Go Back   Rotary Car Club > Tech Discussion > Carburetors and Carb Tuning..

Carburetors and Carb Tuning.. All info about old school carb set ups..


Welcome to Rotary Car Club.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Reply
 
Thread Tools Display Modes
Old 06-22-2011, 03:57 PM   #1
djmtsu
My minds tellin' me no...
 
djmtsu's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (10)
Posts: 4,043
Rep Power: 21
djmtsu will become famous soon enough
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?






__________________
1976 Mazda Cosmo RX-5
1976 Mazda Cosmo RX-5
2003 Toyota Tundra TRD
2015 Toyota 4Runner SR5
djmtsu is offline   Reply With Quote
Old 06-23-2011, 09:37 AM   #2
djmtsu
My minds tellin' me no...
 
djmtsu's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (10)
Posts: 4,043
Rep Power: 21
djmtsu will become famous soon enough
Default

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.
__________________
1976 Mazda Cosmo RX-5
1976 Mazda Cosmo RX-5
2003 Toyota Tundra TRD
2015 Toyota 4Runner SR5
djmtsu is offline   Reply With Quote
Old 06-23-2011, 09:52 AM   #3
FerociousP
I-had-a-bad-experience...
 
FerociousP's Avatar
 
Join Date: Feb 2008
Location: M'boro
iTrader: (2)
Posts: 1,046
Rep Power: 18
FerociousP is on a distinguished road
Default

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.
__________________

'15 Juke Nismo
'06 MX-5 GT SOLD
'04 S Silver RX-8 GT Track Day Use SOLD
'90 Black TII vert w/ Sprint RE stock port/turbo DD dyno (242.6whp@5500rpm @12psi 8psi@redline) and (250ftlbtq@4800rpm @13psi) SOLD
'89 GTUs 6p TII SOLD, '87 sport SOLD, '79 SA stock SOLD
'91 B2600i 4x4 w/ Rx-8 LSD SOLD
FerociousP is offline   Reply With Quote
Old 06-24-2011, 09:43 AM   #4
jacobcartmill
Rotary Fan in Training
 
Join Date: Jun 2011
iTrader: (0)
Posts: 50
Rep Power: 0
jacobcartmill is on a distinguished road
Default

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.

Last edited by jacobcartmill; 06-24-2011 at 09:48 AM..
jacobcartmill is offline   Reply With Quote
Old 06-24-2011, 09:55 AM   #5
djmtsu
My minds tellin' me no...
 
djmtsu's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (10)
Posts: 4,043
Rep Power: 21
djmtsu will become famous soon enough
Default

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
__________________
1976 Mazda Cosmo RX-5
1976 Mazda Cosmo RX-5
2003 Toyota Tundra TRD
2015 Toyota 4Runner SR5
djmtsu is offline   Reply With Quote
Old 06-24-2011, 10:41 AM   #6
85rx-7gsl-se
Mod With The Least :P
 
85rx-7gsl-se's Avatar
 
Join Date: Feb 2008
Location: Manchester, TN
iTrader: (2)
Posts: 1,649
Rep Power: 0
85rx-7gsl-se is on a distinguished road
Default

I am curious to see how this will stack up against my TII swap.
__________________
Resident Post Whore
Polluting the environment one revolution at a time.

www.tennspeed.net
Quote:
Originally Posted by Wesley Carlock aka RotoriousRX7
"Rotarys come with built-in traction control, its called no torque"
85rx-7gsl-se is offline   Reply With Quote
Old 06-24-2011, 11:03 AM   #7
djmtsu
My minds tellin' me no...
 
djmtsu's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (10)
Posts: 4,043
Rep Power: 21
djmtsu will become famous soon enough
Default

Hopefully we'll find out soon Nate!
__________________
1976 Mazda Cosmo RX-5
1976 Mazda Cosmo RX-5
2003 Toyota Tundra TRD
2015 Toyota 4Runner SR5
djmtsu is offline   Reply With Quote
Old 06-24-2011, 11:27 AM   #8
85rx-7gsl-se
Mod With The Least :P
 
85rx-7gsl-se's Avatar
 
Join Date: Feb 2008
Location: Manchester, TN
iTrader: (2)
Posts: 1,649
Rep Power: 0
85rx-7gsl-se is on a distinguished road
Default

__________________
Resident Post Whore
Polluting the environment one revolution at a time.

www.tennspeed.net
Quote:
Originally Posted by Wesley Carlock aka RotoriousRX7
"Rotarys come with built-in traction control, its called no torque"
85rx-7gsl-se is offline   Reply With Quote
Old 06-24-2011, 11:39 AM   #9
jacobcartmill
Rotary Fan in Training
 
Join Date: Jun 2011
iTrader: (0)
Posts: 50
Rep Power: 0
jacobcartmill is on a distinguished road
Default

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
jacobcartmill is offline   Reply With Quote
Old 06-24-2011, 11:52 AM   #10
djmtsu
My minds tellin' me no...
 
djmtsu's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (10)
Posts: 4,043
Rep Power: 21
djmtsu will become famous soon enough
Default

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?
__________________
1976 Mazda Cosmo RX-5
1976 Mazda Cosmo RX-5
2003 Toyota Tundra TRD
2015 Toyota 4Runner SR5
djmtsu is offline   Reply With Quote
Old 06-24-2011, 01:50 PM   #11
jacobcartmill
Rotary Fan in Training
 
Join Date: Jun 2011
iTrader: (0)
Posts: 50
Rep Power: 0
jacobcartmill is on a distinguished road
Default

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.
jacobcartmill is offline   Reply With Quote
Old 06-24-2011, 04:02 PM   #12
djmtsu
My minds tellin' me no...
 
djmtsu's Avatar
 
Join Date: Feb 2008
Location: Murfreesboro, TN
iTrader: (10)
Posts: 4,043
Rep Power: 21
djmtsu will become famous soon enough
Default

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.
__________________
1976 Mazda Cosmo RX-5
1976 Mazda Cosmo RX-5
2003 Toyota Tundra TRD
2015 Toyota 4Runner SR5
djmtsu is offline   Reply With Quote
Old 06-24-2011, 05:04 PM   #13
jacobcartmill
Rotary Fan in Training
 
Join Date: Jun 2011
iTrader: (0)
Posts: 50
Rep Power: 0
jacobcartmill is on a distinguished road
Default

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
jacobcartmill is offline   Reply With Quote
Old 06-24-2011, 06:05 PM   #14
85rx-7gsl-se
Mod With The Least :P
 
85rx-7gsl-se's Avatar
 
Join Date: Feb 2008
Location: Manchester, TN
iTrader: (2)
Posts: 1,649
Rep Power: 0
85rx-7gsl-se is on a distinguished road
Default

Jacob you do know some turbo folks run 0 split timing up top right?
__________________
Resident Post Whore
Polluting the environment one revolution at a time.

www.tennspeed.net
Quote:
Originally Posted by Wesley Carlock aka RotoriousRX7
"Rotarys come with built-in traction control, its called no torque"
85rx-7gsl-se is offline   Reply With Quote
Old 06-24-2011, 06:31 PM   #15
jacobcartmill
Rotary Fan in Training
 
Join Date: Jun 2011
iTrader: (0)
Posts: 50
Rep Power: 0
jacobcartmill is on a distinguished road
Default

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?
jacobcartmill is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 03:02 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Hosted by www.GotPlacement.com
Ad Management by RedTyger