Hi
I think I read somewhere here that you had ported a single pipe npv motor? A 700. Did you ever put that motor on the dyno? If so, it would be interresting to see the results. Where were the gains on the powerband, peak power etc.
A dealer told me a long time ago that if you port you're just moving the power from one part of the powerband to another. Is this true, if so, where might the npv 700 lose its power and where does it gain it?
How large jets would one be using on a ported npv motor?
I think I read somewhere here that you had ported a single pipe npv motor? A 700. Did you ever put that motor on the dyno? If so, it would be interresting to see the results. Where were the gains on the powerband, peak power etc.
A dealer told me a long time ago that if you port you're just moving the power from one part of the powerband to another. Is this true, if so, where might the npv 700 lose its power and where does it gain it?
How large jets would one be using on a ported npv motor?
MountainRx1
New member
From what I heard, there aren't really any gains on porting a red headed triple, unless you pipe it too....
there is a wicked single pipe redhead 700 motor running around here that runs with 700 srx's from what i hear. be nice to see it run on radar and see if it is true.
MountainRx1 said:
That is a completly False STATEMENT.
Don has did many of those engine's.Don't think he ever dynoed one.He did one for me and it took out many srx's,f7's and other big bore sleds.They are a little rocket with the the right guy doing the engine.
pro116 said:
Who is Don? Is that Mrviper700?
yes MrViper700
Triple X
New member
Somewhere around 12hp from porting alone!
How reliable are the engines if porting is done? I prefer to keep stock sound and reliability but would like a little more power. I have had hopped up motors in the past and was always working on, I like to ride around 150 to 200 miles day, last year 2,450 miles.
yamyrider
Active member
trail porting is very reliable and works well with a few other mods like head gasket, reed cage mod and clutching.
yamyrider said:
yes if motors are done right the are no less reliable then stock.
mopar1rules
Active member
right, ports need to be chamfered properly and the shape of the ports, especially the exhaust port, determine ring life. a rectangular wide exhaust port, would contribute to lower ring life vs a oval shaped exhaust port. the oval shape, eases the ring in and out of the ring land, everytime the piston travels up and down past the exhaust port. the rectangular shape is too harsh on rings. so, if you have a conservative trail port job, w/port shapes that help keep ring life, and ports are chamfered properly, your engine will still remain reliable.
those non power valve engine went they are ported they will loose low power end ..cause the higher u raised the exhaust port the higher duration it will have ..so thats the beneefits of a power valve engine ... u can increase the duration of the cylinder(some) and not loosing low end ..this is the idea about power valve ...but u need to know what your doing went its time to ported
I have milled the head .020 only. I do this instead of separating the head gaskets.