Any one done thier own port work. I have a set of stock heads laying around and contemplating doing it. I would probably screw them up but since I only payed 100 bucks for them whats the difference.
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Any one done thier own port work. I have a set of stock heads laying around and contemplating doing it. I would probably screw them up but since I only payed 100 bucks for them whats the difference.
I had the stuff to do it and chickened out. I don't think it is that hard, but harder to reverse if you screw up.
posted with my rooted and ICS'd T-bolt using tapatalk 2.
im not scared of screwing them up to be honest. If i screw them up while they are on the bench then okay im out a 100 bucks and chuck them in the trash. Im worried about having an uneven port jobs and having uneven airflow to the cylinders. Im thinking about just smoothing out the castings a little. I read online that is good for 10-12 cfm usually. I have a bunch of videos i may watch and see what i learn.
my other big thing is tuning.
I just want to hear from other and get opinions
The valve job is huge, that is the machine shops job though. You can streamline around the valve guides, and remove any casting flash. Then gasket match the intake opening, paying extra attention to the top. That is where the majority of the flow is. Also a little bit of bowl work. You do that from the chamber side. You don't want a sharp transition from the valve job into the short side radius. Just don't go hog wild. Once you get one cylinder done to your liking the rest will go smooth. Wear good goggles too, that aluminum gets everywhere.
Good info joelster. Im going to let the machine shop do the valve job. Im gona do the porting first then take it to the machine shop unless someone says that i should do it the opposite way. Im gona give it a shot in a few weeks. eastwood sells a kit so ill pick that up. Ill take pictures so you guys can look at it and correct me where i go wrong.
I did mine. I had the heads shaved as well as new seats and valves installed after I finished. Like joelster said, don't go hog wild. You'll be fine.
Good Info here. You can skip the kit if you have a local harbor freight and northern tool around. I used a rotary burr set that I picked up from Northern Tool to do most of the material removal. I then used HF's sanding cone kit to do the finishing touches on the ports. http://www.harborfreight.com/52-piec...set-96826.html. Take your time and try HARD not to nick the valve seats. You can smooth the ports out, gasket match the intake ports and clean up the ridges and casting flaws under the valve seats. You can also take a 1" wide by 1.0-1.5' piece of emmery cloth and run it back and forth along the short side radius to help smooth that out. Its almost impossible to get to with a burr or sanding cone.
Here are some pics of a set of heads I did a wile back. They made a noticeably increase in power but I never got the engine tuned or to a dyno... http://s1093.photobucket.com/albums/...ead%20Porting/
good info guys keep it coming. I really appreciate the photos and information everyone. the Eastwood kit is the same kit just 10 bucks more lol http://www.eastwood.com/engine-porting-kit.html . I am a frequent visitor of harbor freight I think they know me by name lol
Quote:
Originally Posted by Viper
Read my posts tried to provide good information and pictures.
http://www.ls1lt1.com/forum/lt1-|-lt4-|-l99-engine-tech/52576-lt1-cam-install-2.html
Easiest to do 1 thing to all ports at a time.
Then heads are useable at all stages.
Flow is at the top on intake and exhausts.
The exhaust ports are easiest to work lips or ridges off the sides don't lower the bottom step angle down from top past guides on sides clean all casting flash as close to gasket matching all ports.
Try to make all ports the same size and shape.
Match the 1st 1/2 inch of the intake ports and the intake manifold.
The curved area do not remove much called pushrod pinch area look at valve seat area only top 2" of port on curved side remove casting flash and square to valve pockets.
Most flow improvements are in the valve pockets smooth valve job below guides into port shape path around guides.
Here is a simple method to LT1s Gasket match 1st 1/2 to 1 inch of intake opening and manifold.
Polish all valve guides and slightly shape the sides into upside down U or V shape allowing .125 inch material around the guide.
Exhausts square up sides, angle down from top past guides barely touch up roofs and floors to remove casting flash.
A simple extrude porting on cast iron heads or exhaust manifolds sand blast and smooth. Removes casting flash similar to extrude porting. Best to match
port openings then sandblast inside runners.
Don't sand blast aluminum its too abrasive and eats throught the metal. You can bead blast casting flash off of aluminum to smooth it up. Circle track racers in limited classes can't port heads or manifolds but this is a way to improve flow.
Even simpler porting Match intake gaskets 1/2 inch into port. Completely polish existing exhaust ports with 220 grit or finer. Enlarging exhaust with coarse grit is nullified by carbon build up after the 1st few miles. Polishing increases flow and velocity without enlarging the existing port shape. Only on exhaust as fuel puddles on intake ports unless rough finish except on valve guides.
I got a chance to read some of the links earlier. I am going to finish reading the rest tomorrow.
With aluminum use coarse grinding stones and sand cartridge rolls to shape aluminum do not use carbide burs and cutters even ones designed for aluminum removes too much metal too fast. Keep the cartridge rolls moving slightly or it will create dips and ridges touching and shaping. Clean up the ports don't try to enlarge them or change their shape drastically especially on the tops and floors you'll find the water jackets. On the sides of the intake if you try to straighten the curve in the pushrod pinch are youll go through the casting to daylight. Try to make all the ports identical that way you get similar power from each cylinder.
The reason they say not to enlarge intakes to gasket match is porting shops pay money to their employees to do as much in as little time as possible. General administrative costs, shop support, and overhead reduce these = greater profit margins.
Not matching the ports to the gaskets but just the openings(1/2to1") along with the opening on the intake insures even consistant flow to each cylinder. Think of the port like a funnel or a cold air intake K&N and Moroso start large and unrestricted taper down to increase velocity and smooth transition past valves into combustion chamber. Porters use templates to hand port chambers CNC use flow tested heads digitized into the computer to replicate the template or pattern design.
Use a Dremel or 1/8 inch tool to smooth valvejob diameter into ports and shape valve guides. Use 1/8 and 1/4 electric or air die grinder to shape debur the ports. An electric varible light dimmer switch can be used to control the speed of the porting tool. Use a slower speed on aluminum it cuts faster and remove the valves.
Place clamp on light to see your work inside the ports. Use 2x4s to hold the heads in positions to port. Lastly do not use glasses to protect your eyes I almost lost an eye from this. Use Goggle or a face shield and do not breathe in the grinding material kleenex in nose or respirator. Most guys want to make the intakes larger but the exhaust are easier to do and flow less. Results just polishing exhaust ports and manifolds or adding headers makes the engine rev much faster I've done this on lawn mower engines 3 wheeler atv's 4cyl engines inline 6cyllinders v-8's and radio controled airplanes.
DON"T try to ENLARGE the PORTS iv'e ground through so many things if I get carried away or distracted just clean smooth and polish.
Match and remove imperfections in the castings.