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Wed Sep 05, 2007 8:20 pm

I'm sure this has been talked to death in here, but has anyone slapped a TBI setup from a small 4cyl on a VW engine?

I've looked into some multi-port VW stuff and it seems like overkill/expensive for a non-performance vehicle. Seems like a simple TBI setup adapted to a stock manifold shouldn't be too much of a problem.

Ideas?

Wed Sep 05, 2007 11:28 pm

Turbo city out of California,years ago made a T.B.I.setup that used a G.M. unit.Don't know if they still do or not.Hope this helps!

Thu Sep 06, 2007 1:03 am

I would say that if you're going to go ahead and put EFI on a VW engine, there's really no reason I can think of to go one way or the other. I guess it just depends on what you're trying to achieve.

For example, some people like their engines to look stock, but want the benefits of EFI (e.g. stock resto/resto rod). If I fell into that category, I would modify a standard carburator to function as a throttle body by removing the venturi's, pulgging idle/main circuts, and mounting an injector in such a way that it could be hidden by the stock air cleaner. That's quite a bit of work, so what most people do is use a TB from a production vehicle, and adapt it to work on the car's existing manifold. I don't see any reason why not to do that to a VW engine, aside from the normal fuel dropout/vapor lock issues people sometimes have with carb'd engines.

OTOH, multipoint parts for VW engines are really cheap these days, and if you have any aspirations of going turbo one day, MPI is the way to go IMO. For example, I put together an entire MPI system using Megasquirt and various bits and peices from the junkyard and CB Performance for less than the cost of only a standalone ECU from another company (greddy, ect).

Thu Sep 06, 2007 1:29 am

I don't really care about the stock look. I was just looking for an alternative to the fussiness/inefficientcy of a carburated system.
A friend of mine suggested something along the lines of a Suzuki Samuri TBI system...it's relatively simple and the engine size is close. With a addition of a few sensors, it doesn't seem too far-fetched.

Again, I'm not looking for super performance...just reliability and effiicientcy.

Quote: multipoint parts for VW engines are really cheap these days

Really? I haven't seen a full-on kit advertised for less than a few thousand bucks. Compare that to a cheap junkyard retrofit...

Thu Sep 06, 2007 1:57 am

This sounds very interesting.
I'm just starting to collect parts for a EFI system based around a MegaSquirt ECU. I'm not near any junk yards so I've been searching the Internet and eBay. The closest thing I've seen are EFI Motorcycle TBs. These usually come as a set of four, but some are easy to break apart.

Bikes tend to have smaller engines than acvws and their TBs are meant for one on each individual cylinder, but they rev a whole lot higher (like 14,000RPM)! That's like 3x what you might expect for a simple VW. This means one bike TB may have the capacity to handle a stock 1600cc VW engine.

I'll be interested i nwhat you find.

Thu Sep 06, 2007 3:36 am

I would go with port injection, with TBI you still have the fuel puddling in the manifold like you do with a stock carb. Port injection will increase the performance, drivability and the fuel economy over a TBI setup. The Megasquirt ECU along with a TB from a 2 litre car on a plenum style manifold are a good starting point.

Thu Sep 06, 2007 10:01 am

So the megasquirt can control a TBI setup? I'll have to study the megasquirt more.

I realize that a multi-port setup would be better, but I really don't want to mess with the stock manifold...I don't suppose I'd be afraid of fabbing a new piece between the DP end castings, though.

What about timing? Doesn't the computer in most TBI or multi-port systems sense the timing and control the advance accordingly?

Thu Sep 06, 2007 11:23 am

go to the shoptalkforums.com, go to the fuel injection forum for your education. I have been looking into this for some time, the new megesquirt two is really impressive, can now control all your ignition needs now as well. One aproach would be to use an early vw cis throttle body which is a two barrel progressive t/b. These have the same footprint as a weber progressive, so use a weber progressive manifold and use cb performance dual port end castings with the fuel injector bungs welded in, not a engineered plenum setup but should work well for a small displacement engine, and minimal fabrication. I am considering doing this, but some have said the dual port end casting will be way to restrictive for a 2110 even if opened up. Another option is the full on dual idf style throttle bodies but then you are into some serious money.

Another option would be to convert your pict 34 to a throttle body by removing the venturi and adapting a tps to it and use the cb end castings.

then lock out your 009 and add a pertronix, you probably already have these.

return fuel line, new pump and regulator 150

buy a preassembled megasquirt/harness $350

cb efi endcastings fuel rail and injectors $250

plus of course your time and tinkering but would be in another universe as far as driveability and economy, and simplicity. someone needs to do it.

Thu Sep 06, 2007 11:47 am

Culito wrote: So the megasquirt can control a TBI setup?

Yes.

Culito wrote: I realize that a multi-port setup would be better, but I really don't want to mess with the stock manifold...I don't suppose I'd be afraid of fabbing a new piece between the DP end castings, though.

if you don't want to mess with the stock setup too much, you can always mount a TPS on the carb and use THESE for a simple multipoint setup. That's what I did.

Culito wrote: What about timing? Doesn't the computer in most TBI or multi-port systems sense the timing and control the advance accordingly?

Megasquirt can control a wide range of ignition systems, and is even capable of driving coil on plug setups directly from the ECU. I'm using Ford's EDIS system, for distributorless ignition. All that's required for EDIS is the crank trigger, a trigger disk mounted on the pulley, the coil pack, control module, and the associated wiring. I got everything for free from a junkyard... :lol:

Thu Sep 06, 2007 1:16 pm

buying every piece you could put a multiport setup together for around, 1200 or so. I wouldn't waste my time w/ tbi it's barely a step above the carb. cb sells stock end castings with injector bungs in them. I built my own centersection to work w/ a ford tb and made my own fuel rails on my first setup.

Thu Sep 06, 2007 2:18 pm

Quote: Megasquirt can control a wide range of ignition systems, and is even capable of driving coil on plug setups directly from the ECU. I'm using Ford's EDIS system, for distributorless ignition. All that's required for EDIS is the crank trigger, a trigger disk mounted on the pulley, the coil pack, control module, and the associated wiring. I got everything for free from a junkyard...

Well that's pretty awesome.
How did you do your trigger/disk setup?

I'd like to see some pics of tbi or home made multi port setups.

Thu Sep 06, 2007 8:00 pm

Culito wrote:
I'd like to see some pics of tbi or home made multi port setups.

Well, I suppose I could show off a little.... :lol:
Here goes.

Thu Sep 06, 2007 8:44 pm

I mounted the trigger wheel with 5 allen head machine screws, lockwashers, and locktite on the threads to make sure it doesn't come apart at speed. It was a bitch to get it centered, it would have helped if I had bought a solid pulley instead of this one with the holes.

Or, you could just buy one from these guys:http://home.earthlink.net/~beanbooger/boost_engineering/

I haven't fabbed the bracket for the VR sensor just yet...

EFI end castings. They will be plummed to a single TB, for simplicity.....

....which is in turn fed by CB's turbo buggy header, and one of 4 different turbochargers (I don't know which one will work best yet :twisted: ) Oh yeah, it will be intercooled as well. That's as much progress as I've made since getting off the boat, more to come soon, I hope. :roll:
I'm a lazy b*stard!

Fri Sep 07, 2007 9:35 am

Cool stuff.

I guess since I'm pretty low on cash, I'll have to stick with my crappy 34 pict 3 for now.

But I'll be planning the ultimate setup in the meantime.

(insert evil laugh here)