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What would be good Holley carbs to use on a 460 cid BBC with a 871 blower. It will be a river deal in a Hondo flatbottom.
 

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What would be good Holley carbs to use on a 460 cid BBC with a 871 blower. It will be a river deal in a Hondo flatbottom.
if its a stock 460?...thats alot of blower!...also...IMO, flatbottom's are not too good for the river!...during the summer, (especially on weekends) the waverunners churn the hell out of the water!...is it a jet or v-drive?...750/850 DP, mech sec are good carbs...just my .02 cents :)

FastRat
 

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"It's HONDO, honey"
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Two dominators. Run it rich. Lean will burn it up, rich keeps the blower rotors cool.
 

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What he said...

and, big ass fuel lines and a screen filter like a System1(not a canister)

I'm running 97's square
What are your particulars???? I am just getting ready to take my new motor out,. I am running 572 w/10-71, 9.5;1, intercooled, and boost activated water/alcohal injection, 32 degrees w/ hunt mag, 20 lbs of boost, Dart 360's. I have a set of 1290 king demons. No power valves, stock air bleeds to start, 96 squared on jets. I am runnig product engineering 450 gph pump and reg.(-12 fuel line w/ -8 to each bowl) I plan to run 114 octane, 7200 -7500 rpm, between 32%-37% in the v drive, in 19 tunnel. How is my start up tune in relation to yours.

Thanks, Steve
 

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"It's HONDO, honey"
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What he said...

and, big ass fuel lines and a screen filter like a System1(not a canister)

I'm running 97's square
What he said....:D
Big carbs with little lines is a oxymoron. The only "necking down" of volume should be at the jets.

Two 1050 will do just fine. You'll see that the price of two dom's is a gasser but blowers tend to do that... If your one of the few that take the time and do it right.

:D example, save 500 run little 4100 series carbs, runs to lean no matter what, motor burns up, How much you got in the motor besides the intake and blower? Its a gross reality and I'll admit I've fell victum to things like this many of times.

obnoxious001 and VDRIVERACING are creditable guys listen what they have to say :)hand

Obnoxious how's the cam business?
 

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Discussion Starter #8
A little more information: The engine will have about 7.8 to 1 comp. with a solid flat tappet cam, steel 990 GM heads and max rpm will be about 6500. The fuel will be pump 93 octane and boost will be 10-11 pounds. The gears in the V drive will start at about 18% with a 2 blade prop,(size to be determined). The owner didn't want to use dominators unless absolutely necessary. 4150's are available up to 1000 cfm, wouldnt that be enough for 460 cid. I use 1050's on my 548 cid deal with a 1071 and they work great. Just wondering if he could get by with the 4150's.
 

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A little more information: The engine will have about 7.8 to 1 comp. with a solid flat tappet cam, steel 990 GM heads and max rpm will be about 6500. The fuel will be pump 93 octane and boost will be 10-11 pounds. The gears in the V drive will start at about 18% with a 2 blade prop,(size to be determined). The owner didn't want to use dominators unless absolutely necessary. 4150's are available up to 1000 cfm, wouldnt that be enough for 460 cid. I use 1050's on my 548 cid deal with a 1071 and they work great. Just wondering if he could get by with the 4150's.
I ran 491ci bbc 8.25:1, 6-71 14lbs boost,7500 rpm w/25's in the box,11 1/4x16, worked 990's with a set 830cfm 4150's.

we also ran a 461 BBC 11 1/2 x15, 7200 rpm w/37s in the box, w/1050 dominators, all other info the same, and in the same boat . both set ups ran flawless, and about the same speed. You can do it w/ either one, but I would prefer the dominators, more options for more power later.
 

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Do you guys think it is necessary to boost reference or use Holley's blower carbs?
I have had both, boost referenced dominators, and not. I think it is a lot easier to just remove the power valves,block em off, and jet up 8-10 sizes. I have never owned a set of "blower" carbs, 12 blower motors between my dad and I, all reg 4150's, or 4500's, (427-605 ci)only one was boost referenced. I am sure there some improvements w/ blower carbs, but we never had trouble tuning reg carbs for eac application. Just my opinion, Good Luck.., Steve
 

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What are your particulars???? I am just getting ready to take my new motor out,. I am running 572 w/10-71, 9.5;1, intercooled, and boost activated water/alcohal injection, 32 degrees w/ hunt mag, 20 lbs of boost, Dart 360's. I have a set of 1290 king demons. No power valves, stock air bleeds to start, 96 squared on jets. I am runnig product engineering 450 gph pump and reg.(-12 fuel line w/ -8 to each bowl) I plan to run 114 octane, 7200 -7500 rpm, between 32%-37% in the v drive, in 19 tunnel. How is my start up tune in relation to yours.

Thanks, Steve

How are you getting 20 lbs of boost on a 10:71 with 572 cui? I have my 10:71 15% over and it will only make 8lbs. Threw my research it looks like I need atleast a 14:71 but I will probably buy the 5.0L whipple.
 

