Tunnel ram or no tunnel ram...

MOPARMAGA

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And it’s annular… should I get one like this also?
The annular boosters took rat bastid a little bit of work on a lathe because blp haven't made banjos specifically for their main body .
Holley's main bodies use a square notch, blp has a round locator hole for the banjo, so it just needs to be milled a bit to get the banjo far enough in to be swedged in.
Blp will install them for you for an extra charge.
I think all carb builders would recommend annulars by now, they are far superior to a down leg, I can't even imagine how efficient they'd be on a tunnel ram,
I'm thinking you'd have a nice fuel fog.
But on a 750 main body I think it may hurt flow a bit but have a very good signal on those boosters
 
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Miszny

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The annular boosters took rat bastid a little bit of work on a lathe because blp haven't made banjos specifically for their main body .
Holley's main bodies use a square notch, blp has a round locator hole for the banjo, so it just needs to be milled a bit to get the banjo far enough in to be swedged in.
Blp will install them for you for an extra charge.
I think all carb builders would recommend annulars by now, they are far superior to a down leg, I can't even imagine how efficient they'd be on a tunnel ram,
I'm thinking you'd have a nice fuel fog.
But on a 750 main body I think it may hurt flow a bit but have a very good signal on those boosters

BLP claims 1000cfm flow on 750 body so I’m not too worried about flow. I always prefer annular, I got my 1 annular double pumper about 10 years ago and everything I had was this way since. Better fuel atomization.
I was also looking at QuickFuel 750 annular carbs to tweak them to run on tunnel ram but it’s not the cheapest option…

98B320C2-8392-4333-9D0F-14C3CEDE2EC2.jpeg


523B4E9F-6E37-4C97-8700-25B6A0D2CAF5.jpeg
 

MOPARMAGA

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BLP claims 1000cfm flow on 750 body so I’m not too worried about flow. I always prefer annular, I got my 1 annular double pumper about 10 years ago and everything I had was this way since. Better fuel atomization.
I was also looking at QuickFuel 750 annular carbs to tweak them to run on tunnel ram but it’s not the cheapest option…

View attachment 1715975580

View attachment 1715975581
Yeah, that's not a bad carb either. The couple I've seen were really close out of the box, the annular would have been better though for both engine.
I would go for it.
 

rumblefish360

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Here is my old 470. 2/10s faster with it over a M1 and a 1050 dominator. Standard port Stage 6 heads which flowed around 320 and 240. Best run was 10.1 with T ram. 9.03 with nos. Kim
M1 single plane?
B block correct?
Who’s Tunnel Ram?
RB Tunnel Ram?
Tell me (us) about the twin carbs.

Thanks Kim.
 

oldkimmer

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Yes M1 single. 440 size. 400 B block. Weiand T ram RB size. 660 Center squirters with metering plates on the rear also. My 470 used a RB intake because I had Stage 6 Mopar heads on it. Kim
 

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BLP claims 1000cfm flow on 750 body so I’m not too worried about flow. I always prefer annular, I got my 1 annular double pumper about 10 years ago and everything I had was this way since. Better fuel atomization.
I was also looking at QuickFuel 750 annular carbs to tweak them to run on tunnel ram but it’s not the cheapest option…

View attachment 1715975580

View attachment 1715975581


You can make these work if you can get them cheaper. You just need to measure EVERYTHING a and then adjust it accordingly.

Those will work just fine.
 

Miszny

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I’m thinking APD could be interesting, good price for full billet carb and they say they tune for you. Also there is tunnel ram option when you try to do online purchase. I sent them some questions…

868F76C7-A569-49DB-AA71-7339029F14ED.jpeg
 

Cheapsunglasses

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It’s my understanding, and I’m by no means anything close to an expert. When you are running multiple carbs, they aren’t individual carbs, they have to act as 1 carb. And there’s also a reduction in cfm, it’s not a full 1500cfm (there’s some science I don’t understand there.) That’s why the idle circuit has to be reduced by half, and I believe there’s other circuitry that has to be reduced too.
 

Rat Bastid

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It’s my understanding, and I’m by no means anything close to an expert. When you are running multiple carbs, they aren’t individual carbs, they have to act as 1 carb. And there’s also a reduction in cfm, it’s not a full 1500cfm (there’s some science I don’t understand there.) That’s why the idle circuit has to be reduced by half, and I believe there’s other circuitry that has to be reduced too.


You can’t reduce the idle circuit by half on anything I know of.
 

MOPARMAGA

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Must've been an uncle tony video, I recall him talking about the cfm thing with dual carbs.
 

Miszny

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As long as you can get it with an annular booster that has at least 16 holes in it.
I asked them this question. I will get main body with no boosters if I have no choice and retrofit annular booster banjos.
 

rumblefish360

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It’s my understanding, and I’m by no means anything close to an expert. When you are running multiple carbs, they aren’t individual carbs, they have to act as 1 carb. And there’s also a reduction in cfm, it’s not a full 1500cfm (there’s some science I don’t understand there.) That’s why the idle circuit has to be reduced by half, and I believe there’s other circuitry that has to be reduced too.
What I think this is about is, if you put two 1500 cfm carbs, they won’t work to there full capacity as if there was only one. This is a reduction in how much is pulled through the carb. Not the capacity of the carb being reduced or the efficiency. The engine likes the extra available air and fuel flow of the twin carbs over just the single carb. The twin carbs make the engine more power with what’s available in overall A&F flow and lack of restriction.

I have no idea about the “Half the idle circuit” needs to be done thing.
 

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The dyno is a good tool for seeing what happens as you over carb an engine or use a carb not sorted for it's intended purpose.
 
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