T4 Carburation Alternatives (cross-posted in Type 4Rum)

[speeddiallvmc]

Situation: 76 Baywindow, 2.0l T4 engine, converted from FI to single DFEV by former owner.
Location: Laramie, WY, 7300'ASL

1) Is a pair of Weber 34 ICTs really my best/only option for this engine at this altitude, with reliability and mileage the biggest concerns?

2) Should it be possible to wrap the intake runners on a center-mount manifold with some sort of thermostat-controlled 12v heater <whatever> to deal with icing problems, in lieu of exhaust heat risers?

3) Any ideas of jetting for both the DFEV and the Weber 34ICT for 7300' ASL?

4) Pros/Cons re the EMPI 34 ICT knockoffs for a 2.0l application?

For the record, in a less-than-fully-informed state, I attempted to order a pair of Solex 34 carbs from a vendor who conscientiously and politely refused to fill the order, stating that those carbs simply didn't flow enough to match a 2.0l engine (thank you CBPerf for you honesty). The electric chokes would have been nice, though.

Thank you all.

[busman78]

To start pick another venfor and go with the Weber 34ICT if duals are the direction you are heading. A single 34ICT or ICH carb flows 150cfm, a stock 2.0L at best will be 65% efficient and require only 104cfm, at 75% efficient 120cfm, so if one will run your engine the odds of two are pretty much a given. I have a single barrel manifold for the T4 engine and have tested the above with a Weber 34ICH & ICT carb. Here is a link to the posting in the Samba, if you scroll down through the thread you will see how I brought warm air to the air cleaner, I am at 5K feet and had no icing this past winter. Also ran that warm air set up with the normal dual runner manifolds and no icing.
http://www.thesamba.com/vw/forum/viewto ... light=t127

I can look up the jetting I have used with dual 34ICT on a 2.0L at this altitude, correction would be a factor of two sizes for your altitude.

Here are the jet settings for the Weber DFEV on the 2.0L, engine has larger valves @39X33, CB Performance 2201 cam, compression 8.0:1
Idle 55/50
Main 145/150
AC 170/180
Pump 55
Emmulsion F6/F6

[speeddiallvmc]

TU Bussman. Good info, here and in your referenced thread.

I'll be ordering the Webers, and putting the DFEV stuff on ebay.

[busman78]

Cool, here is the dual ICT jetting when I had them installed.

Idle 57
Main 142
AC 170
Pump 50
Emul F5

[speeddiallvmc]

Thank you again.

To continue this topic, is there any reason why DFEVs have not been offered in a dual setup? I would think a pair of progressives could be a really cool deal.

[busman78]

Years ago CB Performance sold a dual Weber 24/24 progressive set up, I have had two of them, they are neat, performance wise a little better than a set of 34ICT's. Sets of the 24/24 show up for sale. It is interesting in that the base bolt pattern for the 24/24 was the same as the 32/36, but the manifold would need to be releived a little on the 36 bore position.

[barls]

id go 40mm dels personally.

[speeddiallvmc]

Not to seem ungrateful to all offers of advice, but I struck out ordering the Weber 34ICTs. They were out of stock at the vendor I attempted to order from (nothing to indicate this on their website). This would be strike 2...

...which I took as an omen suggesting I should research a little further. Having had experience with a set of Kadrons WAY back in the day (on a 1776 Type 1 engine), I poked around a bit. Lo and behold, I stumbled across a remanufactured/rebushed kit (with SVDA spinny-thing!) from Kaddie Shack, jetted to my displacement and altitude! Price was right, and I certainly have nothing against refurbed parts, given that is how I earn my livelihood (in another context, as a Maintenance Machinist).

Here's another question - how should any carb, jetted for 7300' ASL, perform at lower elevations (say, down to sea level)? We go up to Vedauwoo camping quite a bit (8200'ASL), and down (up?) to Estes Park (7522), so neither of these locales should pose any major problems, but we will also be wandering hither and yon, including a must-do trip to the ocean somewhere.

Vielen Dank

[wildthings]

As a general rule you need to jet your carb for the lowest altitude you will be driving at. Going down in elevation makes a carb run leaner which can cause the burn to occur slower leaving more waste heat to deal with.