registered user Posted December 14, 2015 Report Share Posted December 14, 2015 His specs were to make the exh that shape or was that your own idea ? I have a feeling he may have only gave you a small bit of info and not the whole book. Look man I was just saying don't cry if they're door stoppers. Wasn't trying to be a dick. It's just part of the business. Call it School of hard knocks if you will Quote Link to comment Share on other sites More sharing options...
bigweav81 Posted December 14, 2015 Report Share Posted December 14, 2015 I've read time, and time again about how shitty looking port jobs have been known to scream. I think a lot of the flawed look is the type of tools. Practice makes perfect, and no I don't port, but I am a dentist. sent from yo mammy house. Quote Link to comment Share on other sites More sharing options...
registered user Posted December 14, 2015 Report Share Posted December 14, 2015 I don't see anything wrong with the look or air tools but you have to be careful about raising ports that high or strange things can happen as many of us have found out. Normally I recommend starting off with them a bit lower but everyone needs to see for their self 1 Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted December 14, 2015 Author Report Share Posted December 14, 2015 They aren't fiinished yet, i still have to sand the ports out and polish the exhaust. When i degreed the ports in the ex only got raised about 2ish mm and the trans about the same. I started with virgin 64mm cylinders. These pics are of just the rough in. Why won't a squared ex port work? I've seen lots of old school port jobs with squared ex ports scream. 1 Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted December 14, 2015 Report Share Posted December 14, 2015 Specs from Tom himself. I don't know if this was for a stock stroke or 4mil though. The rockets are a pretty decent pipe, but to get them to rev, they need a fairly brutal exhaust duration. On my 4mm, it actually didn't seem to hurt the bottom end much going from a 196-200*, but it really let it charge up top. Same motor with shearers obviously revved out better up top, but had no where near the bottom end as the same combo with rockets. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted December 14, 2015 Report Share Posted December 14, 2015 I've seen a lot of exhaust with the squarish shape and they run well. But you need to make sure the transitions at the outer edges where they meet top and bottom have lots of attention. The guy I learn a lot of this from swears by the shape being like that, but is always very quick to show a collection of really fucked up pistons from projects that come in from other builders where they barely blended it and just chamfered it. Quote Link to comment Share on other sites More sharing options...
registered user Posted December 14, 2015 Report Share Posted December 14, 2015 I never had much luck with flat roofs. Tried it on a Honda and chewed the rings pretty fast. On my 4mil everything is mostly opposite of what Tom describes so it'll be interesting to see how it turns out. That post from Tom is over 10yrs old. I wonder if he would still recommend the same specs or maybe times have changed Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted December 14, 2015 Author Report Share Posted December 14, 2015 The specs i got from 2 weeks ago are identical to the ones Tricked just posted. Same exact specs. I know from my days of Maico dirt bikes, when you have a flat roof you need a generous chamfer. Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted December 14, 2015 Author Report Share Posted December 14, 2015 Tom* Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted December 14, 2015 Report Share Posted December 14, 2015 It would of been nice to see the bridge in the intake with a little more meat left. With the transfers welded, you can take out a bit more meat. Especially on the divider all the way up the transfers. Last, the boost port is a minimal gain unless you really work them. Make it worth your while and get them opened up. You don't seem to have a problem welding on these things, so it wouldn't be to big I an ordeal if you go through. 1 Quote Link to comment Share on other sites More sharing options...
registered user Posted December 15, 2015 Report Share Posted December 15, 2015 I think the bridge should be fine. They were only 5-7mm wide on the KTM stuff and did ok Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted December 15, 2015 Author Report Share Posted December 15, 2015 It would of been nice to see the bridge in the intake with a little more meat left. With the transfers welded, you can take out a bit more meat. Especially on the divider all the way up the transfers. Last, the boost port is a minimal gain unless you really work them. Make it worth your while and get them opened up. You don't seem to have a problem welding on these things, so it wouldn't be to big I an ordeal if you go through.The transfers need some more work for sure. im afraid to go any further until i get the angles correct, then I'll blend them all the way, and get that divider a little thinner. As far as the boost parts. How much bigger can i go? Can i take it all the way up to the sleeve? Can i make them taller? As of right now, id say they're just over 3/8" dia. but i haven't measured them. Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted December 15, 2015 Report Share Posted December 15, 2015 I'll dig for photos. A sled guru out here is always telling me they gotta be big, or it's not worth the time. Lots of guys just drill holes and blend around them, but if you look hard, the guys making a difference with them are getting pretty wild with them. Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted December 15, 2015 Report Share Posted December 15, 2015 Passion. You'll need to weld to get this large. Little small, but I posted it so you can see what was done down the intake wall in effort to force air in to the BOYHESON ports. Wish I remembered what the videos were called, but these things screamed up hills in the dunes. Sent from my iPhone using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
bigweav81 Posted December 15, 2015 Report Share Posted December 15, 2015 Passion. You'll need to weld to get this large. Little small, but I posted it so you can see what was done down the intake wall in effort to force air in to the BOYHESON ports. Wish I remembered what the videos were called, but these things screamed up hills in the dunes. Sent from my iPhone using Tapatalk That second photo is neat. sent from yo mammy house. Quote Link to comment Share on other sites More sharing options...
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