throttle body size

wlink1

Banned
Apr 12, 2007
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Winston Salem
What would you recommend on TB size 70mm 0r 75mm? I have or will have on the car when I install the TB. Headers, O/r H pipe, 40 seris flows, Explorer intake, CAI, underdrive pullies and soon will have (75mm MAF w/24 or 30lb injectors, Tweecer) hopefully by end of month on these 3 items. Also what size is the blueovalindustires TD adapter?
 
If you are dead set on getting an aftermarket throttlebody, I'd do like Chris recommended and match the size of your intake opening.

If it were me, I'd see about putting the cash elsewhere on your turbo build, the stock throttle body will flow more than enough for what you've got at the moment and may actually give you some problems idling without being able to tune it.

Looking forward to hearing more about your turbo build!

Wes
 
I believe the GT40 is a 70mm opening...

And they are right, 70mm is more than enough...it flows much more cfm than your engine can possibly breathe in...

Your front opening maybe 70mm, but a couple inches in, it will neck down to the 65mm range...

A Systemax has a 75mm opening at the front but necks down a couple inches in to around 65mm...so what good does the 75mm opening do?:D
 
A Systemax has a 75mm opening at the front but necks down a couple inches in to around 65mm...so what good does the 75mm opening do?:D

this is like preaching to the choir; i'm sure you know this as well as me.

smoother walls makes for fewer air flow disruptions. putting a 65 mm throttle body on an intake that has a 75 mm opening just doesn't make sense, even if the intake tapers down to 65 mm inside. the taper is designed into it to increase the velocity of the air as it flows through the intake towards the valves.
 
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ended up costing me $180 to have it 2 day air but still cheaper than just buying the throttle body but I needed it here by Friday as my brother an I are installing my intake Friday so I will let you know How it works out. Hoping to get it to the track just to see what it does in the 1/8th on Friday as well. If I can get the freakin drivers side VC to seal
 
this is like preaching to the choir; i'm sure you know this as well as me.

smoother walls makes for fewer air flow disruptions. putting a 65 mm throttle body on an intake that has a 75 mm opening just doesn't make sense, even if the intake tapers down to 65 mm inside. the taper is designed into it to increase the velocity of the air as it flows through the intake towards the valves.

Right, you were preaching to the choir:nice:

I see so often that people say a 75mm TB is what you need to FLOW and get power, but that is not the case. That is the point I was trying to make. That a 65mm will flow plenty, whether it is matched up...well that is something else to discuss...
 
Got my explorer intake, trick flow spacer and bbk 75mm installed and it feels like I am driving a new car. Next on the list 24 or 30lb injectors and tweecer. Hopefully by the end of August. Thanks for all the onfo.
 
I doubt you will want either of those injectors.

If you are indeed going with a turbo setup, you're going to want 42lb +

With your current setup, there is no point upgrading the injectors. 24 or 30lb will be too small for a turbo setup, and too big for your current setup.
 
installing a bigger tb than stock without aftermarket heads and just bolt ons is gonna make you lose power and torque....wait till you put better flowing heads.....i found out the hard way....i put on a 70mm tb after i put on my edel performer mani and right off the bat noticed a lose of torque.....just wait
 
Got my explorer intake, trick flow spacer and bbk 75mm installed and it feels like I am driving a new car. Next on the list 24 or 30lb injectors and tweecer. Hopefully by the end of August. Thanks for all the onfo.

Be sure your opening on the intake is opened up to 75mm. I haven't seen a loss of power yet in working with a car with "too big" of a properly matched throttlebody/CAI setup - just a touchy throttle.

I've got it on my todo list to dyno a car with a few different throttlebodies (stock, 70, 75) and measure datalog airflow at the MAF to see the gain (if any).

Wes