Anyone brave enough to port your own head??

[Wheel House Motorsports]

Just curious if anyone has done there own, i have played with my old 350 chevy a bit years ago but was thinkin about the 1 ton motor and trying to squeeze even more power out of the wild machine. i looked at the nytro stuff and have learned some, just curious if anyone had any input. I will get back into it and re-read a lot of books i have on the subject. just lookin for some sled specific stuff.

 

[throttlecable]

I understand the desire to take on a do it yourself project like that,...but why not just spend the cash on a professional port job from a reputable shop? At least you would have the piece of mind that indeed the motor will be 15-30 horse stronger, and more importantly, you didn't "F" anything up that will end up costing you more $$ than having it done professionally.

 

[Vertical-Extreme]

I thought you were only running 12 or 15 lbs of boost on propane. Turn that thing up to 20lbs. If you want more power. They will run at 20+ all day

 

[tjc]

Everyone has to start somewhere, cant fault him for wanting to learn

 

[Wheel House Motorsports]

I thought you were only running 12 or 15 lbs of boost on propane. Turn that thing up to 20lbs. If you want more power. They will run at 20+ all day

its more the response and getting to the big power.. 15-16 is what i have been running it at lately. im taking my headshim back out this summer and getting more bottom end out of it was sorta the goal. THe wot power is more then enough for me.. im only 150#, so the sled hauls *** with me on it. I just want something with more of a broad powerband as right now its VERY on/off.

if its something that is way out of my leauge I understand, but I know like most things, with a little learning, some caution, and a lot of time, you can make it work halfway decent. and i DONT pay people to do things for me. i want to learn/know, sometimes it works out well, others not great, but im in it for the knowledge.

 

[XtremeSpeedShop]

I wouldn't be to worried about messing something up as much as I would be doing a lot of work with little gain. A lot of times porting with out bigger valves wont do very much and there is huge difference from "opening" up the ports and designing them to give a straighter shot into the cylinder, increase air speed yadyadyada. When done right though it does help spool up greatly! Porting is what I would do after you make sure you have a good header design, correct turbo, cam timing set up, fuel dialed etc. But after saying that , most Pro's started with a dermel in the garage

 

[Wheel House Motorsports]

appreciate the post.. and coming from someone who does porting, i can take you VERY seriously. I admit, lots of work and possible gains are something i am used to... my sled is a neverending battle to make it better, sometimes i do a lot of work and get nothing, other times i do. its all about fun and learning to me and showing up on the hill with something that is 100% my work and knowledge, not what someone else did and I bought.

as far as header/cam etc etc etc... header is pretty solid, almost an identical impulse replica slightle modded for my chassis setup. cams are stock with adjustment to powderlites specs.. fueling is still a hair off, but the propane has a hard spot to tune, but slowly getting it worked out. im just looking at slowly making it better and better. and its something i can work on in the summer.. worst that happens is i burn up some time... but thats kinda the nature of learning.

 

[BigFish BC]

i know a exuast cam on the intake side works well on the nytro to help with throttle responce & a bit more power.

 

[irondave86]

I say give it a shot, Like ya said, do your homework, be cautious and cross your fingers for luck. It might be a lot of work with only a little gain, but a little gain is better than no gain.... don't forget to post pictures!

 

[Zipperno]

We have ported a couple of Nytro/Vector heads. Some work has to be done to both ports but nothing huge. But the seat area needs some work. Inlet seat has a step that needs to be smoothed out to let itflow good.

 

[kinger9]

I ported alot of heads back in the day for the ford duratec engines which were pretty efficent little buggers. We could sqeeze out about 15 more hp but it was a TON of work each head.

In the end we had 3 cuts, a SC cut, TC, cut, and nitrous cut. The SC had larger intake ports, the TC had larger intake and exhaust ports (the easiest one to do not much guessing make it flow as much as you can), and the nitrous had larger exhaust ports.

Its important to fix and work the transition between the floor and ceiling we called it. Mimimize the curves and straighten out the path right to the valve. We would even cut some of the valve seat to pick up a few more CFM.

