# 38-DGES - - Good Choice for Autocross Racing?



## ON3WHLS (Jul 11, 2009)

Hi All:

New to carbs here and have a good opportunity to purchase a Redline 38 DGES kit. 

Is this a good application for an autocross race car where corner exit torque is most important (2,000-4,000 rpm window)?

It seems the kit would be good due to 1) the runner length of the manifold (better for mid range torque) and 2) the fact that the air is drawn in not directly above the exhaust manifold on a counterflow head, as is the case with DCOEs

Anyone with this setup? Even if you do not race your car, please feel free to chime in. Optimum jetting? My engine outputs probably 130-140 bhp, open exhaust, mild head work, mild aggressive cam.

Thanks :thumbup:


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## ON3WHLS (Jul 11, 2009)

OK I think I'm going to have a go at it. 

My goal is to have the car done for next season, so this project will pick up in the spring, but I'll be doing some odds and ends over the winter and plan on installing the carb. I'll use this as a project thread for those that might be interested in this setup. I've done a lot of research on carbs the last couple days on here and haven't found a whole lot on the 38/38 DGESs on the counterflow heads. From what I know, it seems to be a great match for me at this time.

As an intro, here is what I'm working with. It is a 1.8 8v Digifant II w/stock bottom end w/a match ported head w/270 deg cam, high rev valve springs, 3 angle valve cut. About 10.5 compression. Nothing crazy, it was an FSP car previously.










Here is the car:










E-Prepared Solo II Jetta 2-door currently about 1900# curb weight (still need to remove glass)

I should be ordering the carb kit this week. As for ignition, I have an old electromotive TECII, which I will be trading in for the XDI-2 fully programmable CD ignition.

My goal when all is said and done is somewhere in the range of 140-150 brake horsepower, which is plenty to make this car a screamer at its curb weight. :thumbup:


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## ON3WHLS (Jul 11, 2009)

Here is the Weber 38/38 DGES Sync from Redline, should be here on Wednesday!
First step, figure out the current jetting specs.


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## ON3WHLS (Jul 11, 2009)

Last night I checked the baseline settings on the jets and started to learn the adjustment on the floats. Everything was factory, except for the float settings and mains which ended up being 1.42 mm instead of 1.45 mm. These are pictured below, the two screws at the bottom of the fuel bowl. 

The kit I acquired was designed by Redline Weber for a 1.6L MKI Scirocco, so I may have to go a little bigger on the main jets, we'll see if it runs too lean.

I am still looking for some good info on how to adjust the floats. It is really surprising to me the instructions from Redline don't include this information, which is a critical setting on a carb :screwy: So far I've been searching and reading different forums, but think I'll get a Weber manual to aid in setting this thing up.


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## prbanos (Aug 31, 2008)

I love the fact that even though she's a track whore she still looks super clean:thumbup: 
Looking to see how it turns out because I'm looking to carb my mk2. good luck


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## ON3WHLS (Jul 11, 2009)

prbanos said:


> I love the fact that even though she's a track whore she still looks super clean:thumbup:
> Looking to see how it turns out because I'm looking to carb my mk2. good luck


 Haha, thanks. I'm in the middle of a couple other projects, one of which was to restore the bay and clean things up real good :thumbup: 

Here is some (I think, anyway LOL) cool stuff......... 

I finally found the recommended float settings on this site (bottom of page): 

http://www.racetep.com/weberX.html#jets 

Also found this tool for checking the float height, although I have a mini mill and can machine this fairly easily...but is it worth the time for $10? 

http://www.pegasusautoracing.com/productdetails.asp?RecID=5846 

Pegasus also make a ram horn inlet for the 32/36 carb, which will fit the 38! Too bad it is so expensive: 

http://www.pegasusautoracing.com/productdetails.asp?RecID=1254 

So far I've only found ITG race filters from the UK: 

http://www.fastroadcars.co.uk/shop/index.php?act=viewProd&productId=18 

I hope Santa comes this year! :biggrinsanta:


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## candm (Apr 27, 2003)

there is a place in california called coast fabrication that is an itg dealer. i purchased 2, dome style setups over the years for my dual carb rabbit and they wre a good company to deal with


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## B4S (Apr 16, 2003)

That downdraft velocity stack setup is pretty cool, probably adds a nice little growl to that carb. That's the one thing I missed while running a 32/36 for a while. There is a significant amount of machining required to run it though, it seems. It looks like you've got to cut the top cover flush with the filter mounting face. Not a huge deal, for what I figure is a nice improvement in function.


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## ON3WHLS (Jul 11, 2009)

It broke 15 degrees here in Michigan, so I got the manifold/carb installed. I need to remount the carb 180 degrees so the fuel inlet is on the passenger side and throttle linkage on the driver side, shouldn't be that big of a deal. It would have helped if I had installed the intake manifold/carb before the header, it made the job a little more difficult than it should have been having the header already installed on the head. Live and learn.

After I remount the carb, next is figuring out the fuel system. My plan is to run off the in tank MKII OE transfer pump and take out the main pump. I might leave it mounted and just bypass it, in case I ever want to return to using it again.

One thing I'm sort of clueless about here is whether or not the return line gets used? Does that connect up to the fuel pressure regulator, if it does get used?


