New head, trying new port technique: High Velocity Intake Porting!

[vile1]

So my GPZ 600 is getting a little old and is in need of a rebuild, etc.

Picked up a new cylinder head and decided it'll be getting a rebuilt head with some porting.

Well, I remembered this guy talking about High velocity porting and looked it up again. It's the same dude that promotes the "Grip it and Rip it" method to breaking engines in (which has been working great for me for a long time) So i read up on his site: www.mototuneusa.com

I'm going to give this a shot. All you need is some JB weld and a porting tool.

I'm 100% going to do this, so I'm not looking for help, but more as a way of finding out what you guys think of this method? (mhaskell should get in here, Im sure he'll have something to say )
It makes complete sense to me and think I'll grab some more power out of this 600.

Pics:

Before (stock)



After (HV ports):

[zoopnazi]

I scrolled through that c. 1996 website and only saw a gif of the pics you posted. No actual information of what the hell you are going to do. Care to explain?

[vile1]

Originally Posted by zoopnazi

I scrolled through that c. 1996 website and only saw a gif of the pics you posted. No actual information of what the hell you are going to do. Care to explain?

Yeah, the site is a little weird. It's layout makes you think he's gonna start charging you shit, or its gonna be a hooker palace or some shit. But its a guy that truly wants to help out the sport of motorcycling.

The format is like a newsletter. You sign up by entering an email address (any fake email like asdads@sdfsdf.com will work, he just wants you to spread the word). But the second you enter the email you get to a page with links to all the newsletters. His shit is really insightful, but if you click on newsletter 16-20 you get a full pictoral How-To guide on the porting.


Basically, he states that stock ports are already too big and dont allow for enough velocity. Bringing the choke point (smallest section of the intake port) to 65% of the diameter of the intake valve, you will gain more hp, and a better intake charge.


it's all there, take a look and spread the word.

[claffix]

and you're building that much material up with JB weld inside your engine? Between this and his break in techniques, I don't know about this guy.

[vile1]

Originally Posted by claffix

and you're building that much material up with JB weld inside your engine? Between this and his break in techniques, I don't know about this guy.

Well, the guy has very convincing testimony
#1, the intake ports dont heat up and JB weld actually has very good insulation properties.
#2 he states he's never had a problem with it coming off
#3 you gring little grip holes for the JB weld to grab when it sets
#4 its not really that much JB weld.

And he's got like 3 or 4 newsletters on his break in technique. Thats under a lot of debate between tons of ppl that dont know what they are talking about.
All i know is my brand new BONE STOCK broken in RS125 using his method finished 2nd place at CMRRA against guys with 250cc 4 stroke motors and ppl with $3500+ in mods to their RS's.

The guy understands racing and how to build a fast bike. I'll definately let you know how it goes.

You can bet on me posting a dyno chart when the bike is done

[StarDeath13]

altho ive never done this type of work in bikes or cars i have done quite a bit of it on RC nitro engines.
and you will be suprized as the gains you can make just by smoothing bores out.
let alone opening them and reshaping them.

and yes useing jbweld is a common practice there also.
some advice ill give you from what ive found by destroying alot of parts experimenting is go small and never over do anything,and copy exactly what you see done thats proven to work and dont be sloppy.
experimenting or deviating from proven mods will usuually result in 80% failure rates,well for me it was that high but i was doing some radical changes.

a fun thing to look into and research is this guys work: http://www.somender-singh.com/
i was able to get some mixed results in applying this into nitro Rc engines.

[vile1]

Originally Posted by StarDeath13

altho ive never done this type of work in bikes or cars i have done quite a bit of it on RC nitro engines.
and you will be suprized as the gains you can make just by smoothing bores out.
let alone opening them and reshaping them.

and yes useing jbweld is a common practice there also.
some advice ill give you from what ive found by destroying alot of parts experimenting is go small and never over do anything,and copy exactly what you see done thats proven to work and dont be sloppy.
experimenting or deviating from proven mods will usuually result in 80% failure rates,well for me it was that high but i was doing some radical changes.

a fun thing to look into and research is this guys work: http://www.somender-singh.com/
i was able to get some mixed results in applying this into nitro Rc engines.

I've read all about Somender's methods and all but I also read about a lot of people that try his method frequently have to clean the grooves of Carbon that builds up there.
I dont have any doubts about it working, I just dont want the bike to be torn down all that often. But it is a viable method.

[StarDeath13]

nothing a few dashes on seafoam wont clear up.
that shit will eat the crabs off of an 80 year old hookers cooch!

[[H]ard|On]

I would think the smoothing is what accounted for most of his gains, not the ghetto epoxy nozzles...

[mhaskell]

I can see that helping on ports that aren't designed well from the factory. On nearly perfect heads like a LSx it will no doubt screw it up

Have you seen the flow numbers for the LS3 heads?

[vile1]

Originally Posted by mhaskell

I can see that helping on ports that aren't designed well from the factory. On nearly perfect heads like a LSx it will no doubt screw it up

Have you seen the flow numbers for the LS3 heads?

No and I bet you havent either.
Heads so perfect as an LS3's would surely create a black hole of infinite flow if ever put on a flow bench....and only God help us then...


haha Anyways, one thing the guy speaks of is the Boundary layer. I remember you stating that roughed up intake ports are useless because of the boundary layer. Mototune says differently. Could you explain this?

[MrBill]

ive always wanted to do sominder's theories on a head, just dont have the balls to do it

[chuckybob]

Originally Posted by vile1

You can bet on me posting a dyno chart when the bike is done

but make sure to get one before and after the head mod!

[StarDeath13]

Originally Posted by MrBill

ive always wanted to do sominder's theories on a head, just dont have the balls to do it

luckily the RC engine parts is experimented with only cost $3 a piece to buy.
id be afraid to try expensive v8 heads.

[u467]

vile1, this was done while I was still in my Formula SAE program. It indeed does work especially for high RPM applications, and we used an epoxy similar to JB weld. I'd cite some sources but don't recall - look for some Formula 1 engine building documents.