Carburator base plate replacement

[Lemans Blue 69]

I own a 1969, manual trans, L46, 350 w/350 hp with no air. One year ago the throttle would not settle down to idle unless I tap the accelerator. Lars gave me a tip to attached the return spring forward to the carburator and it worked like a charm. Re built the engine with all new parts these past 3 months and the carb again has idle down issues. It is the original carb and I want to keep it. When I took carb off the engine, and removed the base plate, I could feel resistance before the throttle plates fully closed. The plates were actually bent. Removed them and put them in a press to flatten them. Reinstalled them and the throttle on just the base plate seemed pretty smooth with hardly any detectable resistance. Put it all back together and once the engine was hot, I could feel the resistance.

Bottom line, I want to replace the bottom base plate only which contains both the primary and secondary plates with the best brand new base plate for my carburator. Any suggestions?

 

[Rod75]

I own a 1969, manual trans, L46, 350 w/350 hp with no air. One year ago the throttle would not settle down to idle unless I tap the accelerator. Lars gave me a tip to attached the return spring forward to the carburator and it worked like a charm. Re built the engine with all new parts these past 3 months and the carb again has idle down issues. It is the original carb and I want to keep it. When I took carb off the engine, and removed the base plate, I could feel resistance before the throttle plates fully closed. The plates were actually bent. Removed them and put them in a press to flatten them. Reinstalled them and the throttle on just the base plate seemed pretty smooth with hardly any detectable resistance. Put it all back together and once the engine was hot, I could feel the resistance.

Bottom line, I want to replace the bottom base plate only which contains both the primary and secondary plates with the best brand new base plate for my carburator. Any suggestions?

To the best of my knowledge, new Q-jet's are no longer produced. I think Edelbrock was the last producer. There are quite a few parts suppliers out there tho.
Sounds like you want good original quality. With that in mind, I would send the orig base plate out for a quality rebuild. They can machine and install new shaft bushings, shaft and butterflies. That should remedy your problem.
I would also have them check it for warpage.
I don't have a company to recommend for you, as I have a friend do all my custom machine work.
You may want to contact Lars Grimsrud here on the forum, under the user name Lars. He's known for in-depth Q-jet knowledge.
Good Luck!

 

[Lemans Blue 69]

To the best of my knowledge, new Q-jet's are no longer produced. I think Edelbrock was the last producer. There are quite a few parts suppliers out there tho.
Sounds like you want good original quality. With that in mind, I would send the orig base plate out for a quality rebuild. They can machine and install new shaft bushings, shaft and butterflies. That should remedy your problem.
I would also have them check it for warpage.
I don't have a company to recommend for you, as I have a friend do all my custom machine work.
You may want to contact Lars Grimsrud here on the forum, under the user name Lars. He's known for in-depth Q-jet knowledge.
Good Luck!

I know of Lars and he knows me. Believe we have an understanding even though it has been awhile since we communicated. Don't want to tie my car down any longer. Summer is short in Massachusetts and I'm willing to purchase a quality rebuilt base that will cure my problem.

Just want to know if it is available and if Lars is monitoring this post, maybe he can direct me. I read that he no longer rebuilds carbs.

Thank you for the reply

 

[lars]

You're not going to find a new baseplate - you have to rebuild what you have or swap it out for another used one. If you send the carb or the baseplate to me, I can do the setup for you.
Lars