[MineCowMcGee]

Yes, I know it's silly, a large waste of money, and I probably won't make any power and they won't fit ect. But I'm getting a great deal on some 4A 20v ITBs and the man selling them to me offered to make a manifold adapter for the price of parts. I couldn't find any concrete information on google, so I wanted to ask if anyone was running 1ZZ ITBs, and how its gone for them, what management to use, ect. I assume it's going to have to be a closed setup so I can use the stock MAF. I have no problem cutting up the firewall, the car is mainly used for track/autox. I completely understand it's a waste of money. But that's the whole point of a fun car, right?

 

[Funnyman]

With ITB, the MAF become useless and you need :
--- individual throttle body
--- specific fuel rail
--- throttle body angle sensor
--- MAP sensor (measuring pressure)
--- air temp sensor
--- welding wiring
--- standalone

One of the most difficult part is to calculate the right dimensions of the throttle body function of various parameters. It's not just 4 aluminium tubes and let's go.
Even if the 1ZZ-FE make power until 6800 rpms after tuned Standalone, the engine is mainly made for mid range and not high revs.

 

[MineCowMcGee]

With ITB, the MAF become useless and you need :
--- individual throttle body
--- specific fuel rail
--- throttle body angle sensor
--- MAP sensor (measuring pressure)
--- air temp sensor
--- welding wiring
--- standalone

One of the most difficult part is to calculate the right dimensions of the throttle body function of various parameters. It's not just 4 aluminium tubes and let's go.
Even if the 1ZZ-FE make power until 6800 rpms after tuned Standalone, the engine is mainly made for mid range and not high revs.

Great info here, I genuinely appreciate it. I was looking around and found this piece of kit in South Africa.

I figured I could cut out some of the ITB specific needs with a closed intake. Kind of defeats the purpose, but what kind of air would I be sucking in next to the firewall behind the engine anyways lol. Once again, 2zz would be easier and more cost effective, but the 1zz is a fresh swap and I consider myself a novice driver. I value getting tons of seat time and then making more power when I know how to actually utilize it.

 

[Funnyman]

To me, the right benefice of having ITB is to have equal air flow into each cylinder. A small airbox limits the gains of an ITB. Cylinders 4 and 2 will sucking fresh air, then the 2nd and 1st cylinders will getting less air. Next to ITB, air flowing is the main key. The setup with airbox for sale is cheap and not gonna help you because incomplete (just 4 rectangles holes). There are no individuals trumpets. You will ended with complex/non reliable thing for the stock configuration (unique throttle body).

With ITB's setup, a big airbox is designed to stock fresh air. ITB airbox's will be linked to big tube hose (~90mm) linked into engine bay into side vent. This is how is made the 2ZZ MR-S ITB equiped of Asano of Techno Pro Spirit.

Here the right set up you should have at least :

 

[dblotii]

With ITB, the MAF become useless and you need :
--- individual throttle body
--- specific fuel rail
--- throttle body angle sensor
--- MAP sensor (measuring pressure)
--- air temp sensor
--- welding wiring
--- standalone

One of the most difficult part is to calculate the right dimensions of the throttle body function of various parameters. It's not just 4 aluminium tubes and let's go.
Even if the 1ZZ-FE make power until 6800 rpms after tuned Standalone, the engine is mainly made for mid range and not high revs.

You have it reversed: With individual throttle bodies, you can still use MAF, but you can't use MAP unless you measure pressure downstream of the throttle bodies, and that won't work very well because you will have very high pressure fluctuations at the individual cylinders and therefore a good average MAP signal will be very difficult to process. The 20 V 4age used MAF. The real advantage to individual throttle bodies is that you can run much more aggressive cam timings and still get a reasonable idle quality, because the nearly closed throttles at each inlet reduces the backflow during overlap. With cam phasing and other variable valve timing system (like VTEC) you can run pretty aggressive and long-duration cams without a lot of overlap, so almost no OEM uses ITB's any more.

Overall, this will be a total waste of time unless you are trying to make race-cams more streetable.

Dave

 

[dblotii]

To me, the right benefice of having ITB is to have equal air flow into each cylinder. A small airbox limits the gains of an ITB. Cylinders 4 and 2 will sucking fresh air, then the 2nd and 1st cylinders will getting less air. Next to ITB, air flowing is the main key. The setup with airbox for sale is cheap and not gonna help you because incomplete (just 4 rectangles holes). There are no individuals trumpets. You will ended with complex/non reliable thing for the stock configuration (unique throttle body).

With ITB's setup, a big airbox is designed to stock fresh air. ITB airbox's will be linked to big tube hose (~90mm) linked into engine bay into side vent. This is how is made the 2ZZ MR-S ITB equiped of Asano of Techno Pro Spirit.

