Multi Throttle Bodies vs Single Throttle Body - GT-R Register - Nissan Skyline and GT-R Drivers Club forum

Want to buy a banner ad? Find out more here.

Go Back   GT-R Register - Nissan Skyline and GT-R Drivers Club forum > General > Nissan Skyline > Tuning: General
Register Garage FAQ Members List Calendar Search Today's Posts Mark Forums Read Insurance


Like Tree23Likes

Reply
 
LinkBack Thread Tools Rate Thread Display Modes
Old 14th June 2015, 09:57 PM   #1 (permalink)
matt j is at Strawberry Racing
Following EJH#25
 
matt j's Avatar
 
Join Date: Oct 2001
Posts: 6,819
Multi Throttle Bodies vs Single Throttle Body

Hopefully a healthy discussion based upon facts and not opinions.

Quote:
When it comes to naturally aspirated and turbocharged vehicles alike, it is hard to beat the response and efficiency of individual throttle bodies. Unfortunately because manufacturers often tend to prioritize cost over Peak power, individual throttle bodies are a rare sight in factory equipped vehicles, and generally limited only to the highest performing models such as the BMW M3 and Nissan Skyline. When cost is no object however, individual throttle bodies have several distinct advantages over their single throttle body counterparts.

Single Throttle Bodies

Most vehicles come from the factory with a single throttle body primarily due to cost concerns, as individual throttle bodies tend to be far more costly and contain far more individual parts. In a single throttle body design, air rushes into the intake manifoldís plenum when the throttle is opened. While the response is relatively quick, there is still a brief pause between the time the air rushes into and fills the plenum, and when it actually runs into each cylinder. No matter how well tuned the engine is, or how balanced and blueprinted its components are, this lag will always be present, however miniscule.

Individual Throttle Bodies

In a vehicle equipped with individual throttle bodies, the plenum if equipped, remains full of air whether the throttle is open or closed. Because of this pre-filled state, there is no wait when the throttle is opened, and air rushes directly into the engine, resulting in a crisp and responsive throttle. In some extensively modified, naturally aspirated engines, the plenum may be removed altogether, allowing room for tuned velocity stacks designed to compliment a specific power curve and make more useable power. In high horsepower engines, individual throttle bodies also tend to flow air more efficiently, freeing up power and complimenting high lift cams or high levels of boost.
Physics dictate the above which is a given, there is no possible argument there.
So on to the concerns...

Quote:
Potential Concerns

Individual throttle bodies, when run without a plenum may be more susceptible to dirt and dust and excessively loud for street use. These engines should not be operated in areas of excessive dust and dirt without adequate filtration. It should be noted that for vehicles equipped with mass air flow sensors, a sealed intake system will be required for proper operation, as is the case with Nissanís RB26DETT engine, which is equipped with a standard plenum style intake manifold equipped with individual throttle bodies. Individual throttle body kits are generally very expensive due to the precision and machining required. Often at times as much as 3-6x more than a comparable single throttle body upgrade. Because of the limited power increases they may make with an otherwise stock engine, they are often times better suited as a finishing touch rather than a starting point.

The power your engine can generate can be limited by restrictions and inefficiencies. At stock power levels, these restrictions may not be apparent. But in a highly tuned engine, they can become severe bottle necks to airflow, and thus largely reduce power. Individual throttle bodies not only offer superior response, but they also reduce these restrictions, freeing up power through improved airflow, with little to no trade off other than cost and increased engine noise.
So at what point does a single throttle body become more efficient than individual throttle bodies?
GTRNICK and FRRACER like this.
__________________
matt j is offline   Reply With Quote
Old 14th June 2015, 10:08 PM   #2 (permalink)
TAZZMAXX is ...............
ADMIN
 
TAZZMAXX's Avatar
 
Join Date: Mar 2010
Posts: 13,345
Where's Dan? I'm sure he'll soon clear this up for you Matt
__________________
Ambition is the last refuge of failure
TAZZMAXX is offline   Reply With Quote
Old 14th June 2015, 10:10 PM   #3 (permalink)
matt j is at Strawberry Racing
Following EJH#25
 
matt j's Avatar
 
Join Date: Oct 2001
Posts: 6,819
Quote:
Originally Posted by TAZZMAXX View Post
Where's Dan? I'm sure he'll soon clear this up for you Matt
That's the idea Tazz, saves commenting on other peoples threads and hopefully gets a good discussion, not just joe blogs told me so.
__________________
matt j is offline   Reply With Quote
 
Old 14th June 2015, 10:15 PM   #4 (permalink)
tath is aware they can edit their status but doesn't care
GTR.co.uk seasoned Member
 
tath's Avatar
 
Join Date: Jun 2005
Location: North West
Cars owned: R33 GTR, E36 M3
Posts: 212
A single TB is never better, it's just cheaper.

