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 Post subject: BLP 5124 blocks
 Post Posted: Sun Jun 10, 2012 10:48 pm 
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Joined: Fri Feb 17, 2012 8:09 pm
Posts: 166
Location: Maryland
I installed BLP billets in my 80186-1 Dominator. I've been trying to get the idle clean, but it's still on the rich side. Current set up is:
IFR 040
IAB 066
TSJ 055
MAB .028
MJ 92
Emulsion holes
026
P
026
P
P
Mixture screws are 1.5 turns out. T-slots are square. The engine will idle at 1100 with light pressure on throttle. I don't have to feather it to keep it running.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Sun Jun 10, 2012 11:54 pm 
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Posts: 24
Location: Central Oregon
Hi Ron, just for comparison I have an older 1050 with 750 blocks and I think a .055 tsj, .038 ifr, and a .076 iab. It wont idle cold and pops a little in the shut down area so maybe a little lean, I'll try a .070 iab to see how it works but crisp as can be and comes up on the brake quick! Good luck

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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 4:57 am 
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Joined: Sun Nov 11, 2007 10:33 am
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Location: Montgomery, Alabama
Ron back your front and rear blades off 1/4 turn and lean your screws in some more.

It will work just fine with the slots less than square.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 7:19 am 
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Location: Florida
Don't be afraid to go down a little more on the idle bleed if needed, each one can be a little different. Run the engine cold up to 2000 RPM out of gear, put your finger over one or two idle bleeds. The RPM should pick up. Do it again with the engine warm, it should not pick up or even slightly lower if the idle jet and bleed are close to size to have enough fuel for the transition circuit. Once you can do this the mixture screws usually end up 1-1 1/4 turns out, but anywhere from 3/4 to 1 3/4 will do.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 8:56 am 
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Joined: Fri Feb 17, 2012 8:09 pm
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Location: Maryland
Thanks for all the suggestions.

I forgot to mention in my original post that I got this carb with a .125 hole in each primary blade on the wrong side of the shaft. Nomad suggested the possibility of turning them around to correct the hole location, but I haven't done that. It also has BLP banjos and inserts, so it's not a 750 anymore.

Mark, I hope your feeling better everyday. When you say go down on IAB, do you mean smaller? It acts fat now.

I'll try suggested stuff, but only one at a time. Looking over my old Tuner notes I came across one where he told me that the secondary slots don't have to be the same as the primaries. Tuner's comments on that are posted on page 3 of the sticky about tuning t-slots


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 11:01 am 
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Location: Florida
Idle jet and bleeds need to be set for the needs of the transition circuit, if you try the test I laid out above it will give you an idea which way to go. Idle fuel is further leaned by the mixture screws, so you adjust them as needed for idle. Is the timing lock out on your engine?


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 11:55 am 
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Location: Maryland
Timing is locked.
Is there a ratio of sorts for the bleed/jet adjustment? Like 2:1 ie 004 bigger bleed along with 002 smaller jet.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 1:25 pm 
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You try to fix the idle jet size, work the idle air bleeds from about .060 to .075. If you have to go above .075 drop the idle jet size .001 to .002, below .060 add .001-.002.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 2:34 pm 
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At 2000 rpm, covering the 4 idle bleeds dropped it to 1500 instantly and I cut it off before it killed the engine. I'll go up in bleed size and try again.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 3:40 pm 
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Location: Maryland
Drilled 4 @ .072, turned the mixture screws in to 1.250 and test results were the same.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 3:54 pm 
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Location: Rochester, NY
Ron - I think Mark said only cover 1 or 2 of the idle air bleeds. If you cover all 4 it will go way rich and do what you experienced.

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Rochester, NY
Quick Rod 130C
Super Comp 130C


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 4:13 pm 
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Location: Maryland
mslayton wrote:
Ron - I think Mark said only cover 1 or 2 of the idle air bleeds. If you cover all 4 it will go way rich and do what you experienced.

Mark, you're right! IAB's at .076 and covering 1 the R's dropped 500. Covering 2, the R's dropped 500 quicker.

I guess it's time to start reducing the IJ. That might have to wait til tomorrow.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Mon Jun 11, 2012 4:47 pm 
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Location: Maryland
On second thought, I'll move the mixture screws in and see if it responds before messing with the IJ's.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Tue Jun 12, 2012 3:19 pm 
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Location: Maryland
I've made a few changes but blocking a IAB still kills 500 rpm. This where I'm at:
IJ .035
IAB .076
TSJ .055
MAB .028
MJ 92
Mixture screws at 3/4 out.
I'm thinking an .080 IAB and then .031 IJ. You like that plan? These numbers seem a little extreme from all the others I've read about.


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 Post subject: Re: BLP 5124 blocks
 Post Posted: Tue Jun 12, 2012 5:21 pm 
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Location: Florida
How many turns out are the mixture screws? Also, make sure you don't have a leaky PV gasket. One other possibility, some carbs have trouble getting the square vacuum port in the main body to seal right against the metering block at the bottom of the emulsion well. On those you can take some gas tank epoxy, fill the hole, and file it smooth once it's dry.


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