Here the right set up you should have at least :

Part of the normal engine development process for any engine and any new intake manifold is getting nearly equal airflow to each cylinder. At full-power when the ITB's are all wide-open. the cylinder-cylinder airflow is still governed by how good a job they did developing the flow into and through the airbox. Overall, ITB's really don't improve air-distribution compared to a good modern intake manifold.

 

[MineCowMcGee]

To me, the right benefice of having ITB is to have equal air flow into each cylinder. A small airbox limits the gains of an ITB. Cylinders 4 and 2 will sucking fresh air, then the 2nd and 1st cylinders will getting less air. Next to ITB, air flowing is the main key. The setup with airbox for sale is cheap and not gonna help you because incomplete (just 4 rectangles holes). There are no individuals trumpets. You will ended with complex/non reliable thing for the stock configuration (unique throttle body).

With ITB's setup, a big airbox is designed to stock fresh air. ITB airbox's will be linked to big tube hose (~90mm) linked into engine bay into side vent. This is how is made the 2ZZ MR-S ITB equiped of Asano of Techno Pro Spirit.

Here the right set up you should have at least :

I've seen the TPS cars setup. That would be ideal, and from everything Ive gathered, aggressive cams would be a must to see any real benefit from the throttle bodies. Which also apparently means upgraded valve springs. But do you think if all of the supporting mods are there, it would be reasonably worth it? 2ZZ is more cost effective, but ya know.

 

[MineCowMcGee]

Part of the normal engine development process for any engine and any new intake manifold is getting nearly equal airflow to each cylinder. At full-power when the ITB's are all wide-open. the cylinder-cylinder airflow is still governed by how good a job they did developing the flow into and through the airbox. Overall, ITB's really don't improve air-distribution compared to a good modern intake manifold.

Would the stock manifold be considered "modern" and "good"? I know the 1zz manifold is extremely durable for high power, but this is also an economical motor.

 

[Funnyman]

Stock manifold is well made for the 1ZZ-FE. If you want the induction noise (similar to ITB), you can do like I did. It's loud on cold start and full throttle.

 

[MineCowMcGee]

Stock manifold is well made for the 1ZZ-FE. If you want the induction noise (similar to ITB), you can do like I did. It's loud on cold start and full throttle.

Wow, placing it right behind your head! I like it!

 

[FormInFunction]

Stock manifold is well made for the 1ZZ-FE. If you want the induction noise (similar to ITB), you can do like I did. It's loud on cold start and full throttle.

That length of piping is insane. Its reminds me of an offroader snorkel

Did you leave that gap in piping near the side vent or seal that off completely? It seems like the added resistance to flow from the increased length would cause issues at high rpms...any changes in IATs that you noticed? My car is more intake noise than exhaust as well (until lift kicks in I suppose). It definitely makes it addicting to rev out gears a bit higher during quick accelerations.

 

[dblotii]

Would the stock manifold be considered "modern" and "good"? I know the 1zz manifold is extremely durable for high power, but this is also an economical motor.

Yes the stock manifold was designed and developed with the aid of Computational Fluid Dynamics, CAD, and modern flow bench and engine dyno testing methods.

 

[Funnyman]

That length of piping is insane. Its reminds me of an offroader snorkel

Did you leave that gap in piping near the side vent or seal that off completely? It seems like the added resistance to flow from the increased length would cause issues at high rpms...any changes in IATs that you noticed? My car is more intake noise than exhaust as well (until lift kicks in I suppose). It definitely makes it addicting to rev out gears a bit higher during quick accelerations.

Yes, I leaved the gap. The engine suck air from the side vent. The inside hose is just there for transfering the induction noise. The 60mm hose give instantaneous power/torque, something that a dyno doesn't show. In dynamic, the engine is responsive even with a little bit of throttle, especially on uper road and SP98 consumption become really economical. No more lag like an open CAI. After a dyno session, the 60mm hose is limiting air into the throttle body after 6100 rpms and power/torque curves are falling. Before that rpm, power torque curve are almost the same (dvantage for the 60mm in some rpms). The right diameter is 75mm. 83mm is too big and do not fit the hole of the side vent.

I tried plastic hose but the induction noise was a little fake/plastic. Aluminium hose is transfering the right/authentic induction noise with a tinny bit of reverb. On full throttle, it sound like Asano's MR-S 2ZZ with ITB, the 8500rpms in less. Here before the installation of the hose that goes inside the car :

 

[FormInFunction]

Makes much more sense that the extension to the cabin is for sound & mot one continuous tube. When you said those pics of it were still incomplete I thought you snorkeled it all the way to the interior as one pipe!

