Boost prepping RB Holley carb?

[djmtsu]

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?

[djmtsu]

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.

[FerociousP]

from a thread on the evil forum:

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/ (http://www.turbomustangs.com/forums/)

go to the carb boost section and you'll see what's involved. 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.

[jacobcartmill]

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.

[djmtsu]

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

[85rx-7gsl-se]

I am curious to see how this will stack up against my TII swap.

[djmtsu]

Hopefully we'll find out soon Nate!

[85rx-7gsl-se]

:D

[jacobcartmill]

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.


Now go away rotorless Haltech Troll


really

[djmtsu]

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.


really

Yes, really.

















































Do I smell smoke?

[jacobcartmill]

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.

[djmtsu]

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.

[jacobcartmill]

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 :)

[85rx-7gsl-se]

Jacob you do know some turbo folks run 0 split timing up top right?

[jacobcartmill]

Jacob you do know some turbo folks run 0 split timing up top right?


how much split are you running?

[85rx-7gsl-se]

I would have to double check. I think its 15 down low and 10 up top. However some higher hp guys do run zero split up top and we actually discussed the zero split topic at the tuning seminar at DGRR a few years back.

[djmtsu]

Thanks Nate.

[rotarycrazy]

I will sell you a 650DP holley thats boost prepped :)

[djmtsu]

Too much carb for a 12a stock ports.

Thanks though!

I can sell you a Racing Beat Holley carb and intake :)

[djmtsu]

Quoted from 7club-

The reason you lock the timing on a first gen dizzy blowthrough is the fact that the dizzy will NOT retard the timing under boost. At 10-15 psi under full boost you would only need a maximum timing of 5-10 degrees. So you lock the timing to where you would need the it at full boost.

[FerociousP]

Quoted from 7club-

The reason you lock the timing on a first gen dizzy blowthrough is the fact that the dizzy will NOT retard the timing under boost. At 10-15 psi under full boost you would only need a maximum timing of 5-10 degrees. So you lock the timing to where you would need the it at full boost.

That's just leading timing, and actually you lock it so it doesn't advance timing while the engine is under boost.

Trailing timing and split is obviously a source of contention among people. Everyone has a preference and an idea of what is safe. If that's what allegedly works, then go with that.

[730RWHP12A]

Jacob you do know some turbo folks run 0 split timing up top right?

a whole bunch of folks, with good results too .

the turbo blow through holley pro's are CSU carburetors. they make over 1,000hp with a blow through holley, reliably :)

[730RWHP12A]

Quoted from 7club-

The reason you lock the timing on a first gen dizzy blowthrough is the fact that the dizzy will NOT retard the timing under boost. At 10-15 psi under full boost you would only need a maximum timing of 5-10 degrees. So you lock the timing to where you would need the it at full boost.

why would you believe anything you read on the 7 club? anybody with knowledge has been banned from there!

no, wrong. you lock/ weld the distributors centrifugal weights so as the engine revs up the timing dosnt advance.
why would mazda retard the timing on an n/a car?:beatdeadhorse5:

lock the dist. set your timing at 10 degrees advance and your done.:sifone:

[djmtsu]

why would you believe anything you read on the 7 club? anybody with knowledge has been banned from there!

no, wrong. you lock/ weld the distributors centrifugal weights so as the engine revs up the timing dosnt advance.
why would mazda retard the timing on an n/a car?:beatdeadhorse5:

lock the dist. set your timing at 10 degrees advance and your done.:sifone:


That is basically what I posted from the 7club, you just stated it differently.

[djmtsu]

a whole bunch of folks, with good results too .

the turbo blow through holley pro's are CSU carburetors. they make over 1,000hp with a blow through holley, reliably :)

And they won't touch the RB Holley I have, they were the first people I contacted.

I am boost prepping the Nikki, so this thread can be closed anyway.

[jacobcartmill]

cliff notes:

1. i know some people have great results running zero split, 15* split, and hell, even negative split.
2. nate is running 15* of split in the midrange, probably where he's making peak torque.
3. 730whp12a just posted what we all already know -- run 10* of advance
4. so, run ~10* advance, 10* split, get your intercooler and carb setup nicely, and have fun tuning. :)

(and don't run more than 10 psi on 93 octane gasoline with those 9.4:1 rotors!)

[730RWHP12A]

And they won't touch the RB Holley I have, they were the first people I contacted.

I am boost prepping the Nikki, so this thread can be closed anyway.

well ,if you want a nikki turbo hat, let me know, i have some real nice ones :)

RCC member discount too!

[djmtsu]

well ,if you want a nikki turbo hat, let me know, i have some real nice ones :)

RCC member discount too!

Will do. What kind of price are we talking?

On your website they are $100, but on eBay they are $120.

How much for RCC?

[730RWHP12A]

Will do. What kind of price are we talking?

On your website they are $100, but on eBay they are $120.

How much for RCC?

$95.00 with free priority shipping for any RCC member

[djmtsu]

That is a good deal. I'll jump on that soon. I am waiting for my turbo and downpipe right now.

[rx71king]

no, wrong. you lock/ weld the distributors centrifugal weights

you weld the weights on your dizzy...?i don't believe you.....

[730RWHP12A]

you weld the weights on your dizzy...?i don't believe you.....

i do :) it doesn't take alot of extra time and that way it cant move no matter what.

[rx71king]

i do :) it doesn't take alot of extra time and that way it cant move no matter what.

you don't have to weld to lock the dizzy . or take it apart...:biggthumpup:

[ArmyOfOne]

So how do you do it rx71king?

[730RWHP12A]

So how do you do it rx71king?

thats what im wondering...