dyno time!!

sideshowBob said:
Is that 24cc with the head installed? You loose about 4 cc with the head installed which would be @ 20cc that works out to approx 12.6 : 1.

That exhaust port height[30mm] is pretty typical for a porting spec on these engines gives you approx 198 degrees exhaust duration.

You will need to provide a squish measurement, squish band width, + squish band angle as well for the "Gurus" to help you out. There is a lot of science in the head specs.

Again I must state the HP numbers you dynoed at were very respectable for a stock piped trail 700.

JM.02c

Bob

that volume is correct i did it installed and got 20cc and in the vice i got 24cc. my squish is 0.05-0.052. the width of my squish band is 7.6mm. the squish angle is about 11-12 degrees. i am still surprised that it made 148 at 8500.
 

JM.02c

All your specs you are providing sound pretty good[to me] for a trail ported engine...the numbers don't suprise me at all as... IMO...the stock pipes are awesome for stock RPMs but if you want to make big power out of these you have to spin em! Remember HP = torque x RPM divided by 5252.

I have yet to see a typical trail ported 700 tripple make torque much above 92 ft lbs

So:

92 x 8500 RPM
-------------- = 148.8 hp....its that simple
5252

Now if you could make that same torque at 9200 RPM with after market pipes

92 x 9200
--------- = 161.2 hp....now you're talking!
5252

Bob
 
what are the choices for aftermarket pipes that run at 9200? i was told haucks run at 98-10200rpms.
 
madzx2 said:
what are the choices for aftermarket pipes that run at 9200? i was told haucks run at 98-10200rpms.

You may be able to get a bit more HP with the stock pipes and bigger carbs and some head work.

I am long done with building mod sleds but if I was still enthusiastic enough to tackle it I would attempt to adapt a set of Viper Bender, SLP, or Simmons CPR pipes to the SRX...other then that you may have to get a set built if you want to run 9200 and you will also need a different CDI.

Check this link out for what some pipes can do for a Viper.

http://www.m-performance.com/Sidor/dyno_yamaha.htm


The Viper engine is similar to a very mildly ported SRX and even spinning it at higher RPMs does not produce much more hp then you are already getting at 8500...it shows how good the stock pipes really are, thats probably why very few aftermarket pipes were avail for the SRX.

Bob
 
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i just wish i had a definite answer as to what i have. im not positive what rpms i should be running. i am fine with running 8500 next season but if my cylinders are done for more ill run it that way.
 
Some of the members have used the Mach Z carbs, some Polaris XCR carbs...a search will get you lots of info...Valin for one has experience with these and would be a good one to ask about these as you want to get the proper ones.
I always used individual TMX 38s on my sleds but they are a little more involved to install as they are not racked and have a tripple throttle cable.
 
madzx2 said:
i just wish i had a definite answer as to what i have. im not positive what rpms i should be running. i am fine with running 8500 next season but if my cylinders are done for more ill run it that way.

the only accurate way to know what you have there is to degree it out and then bring it up to better specs if it needs it.
 


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