal, the Regal and some other exit the bellhousing vertical.

ennored MAY 31, 09:40 PM
LTG and all Gen II Ecotec (Gen II as we call them inside GM), the ones with the exhaust and intake flipped from the earlier Ecotecs, have a unique bell housing pattern. Chevy performance sells/sold a manual and auto trans setup for it, as well as a FWD F40.
Black88GT JUN 03, 12:23 PM
Any concerns about overheating? These motors are known to run hot. I am very interested in an LTG swap too because it's a great motor, very tunable, and most importantly - LIGHT, but the heat issue gives me a bit of pause. I have this motor in my Cadillac and it's smooth as silk (2017 CTS). BNR tuned with some minor additional mods will yield 300 hp easy, and it will do it hundreds of pounds lighter than a 3800 SC.

As others have mentioned, they do mate the LTG with a FWD 6 speed in the Buick Regal. Also, GM makes a standalone harness but I'm not sure if it only works with the performance LTG motor they sell (waaaay too much money IMO).

Keep us updated!
RandomTask JUN 04, 03:06 PM

quote
Originally posted by Black88GT:

Any concerns about overheating? These motors are known to run hot. I am very interested in an LTG swap too because it's a great motor, very tunable, and most importantly - LIGHT, but the heat issue gives me a bit of pause. I have this motor in my Cadillac and it's smooth as silk (2017 CTS). BNR tuned with some minor additional mods will yield 300 hp easy, and it will do it hundreds of pounds lighter than a 3800 SC.

As others have mentioned, they do mate the LTG with a FWD 6 speed in the Buick Regal. Also, GM makes a standalone harness but I'm not sure if it only works with the performance LTG motor they sell (waaaay too much money IMO).

Keep us updated!



My goal now is to source a wrecked 2012/13 Regal GS as a donor car. Right now there's one in NM on copart but I'm not excited about shipping it across country.

I'm not worried about the heat aspect; I can always do cooling upgrades. Also, car will be more of a road toy than anything so doubt it will be taxed all that hard.