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Does anyone know of a carb shop in Ventura County, CA or the San Fernando Valley, CA that can do this? Have two 1050 Dominators on a 540 with 8/71. I know that Performance Carb and Speed in Ontario, CA can do it, but I was wondering if there was a shop closer to where I live in Ventura. I'm also considering mailing them somewhere, so my second question is who do you recommend nationwide? Anyone is Havasu?

Before anyone recommends I just square up the jets and remove the power valve, I am also considering that as well. In this post I'm just interested in finding someone that boost references dominators. Thanks for your help.
 

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Does anyone know of a carb shop in Ventura County, CA or the San Fernando Valley, CA that can do this? Have two 1050 Dominators on a 540 with 8/71. I know that Performance Carb and Speed in Ontario, CA can do it, but I was wondering if there was a shop closer to where I live in Ventura. I'm also considering mailing them somewhere, so my second question is who do you recommend nationwide? Anyone is Havasu?

Before anyone recommends I just square up the jets and remove the power valve, I am also considering that as well. In this post I'm just interested in finding someone that boost references dominators. Thanks for your help.
I think Alexi over at Boostpower is close to you, and will do it right.
 

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Does anyone know of a carb shop in Ventura County, CA or the San Fernando Valley, CA that can do this? Have two 1050 Dominators on a 540 with 8/71. I know that Performance Carb and Speed in Ontario, CA can do it, but I was wondering if there was a shop closer to where I live in Ventura. I'm also considering mailing them somewhere, so my second question is who do you recommend nationwide? Anyone is Havasu?

Before anyone recommends I just square up the jets and remove the power valve, I am also considering that as well. In this post I'm just interested in finding someone that boost references dominators. Thanks for your help.
So you believe you are still pulling a vacuum at WOT with two dominators and that is closing the power valves ?
Did you check manifold vacuum at WOT with a gauge ?
 

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Discussion Starter #5
So you believe you are still pulling a vacuum at WOT with two dominators and that is closing the power valves ?
Did you check manifold vacuum at WOT with a gauge ?
Well, in theory, yes, but I'm not sure. I haven't put a guage on it at wide open throttle. Do you think I will be pulling a vacuum? I honestly do not know.

I talked to Teague and they have never boost referenced and said they never will. They can set the carbs up with power valves and jets based on my engine specs. Still waiting to hear from Boost Power. I am not set on either method.
 

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So you believe you are still pulling a vacuum at WOT with two dominators and that is closing the power valves ?
Did you check manifold vacuum at WOT with a gauge ?
LOL....unless the blower has no rotors in it you certainly will not have vacuum @ WOT! The reason for running power valves on a blower motor is so you can still run a leaner jet on the primary side at idle and low speed. You boost reference them simply because once the blower motor makes boost.....there is no vacuum to open the power valve as originally designed. Jocko
 

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LOL....unless the blower has no rotors in it you certainly will not have vacuum @ WOT! The reason for running power valves on a blower motor is so you can still run a leaner jet on the primary side at idle and low speed. You boost reference them simply because once the blower motor makes boost.....there is no vacuum to open the power valve as originally designed. Jocko

Vacuum holds the power valve closed. The power valve opens when manifold vacuum drops below the number on the power valve.
This is the problem when power valves are discussed is most don't understand how they work.

When I ran carbs years ago and the same old boost referencing discussion came up I checked the WOT manifold vacuum below the carbs and above the blower. 540 CI , Hampton 8-71 , two 850 Holley carbs. Showed 0 vacuum at WOT. That showed that the power valves were open. Boost referencing would have served no purpose.

So now I'm waiting for the inevitable, " sometimes you can be making boost and still show vacuum " :rolleyes:

Damn am I glad I don't run carbs anymore
 

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Think about the whole purpose of a power valve in the first place. It has nothing to do with WOT.
 

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Think about the whole purpose of a power valve in the first place. It has nothing to do with WOT.
Certainly, but the discussion was about the need for boost referencing which would only apply if the engine was pulling enough vacuum to close the power valve(s) at WOT. I have never seen that happen yet.
 