I think the ITBs on an RB is overkill tbh though, I doubt it makes a noticeable difference. On a FI engine it's just going to give you a bit extra response to dynamic loads.
__________________
perfututum est
tath is offline   Reply With Quote
Old 14th June 2015, 10:17 PM   #5 (permalink)
TAZZMAXX is ...............
ADMIN
 
TAZZMAXX's Avatar
 
Join Date: Mar 2010
Posts: 13,345
It's a good discussion point but is there any documented evidence for either option? Even if there is, there will always be advocates of both. It's a bit like the 4 valves per cylinder vs 2 valves per cylinder argument, both have their followers and they will never be swayed by the arguments of the other side.

Let's see what this thread turns up.
__________________
Ambition is the last refuge of failure
TAZZMAXX is offline   Reply With Quote
Old 14th June 2015, 10:32 PM   #6 (permalink)
matt j is at Strawberry Racing
Following EJH#25
 
matt j's Avatar
 
Join Date: Oct 2001
Posts: 6,819
No, I'm led to believe that there is real life evidence to support this Tazz, although I'm yet to see it. I keep getting told that the efficiency of the single is better (possibly at WOT, I'd like to see evidence) and that the standard multiple throttle bodies cannot support large power applications.

Well, I can kind of counter that as my car makes more power on the standard throttle bodies than some running singles, so as I've not yet reached the point where the standards are creating the restriction, I'd like to see what makes people think they need to downgrade to a cheaper alternative.
__________________
matt j is offline   Reply With Quote
Old 14th June 2015, 10:47 PM   #7 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
Matt I spoke to pete at hypertune about multi tb and single and he said he would remove the restrictive multi tb on any rb26 over 400hp now hypertune are classed as the best in the business all over the world. Considering the sell multi tb plenums and singles do you think the have a reason to talk people into singles?


That backed up with what amt have shown in flow charts should be enough to convince any one.

Last year I had multis now I have a single bearing in mind mine is 100mm so more focused on drag than circuit/road. What I can tell you is my engine now naturally revs ALOT faster I don't mean high rpm I mean from 1k rpm onwards.

The down side to a single is they are a little touchy meaning light throttle movements mean you gain more rpm faster but I personally like this and don't find it a problem at all and only noticed between 1-2k rpm.

High octane even fitted a 90mm tb and plenum to there r34 gtr twin turbo track car, now why would they have done that if multis are better and hypertune would have supplied them what ever they wanted?
__________________
Dan ep3 turbo is offline   Reply With Quote
Old 14th June 2015, 11:01 PM   #8 (permalink)
matt j is at Strawberry Racing
Following EJH#25
 
matt j's Avatar
 
Join Date: Oct 2001
Posts: 6,819
Quote:
Originally Posted by Dan ep3 turbo View Post
Matt I spoke to pete at hypertune about multi tb and single and he said he would remove the restrictive multi tb on any rb26 over 400hp now hypertune are classed as the best in the business all over the world. Considering the sell multi tb plenums and singles do you think the have a reason to talk people into singles?
Being serious here and not intended as a dig at all but as they're far cheaper to manufacture, I presume profit margins are greater and a good sales pitch.

Quote:
Originally Posted by Dan ep3 turbo View Post
That backed up with what amt have shown in flow charts should be enough to convince any one.
What dimensions; stock against 90mm, 100mm etc?

Quote:
Originally Posted by Dan ep3 turbo View Post
Last year I had multis now I have a single bearing in mind mine is 100mm so more focused on drag than circuit/road. What I can tell you is my engine now naturally revs ALOT faster I don't mean high rpm I mean from 1k rpm onwards.
You mean you have a less linear throttle control and it feels like it revs faster?
You actually have more lag but coarser control, as I see it.

Quote:
Originally Posted by Dan ep3 turbo View Post
The down side to a single is they are a little touchy meaning light throttle movements mean you gain more rpm faster but I personally like this and don't find it a problem at all and only noticed between 1-2k rpm.
You've just answered the question above.

