Holley or Edelbrock?

[VAMP3D]

...or otherwise?

Chevy 383 vortec 425hp/450tq

I'm trying to figure out what my best bet will be. I'm ordering today.

[Morella]

I used to be a Quadrajet nut until I bought two new Edelbrock carbs, a Q-jet 1906 for the Cadillac 500, and a 1411 with the PROPER adapter for the Chrysler 440 (don't use an open adapter). Both of these carbs worked right out of the box, although I had to drive the 1411 around the block to get the float clean, then it stopped blowing black smoke. It's been my best friend for easy cold starting and high end flow ever since.

Most people just prefer the carburetor that they're used to working on, because that is the one that they will know how to get the best performance with.

-denise

[VAMP3D]

After talking to a ton of tech support folks, I/we settled on a Edelbrock Thunder series 650cfm. Ordered it today along with the stall convertor. Woohoo!

[BIGEVIL]

Most people just prefer the carburetor that they're used to working on, because that is the one that they will know how to get the best performance with.

Well said.

[Morella]

After talking to a ton of tech support folks, I/we settled on a Edelbrock Thunder series 650cfm. Ordered it today along with the stall convertor. Woohoo!

I'm sorry to say this, but I grit my teeth when people say "I'm putting in a stall convertor". What RPM is the stall? Or just "higher or lower than stock?"

What gears are you using? If you don't know, that's OK. I'm just wondering what you're building, and I don't know any of the history.

-denise

[VAMP3D]

Oh, sorry bout your teeth. 2300-2500 rpm. Stock gears for now, but I'll be beefing up the rear end soon. And once again, I'm open for suggestions. This is my first time dealing with a 4 wheel project so my experience starts now.

[Morella]

2300-2500 should do a nice job overcomng the stock gears for you. I made a mistake in not upgrading the torque converter on my 76 NYB. I was reading the chart wrong...the H.P. stall convertors are either 2600-2900 or 2100-2400, but I should have look at the stock converter, which is 1975-2275, and the FSM says that they lose 250-350 RPM over time. My brakes can only hold mine up to about 1400, even with the new and powerful booster.

Gears normally range from 4.11 for strip racing (not recommended for street use) to the low 2's for freeway cruising for good gas mileage (in cars that are designed to be greared that way. Usually the low 3's are a good setup for driving around town or wherever. Sometimes you just have to experiment. Some people will disagree with me. Be sure to listen to them too.

Good Luck

-denise

[BIGEVIL]

Some people will disagree with me. Be sure to listen to them too.

Denise make a great point again. Many coaches already have 3.55 or 3.73 gears already because of the car.
Actually, the rear end is pretty beefy from the factory. I have never damaged a rear in any of my coaches. My 1st hearse had a WELL built 500. Never a problem.
Any stall speed from 2200-3000 will be fine. The only time you will really notice it is if you accelerate hard from a standstill or are slowly climbing a steep grade. The biggest reason I suggest a converter to begin with, is the size of your camshaft. It will idle very lumpy and not run well at an idle with a low stall converter. This way the engine will not be bogged down at low rpm so it can idle with less drag from the transmission. Be sure to run an extra large cooler. Higher stall converters can generate a little more heat.

[Morella]

Yes, exactly. My hearse is geared correctly for its stock 500, probably mid 3's, and you can feel the torque come in right away. The cam on my Chrysler doesn't kick in until about 1800, and it feels like it has a low end problem because it is geared so that it takes a while to get up there. It really needs different gears, because I can't even top it out on the freeway in second gear. I'm already in the 80's. To cut through traffic in town, I have to go to first gear manually, which can take it easily up to 55 mph.

A gear vendors overdrive and different gears would be awesome, but way beyond my budget.

-denise