Hey there guys!
I needed a bit of help with an engine swap i'm currently doing. The motor is the h22 red top from the SH and the transmission is the m2u4. Now seeing as this swap is going into a civic and I was told the transmission wouldnt be possible to hookup due to the ATTS module (something about the intermediate shaft going into the module then the block). Anyhow, When i found out it wasnt compatible I bought an m2a4 for the motor but my mechanic insists on not scrapping the the m2u4 saying it has better gearing and FD and says he'll swap the gears from the m2u4 housing into the m2a4.

I just wanted to double check with you guys and find out if that was even possible? I've already wasted time because when I was buying the engine and called this mechanic he gave me the go ahead to get it despite me telling him a dozen times about the ATTS and its incompatibility he kept reiterating we would be able to work around it fine. Later he said the ATTS was crap and were better off going for the m2a4 and swapping out the gears.

has this been done before ? possible?

thanks!

 

the m2a4 is a non lsd box you would be better with a m2b4 or a u2q7 if you can get hold of either of those lsd equipped box.
Can you not remove the atts from the engine and keep the box if you keep the atts you need to run the prelude management with a piggyback to keep it working.
I know over here in the US you seem to have a downer on the ATTS but its a great system when its working right.

 

yeah the transmissions you mentioned are ridiculously hard to find here (asia)..I'm getting an LSD installed in that gearbox instead though. Came across a T2W4 which apparently is one of the best H22 LSD transmissions according to what i've read but the seller is demanding $750 dollars for it :/

initially my mechanic said he'd be running the gearbox without the ATTS.. then he said something i dont really get as i'm a bit of a newbie to this but something about having to find the right combination of axels and that the intermediate shaft goes into the module and then into the block. So he had me get the m2a4 to transfer the gears into its housing. i'm just thinking now whether that would even work. Also wont the p5p throw a code when its unable to find the atts? its obd2 so i'm guessing i wont be able to disable the CEL either? :/

the ratios for the 2 boxes are below.. is this even worth it , the diff doesnt seem much ..

---------------
M2A4 : 3.307 - 1.950 - 1.360 - 1.034 - 0.787 - 3.000 - 4.266
M2U4 : 3.285 - 1.956 - 1.344 - 1.034 - 0.812 - 3.000 - 4.266

 

Have fun trying to bolt up a different trans to the SH block... won't happen without a custom fabbed adapter. Do a search on here for the m2u4 trans and you'll see what you're up against. If you want to keep it simple, just use the SH trans mated to the ATTS unit. Without the ATTS control unit, it will just run like an open diff. It's extra weight and you can't run an LSD, but it will get you going if time and/or cost is an issue.