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 Post Posted: Fri Feb 03, 2012 8:05 am 
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I wanted to give those bowels a try but can't find a set but still looking.. =;
I would like to try a set of those bottom feed N&S but don't see them on your web sight..

After looking at that vid again....The first one the fuel get's really low and so does the second one but not as bad as the first...We need some kind of sensor in there to see just how low the fuel get going down track...Also what kind of fuel is that with no color,unleaded?? Also is that there 3 circuit block?

I think Ken issue with that carb is he can't make it rich enough to slow it down :-# ..

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 Post Posted: Fri Feb 03, 2012 11:08 am 
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Barry is correct. Keep in mind that these are methanol carbs.

Early on with that first 1150 I could never get it rich enough to slow it down even with no jets in those 5/16 x 32 holes. That and EGTs were much hotter than I'd seen with the dual Rupert 750s I had run on that engine before.

Turns out that the crosswells in the metering blocks are .206 and the stake tubes are .213 but having said that, the crosswells are still the "restriction" in the circuit which effectively makes them the jet.

So this "new to me" dominator has some rather large holes in the banjos, some of your boosters with mods and also major mods to the mainwells and crosswells in the metering blocks. All this is an effort to try to get beyond the former .206 crosswell bottle neck.

I'll let you know how all that works for me later this summer. ;-)

But back to your new needle seat, are they viton or titanium, SS, etc?? If those things will work with methanol then that would simplify things as far as delivery to the fuel bowl goes and also be much cheaper than what these PCI bowls cost (if you can find them).

FYI, most guys that I know of that run single Dominators on methanol with single needle seat bowls have to run fuel pressure up between 10 and 12 psig down track in order to keep from running out of fuel. This usually requires a belt drive pump with a tunable bypass because of the variable pressure output requirement, ie, low enough at idle and part throttle to keep from blowing the needles off the seats but high enough down track to keep from running out of fuel. If your new NS will do what you say then the belt drive pump wouldn't be needed and a good electric pump should work fine.

Be interesting to see how this plays out. :-k

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 Post Posted: Fri Feb 03, 2012 5:43 pm 
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Beretta wrote:
After looking at that vid again....The first one the fuel get's really low and so does the second one but not as bad as the first..
It starts at a much higher level with the new design N&S. There is a white line on the bowl look at that on the 2 videos.


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 Post Posted: Fri Feb 03, 2012 6:09 pm 
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Fuel level was pushed up on the second only as a preventative measure, to protect the engine in the event it didn't work as planned. There is still some testing to do but it looks very promising. The first video with 5.9 psi is how it came off the car prior to the last runs, add g-forces and you wonder how the carb even works right.


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 Post subject: New Holley N&S Design
 Post Posted: Mon Feb 06, 2012 8:55 pm 
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Beretta wrote:
I wanted to give those bowels a try but can't find a set but still looking.. =;
I would like to try a set of those bottom feed N&S but don't see them on your web sight..

After looking at that vid again....The first one the fuel get's really low and so does the second one but not as bad as the first...We need some kind of sensor in there to see just how low the fuel get going down track...Also what kind of fuel is that with no color,unleaded?? Also is that there 3 circuit block?

I think Ken issue with that carb is he can't make it rich enough to slow it down :-# ..


Barry:

Please call about the bottom-feeds. Thanks for the reminder about our website - I keep forgetting to have the bf-info posted.

Concerning the videos - as Mark said; the 1st vid is straight off the dragster. The 'relatively' low float level was used in an attempt to prevent 'slosh' due to g-forces. (As viewed in other videos we've taken.) The fuel level gets ridiculously low during the run. As you note; the float drops quicker in the 1st vid due to aeration. We're pretty sure that we've remedied the slosh issue, and the lower pressure/less aeration should help keep the jets covered with mostly liquid. Testing later this week should show gains or losses. The fuel is c23. Yes; it is our wide 3-circuit block.


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 Post subject: New Holley N&S Design
 Post Posted: Mon Feb 06, 2012 9:05 pm 
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Ken0069 wrote:
Barry is correct. Keep in mind that these are methanol carbs.

Early on with that first 1150 I could never get it rich enough to slow it down even with no jets in those 5/16 x 32 holes. That and EGTs were much hotter than I'd seen with the dual Rupert 750s I had run on that engine before.

Turns out that the crosswells in the metering blocks are .206 and the stake tubes are .213 but having said that, the crosswells are still the "restriction" in the circuit which effectively makes them the jet.

So this "new to me" dominator has some rather large holes in the banjos, some of your boosters with mods and also major mods to the mainwells and crosswells in the metering blocks. All this is an effort to try to get beyond the former .206 crosswell bottle neck.

I'll let you know how all that works for me later this summer. ;-)

But back to your new needle seat, are they viton or titanium, SS, etc?? If those things will work with methanol then that would simplify things as far as delivery to the fuel bowl goes and also be much cheaper than what these PCI bowls cost (if you can find them).