 

[MR2-D2]

Sick, you’re also in the rabbit hole of ITBs. Which 20v ITBs do you have? Black top and silver tops are different.

I also was going to try and do it while keeping the car as close to stock as possible but it was a pipe dream. Don’t use a maf, it’s pointless. The MAP issue can be improved if the downstream vacuum source from each runner is first routed to a vacuum block. Idk what the ae101 silver tops use but blacktops are MAP.

not exactly 1zz but I’m 2zz itb turboing mine and designed a manifold that I’m currently getting cast. I wanted to get it done and be the first one but I’m having material cracking issues and TPS beat me to it lol

I also designed one for 1zz but since I don’t have that engine anymore I haven’t printed the 1zz intake flange to check my measurements yet.

An air box also is really the only way to do it. Since I’m close to finishing it, I bought the Manon racing plenum. Don’t exactly need trumpets there since each runner exit on it has a gradual radius into the entry.

the problems you’ll run in to with that South African one (and I’m basing this on my experience with setting up my manifold on a 2zz) is the alternator getting in the way of the plenum and the fact that it’s a small spacer limiting your options on runner length.

ITBs introduce another aspect of tuning with runner length. Longer runners mean “more mid range torque, less top end power” and shorter means “less torque mid range, more top end power”. Based on that, that spacer and plenum would mean you’d have less torque than stock and just top end power. How much? Well I cant tell you that but the general consensus on ITBS is “noticeable” and “not much” respectively. There’s a guy on YouTube who messes with a truck he put ITBs on where he posts dyno figures on different runner lengths.

Considering the 1zz doesn’t Rev that high, that spacer thing is not a great option unless you have venturi Stacks that space the plenum from the throttles. Not to mention you’d still need either trumpets, for smooth airflow, or that manon plenum I bought. (Unless of course that plenum is like mine, I’m which case all you need are spacers/venturis)

I love talking about my project so if you need ideas I’ll post pictures lol

 

[MineCowMcGee]

Sick, you’re also in the rabbit hole of ITBs. Which 20v ITBs do you have? Black top and silver tops are different.

I also was going to try and do it while keeping the car as close to stock as possible but it was a pipe dream. Don’t use a maf, it’s pointless. The MAP issue can be improved if the downstream vacuum source from each runner is first routed to a vacuum block. Idk what the ae101 silver tops use but blacktops are MAP.

not exactly 1zz but I’m 2zz itb turboing mine and designed a manifold that I’m currently getting cast. I wanted to get it done and be the first one but I’m having material cracking issues and TPS beat me to it lol

I also designed one for 1zz but since I don’t have that engine anymore I haven’t printed the 1zz intake flange to check my measurements yet.

An air box also is really the only way to do it. Since I’m close to finishing it, I bought the Manon racing plenum. Don’t exactly need trumpets there since each runner exit on it has a gradual radius into the entry.

the problems you’ll run in to with that South African one (and I’m basing this on my experience with setting up my manifold on a 2zz) is the alternator getting in the way of the plenum and the fact that it’s a small spacer limiting your options on runner length.

ITBs introduce another aspect of tuning with runner length. Longer runners mean “more mid range torque, less top end power” and shorter means “less torque mid range, more top end power”. Based on that, that spacer and plenum would mean you’d have less torque than stock and just top end power. How much? Well I cant tell you that but the general consensus on ITBS is “noticeable” and “not much” respectively. There’s a guy on YouTube who messes with a truck he put ITBs on where he posts dyno figures on different runner lengths.

Considering the 1zz doesn’t Rev that high, that spacer thing is not a great option unless you have venturi Stacks that space the plenum from the throttles. Not to mention you’d still need either trumpets, for smooth airflow, or that manon plenum I bought. (Unless of course that plenum is like mine, I’m which case all you need are spacers/venturis)

I love talking about my project so if you need ideas I’ll post pictures lol

Wow, that is a fantastic write up! I have silvertop ITB's, which by default are MAF I believe. The silvertops used an air box from the factory. Good to know about the alternator clearance. Figuring out the "optimal" setup for runner length and trumpets would be nice, but I think I will be limited by firewall clearance, even if I cut it up. Just about everyone on facebook has told me I'm wasting my time unless I also throw some aggressive cams in as well, do you have any input on that? I would love to see more pictures of your project, including a list of things you've needed to make the ITBs work as well. Thank you for sharing your knowledge and experience!

