Gas Porting

[ADSKIPPY]

What Is Gas Porting A Piston

[Dart Vader]

If I'm not mistaken, this refers to the process where small holes are placed in the piston head that allow combustion pressure to enter the grooves and improve the ring seal.

You might contact one of the big piston manufacturers (Mahle, etc...) for more info on this.

[Awesome Bill]

gas porting allows pressure to enter behind the ring land perfectly spaced to evenly press the ring against the cylinder wall, It is a very small amount of pressure and if your machine shop knows how to hone, it is really not needed. The face area of the push is not large enough to make a large enough difference for proper ring seal. A well honed block will make just as much power or more than a improperly honed block will with gas ported pistons. The ring end gap allows this pressure to get behind the ring while on the compression stroke as well as aid in getting the new fuel air mixture in on the intake stroke. It may help with ring flutter over 7500 rpm and with the larger rings if you spin your engine up there. It is a 50/50 thing that works both ways but not enough for me to take my engine apart to install it. We have dyno tested exact size engines, because we build so many of the same size, with or without gas ported, we have seen no difference at all.

[want-a-be]

Not meaning to cause any conflict here Bill, but I have to dissagree with your opinion.

If gas porting pistons is a crutch for a bad hone job then it would be the same as saying every prostock and nascar engine builder out there can't do a proper hone job. I doubt that you would find any of them NOT using gas porting on their pistons, and I bet they know a little about properly honing their cylinders.

I've built engines with and without gas porting. Some I have gasported on the freshen up. I've had pretty good luck with it everytime I've incorporated it into an existing engine program.

Gas Porting has been around for a very long time. It isn't just some trick of the week. I think it's a step in the right direction. But it shouldn't be use as a crutch for an existing problem. GPing should be use to pull out a few more hp from an already good package.

I do very much agree that the hone job is a very important part of the puzzle, and not all supposed engine builders know how to do one. I'm a bit spoiled with high quality machining of the blocks and heads because of who taught me.


Just my opinion as I am just a want-a-be.

Thanks, Don

[want-a-be]

here is the site to a gas porting tool. You only need common hand tools.
there is a video that can be viewed.

[Dart Vader]

Thanks for that Want-a-be, the link illustrates things nicely.

[Awesome Bill]

no offense taken, but the pistons get this pretty name called gas porting? what is gas porting? This is a simple term that allows compression gases to get behind the ring and help stablize it while it is running threw its cycle. For years when we had nothing but 1/16 compression rings and any rpm over 8000 rpm they would get ring flutter because the rings own weight would lift it off the cylinder wall. Anything under 8000 rpm, your not going to see much if any hp or any increase in real e.t. at the track. We done some pretty good BACK TO BACK testing with gas ported verses not gas ported. Normal bracket engine up to 7500 rpm. We actually lost 3-hp which I don't get upset about because we can only get really within ½% of accuracy. The point is, it did not do any better. Why, this gas porting allow more than normal pressure to be placed upon the ring and will cause drag, it has to. It also causes the ring to wear out faster. If the ring is already sealing under 2-3% on the bench, what little bit you would gain can not get by the ring seal already supplied from proper honing and ring end gap. We have actually opened the ring gap up and did not hurt the power. If the gas ported piston supplied more ring seal then the dyno would prove it. I will agree that nascar running and engine @ 8800-9400 all day needs a little help, they also use a .017" ring, and they throw everything away after it, in that situation they have found it is benificial. Its like dropping a bb into a train coal car, don't do a lot. As fast as the piston speeds are, the natural drag for a little bit of compression to be lost is silly. It happens to fast for the air to get threw. Properely cut rings will not leak compression @ all. It all happens to quick. If you have blow by, you hurt your rings......... We dyno test engines all the time and have posted a ton on the internet and without air pumps hooked up, @ 7400-7500 you can not see any compression in the base problems. Even big blower engines, we start them up and beat their ___ and have no ring seal problems. I would suggest you take some time and do the test yourself. That way its just not an opinion and we all know what they are. There are pros and cons and we install gas ported pistons upon customers request all the time, but we see no measurable difference in power. A properly honed block, high quality Total Seal Ring face, and a good valve job make 10 times the power then a gas ported piston will do. jmo

[want-a-be]

LOL Bill....lets just agree to disagree as this can only escalate.