Quote:
Originally Posted by Dan ep3 turbo View Post
High octane even fitted a 90mm tb and plenum to there r34 gtr twin turbo track car, now why would they have done that if multis are better and hypertune would have supplied them what ever they wanted?
I don't know the car Dan but I can think of several reason just off the top of my head why you would do it to a track car and not road car;
Weight
Mechanical complexity
Throttle control
Cost

The question you omitted is; at what point do the standard TBs become restrictive to warrant changing?
FRRACER likes this.
__________________
matt j is offline   Reply With Quote
Old 14th June 2015, 11:03 PM   #9 (permalink)
tarmac terror is Wondering why it says 'New User' below.....*confused*
New Users
 
tarmac terror's Avatar
 
Join Date: Jul 2003
Location: Hampshire, but Scottish through and through!
Cars owned: Genuine R32 GTR; Genuine-ish X5 4.8iS; Completely fake BMW M6; Reasonably Genuine Peugeot 306 Rallye
Posts: 8,540
Easiest way to find out is to take a highly modded engine and run it up on ITB's then swap over to a single and get some figures in that config.

With a bit of decent data logging you could quite easily get conclusive results...



TT
matt j, Dan ep3 turbo and bigal23 like this.
__________________
R32GTR- Stage 6; Frank Baxter exhaust with K-pipe; Rick Astley cams; Dave Gahan electrics; Bjorn Ulvaeus race prep; Howard Jones gearbox upgrade; Ray Charles body mods and styling. Mapped by Glenn Medeiros.------> Beat that R35 owners with dodgy parts list sigs :)
tarmac terror is offline   Reply With Quote
Old 14th June 2015, 11:18 PM   #10 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
Quote:
Originally Posted by matt j View Post
Being serious here and not intended as a dig at all but as they're far cheaper to manufacture, I presume profit margins are greater and a good sales pitch.


What dimensions; stock against 90mm, 100mm etc?


You mean you have a less linear throttle control and it feels like it revs faster?
You actually have more lag but coarser control, as I see it.


You've just answered the question above.


I don't know the car Dan but I can think of several reason just off the top of my head why you would do it to a track car and not road car;
Weight
Mechanical complexity
Throttle control
Cost

The question you omitted is; at what point do the standard TBs become restrictive to warrant changing?


There multi tb plenum are cheaper and have less work involved to make Matt so that can't be the case.

I no your not having a dig and I'm not at you but why would I or any ones else think what your saying is correct over a specialist like hypertune? You simple can't and don't no as much as them about inlet manifolds Matt.

It's nothing to do with coarser control romain could tell even remotely connected to my ecu.

ive had both Matt so I no the differences have you?
__________________
Dan ep3 turbo is offline   Reply With Quote
Old 14th June 2015, 11:21 PM   #11 (permalink)
Jayman is Owner of R34 GTR 720 hp
GTR.co.uk seasoned Member
 
Join Date: Jun 2012
Location: North Yorkshire
Posts: 924
il be keeping a close eye on this thread as i have just bought some NAPREC 50mm ITBS for my R34 GTR instead of going single.. but i am always open to change
__________________
Jayman is offline   Reply With Quote
Old 14th June 2015, 11:22 PM   #12 (permalink)
FRRACER is unaware they can edit their status
GTR.co.uk seasoned Member
 
FRRACER's Avatar
 
Join Date: Jun 2013
Cars owned: R32.4.5
Posts: 9,668
Similar discussion here talking about the benefits of multiple throttle bodies.

Personally I would stick to throttle bodies the benefits mentioned above suits what I look for in the way my RB engine drives on the road.

Saying that on my Formula Renault it has a single 65mm iirc throttle body. Two different engines so no comparison but it is fed with fresh air from the scoop and then down through the plenum through the air filter and into the engine. As far as response goes it's pretty crap low down and only and we always keep to the power band from around 4800-7250rpm. As far as I can remember F3 uses throttle bodies but totally different engine and concept as these are spec race engines.
Attached Images
File Type: jpg image.jpg (343.7 KB, 17 views)
__________________

Last edited by FRRACER; 14th June 2015 at 11:32 PM..
FRRACER is offline   Reply With Quote
Old 14th June 2015, 11:36 PM   #13 (permalink)
matt j is at Strawberry Racing
Following EJH#25
 
matt j's Avatar
 
Join Date: Oct 2001
Posts: 6,819
Quote:
Originally Posted by Dan ep3 turbo View Post
There multi tb plenum are cheaper and have less work involved to make Matt so that can't be the case.
Can you post link to the prices Dan?

