TB selection

Gtikyle · Post by **Gtikyle** » Tue Apr 08, 2008 10:42 am

I've been researching and compiling a list of components that i will be needing to construct my MS project. This will be going on a 1641cc Aircooled VW motor, which right now is mostly stock with about ~50Hp. I plan to upgrade this powerplant in the future with larger displacement, and a turbo.

However, for now, i'm trying to do this on a budget, with fuel economy in mind. My plan is Dual intake port mani's with 4 injectors, all sharing a common plenum, with a single TB. I've read a bit on the sizing of TB's, but does anyone have suggestions for size/application? I want to source most everything from junkyards, so an OEM TB would be ideal.

LeslieTroyer · Post by **LeslieTroyer** » Tue Apr 08, 2008 12:53 pm

you might look at a type 3 TB and intake runners, that's what I'll be using on a 2014 I'm building -- but then it is going into a type 3 and not a type 1 or 2....

If you search I think others are using Ford TB's, I've also seen a ducati (sp??) injector setup for ACVW.

Les

Gtikyle · Post by **Gtikyle** » Tue Apr 08, 2008 2:21 pm

In regards to the Ducati Tb's, i would like to stay away from the exotic parts. I don't imagine those being cheap, or easy to find, in Washington, USA.
Ford TB's would be easy for me to pull from a junkyard. I suppose i could just wander around looking. Any size recomendations for such a low HP output motor?

devastator · Post by **devastator** » Thu Apr 10, 2008 6:41 am

I'm running a bigger ACVW engine and have a turbo but It sounds like you are looking to go that route right? With this in mind, I'll tell you that I'm using a TB off of a Dodge Neon. I believe it's 54mm, but I'm not sure. There were several Dodge vehicles that used the same TB, so finding one should be pretty easy.
Happy hunting.

Gtikyle · Post by **Gtikyle** » Thu Apr 10, 2008 7:00 am

Thanks for the tip. I will eventually go turbo/bigger displacement, but the idea at the moment is to just inject the 1641, and then when i have some cash, ill build a seperate block, maybe a 1914, or 2007 turbo.
Do you think 54mm is sized too big for a motor with < 60hp? I know when i upgrade to the bigger motor ill end up changing TB, and injectors anyways. So something cheap and simple for this motor is what im looking for.

LeslieTroyer · Post by **LeslieTroyer** » Thu Apr 10, 2008 7:15 am

devastator wrote: I believe it's 54mm, but I'm not sure.
Happy hunting.

any Idea how big one would need for a ~2000 cc NA ACVW ?? I'm beginning to wonder if the stock type 3 will flow enough air flow.

LEs

devastator · Post by **devastator** » Thu Apr 10, 2008 7:49 am

I run 28mm. venturi's in my 2180cc, dual carb'd, N/A engine and it runs great! I also used to run 32 mm. venturi's in my 1968cc, single carb'd, Turbocharged engine. No problem there either. I can calculate the CFM tonight on my laptop and get back to you, or you can use these numbers and estimate the TB size. This probably wasn't much help, so I'll try to get a better answer for you tonight.

AR 67202 · Post by **AR 67202** » Thu Apr 10, 2008 9:15 am

my 2.0 came stock with a 70mm TB... NA as well...

Gtikyle · Post by **Gtikyle** » Thu Apr 10, 2008 9:41 am

devastator wrote: I can calculate the CFM tonight on my laptop and get back to you, or you can use these numbers and estimate the TB size. This probably wasn't much help, so I'll try to get a better answer for you tonight.

I'd appreciate the help. Thanks!
Next step is sizing injectors, and finding a cheap source of those. Im thinking smaller honda or vw.

devastator · Post by **devastator** » Thu Apr 10, 2008 10:40 am

Just about anything that has an engine the same size, (roughly) as yours should work. You can always turn up the fuel pressure when you build bigger or even turbocharge, although this second option requires more work than just turning an adjustment screw. Just be sure you get injectors that fit in your runners. I'm using CB Performance intake runners and home-made fuel rails.. Which runners will you be using?

Gtikyle · Post by **Gtikyle** » Thu Apr 10, 2008 11:24 am

I plan on running those CB DP fuelinjection castings too. For fuel rails i was just going to buy stock extrusion, and machine out what i need (i have access to the university's machine shop). I was planning on a custom single runner/plenum, fed by a tb, that way i could just change the TB, and injectors (if needed) when it goes on the larger motor down the road.