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> 44 idf carb jetting, What main jets should I be using?
03blueboo
post Apr 3 2015, 12:15 AM
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I recently upgraded to the 2056 engine. I opted to use Empi 44s which I believe have 135 main jets. The problem I'm having is that in 3-5 gears, at about 4200 rpm, the engine just doesn't want to accelerate any more. I've been told to put bigger main jets in and that that should help.

I'm just wondering if anyone here has any input, and also what others are doing with the 2056.

Thanks

Nate
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stugray
post Apr 3 2015, 07:27 AM
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What size are your venturis?
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stownsen914
post Apr 3 2015, 08:08 AM
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Lots of other factors to take into account as well - exhaust, cam, compression, any head work, (venturis as mentioned), etc. With that said, 135 seems in the ballpark. I ran a 2.0L years ago with Webers 44's, Euro pistons, a 3/4 race cam, mildly ported heads, and headers, and I used 145 mains. It ran well, and tuned with an EGT gauge, for what it's worth.

Scott
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Kansas 914
post Apr 3 2015, 09:57 AM
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Can we assume you are in Kentucky? What is the altitude there?
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gopack
post Apr 3 2015, 10:19 AM
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GO BADGERS!
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colingreene
post Apr 4 2015, 12:36 AM
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^ LUL
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03blueboo
post Apr 5 2015, 11:15 AM
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The altitude is right around 1000 feet. I'm not sure about the venturis. All I really know about the engine is that the cam is approximately "an Engle 120". That's what the engine builder said anyway. They're also the ones that recommended the 44s, but didn't give any I do for their set up.

On a side note, has anyone done a mechanical injection on a type IV? My guy here recommends some sort of injection over carbs.
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03blueboo
post Apr 5 2015, 11:17 AM
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QUOTE(gopack @ Apr 3 2015, 12:19 PM) *

GO BADGERS!



Yeah, that was fairly disappointing. I really wanted to see them play and beat Duke.

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DBCooper
post Apr 5 2015, 12:21 PM
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QUOTE(03blueboo @ Apr 5 2015, 10:17 AM) *

QUOTE(gopack @ Apr 3 2015, 12:19 PM) *

GO BADGERS!


Yeah, that was fairly disappointing. I really wanted to see them play and beat Duke.

"Go Badgers?" Then I'd say there's a good chance you'll get that wish.
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Mike Bellis
post Apr 5 2015, 01:38 PM
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I think 44's are a little big for that T4 combo. VW T1 guys run them all the time but the engines react different. Most T4 guys run smaller venturis when running 44's to keep the velocity higher. Smaller venturis make the most benefit at low rpm. If you are running out of fuel at higher rpm, it may be a combination of things. Jet size and fuel pressure along with fuel volume are some things to consider.
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03blueboo
post Apr 5 2015, 03:39 PM
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QUOTE(Mike Bellis @ Apr 5 2015, 03:38 PM) *

I think 44's are a little big for that T4 combo. VW T1 guys run them all the time but the engines react different. Most T4 guys run smaller venturis when running 44's to keep the velocity higher. Smaller venturis make the most benefit at low rpm. If you are running out of fuel at higher rpm, it may be a combination of things. Jet size and fuel pressure along with fuel volume are some things to consider.



Thanks. I'll start checking this week. Bad weather in KY so plenty of time to tinker.
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Larmo63
post Apr 5 2015, 03:57 PM
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I am going to run 40 Webers with 28mm venturis on my 2056.
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colingreene
post Apr 5 2015, 10:48 PM
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you need to know what size your venturi is to size the main jets correctly.
I have a set of 44s on my 2258 with a 34 vent. usually the main is 4x the vent size.
so
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03blueboo
post Apr 6 2015, 11:29 AM
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QUOTE(colingreene @ Apr 6 2015, 12:48 AM) *

you need to know what size your venturi is to size the main jets correctly.
I have a set of 44s on my 2258 with a 34 vent. usually the main is 4x the vent size.
so



Thanks!
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