SLORYDER Posted October 21, 2009 Report Share Posted October 21, 2009 (edited) Now, let me start off by saying that I fully understand the risks involved in doing your own porting. I know that you can ruin a good set of cylinders by taking off a half millimeter of material in the wrong place. I also realize that it takes alot of expensive tools to do a worthwhile job. I plan on buying the necessary tools ($450 something bucks) and trying to do some grinding myself. And my questions are basically refering to a top end/ not quite full drag setup that I don't have to replace my ringson every couple months. 1.Exhaust port; i realize that you have to be careful on how wide you go on your exhaust, what is a good safe percentage of bore? 70%? 2. Intake ports; I realize you can gain power by widening the intake port, and I know you can easily snap off the intake brige and destroy your entire motor by opening it up too much, but what effect does intake port timing have on the powerband? Will raising the intake ports give you an increase in top end? Or is it best to widen them a little but generally leave them alone? 3. Transfers; Do you get any gains by opening the tunnels or do the gains come mostly from raising them? And I'm pretty sure the angles need to stay the same, right? 4. Boost port; are there any good gains to be had by widening the boost ports or widening them? 5. Also , I know there are timing durations like 155/ 185 (not accurate), but what do they mean. I plan on getting a degree wheel and all; are those numbers reffering to degrees of crank rotation from BDC that it takes for the ports to close, or degrees before TDC? I am confused. And if someone can give (pm) me a good number to start with I'd appreciate it. I know this is a lot of crap, but if you can answer just one that would be helpful. Thanks. Edited October 21, 2009 by SLORYDER Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted October 21, 2009 Report Share Posted October 21, 2009 (edited) 5. Also , I know there are timing durations like 155/ 185 (not accurate), but what do they mean. I plan on getting a degree wheel and all; are those numbers reffering to degrees of crank rotation from BDC that it takes for the ports to close, or degrees before TDC? I am confused. And if someone can give (pm) me a good number to start with I'd appreciate it. no one can give you any specs/durations etc, until we know your pipe, and riding style. also, if someone says that they have an exhaust of 188* and main transfers of 124*, that would mean the exhaust port is open for 188* of crank rotation and the main transfer ports open for 124* of crank rotation, and that the blow down timing (which is very important) would be 188*-124*=64*/2=32* blow down. Edited October 21, 2009 by mopar1rules Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted October 21, 2009 Report Share Posted October 21, 2009 You need to read a couple two stroke tuning books before you guy and try to port your motor. This is all stuff you should know, and not be asking us if your going to port them yourself. Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted October 21, 2009 Author Report Share Posted October 21, 2009 (edited) no one can give you any specs/durations etc, until we know your pipe, and riding style. also, if someone says that they have an exhaust of 188* and main transfers of 124*, that would mean the exhaust port is open for 188* of crank rotation and the main transfer ports open for 124* of crank rotation, and that the blow down timing (which is very important) would be 188*-124*=64*/2=32* blow down. I will be running PT hi revs'. My riding style is pretty much on or off. Cruising or wide open blasts on the beach/ drag racing. I don't want a severe on/ off powerband though. Like 3/4 full drag. What would be a good timing advance? I'm at sea level if that makes any difference. And about the timing numbers....How would one go about measuring that 188*? Zero the wheel at the bottom of the exhaust port and rotate to the top of it? And is this done with the base gaskets in place? Edited October 21, 2009 by SLORYDER Quote Link to comment Share on other sites More sharing options...
