Thinking of going single TB

[andy198712]

Its been a while since i touched the beetle, my setup is

GSXR ITB's on home made manifolds, attached using GSXR carb rubbers.

Works Good but there is the issue of a good map signal with ITBs

Now it works fine i should state that, i've had some great tunes on it, its been better of Alpha N id say over speed density in my experience but as this is a hobby for me and i like the tuning side of it, i want to a good SD tune and i enjoy fine tuning and all that jazz.

So the plan is, gut my spare ITB's and use them as injector holders, remove the butterflies and plug the holes ect, shave them to make them look nice, then have them all feed into a central plenum and go single TB and hopefully then have a nice varied MAP signal, but this also makes a turbo setup easier in the future!

its a T1 with 2110cc 86B cam and 9.3:1, Porsche 911 cooling so good space for a plenum!

Another bonus of the single throttle body is easy to plumb in an idle control valve ect.


Anyone think i'm going hugely back wards?
i need to read up on plenum sizes and all that stuff but it'll give me something to do as i'm off work at the minute after a shoulder operation and need to occupy my mind so i don't spend loads of money online on stuff i don't need


Cheers

Andy

[andy198712]

May as well add some more details now.

Just brought a DJ 2.1 plenum and TB off ebay which will be joined via 1.5in tubing to each port.... and i'm making up some injector bungs to mount my injectors at the best location and angle i can in a T1.

Watch this space it'll be slow but i'll get there!

[Clonebug]

Go hunt on Ebay for a mid 90's Volvo 940 turbo TB. It would be perfect for you.
Anything in the 45-57mm range would probably work great.

[andy198712]

was hoping the 50mm WBX one would work fine for me? (its included in the price)once i sort the TPS issue but i have a plan of one that may just fit that i already have....

[Clonebug]

That would work great as long as it isn't Drive by Wire.

[Dale M.]

TB off 2.4L Jeep has TPS, MAP and IAT....



Dale

[andy198712]

Thats pretty complete i'll keep that in mind, thanks Dale!

[andy198712]

so i measured the WBX TB and its 50mm, runner spigots on the plenum are a hair over 1.5inch which is ideal as thats what my runners will be, the plenum has nice cured entries to the runners which is nice too.

i need to get cracking on this and see if i can make the WBX TB work out easily, as it'll fit well ect... failing that dales suggestion looks good!

[andy198712]

well the TPS of an MG ZF throttle body i had looks like it can be made to work easily, just need to make up an adapter plate and i'm pretty good to go which is lucky!

held the plenum behind the porsche fan today and its tighter then i thought but looks workable!

[andy198712]

[andy198712]

been playing today, looks like having the throttle body pointing left is the best bet as there is more room over there and the throttle cable in that side, i'm going to flip the TB 180 degrees so the cable is pulling down.

to support the Plenum and TB it will be supported by the intake runners and i think i'll add a rubber mount to the back of the fan shroud...

making up the runners will be interesting, ive not got a great deal of experience with this sort of thing but i'll get there!