Demon carb ? Tech
 

I have a 650cfm sea demon carb, it looks to have no Idle-Eze is this normal? I bought it used not sure how old.

Re: Demon carb ? Tech
 

Never mind I pulled the carb off and found the idle-eze but the hole was never drilled out under the stud..... Well I will drill it out and clean the carb up, I will try it out and get back... PS Looks like the base plate was newer then the carb body?????

Re: Demon carb ? Tech
 

It may be an older carburetor that someone installed a new baseplate on, but never modified the main body. You should be able to just drill out the stud hole and put the body back together.

Re: Demon carb ? Tech
 

Well I put it back on and the screw for the idle-eze was all the way in. I have it at about 2 turns out. Best vac is still around 6 to 7 at 700-750 rpms. I will change the power valve to a 3.5 and see were that puts me...... Thanks Kyle

Re: Demon carb ? Tech
 

3.5 is kinda low.......How did you come up with that?

Re: Demon carb ? Tech
 

This is what I have seen for powervalve posts / take vac and divide in half???? Is this right or not??? At low idle the vac realy dips low becouse of the cam..

(Kmiller, you said you put a 6.5 power valve in. you wrote you had 7.5-8.5 vaccum. if thats the case you should have a 3.5 power valve. you take your vac. reading and split it in half ,this a general rule of thumb.B.Miller)

Re: Demon carb ? Tech
 

With the vacuum that low a 3.5 should be about right. The vacuum seems a little low. You may need to check your initial timing. If it is too low it can cause the vacuum signal to be week.

Re: Demon carb ? Tech
 

A 3.5 power valve did the job!!!!!!!! I can now cruise down the Metro Canal with out fouling a plug in the first 30 seconds. Would a power valve change top end? I seem to have lost about 200-300rpm off top end??

Re: Demon carb ? Tech
 

The CORRECT way to choose a Power Valve is to hook up a vaccum gauge and note your readings at idle and at cruise....Select your power valve to be as close to 2.0 inches BELOW your lowest reading between the two...You don't want to go too lean......If Guessing that a 4.5 is probally your best bet (based on the 6.5 at idle). But you need to make sure that your cruise is not lower than 6.5........

BH

Re: Demon carb ? Tech
 

Why does everyone have different ideals my vac at idle is 6.5 the raceshop up the street said with that cam at 700 rpms that sound right. Some say 3.5 now 4.5??? Not sure maby I will have to play around.. Runs good now, it may have been the smooth water slowing me down....