I have a 99 4.6. I have a bbk CAI and BBK LTH's. Can anybody tell me what would be the best size TB. 70 or 75mm. Will an intake plenum make a difference for what they cost? Who makes the best TB and plenum?Would I need to go to a bigger sensor that's on the CAI? Thanks

 

They are a decent mod for the money. 75mm is fine they are the same price so Id go with the 75..rpmoutlet has some nice packages real cheep

 

i would do a 75mm. you wont be able to tell the difference but if you do more upgrades 75mm will be better. no there will be no difference between any of them, or if there is not big enough for you to notice. no bigger sensor needed, i think the stock go up to 90mm? im sure someone will correct me if im wrong. i would check late model restoration, because in my last mm&ff there was a performance products one for 200 for the combo... what a good deal!!! i ordered that one

 

the late model restoration, do you have a specific web site or magizine?

 

I also ordered the Professional Products combo... HOPEFULLY I will be installing it today (its like 20 degrees out )
I believe 03oxfordgt is right, the stock sensor is up to 90mm. I got mine for $240 shipped. Check out ebay thats where I bought mine!

 

The stock plenum is the weak link. [/align][/align]The OEM 65 mm TB and plenum flow 460 cfm at 2 inHg. The OEM TB and any after market plenum will flow 520+ (550+ with an Accufab plenum) at the same differential.[/align][/align]OTH, the OEM plenum with a 75 mm Accufab TB can only flow 490 cfm (also at 2 inHg).[/align][/align]I.e. do the plenum first...[/align][/align](here's Accufab's flow data, about 1/2 way down the page)[/align]

 

I have the performance products TB,Plenum on my car,i like it alot.seems to do well.