Phazer to Vmax Carb Conversion...experts inside please!

thats a huge jet for a phazer, the nozzle/needle affect 1/4-3/4 throttle, I wonder if the pipe is correct. I ended putting an AEM wideband on my phazer to varify the air/fuel ratio at different throttle positions, I run at about 13-14 at idle, 12-13 in the middle and 11.5-12.4 wide open. the wideband has been a god send for dialing in the carbs
 

Extreme Elmo said:
thats a huge jet for a phazer, the nozzle/needle affect 1/4-3/4 throttle, I wonder if the pipe is correct. I ended putting an AEM wideband on my phazer to varify the air/fuel ratio at different throttle positions, I run at about 13-14 at idle, 12-13 in the middle and 11.5-12.4 wide open. the wideband has been a god send for dialing in the carbs
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I found out the hard way about nozzle and needle function. Elmo is correct but the over lap between the nozzle and needle is around 3/8ish throttle and depending how rich one or the other is, it will mask the over lap and its effectiveness will move up or down throttle accordingly. Same with pilot/nozzle.
Too large of a nozzle will make you think you have an overly rich pilot. The needle will do the same to some degree as well.
In other words, if you have a great idling sled, with reasonable turns on the fuel screw and it responds well comming off the bottom, then the next piece to tune would be the needle.
 
Hey COB, that is one of the few correct diagrams I have seen. There are alot out there with the needle and nozzle swapped.
 
I tried finding the one I was refering to and ofcourse I cant find it. I had a cataloge a while back with the needle/jet swap and I remember I was getting frustrated trying to tune my exciter, then later realized I was tuning the wrong piece due to the diagram pointing me at the wrong piece.
 
found a part of the problem why i was needing so rich main jet.
The bender racing pipe i had was for a exciter 570...

So i found a DG pipe last week. Installed it this weekend.
With the TM38 flatslides from a 1995 V-max 600. needle clip on the top with one shim under. Stock pilot jet (52.50) air screw 2 turns out.
Try 156.3 main, 150, 147.5 and now 143.8 and i always have a strange rattling sound every time i snap the trottle to WOT.
but the better for the moment is the 143.8...

When it make this sound, i lost power. Not able to gain rpm higher than 6000rpm.
I made some plug shop at 1/2 trottle to verify the needle. It is a nice dark brown.
Not able to do some WOT plug shop since the engine realy loose power and make this strange sound.
I ride at around 1500 to 2000Ft altitude at -20 deg Celsius

NOTE: The airbox is not gutted... Maybe i will try this next time.
Any recommendation on the airbox with the flatslide?
 
I came across this same rattling on my 87 phazer when I installed a dg on it. The rattling started about a few days later. Checked compression when it started rattling and was 125 pto and 125 mag. Then last season it would pass the 6000 rpm mark and started hesitating when I would hit the throttle. Did another compression test and the pto cylinder was 90 and mag was still 125.
Don't know what caused it or what it looks like because I haven't tore into it yet. I wonder if anyone else has had this problem with the dg exhaust?
 
I have the detonation rattle also, mine happens at 1/4 throttle under light load, my wideband indicated its really lean there 15.+ afr, and it's good everywhere else. I am going to lift the needle a little and drop my main jet one size. I will report back when I try this.
 
so I have settled on 50pilot, needle with both plastic washers under clip and clip in the middle, a 148.8 main....no detonation and it runs really strong, I am pretty happy with the DG pipe
 
kevfort19 said:
Thanks for your answer,

Will try this setting this week-end.

Have change your primary clutch setting?
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yes, I am dialing it in right now, so far stock springs (mines a 96) tightened up the secondary and change the weights to 8AB with aluminum rivets in the holes
 
Got them yesterday and physicaly they will fit. Now to install them and test is the jetting is right. I will start with the exciter jetting and work from there (I already have a pipe)
 
For those who talk about a gutted airbox, you mean taking out the entire bowels from it? You open it and remove all the partitions inside?
 
Yes, I removed the metal plate, and cut the baffle behind it out and removed the tube in the bottom with the holes in it
 
just for info, VM38's from the exciter fit right, jetting seems to be goos, just need to adjust the pilot screws a bit
 
I have a little feedback for you guys. I gutted the airbox and WOW it had totally eliminated the WOT boging that i had. I endend with the pilot 52.5 stock from the vmax ( in waiting for the 50). Main is 147.3 with needle clip in the middle. The engine have a very good throttle response. Just need a little clutching adjustement in the primary clutch. I will probably change de spring.
Im at 2000ft from sea level. Temp at around -15 celsius
Dont forget to gutt the airbox, i had try a 140 ans it was too rich en had a poor throttle response.
 
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