I was looking up other cams on this board to see what other guys are running and I came across this post. I Believe it was written by ta performance. It gave me a little bit more optimism about my carburetor decision.
Quadrajets always get a bad rap because guys insist on just bolting on any Q-jet to their engine. Quadrajets were calibrated specifically for the engine they were meant for. Wanna put it on another engine? It likely will not run right. This applies especially if the engine is modified. There is a huge difference in the way a Q-jet feels on the street compared to a big Holley double pumper. I know, I have run them both. The Holley feels like it opens all up at once, makes you think you gained 50 HP. They burn a lot more fuel. For most, that is not a concern, and I understand that. I still prefer the Q-jet on the street. My engine runs great with the Q-jet/SP1.
Switching to a universal carb that has a fat low end makes every one think it’s running better too. Job isn’t complete.
He goes on to say that the quadrajet is an excellent carb but was most likely just old and worn out. Either way I find it funny/irritating that I was recommend by their sales staff to buy a 650 cfm. Even though they know the 350 likes a big carb.
Me either. The AFB clones are inferior carburetors compared to the Quadrajet. TA is in business to sell parts. They will gladly sell you what you want to buy. I can't fault them for that. The smaller carburetor properly tuned will give you better throttle response in everyday light to light performance, but it will be down on peak HP. I ran one of those carburetors on my first Buick a 72 Skylark 350. It ran OK, but I could never get it to be seamless everywhere. That counter weighted air valve on the secondary side is not adjustable. I couldn't tune out the slight bog and delay I would get when going to WOT from a low speed.
You would have to grind off part of the weights to get the secondaries to come on quicker at least that is what I read somewhere. If he would have use the TA DP intake the Edelbrock probably would have worked better. But since he went with the SP3 Single plane that makes it harder to get off idle quick. No heat for the intake is a big thing to get the gas to atomize and spread out to all cylinders. Two little openings in the carb and the back two are waiting for vacuum to open the rest. and there lies that big opening below the carb just waiting for something to open/ happen. If you had a 410 gear the engine would be at 4 grand instantly and the back two would be open. You aint goin nowhere with the big hole under the carb and 256 gear or 310 for all that matters with the engine at 2 grand and those two front barrels trying to feed the big hole again waiting for those secondaries to start opening at 3 grand. Crap your over by then take it home put it on the trailer LOL. Until the car gets a gear in it the double pumper may not do it either out of the hole but at least it will be taking care of the big hole under it. You can tune that response at least. 342 seems to be a good street gear if you need to drive on highway To me I think anything under 5500 rpm does not need the Sp3. Spin to 6200 yes it will help I could see my hp fall of quickly after 6200 on the dyno which the DP intake was holding it back.
3.42 gears out back, one of Jim's 9.5" converters, and that DP carburetor, and it will be a different car. How many pages ago was that?
I feel like we are beating a dead horse. Either you set the combo up correctly, or be disappointed. You're trying to get away with murder with a plastic knife and a broken down getaway car. Some parts of the plan may work, but its failing. Either everything gets upgraded, or the results aren't going to come. 3.42s, a JW converter, and the Holley should work wonders for you. However, upgrading one part at a time is like replacing the knife with a gun. Yes, that's great, but the getaway car is still broke down There's a reason good combinations SHOCK people
I appreciate everyone chiming in. Engine first then I'll do the rest. I had a 50 year old car that had been sitting in a shed since 1988. Grease and mouse poop was a mile thick all over the engine. Its low miles but still had a failing water pump, leaky radiator, drove it home 3 hours with bouncy shocks and brakes that barely worked. I put all new suspension and sway bars on it immediately. 8 months went by and I pulled the motor. I'm all in on this car. I will keep upgrading it as time goes on. It will be my main vehicle for doing estimates for the gutter business that I operate. It MIGHT see the track a few times for a fun family night out. multiple people in my family have hot rods. It needs to have good highway gearing. I'm planning to do disc brakes, Exhaust, a/f gauge, then a stall converter. Occasionally my edelbrock would produce a similar burnout as my stock setup. I'm okay with that level of performance for a while if its at least consistent. When I had the Edelbrock jetted 3 stages rich it had a mid-range power band that was extremely impressive to me. Couldn't get the bog tuned out though. never made a video of it 3 stages rich but if I was going 15-20 mph in second gear...maybe 1st and hammered it it would break the tires loose.
I knew atomization was an issue with single plane airgaps and I knew the specs on the cam were 2k-5k. the annular boosters help with atomization and low end torque. That's why I went annular with the edelbrock and with the quickfuel. I was super stoked to find an annular double pumper under a grand. Much consideration went into my parts. Big tube headers matched the cam well, cam was "supposed" to be good with stock converter, intake was "supposed" to be a hybrid that performs well down low. This is all straight from TA. 650 cfm was "supposed" to be "more" than enough carb. I think in the end this is gonna be a lopey, screaming 9 to 1+ cammed up double pumping 350 that kicks @$$
Seems you are determined enough and will eventually get the results you are after. Wishing you warm weather and no snow.
I read 100s of reviews written by individuals that loved the annular edelbrock. Buick is just a whole different animal. Plus too small of carb. I have a very mild 406 in my Chevy pickup. I will let you know how it runs with the avs2 vs the performer. Kinda wonder if the 800cfm avs2 would have worked good. They are easy carbs to work on and run forever. Sucks this is where I'm at. This quickfuel is so tunable and I know nothing about it. Been reading up on holleys trying to learn but they ain't quite the same
A pump cam kit is good to buy. Actually I bought a big kit from Summit that has shooters with pump diaphragms, gaskets for shooters some pump cams with jets too. Have to go out to look at it been a while I keep notes in it. it all takes time and of course mistakes will be made along the way once you learn from us dummies yours will be easy
After a couple of days or so there is a bunch more pages and other posts in other areas with a few beers mixed in or wine along the way with a few shots you tend to forget what happened or what is going on.
Does your 406 have a single plane intake? It's a very mild 406? Buick engines are not that different. It's a shame you didn't find us sooner. Might have saved you some money. Very curious to see how it runs with the DP carburetor.
Idles richer than my edelbrock. Exhaust burns my eyes a little with garage door open. Edelbrock never did that. Might drive it today but still have a couple hundred yards of snow pack between my garage and the hard surface road. Its supposed to be 30 and sunny. The snow is becoming soft which is easier to get traction on. I live on a hill so I may not make it back up the driveway. I'm itching to drive it though.
