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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Thu Jan 12, 2012 4:27 pm Post subject: How much to step down on the mains? |
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I have a 1904 that I"m now dialing in. I believe I have things figured out with the exception of the mains.
They are Dell 40s and right now they have:
30mm vents
52 idles
180 airs
120 mains
9164.2 e-tubes
My AFR meter is reading pretty well with the exception of WOT. It dips down in the mid 11s and stays there at WOT.
Any suggestions on how far to drop the mains to get to the high 12s - low 13s at WOT?
Here's some of the engine info if needed...
1904 cc
Engle W110 with 1.25:1 rockers
stock type 3 heads P&P and HD single springs
Tri-Mil over the top exhaust
9.1:1 CR
Thanks in advance.
Last edited by mxracer on Thu Jan 12, 2012 4:31 pm; edited 1 time in total |
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baked beetle Samba Member
Joined: September 23, 2006 Posts: 1162 Location: Alberta, Canada
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Posted: Thu Jan 12, 2012 4:29 pm Post subject: |
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what are your emulsion tubes? _________________ These days people like me are hard to find- we don't give a damn what you think, about what we think. - JR
____________________
66' His
57' Theirs
63' Hers
62' Drag Bug - Theirs 13.1 @ 101 mph (GONE)
Last edited by baked beetle on Thu Jan 12, 2012 4:47 pm; edited 1 time in total |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Thu Jan 12, 2012 4:30 pm Post subject: |
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Oops..sorry...corrected above |
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baked beetle Samba Member
Joined: September 23, 2006 Posts: 1162 Location: Alberta, Canada
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Posted: Thu Jan 12, 2012 4:49 pm Post subject: |
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I would say one step would get you mid 12's which is good for WOT. but yea if you want to get the next step down 110, might be closer to 14.
this is a guessing game for anyone, if your the one with the wideband do you have extra jets or are you ordering _________________ These days people like me are hard to find- we don't give a damn what you think, about what we think. - JR
____________________
66' His
57' Theirs
63' Hers
62' Drag Bug - Theirs 13.1 @ 101 mph (GONE) |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Thu Jan 12, 2012 4:59 pm Post subject: |
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I'll be ordering again. I wanted to get some input on what to order before I did so I don't have more jets lying around. |
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Bill271 Samba Member
Joined: July 06, 2008 Posts: 761 Location: escondido
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Posted: Thu Jan 12, 2012 6:00 pm Post subject: |
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Try a 200 air |
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MURZI Samba Member
Joined: August 25, 2005 Posts: 5063 Location: Madisonville, La
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Posted: Thu Jan 12, 2012 6:24 pm Post subject: |
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What is AFR at a steady 3500 ? _________________ 62 vert
2276
Tim’s welded heads
45 Dells
A1 sidewinder
Fk44 cam |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Thu Jan 12, 2012 6:27 pm Post subject: |
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Right now it's 13.1-13.2 hoping the main drop will also move that a but and get me to the mid-high 13s
It's in a Type 3, so I'm not convinced I'm going to get the 16s that seems to be the goal with a Type 1. I'm pushing a little more weight. |
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MURZI Samba Member
Joined: August 25, 2005 Posts: 5063 Location: Madisonville, La
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Posted: Thu Jan 12, 2012 6:40 pm Post subject: |
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Try to reduce pump shot first. Also you may try a 6mm float level. _________________ 62 vert
2276
Tim’s welded heads
45 Dells
A1 sidewinder
Fk44 cam |
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Slow 1200 Samba Member
Joined: July 02, 2004 Posts: 2106
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Posted: Fri Jan 13, 2012 1:17 am Post subject: |
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in a type 3 you are probably running low profile air cleaners right? those probably are kind of restrictive as far as supplying air at WOT |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Fri Jan 13, 2012 6:20 am Post subject: |
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Pumps are backed all the way out at this point for tuning.
Changing float level will be last resort. In order to do that without 2 hours of "pain" I have to pull the engine.
Yes, they do have the short stacks and air cleaners on them. With a much bigger air (about a 2.50) I can get the main to the high 12s at WOT. The transition sucks at that point though. The restriction plays a part I'm sure. I am going to try a set of 2.00 airs today as suggested above too and see where that gets me.
I ordered a set of 115 mains to see how they work. In the end I'm testing and learning to it's all good.
Appreciate the suggestions and keep them coming. |
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MURZI Samba Member
Joined: August 25, 2005 Posts: 5063 Location: Madisonville, La
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Posted: Fri Jan 13, 2012 7:58 am Post subject: |
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You can progressively drill those airs bigger....much cheaper. _________________ 62 vert
2276
Tim’s welded heads
45 Dells
A1 sidewinder
Fk44 cam |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Fri Jan 13, 2012 8:03 am Post subject: |
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Yep, with you. The one set I have I've drilled up to 2.5mm. They are currently soldered back and at 1.85. Those are the ones I'll drill to a 200 and give it a shot.
Thanks |
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MURZI Samba Member
Joined: August 25, 2005 Posts: 5063 Location: Madisonville, La
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Posted: Fri Jan 13, 2012 8:29 am Post subject: |
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A slight bump in ignition timing, say two degrees, may help "clean up" that AFR slightly. Try it....... _________________ 62 vert
2276
Tim’s welded heads
45 Dells
A1 sidewinder
Fk44 cam |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Fri Jan 13, 2012 12:39 pm Post subject: |
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Bill271 wrote: |
Try a 200 air |
So the 200 air did the trick, thanks. At WOT I'm now at 12.8-13.1. Right where I wanted to be.
Cruise at 3500 bumped to 13.7-14.1. Not optimal from all the threads I've read here but I have yet to get over about 14.5 at cruise. I'm still just under 350CHT (according to my gauge and what average has been for cruise at 3500) and my oil temps haven't been above 190 at any point. They usually hover around 180, again on my gauges.
I guess I could try a 47 idle to see how that played out. 50 is the lowest I've gone so far since it seemed to do well. |
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W1K1 Samba Member
Joined: March 04, 2004 Posts: 4921 Location: Southern AB
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Fri Jan 13, 2012 12:55 pm Post subject: |
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Yes, that's where I started a while back. The 50's dialed in nice without the main stack, but like I said I never did drop below that.
Have you gotten 16-17 at cruise out of your type 3? |
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MURZI Samba Member
Joined: August 25, 2005 Posts: 5063 Location: Madisonville, La
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Posted: Fri Jan 13, 2012 12:57 pm Post subject: |
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Just curious, what is your elevation? _________________ 62 vert
2276
Tim’s welded heads
45 Dells
A1 sidewinder
Fk44 cam |
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mxracer Samba Member
Joined: April 09, 2011 Posts: 568 Location: NC
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Posted: Fri Jan 13, 2012 12:59 pm Post subject: |
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856 ft according to google.
I'm guessing (cause this is my first real round with duals in a type 3) that between the stock size valves, 30mm vents, short stacks, short manifolds, and short air cleaners it's a little "out of the norm". |
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MURZI Samba Member
Joined: August 25, 2005 Posts: 5063 Location: Madisonville, La
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Posted: Fri Jan 13, 2012 1:03 pm Post subject: |
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Just wondering because I went through HELL try to tune some 36 dells a few weeks back and wound up waaaaaay fatter than your jetting. I am at sea level. Crazy......
Your jetting seems spot on to what it should be...mine wasn't.
http://www.thesamba.com/vw/forum/viewtopic.php?t=489666&highlight=dell _________________ 62 vert
2276
Tim’s welded heads
45 Dells
A1 sidewinder
Fk44 cam |
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