Does anyone have any performance gain numbers on a tb bored by ARD to 58mm? Or is the one done by AFX at 55mm better? Is the extra $40 worth the extra 3mm?
Thanks!

where do you get the ard one from?

ARD
www.advancedracingdynamics.com

or you can have www.ConceptIllusions.com Bore it out, let them know Walker sent you.. not sure what price its going for right now, you'd have to ask Shawn.

AFX tested the 55mm as the best size for NA. 58mm on a stock TB is EXTREMELY thin. Seems like one good bump and your TB neck would snap off.

If you're turbo get a 60mm Modern Performance TB, if not stick with the 55mm.


And the reason is if you run anything higher than 55mm your air velocity drops. You get more air in, but it's running at a lower speed. So you'll get more torque off the line, but you'll actually lose horse power. Stick with the 55mm...I'd sell you mine but someone just bought it.

aaron so a ported and polished intake manifold wouldnt be benificial with a ported t/b .. to much velocity loss?

Originally posted by oRACLe063
aaron so a ported and polished intake manifold wouldnt be benificial with a ported t/b .. to much velocity loss?

Well I'm no engineer so I'm basically repeating the same shit I've read on this board a kabillion times. There are certain mods that are beneficial and ones that are not. If you are running a stock head with stock intake and exhaust then porting and polishing your intake manifold wont do much of shit. But if you have a good exhaust system and some bitchin cams with a nice CAI then yes, a P&P intake mani will do you some good.


So if you have the supporting mods to utilize a 60mm tb then more power to you, but if you are running basic bolt ons then a 55mm one will be the best for you.

when the manifold goes in im going to have the following

cold-air
ported t/b
ported manifold and runners
pacesetter headers
erts high flow cat
and my cat back

thats the whole shibang

55mm is the perfect size for NA applications. Anything larger and I believe you lose topend power. If you plan on boost then go larger. I recommend the 60mm Modern Performance version.

Originally posted by WDs RS-T
or you can have www.ConceptIllusions.com Bore it out, let them know Walker sent you.. not sure what price its going for right now, you'd have to ask Shawn.

Do they actually bore it out, or do they just cut out the hump?

They actually bore it out. If you have some time on your hands, you could even port it out yourself. Aluminum is pretty soft so it take too much work, just make sure you use a micrometer to keep it even all the way around.