Quote:
Originally Posted by Dan ep3 turbo View Post
I no your not having a dig and I'm not at you but why would I or any ones else think what your saying is correct over a specialist like hypertune?
But I'm not saying I'm correct Dan, I've posted what is commonly known in the industry. You are arguing against the original post, all I'm doing is asking for proof of why you think one application is better than the other. So far, all you've returned is just opinions.

Quote:
Originally Posted by Dan ep3 turbo View Post
You simple can't and don't no as much as them about inlet manifolds Matt.
Again, I'm not claiming to know anything Dan, I'm asking you to prove why you constantly go on about singles being better. All you've posted so far is because 2 people told you so. Do you have any evidence?

Quote:
Originally Posted by Dan ep3 turbo View Post
It's nothing to do with coarser control romain could tell even remotely connected to my ecu.
By looking at the TPS and revs?

Quote:
Originally Posted by Dan ep3 turbo View Post
ive had both Matt so I no the differences have you?
No Dan, I haven't mate, I'm not claiming I have. I've witnessed back-to-back testing though, albeit a few years ago and on a drag car that had a lot of power.
FRRACER likes this.
__________________
matt j is offline   Reply With Quote
Old 15th June 2015, 05:41 AM   #14 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
Quote:
Originally Posted by matt j View Post
Can you post link to the prices Dan?


But I'm not saying I'm correct Dan, I've posted what is commonly known in the industry. You are arguing against the original post, all I'm doing is asking for proof of why you think one application is better than the other. So far, all you've returned is just opinions.


Again, I'm not claiming to know anything Dan, I'm asking you to prove why you constantly go on about singles being better. All you've posted so far is because 2 people told you so. Do you have any evidence?


By looking at the TPS and revs?


No Dan, I haven't mate, I'm not claiming I have. I've witnessed back-to-back testing though, albeit a few years ago and on a drag car that had a lot of power.

You no why Matt cause the multi tbs restrict flow, amt showed every one years ago.

What plenums were tested back to back? From all the searches I done on forum I found a lot from twenierob saying the best all rounder was a endless single ?

Hypertune RB26 Multi Throttle Body Inlet Manifold - Garage Whifbitz

Hypertune RB26 Inlet Manifold For 90mm Throttle Body 6 Injectors - Garage Whifbitz

Also have to add £400 to the single plenum for throttle body
__________________
Dan ep3 turbo is offline   Reply With Quote
Old 15th June 2015, 05:48 AM   #15 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
The main reason I went to single plenum is I wanted to free up some power and if it ment I could run a smaller turbo to get the power I wanted easier then I would gain more response. Hence why I have got a 67mm turbo, as you no Matt dyno numbers don't mean much there's so many fake numbers there's no way cars performance can be compared on a sheet of paper. The only way is time weather it be a 30-130 time or 1/4 mile
__________________
Dan ep3 turbo is offline   Reply With Quote
Old 15th June 2015, 06:06 AM   #16 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
Quote:
Originally Posted by Jayman View Post
il be keeping a close eye on this thread as i have just bought some NAPREC 50mm ITBS for my R34 GTR instead of going single.. but i am always open to change

Have you got the new naprec hypertune plenum?
__________________
Dan ep3 turbo is offline   Reply With Quote
Old 15th June 2015, 06:27 AM   #17 (permalink)
matt j is at Strawberry Racing
Following EJH#25
 
matt j's Avatar
 
Join Date: Oct 2001
Posts: 6,819
Quote:
Originally Posted by Dan ep3 turbo View Post
You no why Matt cause the multi tbs restrict flow, amt showed every one years ago.
AT what power do they become so restrictive that only a single TB will be more efficient?

Quote:
Originally Posted by Dan ep3 turbo View Post
What plenums were tested back to back? From all the searches I done on forum I found a lot from twenierob saying the best all rounder was a endless single ?
Plenums? This thread is about TBs Dan.

Quote:
Originally Posted by Dan ep3 turbo View Post
Also have to add £400 to the single plenum for throttle body
And how much for uprated ITBs?

Quote:
Originally Posted by Dan ep3 turbo View Post
The main reason I went to single plenum is I wanted to free up some power and if it ment I could run a smaller turbo to get the power I wanted easier then I would gain more response.
Unless I'm mistaken, I run a single plenum too, I have seen multi plenum designs in the past but only in design.

