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914World.com _ 914World Garage _ Single weber fix?
Posted by: CatDaddy60 Feb 4 2013, 09:45 AM
Ok I get it the fuel doesn't stay atomized in the runners and this causes poor fuel mileage, drivabillity concerns etc, I understand. But for those of us poor souls who for one reason or another are committed to this carb (the holley weber), has anyone tried heating the runners either electronically or with a subsequent exhaust runner ie type 1 vw and if so did it help with any of the concerns. my second question could anyone post a photo of what the throttle linkage should look like. i have a stock throttle cable and a cobbed together carb from a type 4 kit that has the carb turned 90 degrees and the cable wont reach the carb. any help will be appreciated.
Posted by: McMark Feb 4 2013, 10:45 AM
Use the aluminum or paper gaskets between the heads and the intake runners to transmit as much heat as possible. If you use the plastic 'phenolic' spacers your intake runners will stay cooler.
Otherwise, just do your best to tune it until you can get something better.
Posted by: '73-914kid Feb 4 2013, 11:11 AM
I know of a guy who is creating a single weber IDF setup for the type 4 that pumps oil around the intake runners to keep them hot. The intake helps to act as an oil cooler, prevent percolation of fuel, and then injects the oil back into the rocker boxes.
This is whaat he claims at least.. I'm yet to see it in action.
Posted by: monkeyboy Feb 4 2013, 12:00 PM
Just understand that there is more than one reason why that setup isn't the best...
If you heat the manifold you can get it to run better, but you will still have issues with that sharp turn that the manifolds take at the heads.
I know you say you are stuck with it, but it's just not the right design for this motor.
Posted by: Mikey914 Feb 4 2013, 12:05 PM
Have you though of going to dual webber set up?
The distance traveled to the head is shorter so it should allow the suspended fuel less time to become "un-atomized". Also closer to a straight shot into the head.
Posted by: LotusJoe Feb 4 2013, 02:19 PM
I started with the Weber 38/38 synchronous with the stock runners that come with the kit. I have since had runners made at FAT performance that are 54% larger. I then added the intake top and re-tuned the engine on the dyno. Now getting around 121 hp and seeing 13.8 Air/Fuel ratio. I think the 38/38 is a better carb than the 32/36 progessive that was used in years past. 
Posted by: saigon71 Feb 4 2013, 04:21 PM
I started with the Weber 38/38 synchronous with the stock runners that come with the kit. I have since had runners made at FAT performance that are 54% larger. I then added the intake top and re-tuned the engine on the dyno. Now getting around 121 hp and seeing 13.8 Air/Fuel ratio. I think the 38/38 is a better carb than the 32/36 progessive that was used in years past.
Joe:
What are the specs on your engine to be able to pull 121 HP with the single 38/38?
Thanks.
Posted by: LotusJoe Feb 4 2013, 05:54 PM
2056 using a 272 cam with 428 lift - 48mm / 38mm Valves with polished exhaust ports. Triad Performance exhaust
This carburetor is coming off in the spring and I'm switching to IDF type throttle bodies. Right now I'm leaning towards a kit from CB Performance. 
Posted by: struckn Feb 4 2013, 06:45 PM
could anyone post a photo of what the throttle linkage should look like. i have a stock throttle cable and a cobbed together carb from a type 4 kit that has the carb turned 90 degrees and the cable wont reach the carb. any help will be appreciated.
Posted by: CatDaddy60 Feb 4 2013, 07:31 PM
Thank you for the photos, as they say a picture is worth a thousand words.
Posted by: LotusJoe Feb 4 2013, 07:35 PM
Thank you for the photos, as they say a picture is worth a thousand words.
Is your carb a 32/36 progressive?
Posted by: CatDaddy60 Feb 5 2013, 09:41 AM
The carb have is a DGV32/36 5A with a manual choke. I'm in AZ so the choke isn't that big of a deal.
Attached thumbnail(s)
Posted by: CatDaddy60 Feb 5 2013, 09:44 AM
and the car it is going in
Attached thumbnail(s)
Posted by: Kirmizi Feb 5 2013, 10:24 AM
Give DJ at Don Jackson Enterprises a call (602.997.2785).
He's got a single carb on his daily driver 914, he might have some good suggestions.
Mike
Posted by: LotusJoe Feb 5 2013, 11:12 AM
The carb have is a DGV32/36 5A with a manual choke. I'm in AZ so the choke isn't that big of a deal.
The 38/38 has the linkage on the opposite side from the 32/36.
Posted by: CatDaddy60 Aug 30 2014, 12:39 PM
Give DJ at Don Jackson Enterprises a call (602.997.2785).
He's got a single carb on his daily driver 914, he might have some good suggestions.
Mike
Gave him a call and a visit and after some moves and a job change I'm working on the car again. Thank you for your assistance.
Posted by: mrholland2 Aug 30 2014, 04:55 PM
Fiat air cleaner with a gm snorkel that has a heat riser flap and rise the heat from the exhaust
Posted by: 02loftsmoor Aug 30 2014, 06:44 PM
could anyone post a photo of what the throttle linkage should look like. i have a stock throttle cable and a cobbed together carb from a type 4 kit that has the carb turned 90 degrees and the cable wont reach the carb. any help will be appreciated.
it works and it don't look bad
Posted by: Jake Raby Sep 1 2014, 01:41 PM
The runners are too long and the carb is too far away from the heat of the cylinder heads to keep the fuel from falling from suspension.
My experience with trying to make these rigs work better is about like putting lipstick on a pig.
Posted by: colingreene Sep 1 2014, 10:29 PM
why would anyone not want 2 carbs?
Posted by: Larmo63 Sep 1 2014, 10:30 PM
Posted by: 9146986 Sep 2 2014, 07:07 AM
The problem with the single progressive on a 914, is that someone made a kit, it bolts up, and it's cheap; so somehow it's gotta work right?
The single progressive will always fail to perform in one way or another. The only way those things do OK, is at cruising speed with a constant CFM.
You can tinker with the jetting, and if you find the intake manifolds with smallest runners you can find, it will help. Nothing will ever make it work right, or give you close to optimum performance.
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