I've had some pretty talented mentors in the engine building/racing community, and tend to be a little head strong on how I do things. I have also owned my own Dyno shop. I know how to pay attention to details on my assembly. What I do may not always match your way of thinking, but it seems to be working for me.

Thanks, Don

[want-a-be]

Forgot to mention my new creeper on the same site. While your checking out the GP tool chack it out also. It's at....



Thanks, Don

[want-a-be]

Just tore down an engine I freshened up 2 years ago and added gas ports to his combination. Gas ports where the only thing I changed on this engine and he went out and felt a difference in the seat. This engine is in a circle track car and races almost every weekend. The engine is a mildly cammed engine with 12-1 compression. The bore had no more wear then I have seen in engines I've built without gasporting.

Thanks, Don

[want-a-be]

Here is a link to some Reher-Morrison articles. Click on the one that says ...
"The Importance of Gas Ports" This reads pretty good. There are 2 pages so you'll have to click on "next page" at the bottom to see the whole article. Lots of good reading there to boot.

http://www.rehermorrison.com/techTalk/index.htm

Kinda reinforces what I've been trying to get at.

Thanks, Don

[Awesome Bill]

We all know you must of made 20-30 maybe even 50 more hp with that addition if you could feel it in the seat of your pants. WOW! Ofcourse, a DYNO would be a whole lot more professional or even maybe upon taking the engine in, dyno testing it and confirm power, then after a freshen up, you could put it back on a dyno and confirm a power increase or decrease. At least we all know if you have it in print it has got to be true? Give me a break, put some low tension oil rings in or a new 55° valve angle set up or step up to a new cam. The seat of your pants thingy don't work well and we all know that one. A stop watch would of been at the least something.
Like I said, GAS porting is something you can either live with or without and is mostly a nice addition. A vacuum pump will make way more power than a drill bit and some kit to punch holes. 10w30 oil over 20w50 will do better yet. RPM, ring weight, even the type of oil used has more to do with proper ring seal then this handy hole puncher. A 5/64" ring package that will never see 5000 rpm is exactly what I would gas port.
You can gas port all you want and it will be fine. Best thing to do here is just do what you think will work and leave it at that. Hope this thread helped the original poster. It is worth noting that not one OEM manufacture I have ever dealt with has ever allowed gas ported pistons even in their HP line of engines. That would also be foreign or domestic? wonder why?

[want-a-be]

lol...wow...you got me there. I'm having a hard time typing a response at the moment, cause I'm falling out my chair laughing at you. You think you own the only dyno in captivity??? I get up around one. Then bought it after they retired. Got out of it for family reasons.

Wonder why the " OEM manufacture " doesn't use the 55 deg valve job? hmmmm
Or instead of using 10-30 oil why don't we really poor 15-25hp in the oil pan and use 00 or even 000 oil. Why do the " OEM manufacture " not use that.

"You can gas port all you want and it will be fine. Best thing to do here is just do what you think will work and leave it at that."

Thats true.., you build your " not so " awsome engines the way you want, and I will mine.

I have not picked your arm chair troubling shooting apart out of mutual respect. But I see that you didn't deserve what " Little " respect I "granted" you. Your way to quick to jump to conclusions without any facts at all when your trouble shooting problems presented to you here.

Enough said. If were Dart I wouldn't appreciate what I had to say in this post. To them I'm sorry. To you ...I'm not

[want-a-be]

Oh and by the way bill, the site I posted last time was Reher-Morrisons' site. I suppose David Reher probably doesn't know what he is talking about though. How about asking him why oem doesn't run em. BTW...I don't work on many oem stuff. But you might, or maybe oem power is all you can build.

http://www.rehermorrison.com/techTalk/index.htm

Might get some one to read that to you.

