and also do you bore out the intake manifold to match the jeep tb????

 

idk if this is true or not but i heard going past 55mm you start to loose performance.
[hr]

Having a throttle body too big can hurt overall performance, so unless you seriously changed the air flow characteristics inside your engine, I wouldn't use anything bigger than 55mm throttle body.
[/align][blockquote][align=center]CFM Flow Numbers:[/align][align=center]49mm TB flows 252 cfm
52mm TB flows 283 cfm
55mm TB flows 317 cfm
60mm TB flows 377 cfm[/align]At 8200 RPM a 122 cubic inch engine will need 290 cfm at 100% volumetric effiency, using the formula ((Max RPM/2)*Displacement)/1728. Rule of thumb is to go 10% over because a naturally aspirated engine can go above 100% volumetric efficiency because of cam overlap, header design, etc. Go above that and you kill low end because of reduced velocity, go below that you starve the engine for air at top end. 110% is volumetric efficiency is 319 cfm."
Based on this, 55 mm does seem to be the option for naturally aspirated (non-turbo) engines.
__________________________________________________ _____________
Similarly, going beyond 55mm is likely to have a negative effect on performance. (bottom end torque will be less, slowing ETs.)[/blockquote]

 

^^^^This is true. If you havent ported your intake or dont have a good amount of mods then anything bigger than 55mm will make you lose power. And to answer your question winplet, no you dont have to bore or port your intake manifold, but it is reccomended if you decide to go with the Jeep TB because of how big it is.

 

oko still have a problem with the iac motor being in the wrong spot and hitting the intake also the vacum vent that is on the stock tb is not on the jeep tb,i would think to drill and put a port for that vacum line?am i right help please

 

any help on this issue please