Hey all,

I'm rebuilding a used Holley 4160 carb for my 351w. Holley says that my main jets should be #64. The carb has #63 jets in it now. Can I start with them or do I need to get the #64 jets. Engine is stock 86 HO.

 

Yes, you can start with the 63's. Assuming that 4160 is a generic carb with no specific jetting, just average jetting for the average engine, someone has probably leaned it down some for your application.

 

Thanks Gary. My truck came with the 4180 but it needed parts so i just picked up this 4160 to use.

 

It'll work, but might take some tuning. The box-stock 4160 I have was quite rich on Rusty's M. So the 63's might be a good starting point.

 

Alright! Gary, what size jets did you end up with? The guy i bought it from said it ran rich on a chevy 350.

 

I didn't rejet it, but switched to an Edelbrock that was much closer out of the box. And then I leaned it 4%.

 

That's cheating! :P

 

Lol! Yes, but it sure worked. The Holley, again box-stock, was really rich at idle and somewhat rich at cruise. The 1406 Eddy got the idle right where it should be and got the cruise pretty close. Then, with the wide-band AFR meter I tuned it the way I wanted it.

 

The stock cat no 1850 holleys I run have 66 jets stock on the primary, and that metering plate on the secondary. I have never had a problem with them on the 302's I run them on. I guess I could have leaned them out some, but they never ran "rich" that I ever noticed.

If that is a used carb you should put a kit in it. And while you have it apart, run a file across the main body where the metering plate bolts to the front. You will probably find some warpage and you need to get this out of it. It will run great after that.

 

The surface you need to check is in the picture below, to the right of the number 12. You will probably find the 4 threaded holes on the corners higher than the rest of the surface. This gives you leaks on all those little holes in the middle.

 

Thanks Dave, I have it apart right now for a rebuild. I guess I'll run a file over it before I reassemble it then.

Can I just snug the float bowl bolts up or is there a torque spec I need to follow? I don't have an inch pound torque wrench.

 

Just tighten in a chris-cross pattern, snug then an extra half turn, make sure you use your blow gun and clean out all the vent holes that go into the air horn. Alot of people forget about them, and you get a siphon effect, you need gravity to help push fuel thru the jets and idle mixture passages.