Lets talk about Bigger Throttle Bodies

[superskaterxes]

so im slowly putting all of the pieces together to make the most EFFICIENT power i can out of my setup. Being that Scotts IM is the next and pretty much last part i need to complete my setup i figured why not upgrade the TB at the same time.

its been said that a 60mm (stock size) can take you north of 600-800whp. Im not sure how (or why) people would use a 2" (usable area) TB to achieve that but its only good for about 525CFM when tested at NA levels (aka no boost). hopefully @06Speed6 can chime in here.

now with a turbo you can always PUSH through restrictions to gain more power but you will have diminishing returns and are just hurting the VE of your engine/setup. Regardless of the numbers the stock TB wont continue to make efficient WHP above 450-500.


so the thing about TB's is that the way the TPS and ECU correlate is VERY finicky and you must match the voltage ranges perfectly or else you will throw codes and the ECU freaks out.

this is what our stock (MS6, havent verified for the 3) voltage correlation looks like:













its basically an inverse relationship between TPS1 and TPS2 from 0.5 to 4.5V. This is done as sort of a "check" with one another to make sure the throttle plate is at the correct angle and everytime you key on the TB goes through a startup check to ensure this.

now theres 6 wires on our TB, 2 for the motor itself, 1 for TPS1 and TPS2, 5v reference, and ground as u can see here.














now AFAIK @Erich is running the dodge hemi TB which is nearly identical to ours in voltage correlation and wiring configuration but uses a different bolt pattern and connector. its 80mm which is just shy of 3" worth of usable area. some tests that i have read online said this is good for 900-1100CFM worth of air on NA applications (aka even before boost is applied).

here is what i dug up about the 2005+ hemi 5.7L TB.

5.7L 6.1L 6.4L Hemi V8 Throttle Bodies - The Fastman

Dodge Part #53032801AC, currently about ~$130 brand new


















it looks like the dodge TB goes from 0.3 to 4.7v which is still ok because our ECU's codes only get thrown below 0.2v and above 4.85/4.9v depending on which TPS it is.


now the shitty part is i have not been able to locate a pigtail/harness for this TB ANYWHERE. i have searched high and low and other then cutting one off at a junk yard we're SOL as far as getting this to be a clean install. the VW MK4 VR6 uses an almost identical connector stock except you just need to shave one little part off or something. they have apparently been using these TB's for years for their BT cars.




does anyone else have anything to add to this? @SPEED6 KILLAH? research you have done? for all you experts asking why we just cant use the v6/CX-9 TB is because their voltage correlation is completely different as seen below. AFAIK @kmac is running this TB but he had to hack the shit out of the TPS sensors to get it to work and said it wasent worth it.

[mrmonk7663]

Good research. This effectively kills the cx9 72mm option. The hemi option is still in play, but at almost 3" it is somewhat "large" for mild turbos it would seem, bnr, 2871, etc. Surely there has to be other TBs in a 70mm range that could work.

[SilverDemon]

*sniff.....sniff*

Hmmmm I smell some custom work that needs to be started.....

[MS3-a(sore)ASS-rex]

So many fucking numbers!

[TiGraySpeed6]

subscribes
tries to look intelligent
fails, but wants to read along anyway....

[rfinkle2]

@kmac is successfully running a bigger throttle body as well.

[Don06speed6]

In for the epicness to follow.

[InFeXIoN]

Originally Posted by rfinkle2 @kmac is successfully running a bigger throttle body as well.

But as stated not worth the headaches to get it to work. =(

Sent from my Galaxy Nexus using Tapatalk 2

[Liquid3Speed]

As for the pig tail, why not just go to a chrysler dealer and buy the connector body, seals, and terminals, then make the "pigtail"? It would only take 10 minutes to make.

[SPEED6 KILLAH]

I have been do some research come across a honda civic si TB that skunk2 make 72mm that should bolt on and work. Now the connector sytle that on the skunk2 mazda use to used on there 03 to 05 mazda 6 2.3 before swtiching over to a new style connector. If we can contact skunk2 to make it so that all we do just swap the TP module on the TB over to theirs..

http://cms.skunk2.com/id/480/Drive-B...Throttle-Body/







I also have tooking a part DISI TB to see how it looks inside here are some picture..






