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Headers/exhaust Advice For Vfr-750 (95')


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#1 grasshopperman71

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Posted 18 September 2013 - 08:03 PM

Hi gang,

Im new here and have just started building a VFR-750 Custom - Im looking for some advice or feedback on my system.
...
The exhaust will be the main power advantage Im looking for at this stage (plus some weight reduction as well)..
Maybe once Ive finished the style of the bike, I will look for more grunt.  
...
Questions. 
1/ Are stock headers the go - or can someone give me any advice on headers that may give me some more HP ? There doesnt seem to be much around in the header department. 

2 / My plan is to have the exhaust exiting under the seat so I can fully expose the swingarm. (will be building a complete new rear subframe and re-designing the rear-end completely)

Any feedback or links to someone who has done this mod would be helpful. 

Thanks in advance, appreciate any tips. 
J. 



#2 Veefer800Canuck

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Posted 19 September 2013 - 12:12 AM

Not much on offer for your bike besides Delkevic, Motad and Sandy Bike Spares.

 

The SBS system has some hack merges in them, I'd avoid them.

 

The exhausts available for your bike are generally regarded as stock replacements, although in Stainless Steel, so that part is a plus.

 

You're not going to gain a bunch of power from any of them. Maybe 3-5 hp from a slipon muffler, but that's probably optimistic.



#3 mk2davis

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Posted 19 September 2013 - 12:47 AM

Darn near everyone here knows more than I do, but let's start with your performance goals.  Are you looking to hit specific numbers?  I'd be surprised if you gained 5 on dyno purely through exhaust.

 

I also don't know about the 4G, but on the 3G, space does get tight when it comes to an under tail exhaust.  A left exit may be worth considering.



#4 NakedViffer

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Posted 19 September 2013 - 12:59 AM

Exhaust options are just plain tough for our bikes, the only decent performance options are big money. Some time in the future I plan on buying a 1998 header from a 5g viffer and see if i can't massage it onto my 95. The 98 header is known for being the most performance oriented header on a stock VFR, yet I'm fairly certain it will only "bolt-on" to the 98 and newer 800's.

I have tons of projects on my plate, and the bike already has a long list of to-do's. And my ultimate goal is to turbocharge it so I'm looking at making my own header/turbo manifold anyway, but if i do get around to scooping a 98 header for cheap I'll see what it takes to fit it to the 4g and tro to document it. Now who wants to donate a header to the cause?



#5 grasshopperman71

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Posted 19 September 2013 - 01:24 AM

Thanks very much guys!

Ive seen a couple of dudes do under-seat exits , and this is probably where Im headed. (no pun intended). 
I dont think the shorts stumpy pipes offer enough back-pressure and Im not keen on compromising performance for sound or looks.
 
Im not looking for anything super'loud ... lets face it,  the motor is the sweetest sound ever to come from a motorcycle...
...
A mate has offered to donate a Jardine carbon system with a dual pipe look.

Naked Viffer > yeah, Im already thinking ahead to Turbo or Supercharging down the track, so to speak.  
PS , nice Bike. I might take a closer look at it. 

Thanks again. 
 



#6 NakedViffer

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Posted 19 September 2013 - 01:49 AM

Yeah, i have a serious feeling these motor will just LOVE boost, its just a matter of getting around the space constraints. I'm honestly thinking two tiny turbochargers a bit bigger than a beer can at this point. i'm thinking I could make them fit much easier. I've done some semi-mock up work with a small-ish turbo from a cage MHI TD05-14B, and even though it would do decent with this displacement, theres hardly anywhere to put the damn thing. I think one where the collector is, and one infront of the forward bank would work nice. But then again a custom tail would allow me to place the bigger single under there and still utilize my stock exhaust while just having to put a turbo flange on the mid pipe and bend it into place.

So many ideas, so little time and money.



#7 grasshopperman71

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Posted 19 September 2013 - 01:56 AM

My mate is a master craftsmen and all round genius know-all . Lol . 
He would find a spot for it.. 
.
Would love to hear how it goes for you if you manage to work it all out .. 
.
Ive seen a couple of videos on YT about blokes putting blowers on them as well . 

I just want to get mine looking right first - I dont want it to look like Frankenstein . 



#8 Beck

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Posted 19 September 2013 - 02:57 AM

A highly regarded full exhaust system was made by Two Brothers for the 4th Gen breifly during the 90's. Those are considered by many as the "Grail" exhaust system to get for 4th gens., but they are close to unobtainium these days and cost a mint if you can even find one in good condition. If there might be a good one available new these days, might be the one still being sold by Motad, only because the company had been an established one for so long already and I would think their designs are mostly good because of it....

#9 Dutchy

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Posted 19 September 2013 - 03:26 AM

Your biggest gain will be weight; the OEM muffler alone weighs in a 6.1 kilo.

My CF Akrapovic Hex weighs 1.6 kilo.

 

Member VFROEM here has a set of custom built titanium headers under his 3rd gen.........

 

 

Keep us posted on your progress, we love pictures here! :cool:



#10 grasshopperman71

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Posted 19 September 2013 - 04:45 AM

Thanks Beck & Dutchy ..
..
I am hoping to get the thing up to his workshop in the next 2 weeks.
I've got the rego slip sorted - from here it's the green light to start pulling her down.
.
Appreciate your help guys

Cheers




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