Thread: Porting (cases)
04-04-2010, 11:14 PM #1
I'am also planning on porting in the near future, i notice some guys just port the cylinders other do cyliders and cases as well, i've read a couple of threads back from 2007 and it was very contradicting. What are your thoughts on this issue? if it's just the jugs how much $ is this going for.
04-05-2010, 07:40 AM #2
04-05-2010, 08:11 AM #3
Cylinder porting is where the biggest gains come from, case porting is a compliment to this.
04-05-2010, 08:27 AM #4
For the most part case porting is done on race craft..??
Though on my GP1200 i ported the cases myself.. the bottom end hit is very strong..
It would be a hard thing to measure.. since its not exactly something that can be bolted in and tested half an hour later on the same day..??
Also it would be highly unlikely anyone would completely disassemble their entire motor..
Port the cases ONLY then reassemble to see if it added any MPH..
As a final thought my own GPR does have some major case porting done to it..
Waiting on the weather to improve before any results can be posted..
As for the costs involved with cylinder porting..
There are guys on the forum with 100% recommendations
A couple that come to mind are, Lowell (LHorning,. www.2-Stroke-Porting.com) and Kevin (water woody,. www.wcporting.com)
Hit them up with a PM or check out their web sites for info
Good luck with what ever you decide..
04-05-2010, 07:22 PM #5
Case porting on a 65u is def needed. It will give you a lot more bottom end and snap. The 1200 and 1300 r are a lot different. If you port then and add case volume it can hurt performance. These cases are much bigger and hate lower case pressure. So if you are going to port a set of cases be sure to add material to prevent a drop in case pressure. This will allow you to keep the the same case volume too. Just a couple things to think about.
04-05-2010, 08:05 PM #6
- Join Date
- Apr 2006
- South MS
Yes, I've even heard of stuffing the cases on other 2-strokes to decrease volume.
04-05-2010, 09:04 PM #7
04-05-2010, 09:08 PM #8
- Join Date
- Apr 2006
- South MS
I think its where they fill in the big spaces inside the case. I'm guessing it makes it more responsive. An outboard racer was telling me about it.
From what I've heard there is little to no gain in porting the cases on a GPR. Not top speed anyways.
04-05-2010, 09:34 PM #9
[UOTE=Ronn25;1383543]I think its where they fill in the big spaces inside the case. I'm guessing it makes it more responsive. An outboard racer was telling me about it.
From what I've heard there is little to no gain in porting the cases on a GPR. Not top speed anyways.[/QUOTE]
Thank you Ronn, always been very helpfull and given exellent advice. In all my stages of mods (Seems like you been there and done that). . I've hear that as well, I guess i just want to do it the right way, every one i've spoken to agrees on one thing ( cases is not going to be a noticeable difference, not needed). thanks everyone
04-05-2010, 09:36 PM #10
What some do is fill under the reeds with bloenza. Spelling might be off. It is a very expensive resin that is not metal based. This allows for no damage if it would ever come loose and ingested by the piston and cyl. I used it and it works great.
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