Official ITB Reference Thread

[RYU]

With cars like Shawn's around I'm really quite envious of ITBs. It might still be in my future because it isn't always about performance. It's also about the drama. The sound... god the sound is intoxicating.

The only reason I have not gone to the dark side is due to the limitations of tuning almost exclusively via the TPS. I know enough about tuning that, for the way i drive my car, I don't want to be limited to a TPS dependent tune.

If someone builds a proper carbon airbox that is also appropriate and beautiful which can properly accommodate a MAP and IAT sensor I'm in!

 

[Ponyboy]

With cars like Shawn's around I'm really quite envious of ITBs. It might still be in my future because it isn't always about performance. It's also about the drama. The sound... god the sound is intoxicating.

The only reason I have not gone to the dark side is due to the limitations of tuning almost exclusively via the TPS. I know enough about tuning that, for the way i drive my car, I don't want to be limited to a TPS dependent tune.

If someone builds a proper carbon airbox that is also appropriate and beautiful which can properly accommodate a MAP and IAT sensor I'm in!

Thanks for the kind words, RYU. There is a dramatic aspect to the sound, feel, and experience of ITB induction but I rarely talk about it as the guys that emphasize power look at me like I'm speaking a foreign language. I have a MAF car with ITBs and I actually prefer the TPS solution. There's an inherent timing issue with MAF sensors reading the signal and the cylinder filling. But you know much more about the tuning aspect than I ever will.

My airbox is carbon with an engraved metal top. I forget the formula to determine the correct volume for an airbox but the shape is a significant factor in optimizing Helmholtz Resonances as well. IIRC, my airbox is a little on the small side but certainly useable.

 

[RYU]

Looks like there's hope for me yet!

 

[NA1/2-R GT]

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.

My engine has Bisimoto level 3 cams.
FI exhaust was built for Turbo/supercharged applications.

 

[Patricio]

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[MENTION=15180]NA1/2-R GT[/MENTION]

very impressive build
can u post your latest dyno?
I'm very interested in doing a similar build likely 12:1 or 12.5:1 to run e85
debating between 92mm bore on OEM cylinders (like many JDM builds) for 3111cc or darton MID sleeves with 95mm bore for 3317cc which was recommended by SOS and like factorX used to build.

another option is I have access to an OEM 3.2L engine & 6spd trans with only 20k miles, engine builder says with such extreme low of millage, we could just swap the higher compression pistons with no other engine work and leave the better flowing 3.2 head alone and just add cams springs ect.
Rather than porting 3.0 heads & sleeving block and replacing every bearing and rebuilding every part that generally goes along with working on a high millage block. may come out substantially less expensive with similar results to the ported 3.0 heads and 92mm bored or 95mm sleeved block

I'm still comparing options like the J35/J36 and reluctant to invest too much into sleeving or stroking the C due to parts availability and down time getting worse by the day.

350whp on 12:1 to 12.5:1 compression 3.2L with cams and e85 and ITB (or my manifold) should be sufficient for the low weight I'm at.

 

[ScienceofSpeed]

If someone builds a proper carbon airbox that is also appropriate and beautiful which can properly accommodate a MAP and IAT sensor I'm in!

We offer an airbox with intake sensor port (photo below). The MAP sensor can not be in the airbox, it needs to be behind the throttle blades. Our kit attaches the MAP sensor to the vacuum distribution block.
https://www.scienceofspeed.com/inde...eofspeed-individual-throttle-body-system.html

 

[RYU]

Chris (@ScienceofSpeed),Thanks for the reminder. You're right about the MAP sensor of course. Instead of putting 6 of them (one in each manifold after the butterfly) I was considering installing it in the Valve Body that controls the vacuum. Have you had any experience using this method or something similar?

We offer an airbox with intake sensor port (photo below). The MAP sensor can not be in the airbox, it needs to be behind the throttle blades. Our kit attaches the MAP sensor to the vacuum distribution block.https://www.scienceofspeed.com/inde...eofspeed-individual-throttle-body-system.html

 

[ScienceofSpeed]

Chris (@ScienceofSpeed),Thanks for the reminder. You're right about the MAP sensor of course. Instead of putting 6 of them (one in each manifold after the butterfly) I was considering installing it in the Valve Body that controls the vacuum. Have you had any experience using this method or something similar?

There is no reason to install 6. The 6 manifolds run in to the distribution manifold shown in the photo. This equalizes individual cylinder intake strokes so that the MAP sensor (which connects to the distribution manifold using the barbed fitting shown in the photo) will ready steady.

 

[RYU]

There is no reason to install 6. The 6 manifolds run in to the distribution manifold shown in the photo. This equalizes individual cylinder intake strokes so that the MAP sensor (which connects to the distribution manifold using the barbed fitting shown in the photo) will ready steady.

That's fantastic Chris. Thanks for confirming. [MENTION=4055]Ponyboy[/MENTION], any reason why you're not using the MAP sensor if, as Chris said, you can connect it to the vacuum manifold?

- - - Updated - - -

Shawn, I also saw you mentioned the MAF instead of the MAP. Did you mean MAP? I suppose it's easy enough to connect a MAF sensor in one of the throttle bodies. That's an interesting thought actually. I can see that connecting the MAP to the vacuum block might suffer from some lag or delay as you mentioned.

