Hey guys been a while since i have posted,
But its winter hear now and Iam starting to re do my RZ350, The question i want to know is, do you think it would be hard to get 20 extra Hp out of my RZ, I plane on getting pipes,head planned,bored out .0050, and port and polish and a few more odds and ends... let me knwo what you guys think would be the best way to get 20hp and ifs its even possable......... thanks
seann

 

How far are you shaving the head? For real good peformance gains try and get them rechambered and not just shaved, you'll ge a better increase. I wouldn't try and raise it to much, you gotta watch out about spark knock. I would image you wouldn't want to go any furthur then .040" over stock with out getting into detonation issues.

Pipes are going to make it that thing sound awsome. Somthin about power valved 2 strokes[img]i/expressions/face-icon-small-happy.gif[/img]
As far as the top end is conserned, you'll gain a couple of cc's but the real power is made when you open up the intake and transfers and get the intake charge into the crankcase as fast as possiable, larger carbs would also help if you can get them dialed in right.

 

I think the 3 most things that are gonna give me the most power is Pipes,BIGGER carbs, and Port work out my a**hole haha
and other odds and ends from there, reeds reed spacers and such....

 

Pipes, head mod, and porting should give you want you want. The RZ powervalves already give you around 5mm exhaust raise at full opening, but it needs intake and transfer work as well. Dont bore the cylinders any farther than you have to in order to clean them up. You waste good cylinders not to mention reduce the amount of transfer volume available in relation to cylinder size.

 

Hey thanks alot,
So if i was taking my cylenders to a place to get them done, what would i tell them i wanted done
my intake and trsfer ports bigger or wehat?? thansk

 

If you take them to someone that know's what their doing then they will know what to do. If they are unsure or cant give you straight answers and tell you exactly what they will do then dont let them hack on your jugs. If it were me I would spend a little more money and send them to someone who definitely does good work. The RZ jugs cost too much to replace and are getting hard to find.

 

Mojavekid,

Good topic, I just bought a RZ350 motor this week and have spent considerable amount of time researching the topic. From what I read there is about 5 hp difference between the RZ motor and the banshee motor. With that said, people who have done the conversion swear buy it and say there is alot of differnce in the power spread of the RZ compared to the banshee motor.

For pipes I learned only Rocket or PT will clear the powervalves unless you want to dent another set.

My plan is to have the crank true, cylinders ported (MX by Patriot racing), head cut, v-force reads, 28 FS carbs. I surrently have this set up with FMF pipes on my 89 shee, and it works awesome. Bike comes on early, rips your arms off when the powerband hits, has great low end, trailability and good top end. I am sure this set up with an RZ motor will be incredible.

There are several good porters out there and it kind of depends on if you want someone local or not to do the work. If you are going to port send to someone who knows what the hell they are doing. It may cost a bit more but is well worth. You will need to tell them your type of riding, the octane you plan on using and what other complimentary items you will be adding. They will port accordingly.


TO LEARN ALOT ON THIS TOPIC GO TO BANSHEEHQ.COM. These guys know there stuff.

Chris

 

Seann I was talking to bill and he said he dosn't do any porting, nor does he want to start.
Not any mechanic can port. You have to know specific angles, timing, blowdown times, and all that other crap. Your not going to find anyone around here that will do anything for you.

As for the carbs, those 34's are going to be WAY to big on that motor. You'd be better of with a 30. (bill agrees)
You see air flows faster through a smaller opening. If you put on that large of a carb without giving the engine enough "suck" then you will actually be hurting peformance, not gaining. Anyone who knows anything about engines will tell you that. In order to put on that big of a carb you will need to have extensive port work done, or a larger bore.

 

You can't just make them bigger and hope for the best. Your ports are like vavles for a 2 stroke. If you open them to big then you can get into timing issues. Your intake and exaust ports are set-up to be ring friendly. If they are opened up to much then your rings will catch the ports causing major problems. Everything needs to be considered when doing port work. In order to have it done right it's not as easy as just hacking it up and making it bigger.

 

Shavo, I have to disagree with the 34 carbs on the RZ. Most anyone with a mild tuned Banshee motor runs the PJ 34 carbs. I run the 35.5 PWKs on my bike with no loss of bottom end. The powervalved system should give even better bottom and midrange power. If he wants the most bottom and midrange he can get then a 28 or 30 flatside would be good, but I am never against 34's on banshee motors that are over stock.