LPG conversion of 89' SBC 350 TBI, recommendations

[storm]

Hi Ivo,
This is a very sensitive mixer to adjustments. Even 1/8 of a turn can cause dramatic mixture changes. If the mixer you received is new I would suggest you count the turns to bottom the existing gas valve and then set the new V2-50 in the same location. If not adjust the valve 1 & 3/4 turns up from the bottom. By the way when you take out the gas valve the spring on the shaft will appear to have a kink in it. This is normal. It keeps the spring and valve in place while replacing them in the mixer.

You will know right away if the setting is close when you try to start it. The engine will fire and start within a few seconds. If that does not happen you will have to have help and fuss with the setting to start it. Have a helper turn the engine over with the gas at half throttle. Turn the gas valve adjustment in or out until the engine starts. Keep the engine at a high idle, about 2000 RPM. Turn the adjustment so the rpm increases. As the RPM increases have the helper slowly release the throttle until you can get the engine to idle. Now you can do your proper adjustments.

There should really be a thanks or reputation type option on this site. If there was I would give you one for this post.

[rack]

Hi Ivo,
This is a very sensitive mixer to adjustments. Even 1/8 of a turn can cause dramatic mixture changes. If the mixer you received is new I would suggest you count the turns to bottom the existing gas valve and then set the new V2-50 in the same location. If not adjust the valve 1 & 3/4 turns up from the bottom. By the way when you take out the gas valve the spring on the shaft will appear to have a kink in it. This is normal. It keeps the spring and valve in place while replacing them in the mixer.

You will know right away if the setting is close when you try to start it. The engine will fire and start within a few seconds. If that does not happen you will have to have help and fuss with the setting to start it. Have a helper turn the engine over with the gas at half throttle. Turn the gas valve adjustment in or out until the engine starts. Keep the engine at a high idle, about 2000 RPM. Turn the adjustment so the rpm increases. As the RPM increases have the helper slowly release the throttle until you can get the engine to idle. Now you can do your proper adjustments.

Hi Rand,
I am pretty far from starting the engine I will start installing LPG when the weather here get a little warmer I don't have garage, big enough to accommodate this Suburban
I will put this valve in new mixer, so I will follow your advise and report back.

I really appreciate your help!
Best regards,
Ivo

[rack]

Today I had the time to change valve in the mixer.
Unfortunately, the new mixer I have is generic, not Impco, so the valve is bigger for it.
The valve that is in the mixer is 16mm in diameter and 17mm long, the V2-50 is 17mm in diameter and 15 mm long, so it definitely won't go in it.
Fortunately, I have used original Impco CA300-50-70 which I was going to rebuild. I have no previous adjustment for it because I dissembled it without taking any notes.
I will adjust it when installed on the car.

The weather gets warmer here, and the project starts
I will keep posting what have been done so far.

Ivo