Notices
General Miata Chat A place to talk about anything Miata

ITB setup opinions?

Thread Tools
 
Search this Thread
 
Old Apr 5, 2011 | 03:26 PM
  #81  
miata2fast's Avatar
Elite Member
iTrader: (2)
 
Joined: Aug 2009
Posts: 3,145
Total Cats: 175
From: Dover, FL
Default

Originally Posted by nitrodann
Lol, this will never go anywhere really. I have cams portwork solid lifters etc etc etc but i still have stock Im if that answers your question.

Dann
Wanna race?

If you have all that, you will go faster if you developed the induction. My personal opinion.

I never would have run what I do currently with a stock manny and throttle body.
Old Apr 5, 2011 | 03:38 PM
  #82  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

Originally Posted by WonTon
If you have ITBs that are 40mm, thats 160mm feeding the engine divided by 4. so technically you have the ability to feed more air into the engine and with short straight runners you get that supply faster.

you meant this:
Attached Thumbnails ITB setup opinions?-tps_vs_itb.jpg  
Old Apr 5, 2011 | 05:27 PM
  #83  
y8s's Avatar
y8s
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

individual throttle bodies plus a plenum > one throttle body in front of the plenum.

imagine having big *** ports at high rpm and teenie high velocity ports at low rpm? mmm sweeeeet.
Old Apr 5, 2011 | 06:03 PM
  #84  
WonTon's Avatar
Elite Member
iTrader: (17)
 
Joined: Apr 2009
Posts: 2,799
Total Cats: 1
From: Atlanta, GA
Default

Lets see if I can redeem myself! If your cruising at 3500 RPM, Thats about 58 Rotations per second, and about 116 strokes per second right? 2 strokes per rotation right? (Im rounding my numbers)

If you ask me, saying that one stroke pulling air through a 60mm TB is wrong givin the amount of air that can be pulled in the engine in ONE second depending on RPMs.
Old Apr 5, 2011 | 06:10 PM
  #85  
nitrodann's Avatar
Elite Member
 
Joined: Apr 2010
Posts: 2,826
Total Cats: 66
From: Newcastle, Australia
Default

Your cute.

Dann
Old Apr 5, 2011 | 06:18 PM
  #86  
WonTon's Avatar
Elite Member
iTrader: (17)
 
Joined: Apr 2009
Posts: 2,799
Total Cats: 1
From: Atlanta, GA
Default

Originally Posted by nitrodann
Your cute.

Dann
Old Apr 5, 2011 | 06:55 PM
  #87  
miata2fast's Avatar
Elite Member
iTrader: (2)
 
Joined: Aug 2009
Posts: 3,145
Total Cats: 175
From: Dover, FL
Default

Originally Posted by y8s
individual throttle bodies plus a plenum > one throttle body in front of the plenum.

imagine having big *** ports at high rpm and teenie high velocity ports at low rpm? mmm sweeeeet.
You bring up a very good point. The throttle body in front of the plenum is what will always cause a lower pressure inside a naturally aspirated intake tract than the air outside of the intake tract.

What do Indy Car, Prostock, and Moto GP all have in common? They are all unlimmited naturally aspirated racers, and they all have one throttle body per cylinder.

The only time I have seen a single throttle body in an unlimmited application, is turbo or supercharged drag cars. I think it is because the plenum has a pressure high enough to keep one runner from robbing another, and quick throttle response in not really important.......And I spend a lot of time at the drag strip.
Old Apr 5, 2011 | 07:01 PM
  #88  
thirdgen's Avatar
Thread Starter
Slowest Progress Ever
iTrader: (26)
 
Joined: Oct 2007
Posts: 6,029
Total Cats: 304
From: The coal ridden hills of Pennsylvania
Default

How much time do you spend driving your car down the street? I want to know about the daily driven characteristics of a setup like this. I under stand WOT performance, but what about cruising?
Old Apr 5, 2011 | 07:11 PM
  #89  
miata2fast's Avatar
Elite Member
iTrader: (2)
 
Joined: Aug 2009
Posts: 3,145
Total Cats: 175
From: Dover, FL
Default

I have found that cruising along on the street is great. I have had no drivability problems at all. When you crack the throttle it is way more responsive than stock. If you tune it correctly, you will be amazed at how hard it accelerates with part throttle. It make the experience quite nice.