 

[JohnzyMR2]

Yes, I leaved the gap. The engine suck air from the side vent. The inside hose is just there for transfering the induction noise. The 60mm hose give instantaneous power/torque, something that a dyno doesn't show. In dynamic, the engine is responsive even with a little bit of throttle, especially on uper road and SP98 consumption become really economical. No more lag like an open CAI. After a dyno session, the 60mm hose is limiting air into the throttle body after 6100 rpms and power/torque curves are falling. Before that rpm, power torque curve are almost the same (dvantage for the 60mm in some rpms). The right diameter is 75mm. 83mm is too big and do not fit the hole of the side vent.

I tried plastic hose but the induction noise was a little fake/plastic. Aluminium hose is transfering the right/authentic induction noise with a tinny bit of reverb. On full throttle, it sound like Asano's MR-S 2ZZ with ITB, the 8500rpms in less. Here before the installation of the hose that goes inside the car :

you gave me an idea to make a cool3D printed vent. Make vent into a ram for the intake

 

[MR2-D2]

Wow, that is a fantastic write up! I have silvertop ITB's, which by default are MAF I believe. The silvertops used an air box from the factory. Good to know about the alternator clearance. Figuring out the "optimal" setup for runner length and trumpets would be nice, but I think I will be limited by firewall clearance, even if I cut it up. Just about everyone on facebook has told me I'm wasting my time unless I also throw some aggressive cams in as well, do you have any input on that? I would love to see more pictures of your project, including a list of things you've needed to make the ITBs work as well. Thank you for sharing your knowledge and experience!

oh yeah, the rears on those are round I think? If you send me pictures and calipers measurements I can make a flange that works with my manifold..... Blacktops also have a plenum!

As for the optimal, I designed my manifold so that I can change runner length depending on my goals. Plus, since it's lost wax casting, I can assemble the whole thing in wax first and then cast so there are minimal sharp points; great for flow!

I also got a lot of flack for it and would hear from other MR2 friends that people would shit on me but it apparently got really quiet once I neared the end haha. So just tune the naysayers out, if it's what you want and you're willing to do it, then go for it. But speaking to the firewall clearance, yeah you're pretty much forced to cut. If you want the cubbies and a roll bar like me, you're limited even more. I estimated my manifold to put the plenum where the soft top used to be so it should all fit (won't know until I have the manifold done). The fab guy just has to get creative. Eh cams aren't a necessity but the duration and lift of aggressive ones help with top end. I'm boosted so I don't personally care for it, and it'll make tuning idle much much harder (not to mention the worse fuel economy), but maybe in the future.

Well pretty much a manifold adapter, plenum and vacuum block is all you need to fit it on the engine. You will need to get a external vacuum solenoid that routes to the same vacuum block downstream of the throttles (unless you plan to retrofit ethrottle like I am). Everything else after that is just tailored specifically to how your routing is going to work.

There's a lot of pictures but you can look at my instagram shameless plug efthepizzaboy. I have them all on there. I'm just too lazy to go scrolling through my phone for pictures

 

[MineCowMcGee]

oh yeah, the rears on those are round I think? If you send me pictures and calipers measurements I can make a flange that works with my manifold..... Blacktops also have a plenum!

As for the optimal, I designed my manifold so that I can change runner length depending on my goals. Plus, since it's lost wax casting, I can assemble the whole thing in wax first and then cast so there are minimal sharp points; great for flow!

I also got a lot of flack for it and would hear from other MR2 friends that people would shit on me but it apparently got really quiet once I neared the end haha. So just tune the naysayers out, if it's what you want and you're willing to do it, then go for it. But speaking to the firewall clearance, yeah you're pretty much forced to cut. If you want the cubbies and a roll bar like me, you're limited even more. I estimated my manifold to put the plenum where the soft top used to be so it should all fit (won't know until I have the manifold done). The fab guy just has to get creative. Eh cams aren't a necessity but the duration and lift of aggressive ones help with top end. I'm boosted so I don't personally care for it, and it'll make tuning idle much much harder (not to mention the worse fuel economy), but maybe in the future.

Well pretty much a manifold adapter, plenum and vacuum block is all you need to fit it on the engine. You will need to get a external vacuum solenoid that routes to the same vacuum block downstream of the throttles (unless you plan to retrofit ethrottle like I am). Everything else after that is just tailored specifically to how your routing is going to work.

There's a lot of pictures but you can look at my instagram shameless plug efthepizzaboy. I have them all on there. I'm just too lazy to go scrolling through my phone for pictures

Hell yeah. Great info. I was going to have the boys at Panic help me out as well. Great to know that they already have experience with the subject. I'll be referring to this info a lot!

 

[MR2-D2]

Please do send me those dimensions though..... lol

Damn, yeah it seems like it got more popular. Back when I first started, nobody had anything. Let me know what info they give you! Might help me out too