VW Megasquirt Forum

[wigsauto]

Hello
So here is the plenum I made up to fit on a Zenith manifold I had laying around.

This is mainly a way to attach the TB I got from jrandy to an 1835 I had to get some testing with MS.

The plenum is about 2 liters in volume.

I have it in a 66 single cab now for testing and tuning. So far it works OK, but the throttle response is a little abrupt.

I think I am getting a larger throttle opening with a small pedal movement compared to the 40 IDF's the truck had before.

Some linkage changes may help with this later.

[jrandy]

I tried reducing the pic's file size.

[vdubjim]

looks cool.

Do you think the rabbit or audi TB would be better? it bolts onto the center section, but i guess would loose the 2 liter volume.

Have you thought about a cable to the TB setup instead of linkage?

[wigsauto]

Yeah, a cable might be good because then I could make the throttle progressive opening.

I kind of wanted to have some plenum volume just to see what it would do.
I had the ford part here on hand, but didnt have a vw or audi handy.
Aren't the rabbit TB's progressive? As in large and small butterfly where the small one opens first then the large one.
I think that would be a little strange bolted straight to the center section, but with a plenum in between, it might be just the ticket.

I thought the mustang TB would be too big, but so far I cant really see much ill effect from it.

[vdubjim]

looking at pics i wonder if the intake volume of the progressive is similar to the mexi FI intake.
the progressive is aluminum and can be bored out a bunch.

I was just trying to think of a simple and cheap bolt on dealy that looks ok without much welding.

[wigsauto]

Yeah, maybe if you used a center section from a weber progressive DGFV? or whatever they are and then put the rabbit TB on it.
I think the progressive weber center section has some open area below the butterfly that would act as plenum.
That might be a clean setup if the linkage can be worked out.

[vdubjim]

there are lots of those intakes on samba.com at like 20 bones.


Bore out that center splitter for more volume, throw this on:


rabbit vs audi. audi 5k is larger. Similar to early 90s 16v jetta/golf
there are tons that use this same bolt pattern, but have the linkage on one side or the other, different spring combos and lengths etc..
Most of the automatics had TPS factory.

To join the TB to an airfilter pipe etc..

or this might fit, and the bottom is already round.


Use a cable for the throttle, no linkage to mess with, you could 'adjust' the pedal by using diff length arms for the cable on the TB

[vdubjim]

get any more done on it?

[wigsauto]

Not much progress lately, just been driving it.
I had a problem losing tach signal to MS and Matt from DIY advised to put a zener diode inline with the tach wire.
That seems to have cured it.

Now I am starting to work on the EDIS.
I will have to get around to working on that linkage though, because it is tricky to drive.