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Official ITB Reference Thread

This brings me back to when I visited you guys in SoCal :) Can't believe I got to see and experience those cars back to back!
 
Thought i'd chime in with an update on IAT's now that I have a scoop on my roof (The SOS).

With an ambient air temperature of 50 degree's outside, my IAT reading reached 77 at idle after sitting for 10 minutes warming up.

After about 3 miles of driving, the IAT was showing a 53 degree intake temperature. I am pretty happy with this for so little invested.

The ITB's are coming off my street car and moving to my N/A car with 11.8:1 compression. I'll let you know the results!
 
Looks like PhonyBoy may have a solution to air box -> http://honda-tech.com/acura-nsx-43/sweet-air-box-3187009/
It also looks like the setup is using a DF air filter.

I resemble that remark. ;)

FWIW, I kept the SOS box, got rid of the open cone filter, installed the factory airbox, and ducted tubing from the SOS box to the stock airbox. Looks much better and IATs went way down. Ideally, I'd like to make the SOS box twice as big alá the '95 LeMans car so that the trumpets aren't cannabilizing air from each other.
 
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IT was build by an costumer of mine, but then he decided to set back his NSX to stock and now he has sold the car and all the goodies.

Here is a ITB powered S2000 with NSX engine and full race trim. Dynoed at 395hp to the engine with 3.0i, Toda cams, dry sump, standalone ecu, head-job, 11.5:1 pistons, Toda valve train, etc.

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^^ Sick! E85?

We just redyno'd mine at 298whp(dynapack) and 323whp(dynojet) with 12:1 compression and ITB's (no cams or headwork) on 91 octane at.... 7100rpm. Exhaust restriction :( Holds the power all the way out to 8300rpm. Need to get the exhaust opened up a bit!
Still a 3.0L

RYU regarding the IAT location, it is in the side of my previously pictured airbox, right between cylinders 5 and 6's horns.
 
What exhaust diameter are you running right now? Are you running headers? Do you think you may need headers with better flow?
 
Can any of you guys share you're locating the IAT sensor? integrals mentioned he has his mounted on the airbox. What if you're running just the horns and no airbox? Anyone have theirs mounted on one of the intake manifolds? There's no plenum so it seems mounting an IAT sensor would be very difficult.

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Also, how has the noise been? Is it livable for street/hwy driving? It must be super loud @ WOT but how about partial throttle? Is it a big difference in dB with or without an air box?

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More questions... [MENTION=4799]DDozier[/MENTION] would love to hear your thoughts here. What are you doing to measure air flow/volume going into the intake? What happened to the map sensor? Do you have one for each cylinder? Is your ems ignoring the map? Maybe you're using a maf? I just don't see a way to properly tune with a maf in an itb setup but please prove me wrong.
 
dang I wish we had that here! 93 is uncommon, let alone 95 or better!

I hope to hit 350whp with cams!

You have to differ between ROZ, MOZ, RON, MON and AON octane. ROZ and MOZ are the DIN names so abbreviations for german words. ROZ equals RON and MOZ equals MON in english.
RON = Research octane Number
MON = Motor octane Number
What you get in the US is AON (average octane number) or AKI (anti knock index) which is both the same. Its the average of RON and MON. MON is lower than RON and thats why your numbers a lower than ours. Our fuel is sold by ROZ(RON) numbers. What really counts for reduction of detonation is MOZ(MON) but nobody seems to bother.

For example:
Our 98 and 100 ROZ Octane premium fuel has 88 MOZ

98+88 decided by 2 is 93. So this fuel is equivalent to 93 AON.
100 ROZ + 88 MOZ decided by 2 would result in 94 AON.

But whats significantly different is the quality of the fuel. Also the quality is consistent as it comes from one big refinery for the most parts of Austria and surrounding countries. You rarely see dirt in fuel system related issues here.

Bernhard
 
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Can any of you guys share you're locating the IAT sensor? integrals mentioned he has his mounted on the airbox. What if you're running just the horns and no airbox? Anyone have theirs mounted on one of the intake manifolds? There's no plenum so it seems mounting an IAT sensor would be very difficult.

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Also, how has the noise been? Is it livable for street/hwy driving? It must be super loud @ WOT but how about partial throttle? Is it a big difference in dB with or without an air box?

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More questions... @DDozier would love to hear your thoughts here. What are you doing to measure air flow/volume going into the intake? What happened to the map sensor? Do you have one for each cylinder? Is your ems ignoring the map? Maybe you're using a maf? I just don't see a way to properly tune with a maf in an itb setup but please prove me wrong.

I would imagine mounting it IN the TB would result in fairly quick heat soaking issues.

As far as MAP, my setup at least uses RPM vs TPS vs o2 feedback with MAP as a backup in the event of TPS fail.

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You have to differ between ROZ, MOZ, RON, MON and AON octane. ROZ and MOZ are the DIN names so abbreviations for german words. ROZ equals RON and MOZ equals MON in english.
RON = Research octane Number
MON = Motor octane Number
What you get in the US is AON (average octane number) or AKI (anti knock index) which is both the same. Its the average of RON and MON. MON is lower than RON and thats why your numbers a lower than ours. Our fuel is sold by ROZ(RON) numbers. What really counts for reduction of detonation is MOZ(MON) but nobody seems to bother.

For example:
Our 98 and 100 ROZ Octane premium fuel has 88 MOZ

98+88 decided by 2 is 93. So this fuel is equivalent to 93 AON.
100 ROZ + 88 MOZ decided by 2 would result in 94 AON.

But whats significantly different is the quality of the fuel. Also the quality is consistent as it comes from one big refinery for the most parts of Austria and surrounding countries. You rarely see dirt in fuel system related issues here.

