The exhaust to beat the FMF

Message

wistech · #61 Post by **wistech** » Sun Mar 16, 2008 1:36 pm

QUOTE (cobradaler @ Mar 12 2008, 12:24 PM) <{POST_SNAPBACK}>

the longer fmf cans lose hp for some reason, shorten them up and it should gain a little back.

I kind of agree . About a year ago when I made my first left side duals like Mike did the open fmf mufflers performed the same as my custom dual in dual out muffler. It was the same 10 inch core that Mike has. The fmf cores are 14 inches.

wistech · #62 Post by **wistech** » Sun Mar 16, 2008 1:44 pm

QUOTE (Blasterboy11 @ Mar 13 2008, 08:10 AM) <{POST_SNAPBACK}>

Very interesting, when you switched the Toaster for the FMF, was it the FMF head pipe? Cause i know from cars, the headers are where you make or break the powerband in the exhaust. Cool, good work. So does this mean the prices for the Ti system will go down, lol

The dual toasters were switched to a full TI exhaust . I doubt the price of the FMF systems with go down as they are still way better than any other exhaust out there and cheaper than the duals. Here is the secret weapon that can trail ride and race legally while still gaining power . I have noticed that several other pipe makers have gone to the cone shape screen that is very similar to this one. Most like the FMF just use a small one inch pipe in the end of the core with a screen behind it.
It is hard to believe that a screen that fine isnt a huge restriction but the dyno says no.

m_mcgranahan · #63 Post by **m_mcgranahan** » Mon Aug 04, 2008 4:50 am

Hi,

Interesting that the FMF TI actuall makes about 2-3 more HP than the Witech duals till 5k and then it starts to fall off the pace. Intersting to see for MX riding. The dual toasters were up really low, and then dropped off and then made a comeback in the end.

Thanks for all the cool work and dyno results.

God bless...

Mark

wistech · #64 Post by **wistech** » Mon Aug 04, 2008 5:48 am

QUOTE (m_mcgranahan @ Aug 3 2008, 11:50 PM) <{POST_SNAPBACK}>

Hi,

Interesting that the FMF TI actuall makes about 2-3 more HP than the Witech duals till 5k and then it starts to fall off the pace. Intersting to see for MX riding. The dual toasters were up really low, and then dropped off and then made a comeback in the end.

Thanks for all the cool work and dyno results.

God bless...

Mark

You might have been looking at the torque lines which start on the upper left. Where the lines are swapping below 6k is less than a horsey. The torque is a what is down about 2 ft pounds. This engine was built with max high rpm power in mind so it isn't much of an improvemet from stock at all at low revs.
I wouldn't want to mx this one. The 432 we have in Tonie's quad has slightly less agressive timing to focus a little more on midrange as that what its going to be used for.
I wouldn't jump on the stock engine bandwagon as this is kind of a purpose built one off motor just to beat the record. I doubt you will ever see 432's pulling these numbers for a long time if ever. I mean really how many have ever broke 50? I can think of one (Kara's) and I think Tim had one. (Matt)

m_mcgranahan · #65 Post by **m_mcgranahan** » Mon Aug 04, 2008 11:41 am

Hi,

Yeah you are right on the 5k. I was actually looking at the 6k point, but typed the wrong thing. Just curious, what was the cam timing on that motor?
I bet this one is fun in the sand!
THanks

God bless...

Mark

wistech · #66 Post by **wistech** » Mon Mar 09, 2009 3:00 am

The big bore duals beat the fmf handily.

m_mcgranahan · #67 Post by **m_mcgranahan** » Mon Mar 09, 2009 5:04 am

Hi,

SO this chart is using the 1 3/8 exhaust you made and using the dual toasters? Have you ever thought about adding a small "expansion chamber" like the fmf "megabomb" to your design? Once you go duals it seems like they could be added. Any ideas on how they work to add power and quiet the db outptu? Just been mulling this one over for a while.

Thanks

GOd bless...

Mark

QUOTE (Wistech @ Mar 9 2009, 03:00 AM) <{POST_SNAPBACK}>

The big bore duals beat the fmf handily.

wistech · #68 Post by **wistech** » Mon Mar 09, 2009 4:25 pm

This is not the small tube headers from the speed with the dual toasters. . These go huge right off the head and have the head ported to match. Dual FMF open mufflers full length just like the stock fmf had.

Trouble · #69 Post by **Trouble** » Mon Mar 09, 2009 5:00 pm

Anybody ever try a reverse megaphone exhaust on the c dale?being ol'skool i know it appears that true megaphone exhaust make the most power.if you look at dyno shoot outs of various exhaust for like the 400ex or raptor,it was the sparks for the 400ex and the graydon proline for the raptor which both are reverse megaphone design.i have a Tc racing supertrapp that i had on my 385ex that i will adapt for the sake of tuning one day.a silencer is just a aluminum shell with a perforated core,power characteristics may vary slightly by changing the length and core diameter but im convinced the return wave of the megaphone greatly helps with hp,especially in the mid and up.With the c dale being fuel injected it still shouldnt matter,its still a internal combustion engine.

cannondale27 · #70 Post by **cannondale27** » Mon Mar 09, 2009 9:26 pm

Were a few of those made for Cannondales.Ti exhaust beat it but it wasnt on a Ti headpipe.