Thread: Holley Day, tuning issues

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Hiya!

I got a dillema in just what to do with carbeuration for my small block, Right now I have an Edelbrock 1401 Carter AFB look alike that I been tuning with a kit. I also have a Holly 600 cfm that I tuned once for the same engine.
The Holly worked great but used a lot of fuel, Jets are 66, secondary spring is in the middle range but worked fine for the engine at the time, I forgot what power valve I used but it has 2 6's or 9s, well, you get the picture.
First question is, which carb should I use? I know all of the Holly problems with leaking and power valves but I can fix the thing if it leaks, The plus is it was fast.
The Edelbrock has all the benifits of a trouble free carb but I still can't get it to scream like I want especially for the top end. It kinda flattens out at 70 or so.

The second question is what build should I use for either? I have a tuning kit for the Edelbrock springs, needles, jets. And I can lay hold of any Holly parts I want so I can just buy what I need.

The block is a 350 four bolt with double relief flat tops and 1.90 heads if I remember right. It has a cam but forgot the specs I'd say an RV equivelent, Stock crank timing, multi spark ignition, Dual plane Hi Rise manifold, ceramic headers with 2.1/2 inch pipes and Dynaflow type mufflers. Distributor is recurved, total timing about 40 if i'm adding right. Vaccum idles at 20. Tansmission is THM 350 with a stage 1 shift kit. Rear end is stock highway gears. back tires are 235 70R 15;s

Third question, On the Holly some smart fella says to leave the power valve out and use a plug and use bigger jets. Since I have 66, he says either use 67"s 68"s. Speed shop says OK for racing, bad for the street, Buddy who knows everything says BS. Who's right?

OK, so if it's the Holly, What jets an power valve should I use? Secondaries are vaccum.

If it's the Edelbrock I have installed what needles, springs and seats do I use. Secondaries on this are mechanical.

Both are 600 cfm' both with electric chokes.
What i'm looking for is faster acceleration from midrange to WOT.

Also, should I use a spacer between the carb and the manifold? if so, what thickness? Rigbht now i just have a thin plate with two gaskets just to cover the Quadrajet hole in the manifold.

So, can anyone help me on this? Holly or Edeibrock. The future is in your hands.

holley , 62-64 jets ,7.5 power valve, 50 cc acc pump.

if you enjoy buying gas and washing down your cylinders so it will smoke go ahead and plug the power valve off.

yea. need the power valve for the street. getting rid of it only benefits at WOT.

borrow a 750 vac sec. carb .. i think after you try it you mite get one .. my 351 loves it as did several 289s` i had ..

Hiyall,

So, I guess the Holly gets it. With the power valve.

I have a 750 Holly Vac secondary sitting at my local speed shop waiting to get sold for a measely 50 bucks. I figured it's just too big for my small block. If I had a big block I could see it but all that it did was burn gas an bog down.

62,64 jets? I'll try it but it might be too lean especially with the headers and exhaust.

OK one more pitch for that Edelbrock is there any way of making it go fast? Or is the Holly the only way to go for speed?

I'd go for a 1/2" spacer as the Holley doesn't transition well on a spread bore manifold and then I'd purchase a book like the one below.