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Old 06-22-2011, 04:57 PM   #1
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Default Boost prepping RB Holley carb?

Anyone ever tried. I have read the instructions widely available online about how to boost prep a Holley--> http://www.hangar18fabrication.com/blowthru.html

Those instructions are for a double pumper, but I don't know if the same rules apply to the RB Holley carb.

I would like some insight so I can choose a direction to go with this POS FB

This would be a blow through set up of course. Anyone?






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Old 06-23-2011, 10:37 AM   #2
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I sent a Tech email to Racing Beat yesterday, still no word back. Usually they reply very quick to my questions. I can't be the only person to ask if their carb can be boost prepped.
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Old 06-23-2011, 10:52 AM   #3
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from a thread on the evil forum:

Quote:
whooaoaaaaaaaa, the RB holley will NOT be good for boost. it's wayyy off for even a good starting point. even the 4150 model double pumpers have to be put threw a process of milling, changing parts, different gaskets, blocking off passages, drilling, etc... before it will accept boost. do not boost that holley.

start off witha real holley... ohhhh i dunno 600cfm 4150 double pumper. get center hung nitrophyl floats, jet extensions, mill the choke... ahhhh shit. if your serious start a thread about the proper holley to use for boost.

no wait, go here www.turbomustangs.com/forums/

go to the carb boost section and you'll see what's involved.
Quote:
I boosted a holley on a 12A. Its not a simple thing. You need a manifold referenced power valve,4 corner idle,adjustable air bleeds, custom downleg annular discharge boosters,the nitrophyl floats, jet extensions,custom bowl venting and a few other things....a carn hat as well. Even then you will get marginal streetability. I own 6 books on modifing holleys. I also spent close to 500.00 on the carb (things I couldnt do myself). If you really want to pursue this I would suggest a webber to start with. But honestly when your done for the same money you could have fuel injection. And much better streetability. With my holley boosted 12a it would drive ok and then without warning take off like a bat outta hell...I mean rip your hands off the wheel fast. This sounds kewl but without warning it wasnt. No one could drive the car but me. Even with professional help a carburated turbo will never be as good as FI. Im sure someone will argue with me on this,but I spent almost 4 yrs with this set up and really know what Im talking about. I now have the same car with a FI turbo 13B and am sooo much happier. Just my advice,good luck.
I didn't read your link about the boost prepping so there may be different ways of doing things, these are just posts from members who have experience with carbs. I'm interested to hear what RB has to say about it though. They may have a solution.
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Old 06-24-2011, 10:43 AM   #4
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serious questions/commentary:

1. are you going to run an intercooler?
2. who is tuning it?
3. this guy that pauly referenced put it nicely, and so did the guy in your email from racing beat.
4. after really thinking about this, i'm coming to the conclusion that a) this is much more work and expense than you think it is, and b) the results are going to be worse than you think they are.

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Old 06-24-2011, 10:55 AM   #5
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Quote:
Originally Posted by jacobcartmill View Post
serious questions/commentary:

1. are you going to run an intercooler?
2. who is tuning it?
3. this guy that pauly referenced put it nicely, and so did the guy in your email from racing beat.
4. after really thinking about this, i'm coming to the conclusion that a) this is much more work and expense than you think it is, and b) the results are going to be worse than you think they are.
1. yes
2. me
3. Not using the RB Holley carb anymore. The Nikki can be boost prepped and can flow enough to make over 200hp+
4. a) no it isn't. I have a spreadsheet, and already have 75% of the required parts b) the results are going to be better than you think they are.

Now go away rotorless Haltech Troll
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Old 06-24-2011, 11:41 AM   #6
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I am curious to see how this will stack up against my TII swap.
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Originally Posted by Wesley Carlock aka RotoriousRX7
"Rotarys come with built-in traction control, its called no torque"
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Old 06-24-2011, 12:03 PM   #7
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Hopefully we'll find out soon Nate!
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Old 06-24-2011, 12:27 PM   #8
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Quote:
Originally Posted by Wesley Carlock aka RotoriousRX7
"Rotarys come with built-in traction control, its called no torque"
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Old 06-24-2011, 12:39 PM   #9
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Quote:
Originally Posted by djmtsu View Post
1. yes
2. me
3. Not using the RB Holley carb anymore. The Nikki can be boost prepped and can flow enough to make over 200hp+
4. a) no it isn't. I have a spreadsheet, and already have 75% of the required parts b) the results are going to be better than you think they are.
1. okay, intercooler is good. details of the intercooler setup?
2. how much boost do you plan on running?
3. are you going to do any boost activated timing retard?
4. i have a lot of spreadsheets.

Quote:
Originally Posted by djmtsu View Post
Now go away rotorless Haltech Troll
really
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Old 06-24-2011, 12:52 PM   #10
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Quote:
Originally Posted by jacobcartmill View Post
1. okay, intercooler is good. details of the intercooler setup?
2. how much boost do you plan on running?
3. are you going to do any boost activated timing retard?
4. i have a lot of spreadsheets.
1. No details. Core likely smaller in size than Paul's.
2. 6-8
3. No. The timing will be locked in the dizzy. 15 leading 10 trailing
4. So do I.

Quote:
Originally Posted by jacobcartmill View Post
really
Yes, really.

















































Do I smell smoke?
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Old 06-24-2011, 02:50 PM   #11
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Quote:
Originally Posted by djmtsu View Post
1. No details. Core likely smaller in size than Paul's.
2. 6-8
3. No. The timing will be locked in the dizzy. 15 leading 10 trailing
4. So do I.



Yes, really.

















































Do I smell smoke?
1. i wouldn't go any smaller than paul's IC.
2. 6-8 psi sounds good
3. can you clarify leading 15 trailing 10? you need at least a 10* split for boost.
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Old 06-24-2011, 05:02 PM   #12
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Quote:
Originally Posted by jacobcartmill View Post
1. i wouldn't go any smaller than paul's IC.
2. 6-8 psi sounds good
3. can you clarify leading 15 trailing 10? you need at least a 10* split for boost.
15 leading 10 degrees trailing (locked dizzy, no advance) is what I have been told by 5 different people running boosted 12a's. I am still looking into it.

The trailing isn't really doing much with my Direct Fire set up.

I should have kept my massive FMIC. Oh well, they're cheap.
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Old 06-24-2011, 06:04 PM   #13
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Quote:
Originally Posted by djmtsu View Post
15 leading 10 degrees trailing (locked dizzy, no advance) is what I have been told by 5 different people running boosted 12a's. I am still looking into it.

The trailing isn't really doing much with my Direct Fire set up.

I should have kept my massive FMIC. Oh well, they're cheap.
look into it a lot. if it's only a 5 degree split (that's what it looks like from your post) that may be enough split for 6-8psi, but that's pushing it, especially if you have very coarse fuel control. the trailing plugs need to fire ~10* behind the leadings.

what exactly do you mean your trailing ignition isn't doing much with your direct fire? it needs to be doing a lot. trailing ignition is very important. you have to ignite the other end of the long rotary combustion chamber, and it needs to happen at a specific time --~10-12* after the leadings fire. feel free to bring up any valid arguments for this.

i'm not trying to be a smartass here. i'm only posing these questions to help you, so do a lot of research and post a good reply
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Old 06-24-2011, 07:05 PM   #14
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Jacob you do know some turbo folks run 0 split timing up top right?
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Old 06-24-2011, 07:31 PM   #15
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Quote:
Originally Posted by 85rx-7gsl-se View Post
Jacob you do know some turbo folks run 0 split timing up top right?

how much split are you running?
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