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 Post Posted: Sat Jan 14, 2012 12:52 pm 
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decided to go ahead and convert my 8896 3 circuit to a 2 circuit. got a set of 2 circuit metering blocks from ebay for $48.
they appear to be quick fuel metering blocks.

ordered some annular non-skirted boosters with 16 hole centers from BLP. was going to send throttle body to them
to have new boosters installed. figured what the hell, i have a small machine, will make my on annular booster install tool.

process to remove old and install new boosters seemed pretty painless.

i made a tool for lathe to hold brass inserts. found it easier drilling from the backside of set screw versus the front.

finished drilling and tapping metering blocks along with drilling and tapping throttle body this morning.

the only the issue i have right now, is that i too much transfer slot shown below throttle blades.
right now throttle blades are set for 1200 rpm on motor.

baseline settings i plan on using on my low 9 second 454
tsj = .050
ij = .040
eb= 2 @.029(broke my .028 bit)
iab= .070
mab=.030
kb=.028
pj = 96
sg = 96
no pv

i look forward to comments or issues you might have.
i have attached a link to my web album for all.

hoping to get back together this afternoon, and take a cruize down the road

thanks

https://picasaweb.google.com/1151214244 ... or2Circuit


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 Post Posted: Sat Jan 14, 2012 3:06 pm 
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How much is "too much" on the Tslot exposure? :-k

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 Post Posted: Sat Jan 14, 2012 3:33 pm 
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If you can close the throttle blades more you can add idle air bypass holes to get the idle back up.

T-slot jet - .050 may be a little small, but OK to start with, you will get surging at low throttle openings if it's too lean.

IJ - OK

IAB - OK

E-bleeds - don't be afraid to use .024 or .026

MAB - .030 will likely be too big, try a .024 or .026.

KB - OK

Jets will depend on fuel, anywhere from roughly 90-98. Regular Race gas is usually 92-94, oxygenated fuels can run higher.


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 Post Posted: Sat Jan 14, 2012 5:38 pm 
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[higher.[/quote]
Ken0069 wrote:
How much is "too much" on the Tslot exposure? :-k

almost an 1/8" on transfer slot

i can close throttle blades a little to reduce transfer slot exposure. would you recommend holes in butterflies for the air bypass?

i currently run 96 on the jets using sunoco supreme.


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 Post Posted: Sat Jan 14, 2012 6:45 pm 
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Picture #12 of the e-holes...there not drilled all the way threw so you just needed to plug the unwanted holes...
Something Tuner told me about the throttle blades is loosen the screws a touch and move the blades a little to get them to close better..If you just hold it up the lite and look from the top side you can see how much they don't close all the way..
That's an older style carb and the quality is a lot better on those compared to the HP models..

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 Post Posted: Sat Jan 14, 2012 7:06 pm 
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themadreefer wrote:
almost an 1/8" on transfer slot

i can close throttle blades a little to reduce transfer slot exposure. would you recommend holes in butterflies for the air bypass?


Drilling the butterflies is pretty much considered to be the nuclear option, ie, we don't "like" to do that, but sometimes a man has to do what a man has to do. If it's causing problems at part throttle then you may have to drill'em.

Try Barry's suggestion first to see if you can improve it any. Then, if you must, start out with a small drill. Somewhere around a 1/16" and do all 4 blades. Also, that hole should be in the proximity of the idle fuel exit hole and maybe a quarter inch off the edge of the blade. There should be a picture of this in one of the stickies. Don't quote me on this but if memory serves, those holes usually wind up close to .093 or so.

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 Post Posted: Sat Jan 14, 2012 10:17 pm 
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Here's about the size you want on that T-slot or maybe a touch more..
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 Post Posted: Sat Jan 14, 2012 10:23 pm 
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This maybe posted else where but you may want to try this as a controlled vacuum leak to help you get it to Idle after you set the T-slot with the speed screws. 1/4 pipe with a ball valve on the end..Can't take credit for this as It cane from Donee =; ...I used it and worked well when your working alone..
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 Post Posted: Sun Jan 15, 2012 7:17 am 
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after trying for an hour to close the gap on the transfers slots, finally figured it out, ended up hand sanding one of the butterflies, now i am able to adjust throttle manually to obtain the correct dimension for the transfer slot.

like the valve idea. will have to ponder over that this morning. i saw a post someplace were someone had placed air bleeds
at the base of the air cleaner stud. any thoughts on that idea?

hopefully today a i can get her fired up.

thanks again


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 Post Posted: Sun Jan 15, 2012 8:19 am 
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The best place to do it is in the throttle blades, placing the holes directly over the idle discharge ports is the best location. It places very high speed air hitting the fuel discharged from the idle circuit, improving atomization at idle. Unfortunately it's not easily adjusted as bleeds at the air cleaner stud. Start small, usually 3/32 in primary or primary and secondary is enough.


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 Post Posted: Sun Jan 15, 2012 9:34 am 
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10-4
thanks


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 Post Posted: Sun Jan 15, 2012 11:14 am 
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 Post Posted: Sun Jan 15, 2012 2:23 pm 
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Always remember to address the ignition timing used at idle etc. Timing greatly affects the vacuum and thus the blade position.


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 Post Posted: Sun Jan 15, 2012 3:00 pm 
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So did you have a chance to road test thing thing yet?? :-k If so, how does it do on the T slots? :-k

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 Post Posted: Mon Jan 16, 2012 5:29 am 
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no road test, got tied up with a small construction project at my house. hopefully in the next few days i will go road test,
actually pending weather, we night got racing Wednesday night.
I did however, get it back together and got her fired backup. All transfer slots are set right at .025 and she idles right at 1300-1400 rpm. Ended up drilling .086 hole in butterflies.

car idles much better, throttle response crisper, and my eyes do not burn(as much) when tinkering with car in shop.
i do have some more control with idle jet screws, not much more though. the primary idle jets will cause motor to lean out
,when they are screwed in. the secondary jets, really hard for me tell any change in motor, when adjusting these.

i know true test is only under a full load with carburetor. but a couple of dry hops in my driveway, all i can say is she reacts very differently(better of course).

can say this has been a project and experience worth doing.
enough rattling on, i need to head to work early this morning for safety training
have a safe work week
thanks


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