I bought a spare intake mani for my DS650 from Ebay the other day and it came in this morning. I went down to the shop and did a baseline flow on my SF600 and then went to work on the runners and removing that nasty hump on the top of the divider, smoothing out the walls and then applied a texture with the beadblaster. I seen a good 18% improvement. I then took the mani and Black Diamond blasted the exterior and applied some gloss black Polane to the exterior.


I no longer use any powder coating on my engine parts. I switched several years ago to a much better medium called Polane from Sherwin Williams, it is a two part urethane enamel that is far easier to apply and is far better suited for engine components. Far tougher than powder coating ever dreamed of being and is far easier to apply.

 

Looks nice. Did you do the porting for a stock carb or was it mated to a 45 or 48mm?

 

Port matched for the stock carb, but now with two mani's on hand, I can match the original to a TM45. Now I am looking for a spare head and a set of OMW-3's to build up.....

 

thats beautiful man!!! I was gonna pull my head and intake manifold off and do them at the same time... but I really dont need to pull the head off and don't want the headache.

Are you worried about the flow of your intake manifold being to much compared to stock for the head at all??? or just cleaning it out won't do that???

I'm not the porting genius, that's my uncle and cousins over at Air Flow Reasearch & development

 

With this being for use with the stock carb I didnt remove much material from the runners, just smoothed out the hump that is cast into the divider where the top bolt clearance divot seen on the outside is, sharpened the divider and cleaned up the casting marks, this gained 12% more flow, then after texturing the runners it went up to almost 18%. Alot of the guys up here always want their stuff ported and polished as they dont understand that polished intake runners actually slow the air mass down on a naturally aspirated engine and degrade fuel atomization(same reason there are many divots on a golfball). This should be within the capabilities of the stock carb/head to handle, we will see! LOL

On this engine I will only portmatch the heads ports to the mani, this can be done with the head and engine still installed in the bike. You stuff paper towells into the ports, then some plasticine clay(this seals the ports from debris entering the combustion chamber) and portmatch with a dremel/rotary tool and then lightly texture with 80 grit paper.

 

right on, thats what I was talking about in my last post. about the amount of airflow and N/A engines...you just described it better lol.

I appreciate the advice... and again your I M looks good man

 

I want to upgrade my crab on my ds650 baja to a TM48(kit just replacing the TM45 with the TM48) from Ron Woods racing. Will my stock head be able to handle this? if not what do i got to do? Also i have the CDI and exhaust system already.

 

Your head should be able to handle the TM48 fine from what I have read and seen, and give you plenty of room for future power adders like cam's and porting. I am new to the DS so I dont have alot of experience with the upgrades like some of the guys here, but have been working on engines and performance mods for many years.

 

And here is a pic of the one I just took off the DS.




And there was a difference after install of the ported mani, mostly in the top end, but I did have to lower the idle rpm as well.

 

Man that thing looks awesome. I've always been worried that I'll grind right through if I got rid of that hump. Is it close to breaking through?