engine ID
- Thread starter tumtum
- Start date
- Status
For a stock 400? No. There are much better choices. I am a bit biased against Holleys since I find them a bit crude. They are great at WOT, but marginal everywhere else. Given the choice of universal carbs, I prefer the Edelbrock. However, I feel the Quadrajet (or Carter/Edelbrock AVS) is best suited to anything but all out racing. It's also cheap to buy if you have a u pull it type yard. You just have to know which core to choose and how to check it out. Get one off an engine of similar size with tight throttle shafts and you should be fine. The idle feed restriction is set up by the factory for the size of the engine, and going too far from the stock displacement of the engine the carb comes off of will make it too rich or lean. This is one of the principle problems many people have running a 3310 on a 350. The 3310 was designed and calibrated for the Chevy 396. This is why they tend to be too rich on a 350 unless you put a small piece of wire in the idle feed restriction to reduce flow.
I agree with 85 Cutlass except that I personally do like Holleys, I've had good luck with them myself and there's alot of neat stuff you can do to tune them. I've got a good running Quadrajet on my car right now. Trade ya. lol I say if you got it free, what do you got to loose (except a little gas mileage, lol). Try it.
well i also have a holley 6210-3 which someone at holley said this is a 650 cfm with mechanical secondaries. would this carb work better? like i said i have a edelbrock (#1406) 600 cfm on it right now and i would like more power. should i leave this carb on and focus on other things? if changing the carb is my best bet, what carb does everyone recommend. this is a daily driver. but i would like to take it to the local track every week as well. im open to any advise. you guys have been a big help.
Mortec.com is a good place to reference casting numbers and Holley carb info.....it may help you find more info....Lorne
Your carb is not restricting the power of the engine. If it is otherwise stock, you need to work on other areas to see a performance improvement. What intake is on it? What is the compression ratio? Cranking compression? Cam? Heads? Exhaust? Headers or Manifolds? The 600 Edelbrock is a good carb if the engine is otherwise stock. Tune what you have first, set up the distributor properly, tune the carb, etc. If the engine does not like to run above 5,000 RPMs (stock internals 400's should NOT run above 5500 at all costs!) it's pointless to use a bigger carb unless it's a 454 or bigger.
ok like i said i havent had this engine long at all. i just wanted to find out if this carb would still work good if i enhanced my engine at all but i guess u guys need to know what i have in able to tell me what to get. well its dark now but ill go out there and take list of everything that i have. this might be a dumb question but how do i figure out my max rpm's?
Well, if it's stock you can figure it out by "common knowledge". If it is a Chevy 400 with a stock crank and rods, it will be on the verge of throwing parts out the oil pan if you go beyond 5500. It's a torque engine, not a horsepower engine. There are other ways to build a 400, but they require more money and custom pistons. Same goes for a Chevy 383 built with the stock 5.565in 400 rods. The problem is that the rod/stroke ratio does not lend itself to high RPM's because of excessive loading of the cylinder walls and pistons due to connecting rod angularity issues. So, when you pick out a cam, intake manifold, etc. you should choose parts that enhance the low end and mid range torque this engine is best used for, then gear the car accordingly. Remember that horsepower is a mathematical function of torque and RPM, and is not an actual measured figure. Similarly, gearing is a mathematical function that multiplies torque. If you have more torque at a lower engine speed, you can run taller gears than a horsepower engine that needs to rev to make it's power. Think of horsepower as a small body hammer, and torque as a sledgehammer. In order to do an equal amount of work with the body hammer as you would with the 5 lb sledge, you need to hit the object in question many more times. This is why horsepower is RPM dependent. It makes up for the lack of torque by increasing the number of events in the same period of time ("Minutes"). A good example of a HP engine is the Honda B16B1 VTEC 1.6 liter 4 cylinder. It only makes a peak torque of around 117 ft/lbs, but it makes a peak HP of 170. It also revs to around 9,000 rpm. Now the lamest of smog era (1976-80) 400's also makes around 170hp, but the 400 also would make over 300 ft/lbs of torque. It just doesn't have the RPM's to make the horsepower function look good. However, it will be more usable than the Honda in a heavy car like a G body. (In a light car like a CRX or (my biggest wet dream)an original Mini the 400 would be a weight liability, but that's another discussion on the physics of vehicle dynamics) Staying with the Honda, to really be able to use that engine to make a G body as quick as it would be with the 400 you would need some amazing rear gears and a transmission with lots of gears too because you would need to scream it to the limiter all the time.
No, I am telling you NOT to try for horsepower. Try for torque instead. If it's as street car that's what is important. I was trying to relate theory to you, not tell you to go in a direction that does not work with the parts you have. For a cam, it will depend on your heads and compression ratio. If it has low compression, I would go for something like a Comp XE 268. The 400 naturally builds more cylinder pressure than a 350 with a similar compression ratio, so it can tolerate that cam if it has at least 9:1.
- Status
Similar threads