Quote:
Originally Posted by Dan ep3 turbo View Post
Hence why I have got a 67mm turbo, as you no Matt dyno numbers don't mean much there's so many fake numbers there's no way cars performance can be compared on a sheet of paper. The only way is time weather it be a 30-130 time or 1/4 mile
30-130 would be easier for you, unless you intend on changing your suspension and new wheels/tyres for 1/4 you won't get the traction (at Elvington). Look at Rich at TOTB, good terminal, not so good ET. By your logic Rich should have been running 9s all day long with his power.

You're still just going by opinions so here's another couple of questions to add.

Do you know the control characteristics of butterfly valves?
Have you gone for DBW linear control?

Here's a clue as to why you think your response is better.
__________________
matt j is offline   Reply With Quote
Old 15th June 2015, 06:42 AM   #18 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
Matt your asking me questions I don't no and don't need to no.

All I'm doing is giving you reasons why I chose a single tb, why don't you give hypertune a email tell them your aiming for 1300bhp and ask them what they reccomend I'm sure they will be able to answer all your questions.

Hypertune said multi tb become very restrictive at 400hp.

Rich at amt had 750bhp at the flywheel and crap old road tyres he also had 19" wheels.

Considering I have 50hp more and better tyres if say I'd be a low 10 high 9.peak power doesn't mean a great deal Matt its the area under the curve what makes a car fast.

I'm going to do a Santa pod trip and run my car see what it does
__________________
Dan ep3 turbo is offline   Reply With Quote
Old 15th June 2015, 06:44 AM   #19 (permalink)
FRRACER is unaware they can edit their status
GTR.co.uk seasoned Member
 
FRRACER's Avatar
 
Join Date: Jun 2013
Cars owned: R32.4.5
Posts: 9,668
I am not convinced that the single offers any more benefit the inlet to the std plenum is what 80mm? that volume of air that can enter and always have a constant pressure regardless of what level of opening is on the ITB. On a single your still feeding through an 80mm pipe into 90mm throttle which then controls the air in through the plenum and into the cylinders if anything I can only see disadvantages and none of the advantages unless there is some proper data from the same engine with just those two differences ITB and a Single plenty setup.

I will be going down the Nismo plenum route at some point in my search for optimisation and get rid of the issues with the Oem plenum air flow design.

I think those who say single throttle is better is based on their own personal opinions and views. Would have been far cheaper for Nissan to have carried over a single plenum from the RB25 no? They clearly saw a benefit. In the after market work it would be far more expensive to develop a improved design or even larger ITB setup so people come out with a single which is easier and cheaper and something they can sell.
__________________

Last edited by FRRACER; 15th June 2015 at 06:49 AM..
FRRACER is offline   Reply With Quote
Old 15th June 2015, 06:49 AM   #20 (permalink)
Dan ep3 turbo is unaware they can edit their status
GTR.co.uk seasoned Member
 
Dan ep3 turbo's Avatar
 
Join Date: Sep 2013
Posts: 2,303
Quote:
Originally Posted by FRRACER View Post
I am not convinced that the single offers any more benefit the inlet to the std plenum is what 80mm? that volume of air that can enter and always have a constant pressure regardless of what level of opening is on the ITB. One a single you still feeding through an 80mm pipe into 90mm throttle which then controls the air in through the plenum and into the cylinders if anything I can only see disadvantages and none of the advantages unless there is some proper data from the same engine with just those two differences ITB and a Single plenty setup.

I will be going down the Nismo plenum route at some point in my search for optimisation and get rid of the issues with the Oem plenum air flow design.

I think those who say single throttle is better is based on their own personal opinions and views. Would have been far cheaper for Nissan to have carried over a single plenum from the RB25 no? They clearly saw a benefit. In the after market work it would be far more expensive to develop a improved design or even larger ITB setup.

Your forgetting that every cylinder isn't drawing 100% air at all times. Why don't you email the like of hypertune tell them there wrong I'm sure your theory would mean a lot to them. You havnt mentioned anything about the flow drop you get with itbs on the rb26 if this wasn't the case then yes it would be pointless removing the itb but it does that's why they need to be removed.


Come on people don't you think hypertune no everything about making plenums for the rb26 all there doing is advising people the best way they have seen to work
__________________

Last edited by Dan ep3 turbo; 15th June 2015 at 07:26 AM..
Dan ep3 turbo is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT. The time now is 08:47 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
http://www.Tyreforums.com

tyreforums

 

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.