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Discussion Starter #1
im talking Exhaust tuning.

Header tube sizing length. collector sizing length?

has anyone played with this much?

has anyone tried Step tube sizing.


thanks Travis
 

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im talking Exhaust tuning.

Header tube sizing length. collector sizing length?

has anyone played with this much?

has anyone tried Step tube sizing.


thanks Travis
Funny,you posted this..I was talking to Joel at Rewarder yesterday about putting Merge Collecters on mine
Ive got a friend with Steped tubes on his Lemmons Hedders..but the boat hasnt seen the water yet
 

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Discussion Starter #3
no really even talks about much?

seems they buy some headers and call it good.

when do the normal size header tubes that come on Rewarders or Bassets start to become restrictive?

are twisties worse than regular ones?
 

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Headers are worth a ton of HP

Great meeting you this past weekend
 

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Discussion Starter #5
Headers are worth a ton of HP

Great meeting you this past weekend
same goes for you Info!

okay so ill bite

my 565 900 plus HP what headers would give the best results??

it is extremely Important with my other hobby Harleys.

i understand were are talking about 8 cylinders and not 2 but imo this is a important part of the process if you are looking for everything in your build.

Travis
 

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I remember Josh tellin me that he ran the big tube headers like Mailman runs and it killed his engine .. I've been told that the rewarder upsweeps i'm running on my race boat is hurting me alittle but have yet to do back to back testing .. I wanted to take my twisties to the last race and put them on and make a pass, just haven't done it .. I was talkin with some guys that run the Stainless headers and some of them have different length collectors to tune the boat with .. I'm sure it all makes a difference, not sure you would feel it at the lake but on the clocks at the track you would see it on the time slip ..
 

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The more power you make and the higher the rpm you run, the more effect a tuned ex will have. Travis, you should be running a 2.25 to 2.375 step w/4" collector to get the most from your deal. Primary lengths, collector diameter, collector length and type, etc all play a role. If you want to play at the top, you better be up on the latest ex. tuning. :thumb:
 

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Discussion Starter #8
The more power you make and the higher the rpm you run, the more effect a tuned ex will have. Travis, you should be running a 2.25 to 2.375 step w/4" collector to get the most from your deal. Primary lengths, collector diameter, collector length and type, etc all play a role. If you want to play at the top, you better be up on the latest ex. tuning. :thumb:
well this is what im talking about!

who would make me something like this?
 

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Discussion Starter #9
I remember Josh tellin me that he ran the big tube headers like Mailman runs and it killed his engine .. I've been told that the rewarder upsweeps i'm running on my race boat is hurting me alittle but have yet to do back to back testing .. I wanted to take my twisties to the last race and put them on and make a pass, just haven't done it .. I was talkin with some guys that run the Stainless headers and some of them have different length collectors to tune the boat with .. I'm sure it all makes a difference, not sure you would feel it at the lake but on the clocks at the track you would see it on the time slip ..

Tiger had some SS headers on his boat then switched to some Blower stlye bigger tubes and collector and pick up RPM. this was on 565 RM motor.
 

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same goes for you Info!

okay so ill bite

my 565 900 plus HP what headers would give the best results??

it is extremely Important with my other hobby Harleys.

i understand were are talking about 8 cylinders and not 2 but imo this is a important part of the process if you are looking for everything in your build.

Travis

We have found that the Basset Jet Boat Style Headers are about the best bang for the buck(Not Twistys). 2.25 Primary, 4.0 Collectors cut 12-13" long. I realize this is a generic statement but from here things will get more expensive.
 

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well this is what im talking about!

who would make me something like this?
Not sure about your area but you could contact someone like Lemons or maybe Jim @ Rewarder in CA. Lots of guys running custom headers...just ask around. :))THumbsUp
 

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Discussion Starter #13
Not sure about your area but you could contact someone like Lemons or maybe Jim @ Rewarder in CA. Lots of guys running custom headers...just ask around. :))THumbsUp

i think i will give lemons a call as i really like his style headers.
 

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I am guessing your question is directed towards maximum performance and not something that looks good and is loud. If so, there is no such thing as a one size fits all solution. In an non super or turbocharged engine, headers are a part of the intake and exhaust system and what you do on one end affects the other. If you are speaking about tuned headers, they offer maximum performance over a given RPM range. It also makes a difference if you are running dry or wet exhaust. If you think each time the exhaust valve opens a "pill" of exhaust is discharged into the primary tube. You want to achieve maximum velocity of the pill with minimal resistance (backpressure) as the pill moves down the primary. When the pill leaves the primary tube and enters the collector it generates a small vacuum in the primary tube. In an ideal world the vacuum occurs when the intake opens and not only are the burnt gasses pulled out of the cylinder but a larger volume of the intake charge is pulled into the cylinder. This is called scavenging. There is such a thing as having too much scavening. Decreasing collector diameter and or increasing lenght of the collector moves the maximum power lower in the RPM range and ususally increases torque. Back when I was involved in drag racing, we would take multiple collector extensions of different lengths and tune the car to the track and weather conditions for the given day. On 1/8 mile track we could see up to .2 to .3 seconds improvement from least beneficial to most beneficial combination. There are computer programs that will detail optimum primary size and length along with collector for a given engine combination. Pretty sure a good custom header shop can do this if you are able to provide the specifics of your engine and Rpm you want to generate the most power in.

Good luck, and bring plenty of money.
 

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Discussion Starter #16

so is this software to simulate exhaust building-tuning?

sorry i opened it up and it wants me to pay money,lol!!!


oh to the other feller if i was worried about money i would get out of this kinda boating and ride around in my 16 foot flat bottom with my 5hp merc
 

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Discussion Starter #17
wasn't there guys on here that some nice build SS exhaust built by Lucas fab(if thats right)?


what i wanna try to understand is how many steps(in Primary tubes) and what length is beneficial or not at all?

collector sizing and length can be played with later if built with slip on collectors

thanks for the responses so far.

Travis
 

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Discussion Starter #19
Oh, I'm sorry, I thought you were serious about this;)
i appreciate the link and will be downloading.

oh im serious just asking question and hoping to learn something along the way but i guess not many even worry about this step?

hell just put some zommies b/c they are loud and cool or off the shelf headers will be fine for your lake boat,ect ect.

i have a shitload of money in my 565 and want things to work together and i have all winter to improve the exhaust side of things.

maybe im being a freak and wasting money for no real gain? it seems to be what i do best :wink2:
 

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Just put the goddam headers on there and run the mother focker !!!!!
 
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