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  #16 (permalink)  
Old 08-28-2011, 05:57 PM
B.A.M.F
 
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hehe i like shiny stuff too

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Old 09-07-2011, 08:30 AM
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I like this. Really. Having ran the Weiand and 660's back in the day, I know it can be a bit difficult to deal with. Not impossible, but I did curse at it a few times.

If I had the jack, I'd buy the kit just to check out how it really runs on a stocker w/highway gears. Would be awesome to "faux rod" the ol' lady's dd. I can see the looks already from the other soccer moms

Cool twist on an old favorite. Good luck with this. I'd buy it. Eye candy is great when it is also useable, especially on an actual street car.
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  #18 (permalink)  
Old 09-07-2011, 08:55 AM
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Why not divide it into "8 plenums" and just use it with carbs that have equal venturis and a mechanical linkage (along with 2 accelerator pumps and 4 corner idle etc). Essentially you would create an IR system from 2 4bbl holleys, which could REALLY make an improvement down low. Tuning would be easier than it is right now as well since you could tune each cylinder individually and there wouldn't be an uneven mix of cylinder pairings.

you could also try altering your cam timing on each lobe to compensate for the firing order, but that would take more R&D and $$$ than I think you would want to invest for a street application.
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Old 09-07-2011, 06:22 PM
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I started out intending to do an IR system, but you have some problems there. One is that you basically need the same CFM capacity to feed one cylinder as two. That is non-intuitive, but it is how the Weber IR systems work. Each throat is set up at about 300CFM for an independent runner V8. That means you need Dominators to get the airflow you need. With the pairing-up business, I can use much less expensive carburetors and still have the capacity to feed the cylinders. Plus I get progressive throttle - one lower-capacity venturi is open at part-throttle, so it gets better velocity. The second venturi is not open until the engine can use the extra airflow, so it does not kill the velocity.

With 660 center squirters, each cylinder would only be connected to a venturi capable of flowing 165CFM. That is definitely not enough. Also, even the 660s open the primaries some distance before opening the secondaries. That can be fixed with custom linkage, but the airflow problem cannot.

There actually were Dominators made for IR systems in the '70s. Grumpy Jenkins ran them, but could not get the top end power he wanted. The carbs are no longer available. IR Weber setups also are known to limit the top end to around 550HP even with their biggest setup. IR systems do make good bottom end, but the larger-throat setups do kill some of it off due to low velocity through the one big venturi at low RPM.
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  #20 (permalink)  
Old 09-07-2011, 08:13 PM
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Quote:
Originally Posted by L79vette
Each throat is set up at about 300CFM for an independent runner V8. That means you need Dominators to get the airflow you need.
If EACH runner gets 300 cfm, you'd need two 1200 cfm carbs!

What Weber has 600 cfm flow? The approximate total cfm for different IDF carbs:

40mm= 212 CFM

44mm =290 CFM

48mm = 340 CFM

Even if each throat is set up at about 150 cfm for an independent runner, that is still 1200 cfm total. But you'll have a hard time convincing me you need 2400 cfm combined.
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  #21 (permalink)  
Old 09-08-2011, 08:13 PM
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Not so on the Weber CFM. Weber 48's are 350 or so CFM _per_venturi_. You can read all about this on GT40s.com, where they build Weber IR motors that run out of breath around 500-550HP with 48 IDAs.

That thing you said about needing 2 1200 CFM carbs is precisely what I was driving at when I said I needed two Dominators. Like I said, it is quite non-intuitive, since you can feed a 500HP engine with a 750 Holley on a single plane. That's because the cylinders share the airflow through the venturis. Once you start dividing things up, you need to keep a certain capacity visible to each cylinder.

Last edited by L79vette; 09-08-2011 at 08:31 PM.
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Old 09-15-2011, 08:05 AM
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Anyone tried these things on yet?
Seen the site, price moves around a bit (trying to find the price point?)

Still no pics or vids of these parts at work on a car? Wondering if it generated much interest.

L79, you still workin on this design or any other creative stuff?
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  #23 (permalink)  
Old 09-15-2011, 07:12 PM
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Hoping to get pics and video of the El Camino this weekend. A customer with a '63 Corvette is sending a picture too.

We've also got some more experiments to come that will trade off some bottom end to gain some top end.
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  #24 (permalink)  
Old 11-26-2011, 02:25 PM
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Anyone have any news or info on this? I see that there is a website that references "out of stock" for the products and wonder if anyone on here has any experiences with this set up??