It took a while to get rid of the dead spot when I floored it, but after fiddling with it, I got it to go away.
Old Apr 5, 2011 | 08:40 PM
  #90  
y8s's Avatar
y8s
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

Originally Posted by miata2fast
You bring up a very good point. The throttle body in front of the plenum is what will always cause a lower pressure inside a naturally aspirated intake tract than the air outside of the intake tract.

What do Indy Car, Prostock, and Moto GP all have in common? They are all unlimmited naturally aspirated racers, and they all have one throttle body per cylinder.

The only time I have seen a single throttle body in an unlimmited application, is turbo or supercharged drag cars. I think it is because the plenum has a pressure high enough to keep one runner from robbing another, and quick throttle response in not really important.......And I spend a lot of time at the drag strip.
but still

if you could

wouldn't you?

Old Apr 5, 2011 | 09:38 PM
  #91  
g_reichow's Avatar
Junior Member
iTrader: (2)
 
Joined: Nov 2010
Posts: 161
Total Cats: 0
From: NoVa
Default

y8s, whose manifold is that? more specifically, the plenum?

-Greer
Old Apr 5, 2011 | 10:05 PM
  #92  
y8s's Avatar
y8s
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

it's a k series setup from hayward.

for a couple grand, you could have one too.

http://www.haywardperformance.com/intake_systems.php
Old Apr 5, 2011 | 10:10 PM
  #93  
g_reichow's Avatar
Junior Member
iTrader: (2)
 
Joined: Nov 2010
Posts: 161
Total Cats: 0
From: NoVa
Default

Not that much love, was hoping for a solid plenum supplier besides ross machine

-Greer
Old Apr 5, 2011 | 10:32 PM
  #94  
90R's Avatar
90R
Junior Member
iTrader: (4)
 
Joined: Jul 2010
Posts: 278
Total Cats: 0
Default

Originally Posted by WonTon
Thats like saying they could have put a better intake on there or even a more free flowing exhaust. They cant cause they have to stick to certain standards. Im sure if they could have they would have slapped a begger displacement engine in there, but that would change the classing of the car. (Isnt there some kinda tax overseas based on your engine displacement?)
don't forget the lawyers and bean counters

Originally Posted by VitaminD
why would you spend all the money to set up ITB's when you could have a cheap satisfying turbo?


Originally Posted by thirdgen
Thanks a lot for your information.
My real big question comes with tuning. How would I tune an ITB setup with my MS2 which uses a MAP sensor? I would imagine the vacuum signal must be really sucky.
MS2 should have alpha N capability TPS/crank angle tuning and the "special" ITB stetting of blended speed density / alpha N

use a vacuum block to combine the 4 shitty signals into a somewhat useable single signal.
Old Apr 5, 2011 | 11:18 PM
  #95  
Savington's Avatar
Former Vendor
iTrader: (31)
 
Joined: Nov 2006
Posts: 15,442
Total Cats: 2,106
From: Sunnyvale, CA
Default

Originally Posted by miata2fast
If you put a vacuum gauge on a plenum of a normally aspirated car at WOT, is it going to be higher than the ambient outside air?
If you spend a LOT of time tuning runner lengths (intake and exhaust), port sizing/velocity, valve size/angle, and plenum size/design, you can get a motor with such good scavenging that it will produce positive manifold pressure. One of the S2000 motors (or both?) runs at more than 100% VE due to good tuning.