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Do you guys think it is necessary to boost reference or use Holley's blower carbs?
I have used 750's on a 468 that were boost referenced by John Avery and they worked really nice. They really purr and allow long periods of idle and tranistion easily from idle to low range RPM. The problem I had before the boost ref circuit was that in order to put enough fuel in the engine to run at high RPM without detonation, I had to jet it so high that it would load up when idling and foul the plugs.

If you want more boost, and sooner, the dominators are the only way to go. That also applies if you have big inches. The little carbs will hold you back on boost and top end, but if you already own them, they will work. If you use the 750's, I highly recommend having a boost reference circuit added.
 

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What are your particulars???? I am just getting ready to take my new motor out,. I am running 572 w/10-71, 9.5;1, intercooled, and boost activated water/alcohal injection, 32 degrees w/ hunt mag, 20 lbs of boost, Dart 360's. I have a set of 1290 king demons. No power valves, stock air bleeds to start, 96 squared on jets. I am runnig product engineering 450 gph pump and reg.(-12 fuel line w/ -8 to each bowl) I plan to run 114 octane, 7200 -7500 rpm, between 32%-37% in the v drive, in 19 tunnel. How is my start up tune in relation to yours.

Thanks, Steve
Well, Steve, you have a pretty radical setup there! My gear is mild compared to yours - 468 with a teenie 8-71 and a mechanical fuel pump and no cooler. I run 34 degrees, 110 leaded, same RPM range, but only 22 gears... Of course, my boat is actually "in the water" most of the time!
 

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I have used 750's on a 468 that were boost The problem I had before the boost ref circuit was that in order to put enough fuel in the engine to run at high RPM without detonation, I had to jet it so high that it would load up when idling and foul the plugs.
this is pretty interesting Bill, considering that main jets have ZERO effect on the idle air/fuel ratio! And Avery knows that. There are reasons for boost referencing, but idle isn't one of them. I am certain that he didn't for other reasons, even though that may have been 1 of your problems when you gave him the carbs, boost referencing them didn't cure your idle problem.



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this is pretty interesting Bill, considering that main jets have ZERO effect on the idle air/fuel ratio! And Avery knows that. There are reasons for boost referencing, but idle isn't one of them. I am certain that he didn't for other reasons, even though that may have been 1 of your problems when you gave him the carbs, boost referencing them didn't cure your idle problem.
I was using the term "idling" broadly as that part throttle condition when tooling around in no wake zones. Not technically idling, yes, but the point was low RPM where a recreational boat spends a lot of time, but thanks for the clarification.
 

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I have the same question guys...not real keen on blower tune ups...I'm putting together a 489 BB Chev, Canfield 310's, flat tops (haven't cc'd yet but I think around 9:1 w/119cc) hyd roller 643/622 248/260 112, BDS 871, under 10# boost, pump gas deal. This is going in a 68 ElCamino with a 5 spd, strictly hot rod-go to Bob's Big Boy on Friday night kinda cruiser. Needs to be drivable but obviously needs to walk the walk with the 871 stickin outa the hood (and my name on the engine:|err) I'd like to run a pair of sideways 850's or???. Dom's are out of the question. Mech fuel pump, maybe back up w/ electric. Input would be appreciated.
Edited to add: Cam is for not more than 6000 rpm
 

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This is from the BDS web site. Should get you close. Dominators seem to preffered by many but I have had luck with 4150 carbs but I am just a garage hack and do not build professionally. I also prefer to boost reference unless it is a drag race apllication.

A: {(CID x RPM) ÷ 3456} x {Boost ÷ 14.7) + 1} = CFM required
 

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I have the same question guys...not real keen on blower tune ups...I'm putting together a 489 BB Chev, Canfield 310's, flat tops (haven't cc'd yet but I think around 9:1 w/119cc) hyd roller 643/622 248/260 112, BDS 871, under 10# boost, pump gas deal. This is going in a 68 ElCamino with a 5 spd, strictly hot rod-go to Bob's Big Boy on Friday night kinda cruiser. Needs to be drivable but obviously needs to walk the walk with the 871 stickin outa the hood (and my name on the engine:|err) I'd like to run a pair of sideways 850's or???. Dom's are out of the question. Mech fuel pump, maybe back up w/ electric. Input would be appreciated.
Edited to add: Cam is for not more than 6000 rpm
I have a similar setup, and just run the mechanical pump. You don't need dominators to make it run on the street.
 

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How are you getting 20 lbs of boost on a 10:71 with 572 cui? I have my 10:71 15% over and it will only make 8lbs. Threw my research it looks like I need atleast a 14:71 but I will probably buy the 5.0L whipple.

Last time I spoke w/ the blower shop, we were maxing the blower out at 24% o.d., w/18-20 lbs of boost. They recommended that as the max efficiency of my set up.. Maybe it wont make it, We havent tested yet, just going off there numbers. Different cam, heads, blowers will give different boost values. Amd yes, I know more boost doesn't always make more power, sometimes just more heat...I am running an intercooler, and a boost referenced water/alcohal injection for cooling, and enrichment. I would really like to make the h.p. and torque I need at 15 lbs of boost.
steve
 
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