In NA heads they are EASY to screw up, not enough air speed and they are ruined. In a turbo they are the easiest to NOT screw up, basically more flow the better on a Turbo engine. One thing you'll find though is it will give you the opposite effect of what you want, if you want more bottom end, we would make the ports SMALLER to increase air speed velocity into the port, very quick responsive head but sort of limited on high end HP.

The yammie 4 cyl heads are so good your not going to get much out of them, also important do not smooth out the ports to glass smooth you need the surface roughness to create the little eddies and effectively 'shrink' the port to up the air speed velocity.

The proper bits to do this by hand are spendy you'll have a few hundred in drills, bits, etc to do it. The ole 3/8" drill is not what you want for this.

Have fun be ready for sore back, hands, fingers, for little to any gain, but at least you can say you did it.

 

[Wheel House Motorsports]

I actually have access to die grinders and handfulls of really nice bits (hurray for friends) so my financial investment should be minimal, only time which isnt worth a whole lot these days.

I do appreciate all the input guys. Im more then aware of how a lot of projects may seem simple and easy power but how in reality it is far from it, after this summer my sled will be built 100% by me, so im aware of how much work goes into these type of projects.

And like i said, back in the day i did a lot of reading and a little bit of playing with sbc heads, so i have a good idea of where to go with it and what is a good plan, just was curious if anyone had any yami specific info/hints to lend.

after the 4th of july when im done riding and take it all apart I will see how brave i feel then, but im confident I will at least try a LITTLE bit. I know my exhaust ports can use some love as they are a hair smaller then my header tubes ID.

 

[HDEMWET]

I've done my own porting back in my 2-stroke days, with a lot of success. it was mostly matching the exhaust port to the size of the pipe hanger and polishing that side to a mirror finish to limit carbon buildup. On the intake side I'd knife edge the transfer ports and match the intake to the carb boot opening. as mentioned no polishing on the intake side, the extra turbulence of bumps and crevasses helps atomize the a/f mixture. I've never tried a 4 stroke head though, it seems like a daunting task. I understand wanting to do everything for yourself and applaud you for it. please post pics if you decide to do it, i know i for one would like to see how you make out. good luck

 

[E&S]

porting

I have a Nytro head that dropped a valve in one cyl, It would be perfect for practicing different things-Let me know and I can ship to ya. Darren

 

[knifedge]

--You may want to test each port on a flow bench to make sure the intake ports and exhaust ports are flowing equally for equal power output from each cylinder.

--Turning up the boost would be alot easier than dissecting the head though.

 

[AKSNOWRIDER]

I have ported V-8 heads...both race and street stuff..I agree with what the others are telling you..tough job on a N/A motor, but not impossible..I will say this, for throttle responce, bottom/midrange power...think about mid lift flow areas(or lack of) ..hard to describe but best way to figure it out if you dont have the right stuff(flow bench, dyno and such) is find a few stock heads and try a few drastic things and see how the motor responds..whichever one works the best...concentrate on those type of changes and see how far you can go with it..I used to take a set of cast iron truck castings(big block chevy) and proceed to put about 40 hrs of welding and grinding into each head to make a trick set of race street heads that would lay a whipping on a set of LS-7 big port factory heads(this is before the advent of quality aftermarket heads)..all it takes is time ..old nascar racer grumpy jenkins had a few good books out that explained alot about port work and how they relate to performance..might be worth a read...

 

[slash]

just watch your short turn radi if these get to shallow it kills flow ,the post with pics looks real good dident remove too much just remove flaws and make it smooth

 

[roughrider99]

This is something that I was really interested in, but due to lack of time and proper tooling, also having a hard time finding good info about. It has held me back. I too liken to do my own work but most of the time. I can't build anything up to my own standards, so I save and cough up the cash

 

[t_thall]

Modern 4 valve heads are very good from the factory, just clean up all casting flaws and match the ports. You can smooth any flaws in the chamber also to prevent hot spots. Be very careful if your using an air powered grinder or any type of larger, harder to control grinder - one catch of the bit and you can very quickly take out a valve seat or head gasket surface, doesn't take much! I use a foredom grinder, electric motor is seperate and controlled by a footfeed, gives it a nice light and small handle...