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Certainly, but the discussion was about the need for boost referencing which would only apply if the engine was pulling enough vacuum to close the power valve(s) at WOT. I have never seen that happen yet.
They don't actually close at WOT...they never open and it happens all the time. We're not talking about manifold vacuum, we're talking about vacuum below the carb and when the blower starts building boost, it can create more vacuum under the carb @ WOT, not less, and then the power valves never open like they're supposed to. They're supposed to stay closed till vacuum drops under higher engine load, then when vac drops, they open and add more fuel. It's an enrichment circuit. "Boost referencing" uses the positive pressure in the manifold to overcome the additional vacuum under the carb and allows the PV's to work like they're supposed to.
 

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We're not talking about manifold vacuum, we're talking about vacuum below the carb and when the blower starts building boost, it can create more vacuum under the carb @ WOT, not less, and then the power valves never open like they're supposed to.
Yes I understand the power valves read vacuum from the carb base. I checked it and read 0 vacuum @ WOT so I knew the power valves were open. The Hampton blower was 28% overdriven. Damn roots blower couldn't make a significant boost number no matter how much Overdrive I put to it. I Sold it and would never own one again.

I know what I read on the gauge. As usual we disagree and that's fine, no worries. :)hand

I don't know why I responded to this thread. I swore off carbs 14 years ago.

I guess I had, https://www.youtube.com/watch?v=5XcKBmdfpWs
 

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...
So now I'm waiting for the inevitable, " sometimes you can be making boost and still show vacuum " :rolleyes:
The important question would be, what is the absolute pressure under the blower when the pressure above the blower (under the carbs) is at the PV value? When speaking of PV's, who cares what the pressure under the carb is at WOT??? I really don't think that was the topic up for discussion.

I'm only guessing that, if Teague never uses BRPV's that they're definitely choosing PV values that correlate to a certain pressure in the manifold (under the blower) and not relying on the stamped value. Can't see any other way to get the enrichment to occur when ya want it to. What do you think?
 

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LOL....unless the blower has no rotors in it you certainly will not have vacuum @ WOT! The reason for running power valves on a blower motor is so you can still run a leaner jet on the primary side at idle and low speed. You boost reference them simply because once the blower motor makes boost.....there is no vacuum to open the power valve as originally designed. Jocko
Need to correct the last sentence in my previous post. Basically, delete that last sentence......it was late and it was incorrect. That being said, boost referencing a pair of blower carbs is very easy to do. Google the subject and there are a few step by step video's out there that show you how to drill a port into the PV cavity. This modification very simply opens the power valve when the BLOWER makes boost, period.
Mark, we all know you don't like carbs or blowers. However, there are way more of us that still run them and quite sucessfully! Whether you couldn't make boost with your previous blower setup is irrelevant. The original poster simply wants to boost reference his carbs, more than likely for the reason I posted above......idle and low speed conditions from the ability to run leaner primary jets. That's it.......let's not turn this beat to death subject into a pissing match again as in the past.
Jocko
 

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Discussion Starter #16
For anyone: Does boost translate directly to vacuum? In other words is 6 psi of boost going to pull 6 lbs of vacuum?


Sent from my iPhone using Tapatalk
 

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For anyone: Does boost translate directly to vacuum? In other words is 6 psi of boost going to pull 6 lbs of vacuum?
No. They're completely unrelated.
 

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steelcomp was here
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Yes I understand the power valves read vacuum from the carb base. I checked it and read 0 vacuum @ WOT so I knew the power valves were open. The Hampton blower was 28% overdriven. Damn roots blower couldn't make a significant boost number no matter how much Overdrive I put to it. I Sold it and would never own one again.

I know what I read on the gauge. As usual we disagree and that's fine, no worries. :)hand

I don't know why I responded to this thread. I swore off carbs 14 years ago.

I guess I had, https://www.youtube.com/watch?v=5XcKBmdfpWs
Sounds to me like you just don't know what the heck you're doing. :dunno:
 

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Dan Davinci 281-964-7782..worth a call
I'll second the Davinci recommendation. Dan did a 1050 drag dominator off a 540 powered door car capable of mid/low eights for me years ago, and I was quite impressed with the results.
 

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One thing to consider; if you're running sideways mounted carbs on a roots blower you really need to square up the jetting and not mess with PV's. Your engine will thank you.
 
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