tooter's manifold adventure...

[Bluevitz-rs]

http://www.yarisworld.com/forums/sho...=throttle+body
http://www.yarisworld.com/forums/sho...=throttle+body

there's been a few threads on it...

[CrankyOldMan]

There have been very mixed results with the 4-bolt DBW Corolla TBs, ranging from no issues to abject failure. They are electrically compatible, but the only real benefit from using one (w/o engine management) is that you effectively open the throttle faster. The corolla has a larger diameter TB, so you allow more air flow for the same throttle signal.

Beyond that, I really don't know the specifics. There's the potential to lean out your AFR too much at WOT because the ECU isn't expecting that much air to be available, and the stock fuel maps may cause it to misbehave.

Going to a 3-bolt, cable throttle with a separate throttle position sensor (TPS) is only practical with standalone engine management (this is how Garm gets away with it) due to unresolved issues with the stock TPS signal. I believe that CTScott poked around with a scope and meter on a stock TB but wasn't able (?) to make sense of the signals.

There has been a good deal of debate and experimenting with this, but no magic bullet solution. It mostly comes down to the stock ECU being a "learning" unit, and it's not happy with signals outside of the expected range.

[tooter]

Thanks for the threads, Blue.

I don't think I want to get involved in drilling out rivets, swapping chips, cracking idle screws, and rerouting coolant lines just now. Right now I'm focused on just one project... the manifold. Things turn out the best when I only do one thing at a time.

[cali yaris]

First, because it it is plenty strong to take being pressurized,

The stock manifold will handle 20+ psi of boost. It's pretty strong. Chris Rado ran his time attack tC the whole first season with a stock plastic mani on it. On the Yaris, I haven't heard of one failing, and we have quite a few turbo kits out there running various levels of boost.

[tooter]

Thanks for the info, Garm.

I know nothing about forced induction, and just figured that the stock plastic OEM manifold was designed for vacuum and not pressure.

[packetrace]

where did you bought the oem gasket ?

I will need to pickup a bunch of gasket :)

[tooter]

Test fitting time...



It's a drop in fit!

Did a little fine tuning with the Dremel. Since these were both undercuts, I just did them by hand...





Clears the fuel rail perfectly with ~almost~ zero clearance...



Ports matched flawlessly...



Next up: test fit the throttle body.

[tooter]

The flange is now a drop in fit, the throttle body bolts onto the adaptor like a dream, and the rest of the manifold has no clearance issues... ( goody )













However... nothing else fits!

All of the hoses are going to need rerouting, and I'm going to have to find a way to (gulp!) lose 2 3/4 inches on the already super short ram intake to make the air filter fit. But these issues are minor compared to getting the manifold itself to work out.

[vten]

Wow I like how the first pic look !

[Bluevitz-rs]

you should do a little cleanup of the head while the flange has no runners on it. would make it SUPER easy to 100% port match it and get rid of the casting marks.

[fnkngrv]

this work is SO much fun to watch. i applaud you.

[tooter]

Originally Posted by Bluevitz-rs

you should do a little cleanup of the head while the flange has no runners on it. would make it SUPER easy to 100% port match it and get rid of the casting marks.

If the head was off the engine I'd give it a whirl. But with the head on, I don't want to risk getting metal chips in the engine.

[tooter]

Originally Posted by fnkngrv

this work is SO much fun to watch. i applaud you.

Thanks, groove...

I'm having so much fun learning from this unfolding process and addressing the details as they present themselves by coming up with creative solutions.

[Bluevitz-rs]

Originally Posted by tooter

If the head was off the engine I'd give it a whirl. But with the head on, I don't want to risk getting metal chips in the engine.

There's no risk if the valves are closed. Then just blow it out with compressed air.

[packetrace]

how much for the flange and adaptor ? can you hve other one made ? :D

[tooter]

Originally Posted by Bluevitz-rs

There's no risk if the valves are closed. Then just blow it out with compressed air.

This is just a personal preference and I know that other people do this... but I'm not going to grind on a head when its on the engine. There is a sticky residue inside the engine ports that will make small chips stick in the crevices around the valve stems and valve heads even under pressurized air. there's also an issue of blowing tiny metal chips around under the hood. that means the alternator needs to be covered as well as the belt so that chips don't get stuck under it. With one cylinder's valves closed, some of the others will be open, so they would need to be plugged and taped. The only way I'd grind is if the valves were out and the head could be hot tanked afterwards.

There's also another reason... that would be making two changes at once, so I wouldn't be able to accurately quantify the difference on the dyno with just the manifold itself.

But, hey, you're perfectly free to grind your head if you want.

The manifold can be glass beaded because afterwards it can be hot tanked to insure that every particle of blasting medium is gone. Being a junkyard part, it's totally filthy and sticky inside and would need professional cleaning even if it wasn't blasted. It's hard to make out, but this was the original condition...



The runners are all as dirty as those ports, and all the way through, as well as the complete inside of the plenum. There is an intake port that extends into the middle of the plenum which makes it impossible to clean without being totally immersed.

[CrankyOldMan]

Originally Posted by tooter

Being a junkyard part, it's totally filthy and sticky inside and would need professional cleaning even if it wasn't blasted. It's hard to make out, but this was the original condition...

The runners are all as dirty as those ports, and all the way through, as well as the complete inside of the plenum. There is an intake port that extends into the middle of the plenum which makes it impossible to clean without being totally immersed.

Mine was that dirty on the outside too. I'm not sure if this applies to non-TDI manifolds, but this seems to be a pretty popular method:
http://youtu.be/oet4qWeZuYA

[tooter]

Originally Posted by packetrace

how much for the flange and adaptor ? can you hve other one made ? :D

First I need to know if this setup will even work decently. That will determine whether or not it would be worth your while. We'll all find out if it's "go" or just "show" after the prototype has been run on the dyno.

But IF this works (and, man, that's a really big IF )...

...I do think that the mounting flange, throttle body adaptor and its 3 mounting bolts, and all 3 gaskets would make a really neato "do-it-yourself" kit.

Then you could simply get your own junkyard manifold and finish it up any way you'd like.