Holley Carb Question?????? (Long Winded)

[72-LT1]

Hey guys, just a question on the original carb on these cars. I sent the original carb off to Holley for their restoration repair.

The car was stumbling and backfiring through carb and all around running like crap before I sent it off. I put on a 4150 750CFM, mech sec, that I borrowed off a buddy, while they had the carb. The car ran great using this carb no stumbling or anything. The timing and everything is pretty dialed in, and it was running good.

Now I reinstall the original carb (it looks nice), but it really is not running good until it warms up for a while. On initial start up it cranks for what seems a little to long, maybe 10sec, and then it will start and stall when I give it gas. Then on the second start it will run OK, after feathering the accel a few times. It will chug and such on the road until you run it for about 10min.

I was thinking the choke was not working right, it stays open when it cools down, and then closes up when I hit the accel, then it opens up about ¼” when it starts running until it gets warm and opens up all the way.

The fuel bowls are full right up to the holes so I think that’s good and I think the choke is doing its thing, so does anyone have any ides as to why it takes so long to run well?

Thanks in advance

Rob

 

[motorman]

Hey guys, just a question on the original carb on these cars. I sent the original carb off to Holley for their restoration repair.

The car was stumbling and backfiring through carb and all around running like crap before I sent it off. I put on a 4150 750CFM, mech sec, that I borrowed off a buddy, while they had the carb. The car ran great using this carb no stumbling or anything. The timing and everything is pretty dialed in, and it was running good.

Now I reinstall the original carb (it looks nice), but it really is not running good until it warms up for a while. On initial start up it cranks for what seems a little to long, maybe 10sec, and then it will start and stall when I give it gas. Then on the second start it will run OK, after feathering the accel a few times. It will chug and such on the road until you run it for about 10min.

I was thinking the choke was not working right, it stays open when it cools down, and then closes up when I hit the accel, then it opens up about ¼” when it starts running until it gets warm and opens up all the way.

The fuel bowls are full right up to the holes so I think that’s good and I think the choke is doing its thing, so does anyone have any ides as to why it takes so long to run well?

. sounds like your rebuilder may not run the carb on a engine before senting it back to you. it could be they did not check for warpage on the gasket surfaces and you may have a fuel leak thru. also 72 carbs were leaned out for emmissions so the carb you borrowed is much richer than you stock carb. i would try and richen up the primary a couple of steps.

 

[72-LT1]

I will try and richen it up a bit. I dont think the fuel bowls are leaking, because before I started it up today I checked the fuel level in both bowls and they were up to the holes like the specs said.

As far as them not checking for tolarances and warpage, I sure would like to get a few more responses and tips before I call Holley and ***** about it. For the price of the rehab I expected them to be the most knowledgable and experienced since they produced the damn thing.

Thanks for answer

 

[72-LT1]

The guy at Holley said they test tolarances and warpage, and since it seems to run good after its warmed up it might be the divore choke spring that connects to choke and intake manifold.

I think I'll go get one at vette parts, its only $15, and if thats not it he already gave me am RMA number to send the carb back.

Mike at vette products also mentioned a choke riser or something ???? that supplies vacume to choke? anyone know about these?

Thanks