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 Post Posted: Fri Jun 01, 2012 8:35 pm 
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I have purchased a 2 circuit alcohol 1050 built for my sb chev and it runs lean with a .210 jet
.032 mab 1295 deg f. to richen it up I went to .225 and .023 mab temp came down to 1250 deg f.
It has allways had a hole when you stand on it real quick so I richened up iab from .036 to .026
idle temp was 700 now down to 550 bog still there, bigger squirter .067 no difference.
My son recorded it and it revs initially (pump squirt) then falls into hole for about 2 seconds then it
recovers.
To me it seems like it has a poor signal, the boosters seem different it has one hole about .200 and two smaller holes 90 degrees either side of the lager hole.
Ran last meet with my old alcohol 950hp bad air it went 9.32 changed to 1050 went 9.52 and 1 mph slower. temp with 950 was 1220 with .156 jet.
Thinking of trying some holley boosters I have 8 hole @ .098.

mab 32 now 23
iab 36 now 26
ifb 60 now 67 but have not run since increasing ifb
e-holes 5@ .040
kill .028

Thanks guys
Steve...


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 Post Posted: Fri Jun 01, 2012 8:43 pm 
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Something is seriously wrong. Thats the most screwed up jetting spec Ive ever seen. Are you sure its those jets for those functions?


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 Post Posted: Fri Jun 01, 2012 8:46 pm 
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your telling me! thats how I got it and been changing it as per his recommedations.
Think I need a refund.


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 Post Posted: Fri Jun 01, 2012 8:59 pm 
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There's big thread on here where I had the same problems with an 1150 methanol carb. And you think 1295* is lean? I've seen mine over 1325*+.

So what's the rest of the fuel system like? :-k

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 Post Posted: Fri Jun 01, 2012 9:03 pm 
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ss436 wrote:
your telling me! thats how I got it and been changing it as per his recommedations.
Think I need a refund.

Is it a new carby from a business? Obviously the fuel system can keep up because its working with the other carby. I would set it up with some conventional boosters and follow the thread on here. Or send it back and get a stock holley FROM holley.


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 Post Posted: Fri Jun 01, 2012 11:02 pm 
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Oh, and did I mention that those temps were on EIGHT MILE PASSES? O:)

Here's the link to my "never ending saga" of methanol Dominators.

viewtopic.php?f=6&t=1840

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 Post Posted: Fri Jun 01, 2012 11:22 pm 
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Well heres one for ya. we ran a methanol injected engine for years in the same configuration. It was always rebuilt at the end of the season (drags) by the same guy. Always had the same tune just pilled it for air density changes. Then the engine builder changed and the same engine ran a much hotter exhaust temp 1450f (not 1280) it went the same down the track, it just had hotter exhausts. Still made the same plug readings etc. still the same injection tune. And you wonder why I dont give a stuff about EGT's.


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 Post Posted: Fri Jun 01, 2012 11:40 pm 
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Carb is from US builder built for my combo, fuel pump is a belt drive ron's vane pump 4 idle
10 down track.
My friend has a quickfuel converted carb and when you just crack the throttle the boosters start
to flow a lot with my it needs a lot more thottle then starts to dribble.
Shrinker your right about egt's can be a funny thing, I need to get a o2 sensor and start data logging.

Steve...


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 Post Posted: Fri Jun 01, 2012 11:54 pm 
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With your setting in the carby I would expect that. the Idle system is sucking a lot of fuel, its robbing the booster of flow down low thats why the booster is late. the level in the well is all going to the idle circuit.
Well you make your own decision about the validity of the 'Built for my combo' scene. The other carby is better, so its not too well built is it. If someones going to claim they can build a carby to a combo then they better dam well do it. Otherwise shut up and call it a work in progress. Nothing wrong with that approach.

A stock 8x .098' hole booster has an area equivalent to a single 0.277' hole thats going to allow the fuel from the well to get out of the booster. At the moment you have a possible restriction there. You havent said what size the other holes are in the booster and you havent measured the booster feed tube. The thing is the stuff upstream from the main jet has to be bigger than the main jet other wise the main jet is just there for decoration.
Borrow your mates carby.


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 Post Posted: Sat Jun 02, 2012 12:43 am 
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Booster tubes are .200 i asked same question about being smaller than jet, big hole drilled in booster
is oval .226 x .214 and the two smaller holes are .080.
I feel that the large hole in the booster wont have as good of a signal as compaired a series of small holes under the booster step.
Carb does not milk oil on idle and gains heat quickly, dont even use my lean-out valve as for my 950 it drinks the fuel.

Steve


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 Post Posted: Sat Jun 02, 2012 12:56 am 
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Booster with one large hole .226 and two smaller holes .080
Could this be why it needs a big jet. carb was wet flowed and came with .210 jets
This has been a work in progress allright wasted a few meetings doing what changes they say.

Steve...


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 Post Posted: Sat Jun 02, 2012 1:18 am 
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Well if the booster tube is .200" then the main jet is not the controller is it. The booster tube is doing it.
The carby builder should know that jets in sequence need to be 4 times the area of one another to make one jet the controller. What that means is the booster tube needs to be 4 times the area of the main jet in order for there to be no interaction or restriction to the main jets ability to be a proper controller of AFR. With your setup the booster tube is the jet and that means the emulsion is nearly useless. the e-bleeds are not in the lowest pressure point there between points, a totally different scene.
With what you have if you want to make it richer chuck the main jet away. That's not going to be a tenable situation is it?
A stock design works, your mates quickfuel is a stock design. Granted, passing enough methanol for high power is difficult with a Holley but I've never seen anyone have to resort to the setup you have to make it work. Thats new one on me if its right. But I'll guarantee going with conventional design is there for a reason, its not like were in the 1910's trying to work this stuff out.


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 Post Posted: Sat Jun 02, 2012 1:21 am 
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ss436 wrote:
I feel that the large hole in the booster wont have as good of a signal as compaired a series of small holes under the booster step.
Steve

That would be true.
ss436 wrote:
Carb does not milk oil on idle and gains heat quickly, dont even use my lean-out valve as for my 950 it drinks the fuel.

well then the 950 is not right either.


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 Post Posted: Sat Jun 02, 2012 4:53 am 
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I don't understand everything I know about methanol and EGTs either as I have two different methanol setups that yield different EGTs.

I've got two 750 methanol carbs originally done by Rupert that I run on a sheetmetal intake and the single 1150 Dominator carb that I run on a Dart intake that I ported myself. My engine is an 18* 434 SBC BTW. The dual 750s run much cooler EGTs than the 1150 but both carb setups are real close performance wise? In fact, the Camaro I had last year ran the quickest it ever ran on the single Dominator setup.

Early on with the 1150 I was never able to get it rich enough to slow it down though. I can do that now but it took a great deal of custom work to be able to do that and EGTs still are higher than what I see with the dual 750s. Sometimes I wonder if the Dominator isn't atomizing the fuel enough and elevated EGTs are because of that, ie, raw fuel burning in the exhaust?? :-k

Ennywho, your pump setup and down track pressures sound about right for those single needle seat bowls. I run dual needle seat PCI Super Bowls on my Dominator and I get by with 6.5psig fuel pressure on both setups. My system will idle around 2psig and it's regulated down track to around 6.5psig. Pump bypass pressure is set at 10psig on the BLP internal bypass belt drive pump.

Oh, and you have a PM. ;-)

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 Post Posted: Sat Jun 02, 2012 7:44 am 
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Looks like a hack did that carb.


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