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-   -   8-71 Low Profile Supercharger/manifold/spark Arrestor (https://www.offshoreonly.com/forums/general-q/179145-8-71-low-profile-supercharger-manifold-spark-arrestor.html)

JRider 02-05-2008 07:06 PM

8-71 Low Profile Supercharger/manifold/spark Arrestor
 
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I have a 575sci in a 28' Profile cat. I would really like to relieve the 256 of its duty and up it to a 8-71. I am very limited in hatch space...anyone know of a low profile blower manifold or what company has the lowest measured height?

Could the blower or manifold be milled down some? I saw Foose do it to one of his cars...

Any ideas on a low profile spark arrestor or what can be done to lower the stocker?

I am looking to retain the stock dual throttle body setup and avoid cutting the stock hatch if at all possible. My boat/hatch is identical to the pic below and the hatch is a good looking piece in my opinion.

Thanks,
JRider

CPPerformance 02-05-2008 07:47 PM


Originally Posted by JRider (Post 2434390)
I have a 575sci in a 28' Profile cat. I would really like to relieve the 256 of its duty and up it to a 8-71. I am very limited in hatch space...anyone know of a low profile blower manifold or what company has the lowest measured height?

Could the blower or manifold be milled down some? I saw Foose do it to one of his cars...

Any ideas on a low profile spark arrestor or what can be done to lower the stocker?

I am looking to retain the stock dual throttle body setup and avoid cutting the stock hatch if at all possible. My boat/hatch is identical to the pic below and the hatch is a good looking piece in my opinion.

Thanks,
JRider


The Blower Shop's intake is 4.40" overall. In the case that you mill the manifold any lower you may end up with valve cover clearance issue's just food for thought.

The overall height of a TBS 8-71 is 12.98" most 250 style superchargers are about 10.50 inches. There's roughly 2-1/2" difference.

As for a flame arrestor Hardin Marine offers a unit with a 2" elemant but the overall is about 2-3/4" due to the flame arrestors bases which are needed to clear the linkage.

Question who is going to tune the EFI once you make this change as the 575 on it's own is extremely sensitive to tuning adjustments ?

Hope this helps

JRider 02-05-2008 09:36 PM

Thanks for the input. I live in central Michigan not even 2 hours from Tyler Crocket. He will be my first choice as he can tune it right in the boat and he also has experience with the 575.

Looking at Weiands dimension chart the 256 is exactly 10.5",the 8-71 is 12.125". I may have to go with the Weiand if I cant figure anything else out.

Bottomfeeder 02-05-2008 09:43 PM

How about a whipple? Nice and low even intercooled,,,

EWB 02-05-2008 10:16 PM

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I have added a 8-71 to the 575 and it turned out well.

JRider 02-05-2008 11:11 PM


Originally Posted by Bottomfeeder (Post 2434650)
How about a whipple? Nice and low even intercooled,,,

I would like to use a whipple but cost is a huge factor and I am not sure if there is a good way to use the stock fuel injection with a whipple.

The 8-71 will be much more efficient than the 256...so much that I will not need an intercooler...I cannot fit one anyway.

JRider 02-05-2008 11:16 PM

EWB...you must be the guy Steve Zuckerman told me about. Did you have many issues adapting linkages + piping? Very good looking setup you have there!

jeff1000man 02-06-2008 09:16 PM

Put some carburators on it and sell off that EFI stuff. Just my .02

Croozin2 02-07-2008 07:25 AM


Originally Posted by jeff1000man (Post 2436123)
Put some carburators on it and sell off that EFI stuff. Just my .02

I'll trade you some carbs for "that EFI stuff.":D

JRider 02-07-2008 10:58 AM

Carbs did cross my mind but they would not solve my clearance issue. It may not be the best EFI system but cold starts are great and has had great manners in any temp or humidity. The advantage carbs have is that they are tunable by the average guy.


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