Possible VG30DE ITBs

[NolimitZ32]

I actually did a lot on paper, and in various CAD, then did some market research and concluded that there is absolutely no point in doing this because after all of the work it would have required I would have to have sold these setups for astronomical money to make the time spent worth my while. Then finding more than a couple people to pay such hefty sums for a mod that would net very little power on an engine that can use those dollars in other places more efficiently placed the final nail in the coffin of this little project. I may try to build a set for myself once I get a hold of another Z32 but I don't see it ever becoming something I ever produce or sell, even on a made to order basis.

[DCaff300ZX]

Very sad, but true to what I have also seen over the years researching this item. Basically the system would work best for an NA setup due to the need to have major fabrication to make an enclosed plenum for boosted VG's, as I saw with Rudy's build, and in the end as Anton suggests the results were not that great with still a lot of fiddling, engineering, and tuning to do to just then see a little gains probably less than any boost mods.
Space to mount the throttle setup is also an issue requiring a LOT of fab work and ingenuity, probably netting a final setup with high costs and minimal gains per dollar spent...basically something you do yourself if you can and want (based upon something other than best bang for the buck), and move on to other better modifications if not.
Too bad Escort didn't make more of their ITB setups, and support their product better back in the 90's!

[raremotive]

Granted you are not going to see much gains on paper. Or even dyno. However the gains are real in the sense that you are not filling an partially empty plenum before the runner gets air. With ITB's the plenum is full of ripe air ready for picking. Hence increasing throttle response.

This day in age we have tech that allows for variable valve lift. These babies render the ITB's gains pretty much useless, since the air now sits just above the valve before opening. For my RB26, I will be leaving the ITB's in due to being direct cam system.

I been formulating ideas on how to replace throttle-body for a system that can be used universally all engines, but you have to essentially sacrifice a head(or s for v-motors) to machine to allow fitment. The gains would be amazing. Tuning on the other hand is something I need to hash out since it changes how air comes in. Basically imagine an instant let of air.

[DCaff300ZX]

I wish I was inside your head, engineering tech is something I LOVE but know nearly nothing about beyond conversation and basic theory/practice. I went with my love of woodworking for my career, but have always stayed with my mechanical love at least by owning cool cars if not in building/engineering them. Surely it's why I do what I do with my Z...

I have always wondered why ITB and other more direct fuel/air inputs have not been the way engine tech has gone, so I LOVE hearing you say that...and hope like hell you make it happen. VVT and computer-aided engine management prove that there is a lot of room to work, just it seems to me that it has been a bit one-sided towards best for the computer and not what's best for an engine.
Glad that you and others still have this stuff banging around in your heads, and please keep us in the loop of conversation and such!