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have a 406 going into a 1979 corvette with the following 3.73 gears, the 406 has the following camel hump heads, aggressive comp cam, edelbrock intake, holley 650 db pump, crane cam rockers, hedman headers, high performance fuel pump. the estimated horse power is 450 and 550 ft/lbs for the torque. The guy putting in the engine is constantly telling me to go with at least a 3500 stall. This will be a daily driver/cruiser and from what i have read, people choose 2400-2800 in their street driven vehicles, oh and also the guy putting in my motor is also redoing my trans and says all i need is a TCI shifter improver kit, with the kevlar bands to with stand the torque from the motor. what do you guys think? 3500-3800 TCI torque converter too much?
have a 406 going into a 1979 corvette with the following 3.73 gears, the 406 has the following camel hump heads, aggressive comp cam, edelbrock intake, holley 650 db pump, crane cam rockers, hedman headers, high performance fuel pump. the estimated horse power is 450 and 550 ft/lbs for the torque. The guy putting in the engine is constantly telling me to go with at least a 3500 stall. This will be a daily driver/cruiser and from what i have read, people choose 2400-2800 in their street driven vehicles, oh and also the guy putting in my motor is also redoing my trans and says all i need is a TCI shifter improver kit, with the kevlar bands to with stand the torque from the motor. what do you guys think? 3500-3800 TCI torque converter too much?
Find a different "guy" because this one is clueless. Hope for your sake he didn't do the build.
You certainly need a higher than stock stall speed, but how high depends on if you intend to do any serious drag racing with the car. The more racing use, the more stall speed will be justified. I have a mild 383, 3.73 gear and a 3,000 stall converter. I bracket race the car about 10 times per year and I feel that's a pretty good justification for that converter. A higher stall and less racing wouldn't make sense in my opinion.
Modern converters are more efficient than the older ones. I run a 3500 rpm stall with lock up and it works very well on the street. It does not stall way up unless you are at or near full power. It drives well below 3500 not locked up, does not feel like it's slipping and is not making excess heat. It is a Art Carr converter.
Some old high stall converters I have run into in the past did not work well on the street. They stalled way up just in normal driving, felt like they were always slipping and made a lot of heat..
As far as the motor build, I have to agree with 63 Mako. The double hump heads, be it 461, 461X, 462 etc.., are way to small for a 406 with a large cam. The heads will stall out at 4,000 rpm to 4,500. If your cam is meant to make power above that point, it is a big mismatch. Not to say it won't run, but it will be far from ideal. New bigger port and valve heads are needed to make an engine that will rev high enough to make good horsepower. A smaller cam would work to make a good bottom power build with the existing heads. The Headman headers are 1 5/8" primaries I believe. These are also too small for a stout 406. They would work for good bottom end torque with the right cam. The 650 DP is small for a high horsepower 406, but again, would do well with a small cam. The one other thing you need to be careful with is compression ratio. The old heads do not have efficient chambers and are more prone to detonation than modern hi performance heads. Again, for a matching build, if you run 9 to 9.5 to 1 compression with a mild cam, the 1 5/8" headers, the 650 DP carb, and the old double hump heads, it should run fine and have a strong bottom end pull with decent mid range, and you won't need a very high stall speed.
I would find out from the builder what the cam specs are, the compression ratio and squish clearance, and what was done to the heads. You can then post here and get some recommendations!
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75 Roadster, 406", Ported Brodix -10 Heads, 2.100"/1.600" valves, 11.8 to 1, Ross Ultralight Pistons, Custom Solid Roller, 650/609 lift 248/252 dur 110 LSA, Comp 1.6 in./1.5 ex. Extreme Gold Rockers, 7/16 Studs, Stud Girdle, Ported Dart Single Plane, Modded 850 Holley, Jet Hot Coated Hooker Super Comp Headers, 3" Mandrel Bent X Pipe Exhaust with 2 Chamber Mufflers, Art Carr 700R4, 3500 stall lock-up, 4.11 posi, Nitrous. 265/40/18 F1, 285/40/18 F1 Goodyears on chrome 5 spoke Vision Legacy Wheels.
I have a 2100 on my street driven ZZ4. I love the performance. I have never driven a car with anything higher so I can't tell you what something else is like. However, love driving my car now.
Vodoo! so if you will drive her on the street regular dont over cam and match your converter to the cam as stated before. Otherwise you will not enjoy driving your vett as you should on the street. My 383 runs low 12s all day and is a pleasure to drive daily. Im running the stock converter but could use a little looser one for idle quality at the lights. good luck with yours. PS Overcaming will hinder all your vac, assesories from working unless you add a vac can.
With that cam, you'll probably want nothing less than 3k stall. The 3.73 gears and the car's light weight are going to affect the stall speed downward if this is a generic off the shelf converter. That cam isn't going to make very much torque down low and you're going to be very unhappy with the car's overall performance if you don't have enough stall. I'd follow your builder's advice on this one.
Make sure you figure a large auxiliary trans cooler into the equation.
casting # is 378461. 65cc thats the casting number for the heads any good?
The 461 heads were the head many years ago, but small blocks were generally smaller inches and there was not all the aftermarket heads available. The ports are only 165cc and the chamber is not very efficient. I would go with a AFR, Dart, Brodix, etc.. with 2.080" to 2.100" intake valves and at least 200cc ports, 220cc + would be better. Then you need an intake to match the rpm range of your heads and cam. You did not mention what intake you are using. The recommended converter for your cam is 3000 + on the spec sheet.
Are the pistons flat top, domed dished, reverse domed? What intake?
So far it looks like a smaller cam is in order to save this build, as long as your compression isn't above 9.5 to 1.
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75 Roadster, 406", Ported Brodix -10 Heads, 2.100"/1.600" valves, 11.8 to 1, Ross Ultralight Pistons, Custom Solid Roller, 650/609 lift 248/252 dur 110 LSA, Comp 1.6 in./1.5 ex. Extreme Gold Rockers, 7/16 Studs, