[GUIDE] F35 to F23 (with LSD) Transmission Swap
- Thread starter OptimizePrime
- Start date
BSinvestments
Active Member
It’s all about the spacing, you have to measure the spacing of the TOB and the clutch fingers. There’s instructions videos by zzp
Ross
Goblin Guru
Here is a pic of the spacer plate, with the flywheel sitting in the center.
ah.b.normal
Goblin Guru
This is my full report for 2023, RE: Transmission stuff. If you're not interested in starter plates and such pass over all of this post.
In my Junk yard trips(as I was searching for parts I needed like maybe a Fiero shifter? I was surveying for those "starter plates", as the plates are no longer available new.
I generally only found them on F35 applications, ALL F35 units I found had that plate.(to be scientific, I found roughly 12 units in Montana, Idaho, Utah, AZ and TX.) I found 2 similar looking plates on Automatics?? Weird! Those may have been a different thickness but I did not measure any of them.
I saw ~5X as many F23(much more common trans) and only one had that plate; it was an F23 behind a different Saturn motor, pre 2005(same bellhousing pattern). I found an F35 in a larger Saturn sedan!?(LSD? unknown, IIRC, bolted to an N/A EcoTec motor.) Many F23's in Ion models. I surveyed Cobalt, HHR, G5, G6, Ion and most Saturns. Also Saab 95(?)Equinox and Saturn Vue. I also searched many 2000-2004 Saturn, Cavalier/Sunbird(Fire?) EcoTec motors started in these models some date after 2000. Except the one above, I only recall seeing F23 behind Ecotec motors.
I did not survey any Sky/Solstice as none were found and use a very different RWD trans.
I know the Eco Tec was used in the Malibu models as well, but have never seen a Malibu with a manual trans.
I have seen one G6 with an F40 in El Paso(summer '23, Boy was I surprised!). I have seen one Regal with an F40(Spring '23) 2) F40's in SAAB's; oddly all found in Springfield, MO. I was not surveying for the Starter Plate then, so unknown IF the F40 used it. I didn't even look at their motors! Probably turbo? I should have bought those Missouri F40's as the junk yards wanted $110. each. Salvage man said he KNEW they only fit those cars and nobody was searching for them!?? Live and learn! IF the guy at the junkyard is selling cheap because "nobody is calling him for that part", buy, pack the stuff up and leave quietly.
I did not see any Opel, Vauxhall or Alfa Romeo.
@Rauq I dont think there was a plate when I fittet the F23 to the LSJ, but maybe that was the reason that the oil cooler did not fit without taking some material off the gearbox housing.
Scott #321
Well-Known Member
When I installed the f23 on a LNF I used the spacer plate with F35 TOB and it has worked fine.
Rauq
Goblin Guru
I wasn't able to get ahold of them in Sept/Oct 2021. Justin Reed said his TeamGREEN insert was entirely unimpressive as well. I ended up putting an OBX LSD in it which was $400 then. I don't see that LSD for sale anymore on eBay (where I got mine), but I did find this: https://www.ebay.com/itm/185573317225. I recall having read somewhere that MHP and MFactory are just rebrands of OBX. There were known issues with OBX including sub-spec spring washers and helical gears installed backwards. I fixed both at the same time with a hardware kit from this guy. Might be worth reaching out to see if they've heard whether MHP/MFactory LSDs are functionally the same as OBX, in which case his hardware kits would probably work just the same.
I would think your other options include other F23 LSD inserts like this one on eBay: https://www.ebay.com/itm/265334017602. I wouldn't think too much of them being central European, as the F23 was a way more popular trans in various European GM platforms.
I would think your other options include other F23 LSD inserts like this one on eBay: https://www.ebay.com/itm/265334017602. I wouldn't think too much of them being central European, as the F23 was a way more popular trans in various European GM platforms.
Markm
Well-Known Member
All good info, Thanks. I saw the one from Serbia and I’m kinda skeptical about going that route. I was leaning towards the insert since our car probably won’t see very little if any track time. I haven’t seen a torsion type LSD since the gen4 Camaro back years ago. I did find this one on eBay https://www.ebay.com/itm/265761241675?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=5QiFtIN8THG&sssrc=4429486&ssuid=kpA7R5PmSEG&var=&widget_ver=artemis&media=COPY
Do I see that correct that all this LSD inserts do is to create pressure on the face of the gears, which leads to friction and stops the free spin?
Markm
Well-Known Member
pretty much that’s how it works
Ross
Goblin Guru
The Quaife differential is a Torsion Gleasman type LSD, mechanically transferring torque to the wheel with traction.
This is what is used in the Cobalts with the G85 chevy equipment code, but can be added to a open diff transaxle.
It makes a big difference for controlling the rear of the goblin.
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Rauq
Goblin Guru
In theory... this feedback is what swayed me against it.
Don't quite get it, what that has to do with a LSD.
Rauq
Goblin Guru
Was supposed to link here? No idea how it got there...
dfkitcar.com
Justin Reed Racing DF Goblin
I've been bad about not updating the info on my build along the way, but that's gonna stop now. My most recent rebuild this year involved basically rebuilding the entire car minus the front suspension. That means a new engine, transmission teardown inspection, wilwood pedal box, surge tank fuel...
Do you happen to have a link to those videos? I keep seeing people say that I might not need the plate at all. Haven't really found much info on it anywhere but here.
BSinvestments
Active Member
Here you go
newbtrying
Active Member
I posted earlier about my LSD installation process... well, more than a year later and my engine is finally rebuilt (extremely delayed due to part availability and my unnecessary upgrades.) Anyway, I have some very dumb questions that I would like any of you to spell out really simply for me to understand please.
I have my original LSJ flywheel/clutch installed on my rebuilt motor (I plan on upgrading these next winter or so) but the F23 has the matching slave cylinder and throughout bearing (new on trans) here are my questions:
1) Do I have to replace this with the LSJ slave cylinder/clutch pipe? I do not have these anymore.
2) If I can keep the new slave cylinder and clutch pipe, which I *think* I can, how do I get the hydraulic clutch elbow (circled in pic) mated to the clutch pipe? what parts, specifically?
3) Am I correct in thinking that I do not need the master clutch line (line attached to hydraulic clutch elbow in pic)?
I have my original LSJ flywheel/clutch installed on my rebuilt motor (I plan on upgrading these next winter or so) but the F23 has the matching slave cylinder and throughout bearing (new on trans) here are my questions:
1) Do I have to replace this with the LSJ slave cylinder/clutch pipe? I do not have these anymore.
2) If I can keep the new slave cylinder and clutch pipe, which I *think* I can, how do I get the hydraulic clutch elbow (circled in pic) mated to the clutch pipe? what parts, specifically?
3) Am I correct in thinking that I do not need the master clutch line (line attached to hydraulic clutch elbow in pic)?
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