I'm really tired of my Edelbrock Qjet and all the problems I've had with it, so I'm debating on putting a 750 DP with mechanical secondaries on my car. The only concern I had was the fact that I have an auto w/2800 stall and I hear a lot of people say you should go vacuum secondaries on autos. Will I have any problems if I go with mechanical on an auto car?

Josh, we need to know a lot more about your 383 in order to give you the right advice. What cam, compression, heads, intake etc. LukesVette2008-06-15 19:47:49

Sure. neuroclast2008-06-15 20:05:18

I went through some issues with a Edelbrock made Q Jet a couple years ago. They are good carbs for stock or very mild engines. Anything built on the "hot side", they aren't very good. The reason being is that the metering rods used in their Q-jet carbs are "truck" rods. They will put your engine in a lean condition at wide open throttle. I learned this through dyno runs and speaking with a gentleman named Lars on the other vette forum who has a lot of experience with Q-jets . Sarge812008-06-16 07:21:07

A DP is gonna bog it down on take-off if ya nail it. Stick with a Vac sec.
I ain't a fan of Holleys on anything short of an all-out racer, but that's just me. A well tuned REAL Q-jet will outperform a Holly on the street, imho.

I completely agree with Joel's comments.  A double pumper is great for drag racing, but sluggish on the street, unless you have a much bigger, more radical engine.  It is hard to beat an original Q-jet when rebuilt and properly recalibrated for your engine.  If you set against the Q-Jet, I would look first at the new Barry Grant street carbs.

Larry

the edlebrock will run with the 383 just fine. A #1406   750 w/vac secondaries. It WILL  need to be calibrated by someone that knows how to tune hp engines. I had a hell of at time with mine until it was done right. THe distributor need callibration as well.

I am running 93, but it's not working well.  It pings like crazy when under load at low rpms. I'm thinking about trying a thicker head gasket to see if it will help any :(

i had exactly the same problem. the head gasket will not solve your problem. if indeed you at  greater than 11:1 pump fuel going to be an issue. try some racing fuel to bring up your octane and see what happens. your symtoms  are identical to mine were. and with out the adjustments it will continue. I had 5 different carbs on mine so that isn`t the problem. it`s the tune. good luck.