FYI, most guys that I know of that run single Dominators on methanol with single needle seat bowls have to run fuel pressure up between 10 and 12 psig down track in order to keep from running out of fuel. This usually requires a belt drive pump with a tunable bypass because of the variable pressure output requirement, ie, low enough at idle and part throttle to keep from blowing the needles off the seats but high enough down track to keep from running out of fuel. If your new NS will do what you say then the belt drive pump wouldn't be needed and a good electric pump should work fine.

Be interesting to see how this plays out. :-k


I'd be interested to know how the 1150 runs this summer. Did you use a tapered or straight reamer on the mw's?

The new (prototype) needles are made from delrin, primarily for weight. I see no reason the n/s's will not work with methanol. If all goes well with track-testing; we'll be methanol testing with our big engine.

We tested an electric pump vs a belt drive pump with our engine at the low pressures. The pressure varied 0.9psi with the electric pump (steadily lowering as rpm's increased). The pressure varied only 0.2psi with the belt drive pump.


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 Post Posted: Mon Feb 06, 2012 9:53 pm 
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Hey Barry,

I run the bottom feeds in my dominator, and I definitely feel i saw an improvement. The AFR traces are smoother since adding them, I need to order me a set for my demon.

Here is a link to the bottom feed n/s on the website

http://blp.com/cart/index.php?main_page=product_info&cPath=65_108_268&products_id=578

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 Post Posted: Tue Feb 07, 2012 6:07 am 
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Thanks for the link.... ;-) Some how didn't see that..

Mike would you think a bowel extension will be beneficial with the 2 circuit metering blocks we are using? I would think the more fuel that is in there the better...

Another thing I have thought about is on the primary metering block to make the jets screw in on say a 45* angle pointing those jets down. :-k There would be less of an angle upon entry to the main well and also could help in flow some...

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 Post Posted: Tue Feb 07, 2012 8:48 am 
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Beretta wrote:
Thanks for the link.... ;-) Some how didn't see that..

Mike would you think a bowel extension will be beneficial with the 2 circuit metering blocks we are using? I would think the more fuel that is in there the better...

Another thing I have thought about is on the primary metering block to make the jets screw in on say a 45* angle pointing those jets down. :-k There would be less of an angle upon entry to the main well and also could help in flow some...


Some use bowl extensions and love them. We don't use them much at all (I can't remember the last time that we did). Yes they increase volume; however with proper fuel supply are not needed. If you use them; be sure to use correct length jets, squirter arms, bowl screws, etc.

We've tried the down-angle primary jet position and did not see much gain. (We've tried a wide/wild variety of jet positions with little verifiable gain.) We do position the jets as low as possible.


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 Post Posted: Tue Feb 07, 2012 10:57 am 
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As far as bowl volume think about this, with a larger bowl you have more room for fuel to slosh and churn. Having the ability to increase the volume of fuel through the N&S at a lower pressure and still control it I think is the right direction to go. Trying to correctly meter foam through a carb is much more difficult than liquid fuel.


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 Post Posted: Wed Feb 15, 2012 6:04 am 
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Mike/ Mark, Anything new with the new needle and seats??? Do anymore testing with them =; ...

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 Post Posted: Tue Feb 28, 2012 11:11 pm 
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OK I'm late to the party. I was making a BLP order and wondered if the bottom feed N&S need any special mods to the bowls?


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 Post Posted: Wed Feb 29, 2012 8:05 am 
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Not the bottomfeed, I have them in both of my carbs and have seen fuel curve improvements.

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 Post Posted: Thu Mar 15, 2012 7:38 pm 
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This is a Racepak screenshot from Mikes car, look at the fuel pressure. This is on a 6.83/199 run at SGMP....

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 Post Posted: Thu Mar 15, 2012 9:14 pm 
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Yeah this all "looks good" in a post but before I'd spring for a pair of $50 needle seats, I'd have to see these kind of graphs/results on a "Joe Average" door car running 6.50s in the eight mile! Sorry, but I'm not one of those that will "go off" on fishing expeditions on something that is "new". No offense Mike! But then again, I'm a pessimist and I'm always one to figure why it WON'T work before I put down money!

FYI, Bill Jones, whom I respect a lot (speed talk and Bonneville fame) posted some stuff years ago about fuel pressure and the HP that it would support with a single STOCK .110 Holley needle seat. He says that a single Holley needle seat will support like 350 HP at only 3psig. Iff'in you got two or those in a 4 barrel carb, then you could support 700 HP @ that same 3 pisg! And Bill also says a SINGLE .110 needle seat will support 600 hp at 6 psig and that means that a 4 barrel like a Dominator will support 1200 HP at that same 6 psig! And if you run dual carbs, you could support 2400 HP at that same 6 psig. So where does that put us with stock Holley .110 needle seats @ 4 psig?

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