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cub porting question.

3646 Views 17 Replies 11 Participants Last post by  Kawiking
I have a 7mil cub that just has a clean up port on it and I was wondering how hard would it be to go back and do a drag port?? Also would I see a significant gain from it??
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ive heard the most u get is 7 hp out of a drag port on cubs......
with nate on and others they will be able to tell you from a builders prespective but Kim told me between 2-5hp increese with the difference in porting.the clean up is just trying to get the flashings and all smooth .
QUOTE (phatboyz @ Jun 2 2008, 05:36 PM) index.php?act=findpost&pid=1726with nate on and others they will be able to tell you from a builders prespective but Kim told me between 2-5hp increese with the difference in porting.the clean up is just trying to get the flashings and all smooth .
Cleaned up 421 Cubs on alky will make around 91-93HP on alky depending on the state of tune(83-87 on gas). Weve made 106 on gas and 110+ on alky with drag ported versions as other builders have done as well. Even better gains on 10 mills on clean-up vs. drag ports...Jim
But what im asking is can you report through the plating??
I assumed it would be somewhat like stock cylinders, do the porting then they get replated. I'm not 100% on the nikasil stuff though.
QUOTE (okbeast @ Jun 2 2008, 09:54 PM) index.php?act=findpost&pid=1742I assumed it would be somewhat like stock cylinders, do the porting then they get replated. I'm not 100% on the nikasil stuff though.

The nikasil plating is very hard to cut through. If the cylinder has been previously plated. And then you send it for porting ? They have to cut through it, to do the porting. When finished it is best to get it replated. The porting on a cub is cheaper if it has never been plated, or it has been sent in to be stripped before you get it ported.
QUOTE (duecebanshees @ Jun 2 2008, 08:10 PM) index.php?act=findpost&pid=1745When finished it is best to get it replated.
Word.
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We port through the plating all the time, I get our cubs already plated so they don't have to be shipped back and forth across the country so many times, and so a customer can walk in and order an engine without waiting so long. It takes a diamond bit, a lot of patience, and you hope you dont slip too bad.
Ditto .. you can sucessfuly port on plated cylinders but it is not for the beginner ,you must take your time use the right sppeds lubricant pressure and dimaond tooling ,the big fear is chipping/flaking that where a careful hand and know -how comes into play
QUOTE (FLOTEK @ Jun 4 2008, 08:31 PM) index.php?act=findpost&pid=1901Ditto .. you can sucessfuly port on plated cylinders but it is not for the beginner ,you must take your time use the right sppeds lubricant pressure and dimaond tooling ,the big fear is chipping/flaking that where a careful hand and know -how comes into play
And above all.....the quality of the plating to begin with....all the above skills can be useless if the plating is substandard....Jim
i have ported cubs and cheetas with plating.. you do have to be carefull on the transfers..

there really shouldnt be much more cost from a drag port from what you have now there wont be a LOT of work thats done in there maybe raise the exhaust and match it all up with a degree wheel or something..
QUOTE (camatv @ Jun 4 2008, 11:28 PM) index.php?act=findpost&pid=1910i have ported cubs and cheetas with plating.. you do have to be carefull on the transfers..

there really shouldnt be much more cost from a drag port from what you have now there wont be a LOT of work thats done in there maybe raise the exhaust and match it all up with a degree wheel or something..
Really depends on your performance goals.....if you want to run with or outrun the fastest Cubs being built, extensive work is involved.....Jim
do u do aalot of drag ports,jim ?
QUOTE (kawiking @ Jun 5 2008, 05:04 AM) index.php?act=findpost&pid=1934do u do aalot of drag ports,jim ?
6 cubs ,5 OEM drag engines waiting to be built currently along with all the typical duner and woods stuff I normally get.....seems my business has shifted more towards drag engines over the last couple of years...Jim
QUOTE (BlznOkie @ Jun 2 2008, 02:45 PM) index.php?act=findpost&pid=1721I have a 7mil cub that just has a clean up port on it and I was wondering how hard would it be to go back and do a drag port?? Also would I see a significant gain from it??
A good drag ported setup is worth about 10-15hp an a 7mm cub. Porting through the nik is no problem for the competent porter.
jim.. when ever i heard "passion racing" i always thought of drag motors... i hear alot of good things about u and ur work.. keep it up !!
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