44 idf carb jetting, What main jets should I be using? |
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44 idf carb jetting, What main jets should I be using? |
03blueboo |
Apr 3 2015, 12:15 AM
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#1
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Newbie Group: Members Posts: 31 Joined: 9-July 13 From: Lexington, KY Member No.: 16,108 Region Association: South East States |
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 |
stugray |
Apr 3 2015, 07:27 AM
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#2
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
What size are your venturis?
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stownsen914 |
Apr 3 2015, 08:08 AM
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#3
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Senior Member Group: Members Posts: 928 Joined: 3-October 06 From: Ossining, NY Member No.: 6,985 Region Association: None |
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 |
Kansas 914 |
Apr 3 2015, 09:57 AM
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#4
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Advanced Member Group: Members Posts: 2,999 Joined: 1-March 03 From: Durango, Colorado Member No.: 373 Region Association: Rocky Mountains |
Can we assume you are in Kentucky? What is the altitude there?
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gopack |
Apr 3 2015, 10:19 AM
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#5
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CHEESEHEAD in CA, MARK Group: Members Posts: 744 Joined: 7-August 04 From: Folsom, CA Member No.: 2,472 Region Association: Northern California |
GO BADGERS!
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colingreene |
Apr 4 2015, 12:36 AM
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#6
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Senior Member Group: Members Posts: 730 Joined: 17-October 13 From: Southern California Member No.: 16,526 Region Association: Southern California |
^ LUL
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03blueboo |
Apr 5 2015, 11:15 AM
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#7
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Newbie Group: Members Posts: 31 Joined: 9-July 13 From: Lexington, KY Member No.: 16,108 Region Association: South East States |
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. |
03blueboo |
Apr 5 2015, 11:17 AM
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#8
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Newbie Group: Members Posts: 31 Joined: 9-July 13 From: Lexington, KY Member No.: 16,108 Region Association: South East States |
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DBCooper |
Apr 5 2015, 12:21 PM
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#9
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14's in the 13's with ATTITUDE Group: Members Posts: 3,079 Joined: 25-August 04 From: Dazed and Confused Member No.: 2,618 Region Association: Northern California |
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Mike Bellis |
Apr 5 2015, 01:38 PM
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#10
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Resident Electrician Group: Members Posts: 8,346 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None |
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 |
Apr 5 2015, 03:39 PM
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#11
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Newbie Group: Members Posts: 31 Joined: 9-July 13 From: Lexington, KY Member No.: 16,108 Region Association: South East States |
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. |
Larmo63 |
Apr 5 2015, 03:57 PM
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#12
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Advanced Member Group: Members Posts: 4,267 Joined: 3-March 14 From: San Clemente, Ca Member No.: 17,068 Region Association: Southern California |
I am going to run 40 Webers with 28mm venturis on my 2056.
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colingreene |
Apr 5 2015, 10:48 PM
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#13
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Senior Member Group: Members Posts: 730 Joined: 17-October 13 From: Southern California Member No.: 16,526 Region Association: Southern California |
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 |
03blueboo |
Apr 6 2015, 11:29 AM
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#14
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Newbie Group: Members Posts: 31 Joined: 9-July 13 From: Lexington, KY Member No.: 16,108 Region Association: South East States |
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