If you get the Full blown 70mm make sure you don't over tightened the clamp.

 

That was me

I haven't had time to take out the seals and weld it up.

Don't t-clamp aluminum!

 

I mean..... you'll strip your valve cover bolts if you tighten them too much but that doesn't mean your head is flawed.

^^How tight did you make it? I have T Clamps on mine and I know a bunch of people running the same setup with t clamps, just making sure I don't have anything to worry about.

 

the final torque numbers applied to the t-bolt when being used with the 70mm full blown should be done as you're performing a boost leak test. tighten it until it doesn't leak then leave it go.

I seen that video before though. It is a little disturbing. That has happened to more then one person, but as Blue91lx just said, anything can break if you over tighten it.

/

both Maperformance and Curt brown offer 70mm stock ported intake manifolds.

 

Remember this. The bigger the throttle body the lower the throttle response. Doesn't make sense I know but it's true.

I along with many many others have made damn crazy wicked power on 65mm. Intake mani porting is suggested but far from required. Cheap reliable power...

 

I know what you're saying. The hose blew off one time and so I clamped it a little tighter. Then I boost leaked the system and found a leak. Tightened it a little more, then this happened. It wasn't very tight. I used a 1/4" drive with a 10mm deep and was using very light pressure. Tightening the clamp on to snug and when it broke were the same pressures.

I think there were two problems.

1. I believe the adapter/reducer was causing a boost leak.
2. The OEM hose I bored out wasn't sufficiently smoothed to create a seal.

Since I modified the OEM hose and possibly over tightened the Tbolt, it is most likely my fault. I'm taking full resposibility. However, the crack started at the cast end seam.

I will be welding on +- 2" of 70mm aluminum tube with a lip on there soon. I probably won't be using a Tbolt on this part.

 

Nope, never have either.

Not sure where you heard that from. maybe just bad info.

Mil.spec only offers 65mm tb's for evo 8/9 & 64mm units for evo 6/7/10's.

Hope that clarifies things regarding Mil.spec tb's

fwiw, a larger tb should not be on your radar for someone with minimal mods imo.

now if your a track guy looking to pick up throttle response with minimal mods, then go for it

 

I tossed it out as an off the cuff comment and people started to run with it.

 

Any reason you want to upgrade the throttle body? If you are not looking to set a record I suggest to save the $$$ for something else. $300 is a good chunk of change that could go towards a set of tires, other maintenance, or even some track time.

 

The only reason I want a throttle body is because i have upgraded everything else (besides building my motor)... i do track my evo in the summer so a little more power / better throttle response is something that i would enjoy to have. I didnt want to spend big money (like the boomba TB) but it looks like the MILSPEC has good reviews and will do what i need it to. I just didnt know if there were ones to stay away from or not.. I had some people tell me it wont make a difference at all and others say it made a noticeable difference.

 

sounds like the main reason for that boost leak you had was because of using a stock coupler. those stock couplers suck after they have been ran for a long time, and even less reliable when someone tries to modify one by hand. Thanks for sharing your info , sucks you had to learn the hard way..

Anyone else have a better solution for coupler clamps besides t bolt? like a worm clamp that holds good boost and wont tear into the coupler when tightening it? Now im all paranoid about over tightening a t bolt

 

Advertised torque of a t-bolt clamp is typically about 70 in/lbs, or 8nm.

Tighten it just until it begins to bite into the rubber.

 

+1 fb 70mm here

 

I just ordered me the fb70mm rite now. Can't wait. I'm hoping to be able to hit high boost again.