[Awesome Bill]

I am not the one not knowing for sure what gas porting was nor did I recommended someone talk to a piston manufacture. Big Mistake right there. Piston manufactures, some, just copy from what is already there. Now a ring manufacture like Total Seal, would be a little better source. We all know you run what you like in your engines and there are places for gas porting and we use them. But I have never just gas ported a set of customers pistons then claim "they felt the power in their pants" lol. we all know that is a really accurate gauging system especially on a dirt track that I can't even think of who would be open at this time of the year. Smells a little funny. As far as RM, lets not bring them into anything without them speaking for themselves. Second hand information is a lot like opinions. We all know what their worth. They really could give a flip about this conversation. I know its nice to buddy up with the big guys and give them their due, but this ain't the first pony ride for us either. As far as this post goes, your happy? I'm happy so lets just let her go. Have fun in the dirt this year and win a championship or something.

[want-a-be]

Dirt isn't the only game I build for. Drag is where I cut my teeth. the seat of the pants I was refering to was in my drag cars, just didn't tell you the times it increased them. and won't. Rm wasn't second hand info. it's off their site that David wrote for the National Dragster on the back page in his tech articles.

[Awesome Bill]

So what? Let it go, you've made your point and everyone knows. Run any type of little trick in the book, thats what we all look for. But I will assure you David is a sharp pencil, but there are tons of sharper ones out there. If you don't believe it, look at who can run competitive in pro stock and comp and who can't qualify or don't even try to? Gas porting thread is over. Let it go.

[want-a-be]

LOL...sounds like your on a coffee buz there bud. Lay off the caffeine some.
I didn't start the thread

[want-a-be]

Hello All. As some of you know I have developed a tool to gas port pistons for. IF you have bought on from online please pm me here.

Thanks, Don

[Awesome Bill]

Wow, no one? I want to hear from you guys on this one!

[want-a-be]

I take it you didn't read the PM it part did you, your on that coffee buzz again aren't you

[Dart Vader]

Hmmm... this thread has turned into an unusually heated debate. Everyone has their own opinions and none of us are always right so try not to be too condescending here people.
I don't mind the discussion continuing (I actually encourage it), but try to support your opinions with sources and relevant info when possible, and try not to start foaming at the mouth...

-DV

[want-a-be]

lol...ok I have no problems at all with the lil rap on the knuckles when I get too opinionated. But Gas Porting is a very established hp builder. Has been proven by alot of very talented builders of engines.

This link is a very good argument towards my claim...

http://www.rehermorrison.com/techTalk/index.htm

not real sure but I think these guys have a lil bit of a rep as quality engine/high hp builders.

Sorry for my part in overly aggresive posts.

Thanks, Don

[Awesome Bill]

Never said they where not and never said gas porting did not help in some way at a certain rpm or even a usable one. Dyno test prove under 7000 rpm your wasting your time and there is much more power to be made in other areas for less. Like Proper head porting, intake, carbs, cams etc. Gas porting is something we only do with high end race engines over 7000 or even 7500 for that matter. If you don't think so, buy a dyno, build an engine, then take it apart, gas port and put it back together and dyno it. You won't see a dime. been there done that. that is all I am saying. everyone has an opinion and its only that, just like mine. At least I have done the test, many times.

[want-a-be]

lol...if you only knew. So have I

[Awesome Bill]

I really do, trust me on this one. If someone has some real dyno sessions lined up with gas p and no gas p back to back, please ring in. In most cases, you can not even see 5 hp let alone doing the actual sweep test with everything being dead on and having that repeatability factored into or out of the final. The only engine we actually saw a gain was a SBF making great power @ 8800-9200 rpm. Ring seal was fantasitic. .043/.043/3mm. And with and without air pump was a real 20 hp difference. So being Glidden built it and dyno tested it with a correction factor of 112% to get 720-22, after we repiared it after it blowed up, our dyno was 720 with only a 106% cf. 2 dynos pretty far apart in 2 different time zones within .1 percent is pretty close. As well as many other engines we have pulled. So, if someone has real data we can sift threw and no some general any one can say anything they want and not prove it other than what they type, please ring in.