car wont gain go over 33-3500 rpms or less

[Nitrous4ME]

i have a 97 rs 3,8 auto...i jsut put in a new trans ...but the car now wont go over 2500 rpms sometimes, and others times it wont go over 3200 it strains as it raises in rpms also it seems like it wont shift into second even though if i put the car in sgs it moves im thinking its an engine problem and the car isnt getting enough rpm to shift...what would cause this seems to run perfect at idle maybe a small miss but nothing bad and its not throwing a code...is this a clogged cat...car has 180k on it and what looks like a stock cat...doesnt seem like a fuel issue car has a 225 in it and ran fine with it before....any help would be appreciated....thanks

[Bonemaro]

Re: car wont gain go over 33-3500 rpms or less

This is what my car did when the cat was clogged.

Can you tell if the converted is getting unusually hot?

[Nitrous4ME]

Re: car wont gain go over 33-3500 rpms or less

the cat and ant the y pipe are hotter than the cat back so im guessin thats the problem there and the shifting thing is because of the vehicle speed sensor not regestering so i gotta swap them out..this has been my worst trans swap ever and it on the dd lol