Holley 750 double pumper jetting

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Basin_Runner355
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Holley 750 double pumper jetting

Postby Basin_Runner355 » Thu Dec 14, 2017 5:36 am

I bought a used Holley 750 double pumper it’s been sitting on a a shelf for a while so I’m going to put a rebuild kit in it so I know it’s fresh was wondering if somebody could tell me what jets should be in it it’s going on a bone stock zz4 with a 2:1 belt reduction he said don’t remember what motor it came off off cause he has like 20 Work boats so while it’s apart I wanna check make sure I have the right jets in it so I don’t have to tear it down again
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

swamper2
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Re: Holley 750 double pumper jetting

Postby swamper2 » Fri Dec 15, 2017 8:19 am

http://www.innovatemotorsports.com/prod ... l_plus.php

To do it right spend a few bucks and buy one of these and take the guess work out . In the long run it will save you time and money plus a peace of mind
16ft alumitech/406sbc/2.38w/3-80in.R's

ladyblackwater
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Re: Holley 750 double pumper jetting

Postby ladyblackwater » Fri Dec 15, 2017 11:12 am

Swamper 2 is correct. The innovate gauge is great and will give you the best tuning ability. Every motor will use different jetting even if it's the same cubic inch motor. There is no one size fits all. I have 2 innovate gauges that I'm not using anymore since I've gone to EFI. I'll be happy to sell 1 our both if you are interested.
Greater love hath no man, than to lay his life down for a friend.

Bitterly clinging to my guns and my religion!

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Basin_Runner355
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Location: St.martinville , Louisiana

Re: Holley 750 double pumper jetting

Postby Basin_Runner355 » Sun Dec 17, 2017 7:57 pm

How it works you have to put a fitting on your headers or in the flex pipe
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

jeepinocala1111
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Re: Holley 750 double pumper jetting

Postby jeepinocala1111 » Sun Dec 17, 2017 8:39 pm

Basin_Runner355 wrote:How it works you have to put a fitting on your headers or in the flex pipe


I run the double one on each side it works great you can be sure everything it running correctly I welded the bungs just before the mufflers on the muffler inlet flange. I like it but know many people who do not use them and do just fine.

Basin_Runner355
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Posts: 134
Joined: Sun Nov 13, 2016 7:16 am
Location: St.martinville , Louisiana

Re: Holley 750 double pumper jetting

Postby Basin_Runner355 » Mon Dec 18, 2017 6:03 am

Well my mechanic don’t really work on small boats and he has some made for 3.5 and 4 inch pipe that he hooks on the ends and tunes it off his computer but he don’t have any made for 3 inch yet
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

Basin_Runner355
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Joined: Sun Nov 13, 2016 7:16 am
Location: St.martinville , Louisiana

Re: Holley 750 double pumper jetting

Postby Basin_Runner355 » Mon Dec 18, 2017 6:05 am

And all I have is headers and the flux pipe goes straight out the back no mufflers
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

swamper2
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Location: harsens island michigan

Re: Holley 750 double pumper jetting

Postby swamper2 » Mon Dec 18, 2017 7:25 am

you have to weld the bungs on the end of the headers before the flex pipe. the flex pipe leaks oxygen and will give you false readings. Read the install manual in the Innovate web site I sent you
16ft alumitech/406sbc/2.38w/3-80in.R's

ladyblackwater
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Re: Holley 750 double pumper jetting

Postby ladyblackwater » Mon Dec 18, 2017 10:08 pm

You would weld the bung right on the collector of the header.
Greater love hath no man, than to lay his life down for a friend.

Bitterly clinging to my guns and my religion!

I am that conservative republican your momma warned you about!

swamper2
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Location: harsens island michigan

Re: Holley 750 double pumper jetting

Postby swamper2 » Sun Dec 24, 2017 9:41 am

16ft alumitech/406sbc/2.38w/3-80in.R's

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JAMES
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Re: Holley 750 double pumper jetting

Postby JAMES » Mon Jan 01, 2018 8:08 pm

Save your money on that gauge send the carburetor to a specialist S&S carburetor is in my opinion is one of the best send it to
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ladyblackwater
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Re: Holley 750 double pumper jetting

Postby ladyblackwater » Mon Jan 01, 2018 11:13 pm

James there is no carb guy that can get it as close as an AFR gauge can get it. The only way it could be pretty much perfect is by dynoing the motor with prop and all. It's not hard to tune a carb yourself if you know the basics and have an AFR gauge.
Greater love hath no man, than to lay his life down for a friend.

Bitterly clinging to my guns and my religion!

I am that conservative republican your momma warned you about!


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