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hemi-itis

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Reply with quote  #1 
I found one of my issues.While at the track after making a pass and going 145 MPH we changed a pulley to go from 6 lbs of boost to 10 lbs.The back pressure separated the #7 cylinder slip tube!!! That slip joint has 2 inches of penetration!!! The MPH fell to 140 MPH.
   So now I question how the back pressure effects the AFRs and the AFR curve......



545 2nd gen hemi,1071 BDS stage 3 with 2 SV1s.Street driven ALOT!
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Reply with quote  #2 
NO exhaust out, no clean air in... so be careful.  Pressurized reversion can really cause havoc on your tuneup.
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Patrick James-President
hemi-itis

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Reply with quote  #3 
Will have dumpers on before the next outing.Inch by inch,,,,step by step. Will slip into the 5's on the next outing at an 1/8 mile track.
  I can't imagine the exhaust pressure required to separate that tube like that!!
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Reply with quote  #4 
Yea thats a bunch!!
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Patrick James-President
hemi-itis

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Reply with quote  #5 
Fabbed up some dumpers.At the 1/8 mile track it was 90* That day with 85% humidity....went 6.13 @ 113. I'm waiting for the fall air!  What is the best way to lean it out for street crusing? With the humidity it running fat!!
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Reply with quote  #6 
E me your 5 digit carb serial numbers, lets see your carb specs.
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Patrick James-President
hemi-itis

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Reply with quote  #7 
50371.Been very good after your rebuild and recalibration.If I wanted to lean out out across the board,,,,what would the proper proceedure be?
Now when I go to the track with dumpers open,what should I expect with the afr's? 34645096_10155854025814620_169307533498908672_n.jpg

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Reply with quote  #8 
OH that one is easy, just reduce the main jets two sizes all around.

That should drop you about .4-.5 of a ratio and see if the engine likes it.

NEXT:  Wow car looks great!!

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Patrick James-President
hemi-itis

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Reply with quote  #9 
Managed to go 9.3 @136+ with 3700 lbs.It must have been choking ! Installed a pair of dumpers and a cap in stainless and held the cap on with band clamps.

Attached Images
jpeg Carlisle 1018 006.jpg (132.26 KB, 1 views)
jpeg Carlisle 1018 008.jpg (149.76 KB, 1 views)
jpeg Carlisle 1018 009.jpg (176.76 KB, 1 views)
jpeg Carlisle 1018 010.jpg (204.04 KB, 1 views)
jpeg Carlisle 1018 017.jpg (145.66 KB, 1 views)

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Reply with quote  #10 
Awesome!
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Patrick James-President
hemi-itis

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Reply with quote  #11 
Well,not a good racing season.Only got out once in the spring to Atco and it was a cluster....,2nd time was in June at Chrysler Carlisle,there is an 1/8 mile track 20 minutes away called South Mountain.In the heat of 90* and 85%  humidity it ran 6.16 @ 113 FAT! It was so hot I didn't want to do a jet reduction in the direct sun.Best through the mufflers was 6.0 @ 117 so I was satisfied with the 16 uncapped.
  Few weeks ago I went to Atco with good conditions and increased the boost from 6 lbs to 10 lbs. Spun both passes and called it a day.The track just wasn't there for me and I was there by myself.
So I did not get my 8 second slip I was hoping for.
  One issue that still haunts me is intermittently when I lean into the throttle while street driving,say I at 2000 rpm and I want to speed up when I open the throttle it goes lean like the engine shut off and takes a few seconds for it to come back.A few times in the waterbox when I open to do a burnout it kinds shuts off and I have to let off the pedal and go WOT to avoid stalling.We had a similar issue coming off idle it would lean out,that was before I sent the carbs in for rebuild and recalibration.

New WO#50371
hemi-itis

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Reply with quote  #12 
Also,idle screws are just shy of 1 turn out.Should I increase the IAB to get the screws out ti 1.5 to 1.75?
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Reply with quote  #13 
Port 2 is your light part throttle fuel.  Its real small at .060   Drill them out to .070 and check the effect.  2 each on the primary side of each carb.   If it likes it and wants more, go to .082 next.SV1ports2012.jpg 



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Patrick James-President
hemi-itis

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Reply with quote  #14 
AWsome!! Thanks,will report back. 3.6.14 035.jpg 
hemi-itis

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Reply with quote  #15 
BTW that is an old pic...
2 questions
Is the block to main body gasket same as a dominator?
Besides wheel grease on the drill bit,how can I insure myself the body is clean of any drilling debris?
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