I'm currently running the billet end cap and 175 main(Mikuni jet) and it's running great. Well, I installed the ported intake today and on the test ride I felt like there was not as much power as before. Then I went to climb some hills and it sputters on the bottom end. When it's at high RPM it seems to run fine. I'm thinking I need to go bigger on the main jet. What do you guys think?

 

I notice your signature says RWR ported intake. That intake has a very smooth finish, its more polished and sand blasted than ported. The smooth finish is probably where your problem is at. When fuel and air hit the intake the fuel is loosing its suspension at low rpm. What you get is a rush of air (sputter) when the fuel falls out of the mixture.



MrHorsepower
Horsepower Research

 

i have the rwr intake also(tm45) . should i rough it up a little with a die grinder

 

Eric.

Thanks for the info. What are your suggestions for roughing it up?

 

Well its kinda hard to explain on a keyboard. I use an electric diegrinder with variable speed and an assortment of carbide tools. Problems can definately arise if the "texture" of the manifold is not right. You will probably go faster with the stock manifold at this point.



MrHorsepower
Horsepower Research

 

When I first installed ported manifold I had a loss of power too, then I jetted up where I belonged for the added airflow and was very pleased with the gains.

 

I used a dremel with the the all purpose dremel connections pack (it has a aluminum roughing rock with the package) Worked great!

 

im going to have to try it...............has any one tried it before ruughing it up THEN roughing it up and seen what the difference was?

 

I just did mine today so i will let u know how it turns out. I ported my own intake and so far everything looks good. I will put it on probably tuesday or wed. of this week. when i get all of the rest of my stuff put on. You can take a look at my pics and get a idea of what it looks like. I will let u know how it turns out. This is just an example intake that i ported. If it turns out good i might start doing them for evrybody [img]i/expressions/face-icon-small-wink.gif[/img] Lance

 

yes bigshow a friend of mine ported his DS intake smooth, jetted accordingly, then roughed it up and got much more gain. smooth is bad, but what level of rough is best I do not know. of course, polished exhaust is good because it can help inhibit carbon buildup, but you need the atomization that a rough intake provides.

mine has a spiral made from putting a slot in a bolt shank, and slipping strips of 50 grit emery cloth in the slot, then mounting the shank in the die grinder and working it in and out of the manifold. is this better than leaving it even rougher from the cutter bit itself, or should it be a little smoother - say 80 grit? This I do not know, but what I do know is that the way it is yielded me enough extra power that it was easily noticable riding without any dyno proof.