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 Post Posted: Wed Jul 11, 2012 7:01 am 
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Thanks Barry, that was going to be one of my next questions. So anything past a square T slot and I will have to drill the butterflies.
I don't know if you can tell from the photos. The outer air bleeds are just blanked off.
Also more photos.

Image




This photo posting isn't that hard.
Cheers Colin


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 Post Posted: Wed Jul 11, 2012 7:10 am 
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If I can get the idle speed I want with out exposing to much TS I'm all good. If I can't I will have to drill the butterflies. Is that right.
I think/hope I will be ok because where it idled before I was happy with the TS exposure.

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Cheers Colin


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 Post Posted: Wed Jul 11, 2012 11:04 am 
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Colin, You can also plug those bleed holes with a 10/32 brass set screw if you have them as the HP bleeds are not cheep or you don't even have to plug them at all as there is no hole in the metering block gasket..I had 2 HP Dominators and still have one but there quality control is in the toilet as far as the T-slot is concerned. You maybe lucky but you may have had the slot exposed a lot before and didn't know it :-s ..My 1150 Non HP had just a touch of the slot exposed and after I was done with the on and off thing I ended up with 4 7/32 holes in the blades to get it to idle where I wanted it to.
Now on my 1250 HP that is another story altogether..30% slot showing with the blades closed completely!! So ended up with just a 1/2 turn on them to keep it from sticking and started drilling the blades..That was time consuming.. Big motor requires a lot of air..

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 Post Posted: Wed Jul 11, 2012 11:15 am 
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Colin after looking at your metering blocks you need to make sure that your IJ doesn't go too far into that hole. You have to make sure that there's plenty of room on the inside for idle/transition fuel to enter that idlewell.

You might be OK but I just thought I'd bring this up as it's possible to have that IJ in too far. If you need to have it back out some, then you can use a small punch to "ding" the top thread on the set screw to hold it where you need it in that threaded hole. You can also use that trick on Ebleeds. ;-)

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 Post Posted: Wed Jul 11, 2012 11:35 am 
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After look at it again it may be the picture but here is what they should look like just flush with that cavity.
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 Post Posted: Thu Jul 12, 2012 4:29 am 
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ken & Barry,
you had me worried so I went and double checked the IJ. I used a bottoming tap, and only tapped just deep enough. They are only 5mm or 3/16 long so they are definetly not to deep.
With the blades I had them fully closed then I just opened them half a turn of the speed screw. In that position there is no TS showing.
I took these photos with my mobile phone, thats why there not so good.
Cheers Colin.


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 Post Posted: Thu Jul 12, 2012 6:09 am 
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Hey Your IJ looks just fine! Your lucky the have a Main Body like that!!!!!! Mine was showing with them completely closed. I am thinking your not going to have to drill the blades at all and maybe lengthem some O:) Here is what I had to work with :-
Image

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 Post Posted: Thu Jul 12, 2012 8:00 am 
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Colin, here's a little tip for ya on the T slots. Get that carb on the engine and running at idle BEFORE you do anything with the T slots!!!

Once you have idle speed where you want it, then pull the carb back off and check the T slots. If they aren't showing at all, then take a scribe and scribe a line where the blade is in the bore at the T slot. That way when the blade is open you can see exactly where that slot is. If it needs to be lengthened, then don't go any further than that scribed line, THEN you can file a little off the blade in that area to expose the slot. This way you're leaving yourself sort of a safety zone down the road, ie, you can replace those blades, but you CAN'T put material back in that slot! ;-)

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 Post Posted: Fri Jul 13, 2012 6:51 am 
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Hey Ken,
Once I get the idle speed where I want it, and I pull the carb and decide I need to adjust the TS exposure. If I lengthen the slot as you suggested, does the idle speed change?
Higher, lower or no change?
Do I need to consider anything?

Beretta wrote:
Looking good Colin, You want to mark your Speed screws where full closed position is and then crank them open to where there is a square T-slot is showing.
This makes it easier to see where you are when doing the first start up. That way you will know it you will need some by-pass air or not...
Another tip is to remove the acc-pump cams after you get some heat in it as that makes it much easier to make adjustments to the idle...
Good luck!! and again Nice job =;


Barry,
so by removing the pump cams. I will be able to see the transition from idle to transfer slot without influence from the acc pump. Is that what you mean?
Cheers Colin.


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 Post Posted: Fri Jul 13, 2012 7:24 am 
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Quote:
Barry,
so by removing the pump cams. I will be able to see the transition from idle to transfer slot without influence from the acc pump. Is that what you mean?
Cheers Colin.



You got it..Also it helps keep it clean as your not squirting gas in it..And yea you may have a little hesitation but not to worry...This worked real good for me and ken as he was just tuning his new alky carb...

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 Post Posted: Fri Jul 13, 2012 12:59 pm 
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SGDCXCVI wrote:
Hey Ken,
Once I get the idle speed where I want it, and I pull the carb and decide I need to adjust the TS exposure. If I lengthen the slot as you suggested, does the idle speed change?
Higher, lower or no change?
Do I need to consider anything?


Depends on how close you were on the tune to begin with. But not much at all on the speed screws if any. It will probably have more effect on the idle mix screws than the speed.

Just a little note here, when we're talking about the T slot exposure keep in mind that there's a "perfect world" and also there's "reality", ie, sometimes we have to make do with something that isn't perfect. That being said, if you're a little more open than you want to be on that slot, then I'd try adjusting on it BEFORE you go drilling holes, etc to see if you can get it good enough to do what you want to do. If not then explore the options that you may have.

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 Post Posted: Fri Jul 13, 2012 3:58 pm 
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Cool, thanks guys. I'm going to fire it up when I get home from work this afternoon. Saturday is only half a day. I will post results.
Cheers Colin


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 Post Posted: Wed Jul 18, 2012 6:26 am 
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Well guys, I've got a update. Seems I wasn't as prepared as I thought, I didn't have as much fuel as I thought. I guess it had evaporated.
I did get it started, it fired up straight away, got it up to temp and set idle speed. I took the carb back off and checked the transfer slot. I ended up with the front TS square and the rear slot I could just see. So I was pretty happy with that.
I did what Barry suggested, remove the pump cams (man, it makes it hard to start)
I then hooked up my laptop to check AFR at idle. I found it was a bit too lean to where I wanted to be and the log jumped a lot.
That got me thinking about sample rate. At 1400 idle the engine fires 11 times a second and I had the sample rate at 100/sec. I then changed the sample rate to 25/sec and the log smoothed out, remember I'm only looking at AFR at idle.
So two questions, to richen the afr at idle, should I decrease the IAB or increase the idle feed restriction?
And what do you guys think about idle/AFR sample rate.
I'm picking up some more fuel so I can do some more this weekend.
Cheers Colin.


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 Post Posted: Wed Jul 18, 2012 7:05 am 
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Colin,
While you have the pump cams off you can still pump the accelerator pump arm by hand before you try to start it.
Doesn't take usually take much on the front pump arm to get it started.

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 Post Posted: Wed Jul 18, 2012 8:17 am 
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Where is your IAB now??? Yes to lower IAB will fatten it up..But if your in the low 50's you can go up on the IJ say 2#'s (If your at .040 go to .042) and start over..
I found out that one size up makes a difference but 2 #'s you will see a more noticeable difference.. Ideal IAB is 60ish or so but don't get crazy to get it there as we are only talking idle...
Yes by the time your done you should have a box full if drilled bleeds =;

Oh and like Donee said just hit the acc pump with your finger a couple times ;-)

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