I am interested in buying the tops and carbs to go onto my Weiand Tunnel Ram, but want more information prior to committing to the $$$.
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  #25 (permalink)  
Old 12-17-2011, 06:11 PM
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Well, I sprung for the $$$ and I am not all all disappointed. I opted for the tops and carbs only since i already had the tunnel installed. I had been running the weiand tunnel for about 2 years and was never happy until now. This set up is the cats meow (I really wanted to say the "cats ***" but didn't know if that was acceptable). Did I say that out loud?

Anyway, back to the results. I can now stand on the throttle from a standstill and have heart stopping response. There is absolutely no hesitation or stumble at any speed.

I had only two concerns. The first is that the new plenums get icy cold and depending upon the humidity, they sweat. I am pretty happy that the charge is so cold though.

The second and only other topic is, that I could not get a steady vacuum reading when trying to read each carb separately from the base vacuum port. The needle was briskly fluctuating back and forth with a 10 hg swing. Then I thought to tee the two ports together and then got a steady reading that I could set the idle mixture with.

At this point, I am thrilled with the set up, and as a side note, whenever I had a question or concern, Wayne was extremely responsive. So much so that he responded to an email of mine over the weekend within 10 minutes.

If any of you are considering this, I highly recommend it and would be happy to discuss my experience with you.

Steve
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  #26 (permalink)  
Old 12-17-2011, 10:35 PM
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i would like more information on this mainly for my own education ut also bc im starting a job building and machining engines and the employer would be interested in something like this
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  #27 (permalink)  
Old 12-18-2011, 03:47 AM
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Quote:
Originally Posted by UPandComing
i would like more information on this mainly for my own education ut also bc im starting a job building and machining engines and the employer would be interested in something like this
More information on the patent pending design here:

**********************

Last edited by 68NovaSS; 12-18-2011 at 10:29 PM. Reason: Advertising. Please see: commercial posting guidelines.
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  #28 (permalink)  
Old 12-18-2011, 11:57 AM
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what about this?

Hi Gentlemen,

Mr. Fixit, thank you for the nice testimonial. I am glad it worked out so well for you, especially given the king-size cam you are running.

I am still working on this. The foundry is making more tops, and there will be more stock in January.

The price is a barrier I know, but the margins are pretty low already. With the custom castings and custom carbs, my cost is high too.

To address this, here is something I am thinking about: You could use Holley 1850 carbs, if you were willing to do some significant work on them. This involves drilling precise hole sizes, plugging the power valve, and removing the secondary spring. You would have to drill the emulsion holes in the main well, and the high speed air bleed holes. If I could sell just the top castings, and a kit with numbered drill bits and a power valve plug to modify 1850's that someone already had, I could sell it for***************** Maybe even a little less.

Do you guys think people would be interested in this as an alternative? My thinking so far has been to make eveyrthing as easy as possible, and not have people rummaging around in the guts of the carburetors.

Last edited by 68NovaSS; 12-18-2011 at 10:30 PM. Reason: Advertising. Please see: commercial posting guidelines.
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  #29 (permalink)  
Old 12-18-2011, 12:15 PM
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I guess my main concern, putting myself in your shoes, would be making sure the customer knows they can't just bolt on any carb and have it work great. I mean the main selling point is how well it works. Maybe if you provided a guide to doing the modifications to the carb that came with the top casting?
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  #30 (permalink)  
Old 12-18-2011, 01:22 PM
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Quote:
Originally Posted by Valkyrie5.7
I guess my main concern, putting myself in your shoes, would be making sure the customer knows they can't just bolt on any carb and have it work great. I mean the main selling point is how well it works. Maybe if you provided a guide to doing the modifications to the carb that came with the top casting?
Yes. If I set up something for people to modify their own carburetors, it will include step-by-step instructions with pictures. I would still be nervous about it, because so many people buy used carbs that have been modified by folks who are very short of clues about what they are doing.

I've also thought about providing the carburetor mods as a service. It isn't very easily reversible either though. If someone changes his mind, he's going to have to tap the air bleed holes, and the emulsion holes, and to go screw-in restrictions. I could have folks do that from the beginning, but it is more complexity and cost than drilling the opening. Too many complications in all this.

Last edited by L79vette; 12-18-2011 at 01:40 PM.
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