extractors/exhaust system

MightyBoy tech questions and answers.
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jono
Posts: 453
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Location: Hobart, Tassie

hey guys,

just wondering, i got a qoute for extractors the other day. two different ones. 400 odd for extractors done on the press and 500 od for ones with mandrel bends. also, he said he was going to get a completely new exhaust header/gaskets and build the extractors off that or something.
is it necessary to get that new stuff??

getting a system put in on wedensay, minus the extractors (cant afford them yet :( ... he thought 2 inch would be good, but i've heard that 1.75"is the biggest u should go. i've got stock F8B with a weber going on in a few weeks......

anyway, any thoughts??

thanks,

jono
Speed Limited: I'm Pedalling as Fast as I Can
1987 Mighty Boy
Injected F8B (love it!)

http://www.freewebs.com/fitre/
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Brayden
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You're correct about the size, 1.75" is the largest you should go.

If you want to save $100 on the extractors then get them press bent, chances are that mandrels won't make much difference anyway. ;)
F8B EFI turbo - Three pots and a snail.
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jono
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Location: Hobart, Tassie

Hey Brayden, what size do you think I should go in the extractors with this manifold?? Plus there is possibility of a supercharger in the future. 2inch perhaps?
Speed Limited: I'm Pedalling as Fast as I Can
1987 Mighty Boy
Injected F8B (love it!)

http://www.freewebs.com/fitre/
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Brayden
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1¼" runners, 2"ish collector into a 1¾" system.
F8B EFI turbo - Three pots and a snail.
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jono
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okay, i will tell the exhaust dudes that. aslready have a 1.75 inch system.. hopefully will make a bit of difference... :roll:

thanks mate 8)
Speed Limited: I'm Pedalling as Fast as I Can
1987 Mighty Boy
Injected F8B (love it!)

http://www.freewebs.com/fitre/
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Brayden
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Seat of the pants you'll notice a difference in mid to high range performance, but the real power comes with mods to the intake side. (Carby, more air/fuel.)
F8B EFI turbo - Three pots and a snail.
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jono
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Yeah, well I was hoping extractors should help my engine out a bit with this EFI manifold, needs to breathe a bit better.
Speed Limited: I'm Pedalling as Fast as I Can
1987 Mighty Boy
Injected F8B (love it!)

http://www.freewebs.com/fitre/
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me217
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sorry to steal the thread but i just got a quick question.
would 2" all the way through no tip on the end. be alright for supercharged f8b. and a standard f5a (as a mate is thinking of a new exhaust.).


me217
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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jono
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Location: Hobart, Tassie

2 inch too big, esp for F5A... i have 1.75 inch, and that should be fine for s supercharged setup
Speed Limited: I'm Pedalling as Fast as I Can
1987 Mighty Boy
Injected F8B (love it!)

http://www.freewebs.com/fitre/
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me217
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what damage can be caused by runnin 2". or is there just a lose of power.

me217
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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Jermaine
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loss of power
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me217
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ok thanks.


me217
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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Brayden
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Back to the original topic:

Jono, I had a mental blank and forgot you have EFI. In that case all you'd probably need is a bigger TB and some tweaks to the fueling. :)
F8B EFI turbo - Three pots and a snail.
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jono
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LOL, that's okay, though you must have forgotten! :)

so those sizes for extractors will still be good then?
Speed Limited: I'm Pedalling as Fast as I Can
1987 Mighty Boy
Injected F8B (love it!)

http://www.freewebs.com/fitre/
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Jermaine
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hey im interested in extractors...
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