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"It's HONDO, honey"
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Real men have two :D. The more air and gas you can get into a motor the more horsepower it makes, but more importantly if your running a big cubic inch motor sometimes a single carb on a tunnel ram is not enough fuel feed. A tunnel ram builds momentium with a lot of gas and air. Go for the two :)devil
 

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No single tr's for me.....except the one that cost me 6k because I burnt a hole through a set of 990's between 5 and 7 bid enougph to stick your pinky finger through.
 

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Is there a reason why i don't see too many single tunnel rams on jet boats these days ?
Do hi-rise manifolds flow better than a single ?.........tell me your thoughts and experiences.
I ran a single top years ago and learned alot about what it takes to make them run. If you figure the plenum area vs the feul than you will see that when you hit the load peddle it's going to want a big shot of feul. Then you figure that air mass at rpm and it will or should tell you that the motor is going to need an equal amount of feul at all rpm ranges to perform at potential. Fats where it's at with a single top. M
 

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I've always heard that it leans out a couple of the cylinders, thus causing holes in the tops of pistons!

No way would I go that route.
 

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....like warm apple pie
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I ran that setup for about 4-5 years and what I learned (thanks Greg Shoemaker) is that its tough to dial in a motor with that. With that kind of volume in the manifold, you stab it and start hauling ass, the mixture wants to head towards the rear cylinders, and in return, leaning out the front cylinders. Mine was ALWAYS a bitch to start cold too. Once the vacuum was built after the first fire, it would kick immediately, all weekend long....it was just on the ramp trying to get fuel to all cylinders, not just the center 4. I was advised by many people to either go dual carbs or get rid of the tunnel ram. I was getting ready to dump the manifold for a Performer RPM and ended up selling the boat instead.

Just my experience. Good luck with the project! :D
 

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Resident Ford Nut
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10,075 Posts
Try this:
http://www.performanceboats.com//showthread.php?t=446

The biggest problem is distribution. Modern Hi-Rise intakes will do a much better job

Edit: at the bottom of the thread idex page the default setting for thread's is set at 2 months. Change it to 1 year and you will see many more pages of past thread's.


Sleeper CP
Big Inch Ford Lover :D
 

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jetboataholic
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What about a Team-G, are those also good Jet Boat manifolds?

Thanks.
 

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A Team G is a great manifold for a jet.

I have never had a problem with a single tunnel ram. If they were that bad of a design the big company's would not have made so many. Nothing wrong with a correctly set single T-ram.
 

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Resident Ford Nut
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10,075 Posts
A Team G is a great manifold for a jet.

I have never had a problem with a single tunnel ram. If they were that bad of a design the big company's would not have made so many. Nothing wrong with a correctly set single T-ram.

Why did Vega, Pinto and Pacer come to mind when I read that ?

Sleeper CP :D
 

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I think the design of the T-ram has alot to do with it. I have an Offy single 4 ram on my 460 and have no problems (other than the hard to start cold thing). It shows good fuel distribution when checking the plugs (no lean cylinders) , and no I dont baby it :p
 

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