I have a OEM carb off a '01 Scrambler 400. I would like to put it on my son's 2000 TrailBlazer.

The questions I have are:

1. What is a good point to start out jetting at (main, pilot, needle)?. I run the TB with the snorkle removed and a Trail pipe. I live in Oklahoma and our feet above sea level is 1400, temp in winter 0-50 degrees usually.

2. Does this change the oil injection ratio? In other words should I remove the oil injection or can I leave it? I prefer to leave it because with my 12 year son, he can gas it and go, but will it no longer mix accurately?

3. Is this too much carb for the 250 engine. Will it bog at low range, or not peform well in the mid or high range?

4. If it does improve, where are the improvements most noticed and where are things that aren't as good as with the stock TB carb?

Mike Chero, Rick Ritter recommended you and said you have done this. Would you mind sharing your experiences? Also, anyone else please chime in with your experiences too.

Thanks in advance.

Chunky

 

Chunky5678,

Not at all, I'd be glad to help!

If you have a Clymer manual, they already have the proper jetting in it for the "ill fated" Cyclone. The Cyclone was basically a hopped up 250 motor that was put into a chasis that was a warmed over three wheeler chasis. It only lasted one year (1987) and it was gone.

Here's what I ended up with:

Pilot jet- 40

Needle jet- 0-4 from the 250 carb.

Jet needle- 6CEY6-3 from the 400

Main jet- 200

Now if you went with a U.F.O. (Ultimate Flow Optimizer) the jetting would be:

The richest UFO

Pilot jet- 15

Needle jet- O-4

Jet needle- 6CEY6-3

Main Jet-210

I never messed with the oil injection at all and the quad is still running a stock piston and bore for two years since I went to the larger carb. Also it starts up VERY reliably in cold weather.

Hope this helps!