Bernhard

Correct, I didn't notice your location :) Very familar with the differences. In my area we CAN get AON 93 and 95 at the gas station but it is RARE and only in certain states. So I am usually limited to 91 for the sake of not carrying gallons of fuel with me for out of state track days etc.

E85 is the next move as it is readily available in most areas.
 
Add me to the list! My IAC Valve isn't working so having issues while idling with a load (AC on) and cold start. Other than that, drive beautifully, power delivery is smooth, the sound is intoxicating!

Engine: 3.0L
ITB Kit: Science of Speed 48MM
Supporting Modifications: Pride Header, Pride High Flow CATS, Pride V1 Exhaust, Injector Dynamics 725cc, AEM Series II
Tuner: KL Racing Development
Fuel: 91 octane
Results 286hp / 214 ftlb
Misc: 173,xxx miles.
Dyno Plot: Attached

Video: https://www.youtube.com/watch?v=SLwINgmau2s

View attachment 126855View attachment 126856
 
^^ Sick! E85?

We just redyno'd mine at 298whp(dynapack) and 323whp(dynojet) with 12:1 compression and ITB's (no cams or headwork) on 91 octane at.... 7100rpm. Exhaust restriction :( Holds the power all the way out to 8300rpm. Need to get the exhaust opened up a bit!
Still a 3.0L

RYU regarding the IAT location, it is in the side of my previously pictured airbox, right between cylinders 5 and 6's horns.
[MENTION=23308]integrals[/MENTION] have a dyno sheet?
 
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@integrals have a dyno sheet?

I have one of it doing 307whp in Cali at the NASA Nationals on this same setup. I'll see if I can dig it up!

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This was my ST2 dyno, which was flatlined tuned for classing reasons (310whp was my max at my weight). Was dyno'd in Mazda Speedway!
 

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That's impressive! Did you have any knocking problems running that compression on 91 octane (especially making 323whp)?

Do you have a chart of your 323whp, non-class specific/flat out pull?
 
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Emailed!

Sorry no charts of the outright tune. Although that will probably change shortly with this year :) Going for more power!

Knock wise, nope, not running a ton of timing honestly. E85 is a possibility now that I have a truck and trailer to haul everything around with!

Wish me luck in GTA this year! Won the ST2 class regionally last year and finished 8th at nationals instead of 16th where I qualified lol
 
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Bottom End (3.2L)
Benson Sleeves- 93mm (3.2L) Sleeves are good for multiple rebuilds if you need to bore the cylinders out more. Sleeves are good to go turbo as well.
93mm 11.5:1 Compression CP Forged Pistons
Factory rod/Crank- (micropolish and balanced)
ARP Rod bolts
Billet oil pump gears
Oil pan baffle
ATI Harmonic Balancer (Crank Pulley)
New Water Pump
Cedar Ridge Locking Timing belt Tensioner
Power Enterprises Super Kevlar II Timing belt

Heads (Endyn CNC Ported)
ARP Head Studs
MLS Head Gasket
Endyn CNC Ported Heads
Port and Polished Heads
SuperTech Dual Valve Springs
TI retainers
Racing Valves --nitride coated (1mm larger Intake Valves)
Harden split locks
Chromoly Spring Seats
Bronze Valve Guides- Hone- Fitted
Bisimoto level 3 cams
CT Engineering Adjustable Cam gears

Fuel & Intake
52mm Jenvey Individual Throttle Bodies
Injector Dynamics 675cc Injectors
Aeromotive Fuel Filter
-6 AN fuel Lines (black)
Walbro 255 Fuel Pump

Exhaust:
LoveFab FI-Spect Headers
LoveFab FI-SC Exhaust system 3" with Burns Stainless Muffler
 
So awesome! Did you guys do any tuning of the Cam gears?
Bottom End (3.2L)Benson Sleeves- 93mm (3.2L) Sleeves are good for multiple rebuilds if you need to bore the cylinders out more. Sleeves are good to go turbo as well. 93mm 11.5:1 Compression CP Forged PistonsFactory rod/Crank- (micropolish and balanced)ARP Rod boltsBillet oil pump gearsOil pan baffleATI Harmonic Balancer (Crank Pulley)New Water PumpCedar Ridge Locking Timing belt TensionerPower Enterprises Super Kevlar II Timing beltHeads (Endyn CNC Ported)ARP Head StudsMLS Head GasketEndyn CNC Ported HeadsPort and Polished HeadsSuperTech Dual Valve SpringsTI retainersRacing Valves --nitride coated (1mm larger Intake Valves)Harden split locksChromoly Spring SeatsBronze Valve Guides- Hone- FittedBisimoto level 3 camsCT Engineering Adjustable Cam gearsFuel & Intake52mm Jenvey Individual Throttle BodiesInjector Dynamics 675cc InjectorsAeromotive Fuel Filter-6 AN fuel Lines (black)Walbro 255 Fuel PumpExhaust: LoveFab FI-Spect HeadersLoveFab FI-SC Exhaust system 3" with Burns Stainless Muffler
 
Is this LoveFab Exhaust system made for forced induction? Or does that FI mean something else? I see you run Supertech valve springs, I have them too. You run the stock cams and use stiffer valve springs?

What do you guys think on using ITBs on stock or near stock engines? I think it is not much worth it, the tuning, the more gas consuption for just 15-20whp? IMO high lift cams and 11.5:1 or more CR is needed, then the next step are ITBs. I see 2 NSX here in Europe only doing 25 engine hp more than cars with stock intake. Thats not the best thing for the value.
 
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