TP module so the two bottom pin are for the motor and the middle hole is to apply support from a center pin on the throttle body and the top read the tp position


TP adjust screw reference


reference screw for self check when trun on and off the car and of always go through a self check.. That is the loud clicking noise when the car off for about a couple sec and key on and engine off..

Now on this gear it has magnets that the TP module picks up

[jack_hammer]

Potentially dumb question: why not just use a ported tb? Not a big enough difference?

Sent from my LG-MS690 using Tapatalk 2

[doubleflusher]

Originally Posted by broncojd78 Potentially dumb question: why not just use a ported tb? Not a big enough difference? Sent from my LG-MS690 using Tapatalk 2

I have a Grimmspeed ported TB and it's only a minor enlargement.

Like the jump from Asian to white man's penis.

What we really want is a black man's penis sized TB.



I'm just trying to put this in a context that most members will understand.

[Lex]

Originally Posted by doubleflusher I have a Grimmspeed ported TB and it's only a minor enlargement. Like the jump from Asian to white man's penis. What we really want is a black man's penis sized TB. I'm just trying to put this in a context that most members will understand.

Were they unable to port it further? I assume the remachined the throttle plate?

Another thing to consider. If the ECU uses the throttle position to determine tip-in enrichments and idle which it does at least to some extent, changing the size dramatically will affect driveability and you may see the car behaving more abruptly during transitions. I would get in touch with COBB and ask about tip in enrichment tables as these will come into play here.

[SilverDemon]

Here is a question for everyone (I am probably off on this, but hear me out)

What is the largest size outlet on the compressor side of everyone's turbo?

What is the largest size I/C piping that most people are running?

Am I wrong in thinking that if I increase the size of the TB, that it will not make much of a difference, since the maximum amount of air can only pass through the smallest point of the intake system?

I really do not have much in the way of experience in exactly how this will pan out, since most people are running a turbo that has, lets say a 2.5" outlet, along with 2.5" I/C piping.

Something to think about before we jump into the bigger is always better idea.

[doubleflusher]

Yes.

They also replaced the bolts that hold the plate to the shaft. They have smaller heads.

People can replace the bolts on their own, as it's a fairly simple procedure.

[superskaterxes]

Originally Posted by Liquid3Speed As for the pig tail, why not just go to a chrysler dealer and buy the connector body, seals, and terminals, then make the "pigtail"? It would only take 10 minutes to make.

you have part numbers? ive never heard of doing this....................

[bcmurphy87]

Originally Posted by SilverDemon Here is a question for everyone (I am probably off on this, but hear me out) What is the largest size outlet on the compressor side of everyone's turbo? What is the largest size I/C piping that most people are running? Am I wrong in thinking that if I increase the size of the TB, that it will not make much of a difference, since the maximum amount of air can only pass through the smallest point of the intake system? I really do not have much in the way of experience in exactly how this will pan out, since most people are running a turbo that has, lets say a 2.5" outlet, along with 2.5" I/C piping. Something to think about before we jump into the bigger is always better idea.

So after readin this i came to the conclusion that the hemi should be more than enough for us? Im not the most critical thinker here, but i know i love POWA.

[superskaterxes]

Originally Posted by SilverDemon Here is a question for everyone (I am probably off on this, but hear me out) What is the largest size outlet on the compressor side of everyone's turbo? What is the largest size I/C piping that most people are running? Am I wrong in thinking that if I increase the size of the TB, that it will not make much of a difference, since the maximum amount of air can only pass through the smallest point of the intake system? I really do not have much in the way of experience in exactly how this will pan out, since most people are running a turbo that has, lets say a 2.5" outlet, along with 2.5" I/C piping. Something to think about before we jump into the bigger is always better idea.

