mopar1rules Posted July 14, 2008 Report Share Posted July 14, 2008 (edited) i was told and have heard of some people adding "boost ports" or "worm holes", that are 1/4" in diameter to their intake on the cylinders, that lead directly into the transfers. i've seen some photos and am able to do this work myself, but i have also heard that it weakens the cylinder and you have to add some tig weld on the outside of the cylinder. i want to know if its really worth the hassle? so far it doesn't seem like it. i only trail ride and cruise around in the local farmers field, so i need reliability. here's a link to a pic that i was thinking about doing. http://images.google.com/imgres?imgurl=htt...l%3Den%26sa%3DN its on page 3 and its one of the pics on the left side. it will have the discriptions and labeling of the boost ports and size. Edited July 14, 2008 by mopar1rules Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted July 14, 2008 Report Share Posted July 14, 2008 if your building a drag bike then yes. It allows more A/F to enter the crank case . There is more to it then just drilling the whles though, the side shape and angle are all very important. I havent heard that you have to weld anything. Talk to Kevin with Herr Jugs Racing, he can give you some info on it I'm sure Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted July 15, 2008 Author Report Share Posted July 15, 2008 (edited) anyone else? all opinion/facts appreciated. Edited July 15, 2008 by mopar1rules Quote Link to comment Share on other sites More sharing options...
J-Madd Posted July 15, 2008 Report Share Posted July 15, 2008 I don't know of a downside to the boost ports. And yeah, you may have to weld on the outside of the cylinders if the boost ports go through to the outside. Quote Link to comment Share on other sites More sharing options...
XxMeltIcexX Posted July 15, 2008 Report Share Posted July 15, 2008 Mine dont have any added material for the boost ports... Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted July 16, 2008 Author Report Share Posted July 16, 2008 maybe the tig welding talk came into play with the talk of triple exhaust ports and i just mixed 'em up? Quote Link to comment Share on other sites More sharing options...
spurdy Posted July 16, 2008 Report Share Posted July 16, 2008 (edited) maybe the tig welding talk came into play with the talk of triple exhaust ports and i just mixed 'em up? I've seen boost ports that broke through the cylinder and were welded back up. It has been 8 or 10 years ago, and if I remember right it was a Paul Turner port job. SP Edited July 16, 2008 by spurdy Quote Link to comment Share on other sites More sharing options...
Wildcardracing Posted July 16, 2008 Report Share Posted July 16, 2008 I haven't had much luck seeing any real gain with them in my portwork. I know passion uses them, there are some good pictures of them on his website (that's what his 12port is). 1/4 inch holes wouldn't require any tig welding, but I'm sure to see a gain you would have to go bigger and also cut an additional port window into your rear transfer port. They claim it helps low speed atomization and high speed flow. I'm going to play with them more extensively on my next personal engine. You can find a link to passions website in the dealers area of Noss machine. Quote Link to comment Share on other sites More sharing options...
wesw Posted July 17, 2008 Report Share Posted July 17, 2008 (edited) here are some pic of my old 12ports that jim did. he did drill thru the side and re welded it up and made it look nice. Edited July 17, 2008 by wesw Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted July 17, 2008 Author Report Share Posted July 17, 2008 nice pics. i'm still debating while the engine is apart here. to me its a toss up. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted July 17, 2008 Report Share Posted July 17, 2008 Some builders don't need to weld anything on the outside. Triple exhaust ports is more critical than the work holes, IMO.... Quote Link to comment Share on other sites More sharing options...
XxMeltIcexX Posted July 17, 2008 Report Share Posted July 17, 2008 Holy shiznit, ya those are huge... Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted November 16, 2008 Author Report Share Posted November 16, 2008 I haven't had much luck seeing any real gain with them in my portwork. I know passion uses them, there are some good pictures of them on his website (that's what his 12port is). 1/4 inch holes wouldn't require any tig welding, but I'm sure to see a gain you would have to go bigger and also cut an additional port window into your rear transfer port. They claim it helps low speed atomization and high speed flow. I'm going to play with them more extensively on my next personal engine. You can find a link to passions website in the dealers area of Noss machine. slobanshee, did you ever get the chance to play w/the boost ports on your personal engine yet? Quote Link to comment Share on other sites More sharing options...
Wildcardracing Posted November 16, 2008 Report Share Posted November 16, 2008 I found that they did offer a minor low to mid power increase at the expense of some top end power with my portwork. I didn't however cut the added windows in the sleeve. I ended up filling them in and haven't messed with them since. I have found a lot more power playing with transfer durations and angles as well as experimenting with exhaust port shapes. Honestly to see any real gain with the boost ports on a stock cylinder setup I think you will have to have them welded so you can go larger and add the windows. My best advice is to try it for yourself and see if it works for you. What works with one builders portwork doesn't necissarily work with anothers. Quote Link to comment Share on other sites More sharing options...
XxMeltIcexX Posted November 16, 2008 Report Share Posted November 16, 2008 I found that they did offer a minor low to mid power increase at the expense of some top end power with my portwork. I didn't however cut the added windows in the sleeve. I ended up filling them in and haven't messed with them since. I have found a lot more power playing with transfer durations and angles as well as experimenting with exhaust port shapes. Honestly to see any real gain with the boost ports on a stock cylinder setup I think you will have to have them welded so you can go larger and add the windows. My best advice is to try it for yourself and see if it works for you. What works with one builders portwork doesn't necissarily work with anothers. Glad you followed up, Mine are not large at all and are set up for drag. Although my friends K&T has added material and they are similar to the ones dave posted, and they haul some ass..... How large were the ports on yours Slo? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.