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## ON3WHLS (Jul 11, 2009)

Some more info for those new to this setup. The second picture in the post above shows two ports in the intake manifold. The threaded port is used as a vacuum source, to the brake booster. The non threaded port (nipple) is actually a water fitting and there is a sister port on the opposite side. This is for connecting in the cooling system to warm up the manifold faster. I'm not using the water ports, since it is a race car. For the vacuum port, I am hoping this will not cause too much cyl to cyl variation in AFR. I've seen setups where people branch vacuum lines together from all four intake runners. If it is cause for concern, I may decide to remove the header and install lambda bosses on each individual exhaust runner, to capture each cylinders AFR. Still deciding if this is necessary at this point.


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## ON3WHLS (Jul 11, 2009)

Just finished up having the 58 tooth trigger wheel and aluminum v pulley I designed for the vw 8v engine machined, so am about to start wiring up the ignition controller and plumbing the fuel system for the carb this summer/fall. I'm sort of considering making these available for sale on the forums if there is any interest, there isn't much available off the shelf, so I could see a need.

I actually went a slightly different route for the ignition and purchased the new TEC-s. This will allow full mapable ignition control, with the option to change to fuel injection if the carb setup doesn't work out or I decide to switch in the future (I'm just not using the fuel injection portion of the SEM for now)


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## B4S (Apr 16, 2003)

Ooh, I like that a lot :thumbup:.


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## ON3WHLS (Jul 11, 2009)

B4S said:


> Ooh, I like that a lot :thumbup:.


Thanks. The wheel actually runs on the inside of the pulley, so it's a little bit different design that conceals the t wheel and sensor a bit more. The shop that machined it did a great job. Next up is the mag sensor bracket.


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## zcxerxes (Nov 13, 2005)

I run a 38/38 in my notchback on an aba/jh with a 288 web cam and my roommate has a 32/36 in his caddy with the same motor and a g-grind. Mine doesn't pick up rpm nearly as fast as his does down low but is much happier about 4500 than his is. Other than the carb and cam the motors are identical though. I know the cam plays a bit in that. Mines apart right now due to a sheared off woodruff on the crank gear but when it goes back together there have been a few conversations of hitting up the local dyno and swapping Carbs after a few pulls just to see what kind of a difference it makes. Also neither of us are running the vacuum advance on our distributors. I am only using the mechanical advance and had it set to 32* all in, not sure where his is set. I had an issue with the vacuum retarding timing then rpm dropping then it would retard more so on and so on till it would stall out. I like the dges but its a real pain adjusting the front idle or changing the front jet and make sure to get some heat wrap for your fuel line coming up by your header. I think if I were gonna autocross my car I would want the air velocity of the 32/36 over the volume of the 38/38. Imo
I probably just rambled off a bunch of really useless information.


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## ON3WHLS (Jul 11, 2009)

zcxerxes said:


> I run a 38/38 in my notchback on an aba/jh with a 288 web cam and my roommate has a 32/36 in his caddy with the same motor and a g-grind. Mine doesn't pick up rpm nearly as fast as his does down low but is much happier about 4500 than his is. Other than the carb and cam the motors are identical though. I know the cam plays a bit in that. Mines apart right now due to a sheared off woodruff on the crank gear but when it goes back together there have been a few conversations of hitting up the local dyno and swapping Carbs after a few pulls just to see what kind of a difference it makes. Also neither of us are running the vacuum advance on our distributors. I am only using the mechanical advance and had it set to 32* all in, not sure where his is set. I had an issue with the vacuum retarding timing then rpm dropping then it would retard more so on and so on till it would stall out. I like the dges but its a real pain adjusting the front idle or changing the front jet and make sure to get some heat wrap for your fuel line coming up by your header. I think if I were gonna autocross my car I would want the air velocity of the 32/36 over the volume of the 38/38. Imo
> I probably just rambled off a bunch of really useless information.


No not useless at all. Thanks for the input. Did you have a hard time adjusting the float level so you didn't get starvation during hard cornering? I run in 2nd gear the vast majority of the time, so revs are kept up; we'll see how it goes. And like you said, cam choice has a lot to do with it. I'm not running a super high RPM cam, it just doesn't make sense for autocrossing. If you could post pics of the throttle attachment at the carb, I would like to see that, too.

I've made little progress wrt the carb. I've been working on completing the brake system. I did pick up the ITG setup from Coast Fab. I'll post some updated pics soon. :thumbup:


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## zcxerxes (Nov 13, 2005)

Here's my setup in the car. Because of my the nature of it my throttle cable system is way different than yours is gonna be. Aircooled Throttle come straight back I made a couple brackets that held an oddessey no kink teflon lined brake cable for a bicycle. Lots of people say brake cables break but I can tell you I pull my brake cable on my bike way harder than my throttle will ever get stretched.
[video]http://static.photobucket.com/player.swf?file=http://vid61.photobucket.com/albums/h57/zcxerxes/notchback/2010-09-27_14-05-15_26.mp4[/video]
I set the float as per the instructions in the weber tuning manual and never had an issue with it again. I I think I would be more likely to have the starvation issue under hard throttle but had none. Only issues I had were the vacuum advance retarding timing (solved by removing vacuum advance and adding more timing) and the fuel boiling in the line feeding the carbon (solved by ordering some ceramic line sheathing from mcmastercarr) 

The dges is actually very user friendly compared to other Carbs I have delt with in the past.


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