Having carb troubles

[Garagegoon]

Ok... Im new to the whole Z world. Just purchased a 72 with a holly 4 barrel carb mounted on it... Carb is junk and am lookin for another to replace but cant find one in my area small enough. I was told this one was 390 cfm...Anyone have any ideas or suggestions?

[Bonzi Lon]

Welcome, I'm just a half hour west of you. From my understanding the 390 cfm is about the right size for these engines. Most owners have the round top SU carbs that came with the 70 to 72 Z's as opposed to the flat tops of the 73 models. When running right you will LOVE this car. Again, welcome and a PM has been sent.

Bonzi Lon

[Fun_in_my_z]

I would get a manifold and a set of round top SU carbs and put on it.

[BR-Z]

I had a crappy old conversion too. I just did as above - got a used roundtop set of SU's from a member here. Watched the Z-therapy SU video and fiddled just like they tell you to on the video, bolted them on and THEY WORK GREAT!

Of course it depends on the condition of the used set you get...

The Z-therapy "reman" service is yet another step up in sweetness, but my rationale was, try the carbs "as is" first - and I'm very happy with the performance. Maybe I'll do the Z-therapy service later. If you've got the $$ and want to fool with it just once, I'm convinced you wouldn't regret it - look at all the happy customers' testimonials here!

Either way, one thing's for sure, SU's are good carbs for this car!

[sblake01]

If you're looking for the Holley 390 cfm, you wan the model 4160. Single inlet, electric choke, vacuum secondaries. The choke hook up is easy, just a hot wire to 'ign. on', but you'll still have to play with the jets to get it right since they are universal carbs. This is the one. I'm not endorsing 4bbl carbs on L6 engines, however.