AFAIK the turbo outlet is negligent cause its part of the "source". obvi garrett isent going to design a turbo outlet that is too small for the wheel inside.

here's what their turbo tech says about IC piping

Charge Tubing The duct diameter should be sized with the capability to flow approximately 200 - 300 ft/sec. Selecting a flow diameter less than the calculated value results in the flow pressure dropping due to the restricted flow area. If the diameter is instead increased above the calculated value, the cooling flow expands to fill the larger diameter, which slows the transient response. For bends in the tubing, a good design standard is to size the bend radius such that it is 1.5 times greater than the tubing diameter. The flow area must be free of restrictive elements such as sharp transitions in size or configuration. For our example: Tubing Diameter: velocity of 200 - 300 ft/sec is desirable. Too small a diameter will increase pressure drop, too large can slow transient response. Velocity (ft/min) = Volumetric Flow rate (CFM) / Area (ft2)

for my estimated 915CFM im going to need 3-3.25" IC piping to stay in that 200-300FPS range. now my coldside is 3" and ive always heard you do a larger cold side then hot but im not sure why lol (wasent the reason behind me doing it).

i found this fancy chart online that references CFM to air speed. apparently after 0.4 Mach air becomes turbulent so you want to avoid that. it looks like 2.5" piping can still support 900 CFM but of course its at the top of the range for smooth flow.

2" piping 1.57 x 2 = 3.14 sq in 300 cfm = 156 mph = 0.20 mach 400 cfm = 208 mph = 0.27 mach 500 cfm = 261 mph = 0.34 mach 585 cfm max = 304 mph = 0.40 mach 2.25" piping 3.9740625 sq in = 1.98703125 x 2 300 cfm = 123 mph = 0.16 mach 400 cfm = 164 mph = 0.21 mach 500 cfm = 205 mph = 0.26 mach 600 cfm = 247 mph = 0.32 mach 700 cfm = 288 mph = 0.37 mach 740 cfm max = 304 mph = 0.40 mach 2.5" piping 4.90625 sq in = 2.453125 x 2 300 cfm = 100 mph = 0.13 mach 400 cfm = 133 mph = 0.17 mach 500 cfm = 166 mph = 0.21 mach 600 cfm = 200 mph = 0.26 mach 700 cfm = 233 mph = 0.30 mach 800 cfm = 266 mph = 0.34 mach 900 cfm = 300 mph = 0.39 mach 913 cfm max = 304 mph = 0.40 mach 2.75" piping 5.9365625 sq in = 2.96828125 x 2 300 cfm = 82 mph = 0.10 mach 400 cfm = 110 mph = 0.14 mach 500 cfm = 137 mph = 0.17 mach 600 cfm = 165 mph = 0.21 mach 700 cfm = 192 mph = 0.25 mach 800 cfm = 220 mph = 0.28 mach 900 cfm = 248 mph = 0.32 mach 1000 cfm = 275 mph = 0.36 mach 1100 cfm max = 303 mph = 0.40 mach 3.0" piping 7.065 sq in = 3.5325 x 2 300 cfm = 69 mph = 0.09 mach 400 cfm = 92 mph = 0.12 mach 500 cfm = 115 mph = 0.15 mach 600 cfm = 138 mph = 0.18 mach 700 cfm = 162 mph = 0.21 mach 800 cfm = 185 mph = 0.24 mach 900 cfm = 208 mph = 0.27 mach 1000 cfm = 231 mph = 0.30 mach 1100 cfm = 254 cfm = 0.33 mach 1200 cfm = 277 mph = 0.36 mach 1300 cfm max= 301 mph = 0.39 mach

and if the stock TB can only support 525CFM then it will always become a restriction past that even if more boost is added. just doesent make sense to put a restriction anywhere in the system if u can help it.


P.S. lex brings up a good point about the tip-in tables. We should def check with @Cobb Tuning and @David@COBB about this =D

[bcmurphy87]

Originally Posted by superskaterxes you have part numbers? ive never heard of doing this....................

We have an AWFUL lot of chevys in the local yards around here and the pull-a-parts. Good chance i could score a few. Perks of living in the dirty south where rednecks and gansta ride chevys.

No clue what i need to get though what year make and models work for this?

[Boosted Beluga]

Sliverdemon has a point.

[bcmurphy87]

My cold side is now almost complete 3.5 for the blow thru and i will be adding the 3in section for the 5th port so it seems it should already out flow the stock TB correct?

[superskaterxes]

Originally Posted by bcmurphy87 We have an AWFUL lot of chevys in the local yards around here and the pull-a-parts. Good chance i could score a few. Perks of living in the dirty south where rednecks and gansta ride chevys. No clue what i need to get though what year make and models work for this?

AFAIK its any dodge 5.7/6.1L hemi from 2005+, so like durango/charger/ram/dakota

[djuosnteisn]

Originally Posted by SilverDemon Here is a question for everyone (I am probably off on this, but hear me out) What is the largest size outlet on the compressor side of everyone's turbo? What is the largest size I/C piping that most people are running? Am I wrong in thinking that if I increase the size of the TB, that it will not make much of a difference, since the maximum amount of air can only pass through the smallest point of the intake system? I really do not have much in the way of experience in exactly how this will pan out, since most people are running a turbo that has, lets say a 2.5" outlet, along with 2.5" I/C piping. Something to think about before we jump into the bigger is always better idea.

Restrictions are cumulative. So it never hurts to remove one, even if there are still other's up or down stream. It'll at least remove that one contribution to pressure drop and restriction.

Key point is to identify the "largest restriction" and address it first... otherwise there are diminished returns. Kinda like how the k04 becomes the biggest restriction at a certain point, and every bolt on in the world won't make much of a difference in power... only lots of octane and very aggressive tunes.

Good shit Ant. Thanks for combining all the links and stuff in one concise thread

[SilverDemon]

Thanks for the charts skates.. I think there is something I/we are missing. Going by the references you supplied us with, it would stand to reason that 99% of the I/C kits that are sold are of the incorrect size on the cold side (at least for the BT applications). Maybe I need to re-evaluate my I/C set up to really understand what needs to happen.

Much more brainstorming in my future!! hahaha

[The Panda]

Im going to dig in this as well...

[SPEED6 KILLAH]

Here is the part number for the pigtail harness connector

[Erich]

I am not using the HEMI throttle body. Mine is off the 3.6 liter Jeep (also challenger, avenger, chrysler 200, etc.) and is part number 05184349ac. I believe the opening is 80mm and it tapers to 74mm at the plate.

[superskaterxes]

Originally Posted by Erich I am not using the HEMI throttle body. Mine is off the 3.6 liter Jeep (also challenger, avenger, chrysler 200, etc.) and is part number 05184349ac. I believe the opening is 80mm and it tapers to 74mm at the plate.

thanks for clarifying!

do u mean this one?

3.6L V6 Throttle Bodies - The Fastman

[djuosnteisn]

I just wanna throw my $.02 out there on the CFM stuff.

CFM is NOT = airflow. CFM is purely defined by the displacement of the motor, volumetric efficiency, and rpm.

Once you define things like the fluid (air), temperature, pressure (boost), etc of the medium... it becomes a mass flow (like g/s or lb/min).

The "CFM" in ant's above post are more likely airflows (dunno bout units)... considering they increased with higher boost. Real CFM won't change with boost, only the airflow will.

[SPEED6 KILLAH]

For the people who dont wanna go big can get a 66mm some one just need to make a spacer to center it out

[themytb]

Originally Posted by djuosnteisn Restrictions are cumulative. So it never hurts to remove one, even if there are still other's up or down stream. It'll at least remove that one contribution to pressure drop and restriction. Key point is to identify the "largest restriction" and address it first... otherwise there are diminished returns. Kinda like how the k04 becomes the biggest restriction at a certain point, and every bolt on in the world won't make much of a difference in power... only lots of octane and very aggressive tunes. Good shit Ant. Thanks for combining all the links and stuff in one concise thread

Damn it, I was all excited because I had something smart to say. You beat me to it haha.

