dirtydownunder Posted January 30, 2012 Report Share Posted January 30, 2012 i think you need a steadier hand Quote Link to comment Share on other sites More sharing options...
DwnSouth Posted January 30, 2012 Author Report Share Posted January 30, 2012 i think you need a steadier hand It's not as easy as it seems!! Lol Quote Link to comment Share on other sites More sharing options...
sprinklerman Posted January 30, 2012 Report Share Posted January 30, 2012 Props for experimenting man! Shoot, as cheap as stock cyls are these days,why not do some playing with them,,, if you are having fun. Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted January 30, 2012 Report Share Posted January 30, 2012 Your work is looking very good so far. Never seen any jugs with the two holes in the sleeve there. Is this your idea or is it "borrowed"? Unfortunately I would have to see some dyno numbers to show it's usefulness. Only suggestion I have is the sleeve should be beveled at the bottom at the transfer tunnels. Quote Link to comment Share on other sites More sharing options...
ham354 Posted January 31, 2012 Report Share Posted January 31, 2012 Dwnsouth I have a set of coony ported cylinders on my stock stroke bike and they perform incredible. Should be interesting to see what yours are going to run. What pipes and carbs are you going to run with these? Quote Link to comment Share on other sites More sharing options...
Coupelx Posted January 31, 2012 Report Share Posted January 31, 2012 Your work is looking very good so far. Never seen any jugs with the two holes in the sleeve there. Is this your idea or is it "borrowed"? Unfortunately I would have to see some dyno numbers to show it's usefulness. Only suggestion I have is the sleeve should be beveled at the bottom at the transfer tunnels. the holes in the sleeve are kinda like a short cut for the mixture under the piston to get into the transfers. Quote Link to comment Share on other sites More sharing options...
Redline Racing Posted January 31, 2012 Report Share Posted January 31, 2012 I have played alot with boysen ports. On my 350 I pulled cylinders off while on the dyno added boysen ports reinstalled them. They did improve HP, it made .070 hp more. On my twin cougar which has large boysen ports I epoxied them up while on the dyno made exact same hp. Mtr was a little less responsive at low rpm but showed no loss in hp any were on curve . Not saying they aren't a good thing just saying there is more in angles and shapes than extra holes. Quote Link to comment Share on other sites More sharing options...
SonOfSand Posted January 31, 2012 Report Share Posted January 31, 2012 I have played alot with boysen ports. On my 350 I pulled cylinders off while on the dyno added boysen ports reinstalled them. They did improve HP, it made .070 hp more. On my twin cougar which has large boysen ports I epoxied them up while on the dyno made exact same hp. Mtr was a little less responsive at low rpm but showed no loss in hp any were on curve . Not saying they aren't a good thing just saying there is more in angles and shapes than extra holes. Very interesting. Is there something to be gained by working the "angles and shapes" of a as cast 4 mil cub? Or are they already optimized? Quote Link to comment Share on other sites More sharing options...
camatv Posted January 31, 2012 Report Share Posted January 31, 2012 hmm basic porting 101 tells us that for low end and midrange the boost ports are mostly for broading the powerband out.. BUT they can also hlep a drag motor in a way with some differnt angling.. IF you really really really think about what possibly might be going on in there..... so yea big ass CC motor thats got a very narrow actual powerband in the upper rpm limit of the rotating assembly is probably not going to see an improvement from boost ports escpecially one that is blowing the wrong direction.. the ports in the sleeve im not sure what to think about that.. i rember seeing them from jims old oem cylinders but never really seen a before and after effect shown on a dyno.. whats funny to me on your cylinders is how rough they look and how they seem ( to you) to run pretty good... you better start buying some rings and pistons. bet its going to eat them alive. already looks like the top of the port is getting beat up.. yea everyone needs a starting point and if your tired of paying for the work adn dont mind spending about 5 times what a port job would cost on proper tooling and time for technique building then for all means go for it!! there have been many a blown up motor in trying to figure out what "works" and truthfully with out a dyno you cannot really push motor's to their absolute max. only thing you can do is your own "theriories and real world" testing.. id LOVE to see a redline super basic port with the knowledge he learned from all that time he took on the stockers . just take a virgin set. do JUST cylinder porting angles and port dimensons known to work. basic basic work on the intake. and basic work on the transfer bridge.. just round it our and smooth out the casting flaw's.. then slap them on and really see if all the other work with smoothing and cleaning these things up is really even dooing anything.. Quote Link to comment Share on other sites More sharing options...
