Hi everyone, I just finished rebuilding a 2.2-liter engine on my 1971 Porsche 911T with Weber carburetors. The engine is still breaking in and runs perfectly up to 4,000 RPM, but then it stumbles and won’t go past that point under load.
However, if I press the clutch and rev it in neutral, it reaches 7,000 RPM without any issues.

New Spark Plus

Distributor is electronic ( but don't know how to measures degrees or use a lamp

I did not have the syncrometer ( mat be could be the air/ mixture )

May be a carbs clean could help ( in that case I will new a kit of gaskets jets etc ? )

It seems to me is an ignition or electronic problem , Thanks and good ride !
Ralph

Hi everyone, I just finished rebuilding a 2.2-liter engine on my 1971 Porsche 911T with Weber carburetors. The engine is still breaking in and runs perfectly up to 4,000 RPM, but then it stumbles and won’t go past that point under load.
However, if I press the clutch and rev it in neutral, it reaches 7,000 RPM without any issues.

New Spark Plus

Distributor is electronic ( but don't know how to measures degrees or use a lamp

I did not have the syncrometer ( mat be could be the air/ mixture )

May be a carbs clean could help ( in that case I will new a kit of gaskets jets etc ? )

It seems to me is an ignition or electronic problem , Thanks and good ride !
Ralph

Dear Ralph, your engine is a mess. Please start a new thread so we can work through your problems one by one..

Ralph, I don't know the exact rules any longer but you may need a few more posts to the forum before you can start a new thread. Easy to do.

Hope this Helps! It's what I run.
 

Can someone explain the advantages of the drop from 6 degrees at 500 RPM to 3 degrees at 800 RPM? Does it help with start up and idle? Also, why not hit the max advance of 35 at 6000?

It should help with cold starts, idle is farther up. You can go up to 35, doesn’t mean that you have to. You should know your AFR’s at redline before advancing too much.