 

[Ponyboy]

Hey [MENTION=20915]RYU[/MENTION], I've miscommunicated, I think. I run the SOS ITB system which uses the MAP sensor. I just meant that I preferred tuning with a TPS over a MAF sensor(s). My M5 uses two MAF sensors and they have to be replaced every few years. That combined with their timing issue makes me believe that "tuning" via TPS is a better solution between the three main types (TPS, MAF, and Speed Density). But I'm not very knowledgable in the area and I realize that TPS tuning has just as many issues - it's just my .02.

My car's airbox is very similar in dimensions to what Chris posted but with the engraved "ScienceofSpeed" metal plate on top and the air filter in the stock location. IIRC, I have their pre-production air box.

 

[mr envy]

Thought I would show you guys my current setup I have just made it will run an air box that will seal against the bonnet so it looks a little naked. Have some short trumpets to go on just to finish them off. Will let you know how they go

 

[hkz286]

dayum! what car is the engine in?

 

[austrian type-R]

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[MENTION=15180]NA1/2-R GT[/MENTION]

very impressive build
can u post your latest dyno?
I'm very interested in doing a similar build likely 12:1 or 12.5:1 to run e85
debating between 92mm bore on OEM cylinders (like many JDM builds) for 3111cc or darton MID sleeves with 95mm bore for 3317cc which was recommended by SOS and like factorX used to build.

another option is I have access to an OEM 3.2L engine & 6spd trans with only 20k miles, engine builder says with such extreme low of millage, we could just swap the higher compression pistons with no other engine work and leave the better flowing 3.2 head alone and just add cams springs ect.
Rather than porting 3.0 heads & sleeving block and replacing every bearing and rebuilding every part that generally goes along with working on a high millage block. may come out substantially less expensive with similar results to the ported 3.0 heads and 92mm bored or 95mm sleeved block

What pistons could you run on the oem cylinder liner with the 3.2 engines? I think nobody found aftermarketpistons for it to rise the CR.

I will have soon a Golden Eagle sleeved block with brian crower stroker: 3,5 Liter. The GE sleevs are good for 93mm and a lot cheaper then the Darton MIDs (2500usd incl install, bore and hone). Sure you can not go that far with the GE than with the MIDs, but I got a realy good deal on the stroker kit, it was just used for one race and it comes with 93mm pistons. All the parts looks like new. I have to do this in that case for the cheap money I got the stuff, LOL!

Target: 450hp to the engine with ITBs or your IM. I also wanna try this monster thottle body from Comptech I bought used from a Prime memeber last week. If I have 400hp with a single TB on the modified oem Comptech IM, it is okay too to begin with.

 

[mr envy]

Sorry mine is in a rear wheel drive eg9 civic still a 4 seater

 

[whrdnsx]

Any Dyno numbers? They are Toyota 4AGE Throttle Bodies?

 

[Patricio]

[MENTION=9710]austrian type-R[/MENTION]
not sure which pistons yet, but I was under the impression compatibility with FRM had already been discovered by SOS or other honda engine builders.

seams you got your self a good deal on that engine, congrats! looking forward to the build
Ill keep you updated on my manifold release progress.

 

[mr envy]

No dyno numbers yet sorry but shouldn't be long until I have some results and comparisons

 

[NA1/2-R GT]

What pistons could you run on the oem cylinder liner with the 3.2 engines? I think nobody found aftermarketpistons for it to rise the CR.

I will have soon a Golden Eagle sleeved block with brian crower stroker: 3,5 Liter. The GE sleevs are good for 93mm and a lot cheaper then the Darton MIDs (2500usd incl install, bore and hone). Sure you can not go that far with the GE than with the MIDs, but I got a realy good deal on the stroker kit, it was just used for one race and it comes with 93mm pistons. All the parts looks like new. I have to do this in that case for the cheap money I got the stuff, LOL!

Target: 450hp to the engine with ITBs or your IM. I also wanna try this monster thottle body from Comptech I bought used from a Prime memeber last week. If I have 400hp with a single TB on the modified oem Comptech IM, it is okay too to begin with.

Benson Sleeves- 93mm (3.2L)
93mm 11.5:1 Compression CP Forged Pistons

 

[A_J]

Some ITB sound from a track far north

 

[TURBO2GO]

Damn you can really hear that Vtec shift with ITB's.

 

[Professor X]

We offer an airbox with intake sensor port (photo below). The MAP sensor can not be in the airbox, it needs to be behind the throttle blades. Our kit attaches the MAP sensor to the vacuum distribution block.
https://www.scienceofspeed.com/inde...eofspeed-individual-throttle-body-system.html

I'm very interested. Do you have additional pics of the box installed on a nsx? Let me know asap... THANKS

 

[kalsonc]

bump

wondering if anyone has ways to get mesh covers for their itb

 

[Rainman]

Is there any way to direct cold air to the air box?

 

[Honcho]

Is there any way to direct cold air to the air box?

The airbox already feeds cold air from the factory induction scoop located in the driver rear fender.

 

[Rainman]

The airbox already feeds cold air from the factory induction scoop located in the driver rear fender.

Not sure I understand. Is there a way to connect the itb box to the factory induction scoop.