AKheathen Posted October 21, 2009 Report Share Posted October 21, 2009 once again, measure from when the port opens on the downward stroke, untill it closes on the upward stroke .......read the books! you can also find the specs on your pipes online Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted October 22, 2009 Author Report Share Posted October 22, 2009 once again, measure from when the port opens on the downward stroke, untill it closes on the upward stroke .......read the books! you can also find the specs on your pipes online Yeah I have the "two stroke tuners handbook" and it sparked my interests but I work 10/7 and hardly have time to read much. Thanks for the info Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted October 22, 2009 Report Share Posted October 22, 2009 Would you shave your face, then put on shaving cream? Why would you port the motor, then read the book? You would have the answers to all these questions if you looked in the book. I dont mind helping people, but I am not going to do the work for someone else who feels they don't have the time to apparently do it right. I didn't exactly have the time when I read the book, and when I searched on the internet for the formula programs myself. I personally dont want to help you, and I dont think anyone else should help you until you show the initiative to research what your doing first. You need to become an expert before your ready to grind on a set of jugs. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted October 22, 2009 Report Share Posted October 22, 2009 i work 7-12's and still have a couple hous each night and in the morning to get on here, and read, rebuild my laptop, repair sterios, etc.......and i need at least 8 hrs..............just sayin Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted October 22, 2009 Author Report Share Posted October 22, 2009 By the way my transfers have been raised about 1.5mm (by a reputable builder) and from what I gather in the books for top end power the transfers don't need to be raised all that much, mostly for giving u a broader powerband and from what I understand may lower your top end hp. Maybe playing with the angles could help but I'm not even to attempt that at this stage. My exhaust has been raised and widened about 1.5-2mm but I'm sure there is still a lot of power to be had. And I haven't checked the timing yet either...I'll prolly order a degree wheel on friday. So from what I gathered I'll try for about 66% on the exhaust width, and chamfer the walls really good but I'm still not sure about the duration... Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted October 22, 2009 Author Report Share Posted October 22, 2009 Would you shave your face, then put on shaving cream? Why would you port the motor, then read the book? You would have the answers to all these questions if you looked in the book. I dont mind helping people, but I am not going to do the work for someone else who feels they don't have the time to apparently do it right. I didn't exactly have the time when I read the book, and when I searched on the internet for the formula programs myself. I personally dont want to help you, and I dont think anyone else should help you until you show the initiative to research what your doing first. You need to become an expert before your ready to grind on a set of jugs. Actually, I read a good amount in the book since my last post (I had some down time due to heavy rain here in LA.) And please don't act like you know me (I am not going to do the work for someone who FEELS they don't have time to do it right). I work every day in texas, drive back and fourth to louisiana, have a pregnant wife a 3 year old and 5 dogs at home to tend to. don't think you are in the position to be making judgement calls on me and i you don't have anything positive to say just don't post in my topic please. Quote Link to comment Share on other sites More sharing options...
SLORYDER Posted October 22, 2009 Author Report Share Posted October 22, 2009 (edited) i work 7-12's and still have a couple hous each night and in the morning to get on here, and read, rebuild my laptop, repair sterios, etc.......and i need at least 8 hrs..............just sayin 7/12's? You must work on the pipeline or the slope? I worked there for about 5 months (570 inspector). Yeah I have a wife and kids. It's a little different bro. And I don't have internet at home either. Just my work computer, or I'd probly go home and search and not be posting this topic at all. That's cool though if you don't think I deserve any help. Edited October 22, 2009 by SLORYDER Quote Link to comment Share on other sites More sharing options...
RZBansheeMan Posted October 22, 2009 Report Share Posted October 22, 2009 Maybe "Snoop" should stop being such a fucking ass plug all the time, you always have such snide answers for everything, you act like your such great help, but in all actuality you're not. Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted October 22, 2009 Report Share Posted October 22, 2009 Hey man, cruise over to planetsand.com and get a subscription over there. There are a lot of professional builders over there who throw around porting information a lot. Numbers, durations, specs, etc. You will find answers to a lot of your questions there. My advice would be to go get some stock cylinders and some ported cylinders from other builders and measure their cylinders and just start practicing on the stockers. That along with the books out there and you can figure out the basics and just build on up from there. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted October 22, 2009 Report Share Posted October 22, 2009 7/12's? You must work on the pipeline or the slope? I worked there for about 5 months (570 inspector). Yeah I have a wife and kids. It's a little different bro. And I don't have internet at home either. Just my work computer, or I'd probly go home and search and not be posting this topic at all. That's cool though if you don't think I deserve any help. i work the mine on big ass tractor/trailers, i also have wife, daghter, mother-in-law, to support/entertain....my back is so messed up i need to stay so fucked up on pain killers that only take the edge off that i can hardly function, but still do. the way i see it, you have 6hrs of personal time, provided you sleep the whole 8 hrs. not saying your day is loaded or you don't deserve help, i just don't respond well to whining....... why no internet? i'd be taking my kids to mcplayland and surfing, if you have a laptop. just a suggestion. so, what were we talking about? Quote Link to comment Share on other sites More sharing options...
papa_smurf49319 Posted October 23, 2009 Report Share Posted October 23, 2009 Unless your trying to make a buisness out of this, by the time you spend the money on the tools, and read the books, and actually spend the time to learn it your better off just sending it out. Believe me i love to do everything myself and hate sending my stuff out, i rebuild trannys, engines, etc and never ever take any of my vehicles to the shop. But one thing i do do is send out my cylinders to get ported. If you really think about it, and the time they put into the set its really not that expensive. If i was going to start a buisness though, i would get my cylinders ported and just look and see what other builders are doing. Maybe its cheating, but thats how every buisness works, they want to know what the competitor is doing. Sorry for the long babble but we just want to know what your trying to accomplish. Cody Quote Link to comment Share on other sites More sharing options...
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