Originally Posted by 03 tls nc

The J35A3 is the way to go, forged crank, same heads, runners, injectors and IM as the J32A2 they even use the same reinforced block. The oil pressure spring and valve is different but can be changed with new Honda parts for less than $10. The cams and springs are different but if not changing the compression ratio probably not worth changing. The J35A3 has 10:1 compression where the J32A2 has 10.5:1 due to raised pistons in the J32A2, Milling the J35A3 head .020" will raise the compression to 10.5:1 and cost less than $100 at the machine shop. The 35 really likes the light weight crank pulley since it has a longer stroke and heavier rotating assembly. The TLs harness is a direct fit with no modifications, they both use the flapper in the IM and don't believe the hype if you are NA keep the flapper hooked up. Just because it always comes up the J32A2 uses a 1mm larger intake valve but they both use the same valve seat so it becomes a disadvantage due to shrouding its a moot point.

As far as the auto trans it can be re-built to hold the power of a 3.5 with no problem. Use the full Tran-Lab shift kit (use the race/towing specs), Raybestos GPX clutches, Level 10 TC and TCC valve. Use only Honda fluid and change 3qts at least every 3rd oil change, sooner if more power or driving hard. The biggest key to keeping it from killing its self it to adjust the A-B solenoids, you will need the tool from Sonnex its about $25 and is a must. You can take an older stock trans and extend its life by keeping the fluid changed and the A-B solenoids tuned correctly.