[/quoteI think that it helps alleviate the symptom tremendously, but does it truely completely eliminate it? [/quote]

Uh, yes. When the valve opens, you pull air from the plenum, which pulls from the throttle body (and now we're back to the 60mm vs. 40mm argument). The rest of the runners get the bouncing effect that Scooteroo was talking about.
Old Apr 5, 2011 | 11:22 PM
  #96  
Savington's Avatar
Former Vendor
iTrader: (31)
 
Joined: Nov 2006
Posts: 15,442
Total Cats: 2,106
From: Sunnyvale, CA
Default

Originally Posted by WonTon
Lets see if I can redeem myself! If your cruising at 3500 RPM, Thats about 58 Rotations per second, and about 116 strokes per second right? 2 strokes per rotation right? (Im rounding my numbers)

If you ask me, saying that one stroke pulling air through a 60mm TB is wrong givin the amount of air that can be pulled in the engine in ONE second depending on RPMs.
What the **** are you saying?
Old Apr 5, 2011 | 11:26 PM
  #97  
curly's Avatar
Cpt. Slow
iTrader: (25)
 
Joined: Oct 2005
Posts: 15,197
Total Cats: 1,398
From: Oregon City, OR
Default

We're going to add to our warning system. Not only will we have a grammar warning, but now WonTon will have a math warning.
Old Apr 5, 2011 | 11:44 PM
  #98  
nitrodann's Avatar
Elite Member
 
Joined: Apr 2010
Posts: 2,826
Total Cats: 66
From: Newcastle, Australia
Default

Originally Posted by thirdgen
How much time do you spend driving your car down the street? I want to know about the daily driven characteristics of a setup like this. I under stand WOT performance, but what about cruising?

I really dont think you do understand WOT performance.

Originally Posted by miata2fast
I have found that cruising along on the street is great. I have had no drivability problems at all. When you crack the throttle it is way more responsive than stock. If you tune it correctly, you will be amazed at how hard it accelerates with part throttle. It make the experience quite nice.

It took a while to get rid of the dead spot when I floored it, but after fiddling with it, I got it to go away.
I agree with everything that miata2fast just said, the only thing i would like to add to this is that due to the huge intake flow area you now have, a dyno plot would show that 3/4 throttle made equal or damn near close to WOT power, and also due to this huge intake flow area it might feel like only part throttle under your foot but I bet the vacuum is like 70 kpa when you think your only at 1/4 throttle, even more-so at lower rpm.

When 90R refers to alpha-n above hes refering to tuning with just tps and map as i explained earlier just to clarify to you. This is the setting you need to set MS (or any other ECU) to to run no map sensor input.

Dann
Old Apr 6, 2011 | 12:37 AM
  #99  
WonTon's Avatar
Elite Member
iTrader: (17)
 
Joined: Apr 2009
Posts: 2,799
Total Cats: 1
From: Atlanta, GA
Default

Originally Posted by Savington
What the **** are you saying?
I dont even know anymore.

I think what I was trying to get across is that one stroke is irrelevant to the grand picture. In one second an engine can take in more air than I can breath in a minute. Its like breathing through a straw. If you open up the airway it gets easier to pull in air.

Originally Posted by curly
We're going to add to our warning system. Not only will we have a grammar warning, but now WonTon will have a math warning.
okay, okay....no more math for me.

Atleast I think my math was right on the second try!
Old Apr 6, 2011 | 12:42 AM
  #100  
pusha's Avatar
Elite Member
iTrader: (5)
 
Joined: Nov 2009
Posts: 7,330
Total Cats: -29
From: Miami, FL
Default

Originally Posted by Pusha
If you want to be so different, just live under a ******* bridge.
I was warned for this post by curly, I believe this to be unjust. I stand by my original post and would like to add that the OP's reasons for starting this topic are retarded. You can't thread crap in a beshitted thread.

In case you missed his reasoning behind wanting ITBs:

" mean think about it. If you have a LS-1 camaro and you get beat by a turbo Miata...you'll be like, "that thing weighs 1/2 my car, and I don't have boost...let me boost my car, then we'll see who wins". However, if you beat me, but I still can hang with you, you might say, "that thing is pretty fast, but I didn't hear it blow off. What? It's Not Boosted??? That's pretty mean!"
ITB's change the whole power band. I have read that it's full throttle power from 3000-9000 RPM."



All times are GMT -4. The time now is 12:59 PM.