Boosting Holley Carb??? Confusion
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Boosting Holley Carb??? Confusion
Ive posted about this a couple of times...and ive never gotten any answers...so i figured i would try once again...i have a Holley 600cfm double-pumper carb and im trying to boost prep it for a Garret T04B turbo.....to my understanding im supposed to change out the floats..but to what?
main questions are:
what do i change the floats too?
do i need a dual feed fuel line? and if so what happens to the return?
what size butterflys?
and any other advice on the carb....im getting ready to drop about $1700 on my turbo FB project and i want to make sure i get all the necessary things so that i can get it running....once running ill buy the additional misc items to tune it better.....any advice will be greatly appreciated as well...if u need to know more information on my setup just pm me or ask in the thread....ill try and stay in touch with this thread as much as possible...but being in Iraq has its disadvantages at times....
thanks to anyone that can help me out....and if working ill will have this car at a Raleigh, NC car meet....thanks again....parker
p.s. yes im retarded when it comes to carb's....im more of a FI person
main questions are:
what do i change the floats too?
do i need a dual feed fuel line? and if so what happens to the return?
what size butterflys?
and any other advice on the carb....im getting ready to drop about $1700 on my turbo FB project and i want to make sure i get all the necessary things so that i can get it running....once running ill buy the additional misc items to tune it better.....any advice will be greatly appreciated as well...if u need to know more information on my setup just pm me or ask in the thread....ill try and stay in touch with this thread as much as possible...but being in Iraq has its disadvantages at times....
thanks to anyone that can help me out....and if working ill will have this car at a Raleigh, NC car meet....thanks again....parker
p.s. yes im retarded when it comes to carb's....im more of a FI person
#5
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The floats need to be changed to a solid type. Also, you need to use a RRFPR (rising rate fuel pressure regulator) with a fuel pump than can exceed the boost pressure that your going to use +7 psi. For every 1 psi of boost, you need 1 psi of fuel pressure to force the fuel into the pressurized fuel bowls.
I don't know if you know this, but a RRFPR generally works on a 1:1 ratio. You set the base fuel pressure when the engine isn't on boost, then as boost rises, you get 1 psi more fuel pressure for every 1 psi that boost goes up.
I'm not totally sure about your fuel line question, but I would assume that the single fuel line is fine. And as for the butterflies, I dont quite understand what your asking. The butterflies are a set size for a certain sized carb. They can't be changed without changing the size of the barrels.
I don't know if you know this, but a RRFPR generally works on a 1:1 ratio. You set the base fuel pressure when the engine isn't on boost, then as boost rises, you get 1 psi more fuel pressure for every 1 psi that boost goes up.
I'm not totally sure about your fuel line question, but I would assume that the single fuel line is fine. And as for the butterflies, I dont quite understand what your asking. The butterflies are a set size for a certain sized carb. They can't be changed without changing the size of the barrels.
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yes run a dual feed line off the regulator. the return stays the same as it comes off the regulator as well (you NEED an aftermarket boost sensitive reg).
floats need to be nitrophyl. holley sells these, switch to center hung floats as well and get jet extensions. you need to remove the choke and mill down the horn or you will get turbulence of airflow and it will be the sux.
go ahead and remove the secondary pump arm as it will actually be too much fuel coming in at once. grab a 10.5 pv to start off with and work your way down if neccessary. GET THE HOLLEY COMPLETE JET KIT YOU WILL NEED THIS!!!!
also, you need to completely seal the carb. there are multiple ports where boost can creep out and this = bad. once you get it cranked and all if you are having a lean idle issue then drill out the IFR's and put small restrictors in the primary side air bleeds.
once you have come this far, ask more questions.
floats need to be nitrophyl. holley sells these, switch to center hung floats as well and get jet extensions. you need to remove the choke and mill down the horn or you will get turbulence of airflow and it will be the sux.
go ahead and remove the secondary pump arm as it will actually be too much fuel coming in at once. grab a 10.5 pv to start off with and work your way down if neccessary. GET THE HOLLEY COMPLETE JET KIT YOU WILL NEED THIS!!!!
also, you need to completely seal the carb. there are multiple ports where boost can creep out and this = bad. once you get it cranked and all if you are having a lean idle issue then drill out the IFR's and put small restrictors in the primary side air bleeds.
once you have come this far, ask more questions.
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