[Erich]

Originally Posted by superskaterxes thanks for clarifying! do u mean this one? 3.6L V6 Throttle Bodies - The Fastman

No part number associated with that one so I can't say for sure. Just went out and took a picture of mine and measured it. Sorry for the crappy picture... trying to hit the iPhone soft button while holding it one handed at a weird angle while trying to hold the IC piping out of the way with the other hand was a pain. I Measured 79mm at the entrance, but it is likely 80, again a function of trying to get the calipers into an odd spot. (Wrong information.)

Edit: I was wrong. Not 80 74. Was in a hurry when I took the measurement and not paying close enough attention. My TB is in fact 74mm at the entrance (just measure it several times for accuracy). Sorry for the misinformation.

[MarkyMark]

As long as we get the AccessPort tables figured out for drivability, what's stopping me from making a larger throttle body from billet aluminum that accepts the factory gears/electronics?

[Erich]

See my last post for corrected information. My TB is not 80mm at the entrance it is 74. We had talked about some others, and tried two others (I don't have part numbers for the other two we tried, you would have to ask John but one of them was 80 tapering to 74) before deciding on this one. The other two we tried were never driven on, just wired in and checked for response.

[superskaterxes]

Originally Posted by StreetUnitMark As long as we get the AccessPort tables figured out for drivability, what's stopping me from making a larger throttle body from billet aluminum that accepts the factory gears/electronics?

it would have to be sub $150-200 cause thats the cost of the hemi TB and connector.

make it happen!!!!!!!

[redmnsterut]

Originally Posted by StreetUnitMark As long as we get the AccessPort tables figured out for drivability, what's stopping me from making a larger throttle body from billet aluminum that accepts the factory gears/electronics?

I say this! I started reading and got lost with all the numbers, but subbed for future awesomeness

[Erich]

Originally Posted by Lex Were they unable to port it further? I assume the remachined the throttle plate? Another thing to consider. If the ECU uses the throttle position to determine tip-in enrichments and idle which it does at least to some extent, changing the size dramatically will affect driveability and you may see the car behaving more abruptly during transitions. I would get in touch with COBB and ask about tip in enrichment tables as these will come into play here.

There are definitely rougher transitions on and off throttle. I was able to compensate for this some by flattening the APP Translation tables down low. The rest was adjusting driving style. Would still be nice to have the tables to properly account for the issue though.

[Dano]

Originally Posted by mrmonk7663 Good research. This effectively kills the cx9 72mm option. The hemi option is still in play, but at almost 3" it is somewhat "large" for mild turbos it would seem, bnr, 2871, etc. Surely there has to be other TBs in a 70mm range that could work.

As SS stated, the OE TB can support up to ~450WHP. That means a BNR S3 /2871 doesn't need an upgrade period and it would be arguable to upgrade for a GT/GTX3071.

larger TBs are for the big boys

[doubleflusher]

Originally Posted by StreetUnitMark As long as we get the AccessPort tables figured out for drivability, what's stopping me from making a larger throttle body from billet aluminum that accepts the factory gears/electronics?

Nothing, you sexy motherfucker.

[MarkyMark]

Originally Posted by superskaterxes it would have to be sub $150-200 cause thats the cost of the hemi TB and connector. make it happen!!!!!!!

I'll have to go measure the overall dims of the throttle body, but I'm thinking around 40-50 in material. Could be wrong. I'll add this to my list. Maybe I could get started soon, seems easy enough.

I'll have to add in the cost of fancy packaging though, so that's about $60 right there

Originally Posted by doubleflusher Nothing, you sexy motherfucker.

With this being said, if I can get something to incorporate stock hardware, where do i get this hardware from?

Core exchange program? I could reverse engineer the little parts, but that would drive the cost sky high.

I highly doubt the TB gears/electronics can be ordered separate from the body itself. @SPEED6 KILLAHwould know that.