DwnSouth Posted January 31, 2012 Author Report Share Posted January 31, 2012 hmm basic porting 101 tells us that for low end and midrange the boost ports are mostly for broading the powerband out.. BUT they can also hlep a drag motor in a way with some differnt angling.. IF you really really really think about what possibly might be going on in there..... so yea big ass CC motor thats got a very narrow actual powerband in the upper rpm limit of the rotating assembly is probably not going to see an improvement from boost ports escpecially one that is blowing the wrong direction.. the ports in the sleeve im not sure what to think about that.. i rember seeing them from jims old oem cylinders but never really seen a before and after effect shown on a dyno.. whats funny to me on your cylinders is how rough they look and how they seem ( to you) to run pretty good... you better start buying some rings and pistons. bet its going to eat them alive. already looks like the top of the port is getting beat up.. yea everyone needs a starting point and if your tired of paying for the work adn dont mind spending about 5 times what a port job would cost on proper tooling and time for technique building then for all means go for it!! there have been many a blown up motor in trying to figure out what "works" and truthfully with out a dyno you cannot really push motor's to their absolute max. only thing you can do is your own "theriories and real world" testing.. Bro, you missing the point. I have a built motor from hJR on my bike! All top of the line stuff from custom cut domes in a chariot head down to the Rudy Kurtz tranny in the bottom. These Lil jugs were sittn on the shelf needing a fresh bore, new pistons, and rings. We just decided to look at several reputable proven port jobs, measure, mic, and cut to see if we could make them run with our pro port job bikes. When I say they "run good" or whatever u are trying to say by "to me" . Trust me bro I know what runs and what don't. These cylinders in there current state on a 54 mm stroke got beat by a bike length at 300 ft in the sand by my 4mil HJR motor on alky. If you are familiar with Kevin Herr you would know that we didn't do too bad. Maybe on a fresh bore, exaust polished, good set of drag pipes (we ran with CPI BB inframes), lil more timing, custom domes (proper squish) ...they may run just as good or better "to me". Lol. One more thing this Lil build isnt a "how to" or what the normal guy should do by any means. Ive been messing with these bikes for 12 years or so, and as stated my Lil 391 motor is a proven winner at the track so basing it off that bike "to me" is as good as a dyno. I'm not guessing it's performance I'm proving it. If you got time, money, and parts to spare do what u enjoy! Wrench on something! It's what we do, it's what I like! Don't knock me for that... Disclaimer: If you have 1 set of jugs and want a runner don't try this at home you will most likely fail and ruin a 250 dollars on a set of stock jugs. ( dinner and a movie) Quote Link to comment Share on other sites More sharing options...
Pasi S. Posted February 2, 2012 Report Share Posted February 2, 2012 Bro, you missing the point. I have a built motor from hJR on my bike! All top of the line stuff from custom cut domes in a chariot head down to the Rudy Kurtz tranny in the bottom. These Lil jugs were sittn on the shelf needing a fresh bore, new pistons, and rings. We just decided to look at several reputable proven port jobs, measure, mic, and cut to see if we could make them run with our pro port job bikes. When I say they "run good" or whatever u are trying to say by "to me" . Trust me bro I know what runs and what don't. These cylinders in there current state on a 54 mm stroke got beat by a bike length at 300 ft in the sand by my 4mil HJR motor on alky. If you are familiar with Kevin Herr you would know that we didn't do too bad. Maybe on a fresh bore, exaust polished, good set of drag pipes (we ran with CPI BB inframes), lil more timing, custom domes (proper squish) ...they may run just as good or better "to me". Lol. One more thing this Lil build isnt a "how to" or what the normal guy should do by any means. Ive been messing with these bikes for 12 years or so, and as stated my Lil 391 motor is a proven winner at the track so basing it off that bike "to me" is as good as a dyno. I'm not guessing it's performance I'm proving it. If you got time, money, and parts to spare do what u enjoy! Wrench on something! It's what we do, it's what I like! Don't knock me for that... Disclaimer: If you have 1 set of jugs and want a runner don't try this at home you will most likely fail and ruin a 250 dollars on a set of stock jugs. ( dinner and a movie) Quote Link to comment Share on other sites More sharing options...
KEVSWS6 Posted February 8, 2012 Report Share Posted February 8, 2012 Did you sell the HJR stock 4 mil jugs? Did I just send you a drag ported 421? Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted February 13, 2012 Report Share Posted February 13, 2012 With your exhaust that wide on the bottom, is your piston skirt going to be big enough to keep the mixture sealed in the case, when the piston is ATDC? Quote Link to comment Share on other sites More sharing options...
sstaton1983 Posted February 13, 2012 Report Share Posted February 13, 2012 (edited) With your exhaust that wide on the bottom, is your piston skirt going to be big enough to keep the mixture sealed in the case, when the piston is ATDC? Edited February 13, 2012 by sstaton1983 Quote Link to comment Share on other sites More sharing options...
sstaton1983 Posted February 13, 2012 Report Share Posted February 13, 2012 im sure he scribed the width of the port on the piston .thats what i do to make sure i dont go to wide. Quote Link to comment Share on other sites More sharing options...
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