marshall-no

I've just installed a new 350 rocket in my 70 convertible with the following performance upgrades and was looking for a better carburetor choice.



Specs:
350 long block core from Napa
Hedman Exhaust Headers (very tight fit beware)
New alum. water pump - Mondello.
New Edlebrock 3711 performer intake manifold- Mondello
New adjustable valvetrain – Mondello
New Hyd. Cam Jm18-20, .488 IN, .496EX, 260/266 duration- Mondello
New JM 830 Annular Carburetor (vacuum secondary) – Mondello
all except headers Mondello recommended


The last recommendation I think was flawed and I’m thinking its too much CFM for such a heavy car with stock gears. (of which I’m not sure- highway cruising) I do want to change to 4.11 gearing. It's got a Th350 trans with a shift kit too.


Any thoughts?


thanks in advance

The_Jeremiah

Nothing beats a Quadrajet. They are just hard to find. I myself havent had good experience with the holley rebuild service, but maybe you will. Other than that, i would recommend like a 650 holley. They are EASY to keep tuned properly. However im not entirely sure what will work the best.

Redog

I'd go a bit higher with that set up. Maybe a 750

J-(Chicago)

Holley 650 double pumper.

captjim

Not busting chops here, but what heads are on that 350? Chances are it has VERY low compression, like in the 7.6 to 1 neighborhood. If that is the case (not saying it is, but I bet'cha it is) you are too aggressive on the cam, intake, gear, converter and carb. What heads are on it, 3A?

Warhead

WHOA big fella!!!
830m annular is WAAAAAAY too much for that engine.
350 long block core from NAPA tells us nothing about the engine, except it displaces 350 or so cubic inches.
The cam may be too big, depending on how engine was built, just like cap'n said.
Go big on the heads, and small on the cam instead.
A q-jet is the way to go. Not hard to find at all, out here. Make some calls.
Quit spending your money at Mondello's unless you like a ball hone up your exhaust pipe. You will get it in the end.
The problem is Joe is not there anymore.

Olds64

Quadrajet!

59-59-59

This is a GREAT carb if you want to stick your head under the hood to tune it every weekend. In my OPINION, you would be better off with an Edelbrock. I have bought new Edelbrock carbs in the past and havent touched them in years - set it once and forget it.

The_Jeremiah

Thats the exact one im buying tomorrow from schucks. They are having a 3-day 20% off sale on any single item over 100 bucks. So that 336 dollar carb just became like 268 bucks. Cant afford not too, considering every other parts store wants like 350 for the carb, and isnt doing the sale right now.

marshall-no

after trusting the advice I started to worry about the carb advice. The heads are no.8. as per 442.com. Thanks for the advice

Oldsguy

I have heard that about a million times and believe there is some truth to it. I have never personally had the pleasure to deal with Joe or the dis-pleasure to deal with Lyne (sp) or whomever it is running the show there now so I have no personal experience, just leave it at that.

marshall-no

I won't say anything bad about the service or parts - I just got some bad advice on the carb selection - really its my fault for not doing the research in advance.

thanks

Olds64

Oh man! MC DISS with CHEESE!

Edelbrocks are good too. I just like the kick in the pants feel of the secondaries opening on the spread bore Quadrajet. Tuned right the Quadrajet is very streetable. If it isn't done right it is a nightmare. I do agree that Edelbrocks are probably easier to set up.

#1CutlassSupreme

I went with a 650 Edelbrock Thunder series with the adjustable secondaries, but now I'm starting to have buyers remorse. I haven't had a chance to run it yet, but I was pretty fond of the big ole secondaries in my Q-Jet. Not to mention it was a good carb for around town driving.

If the Edelbrock doesn't give me significant gains, I'll probably rebuild the Q-Jet I have and put it back on.

Jokers69

Holley 600 on mine.. runs alright, don't like to give the Arabs too much $$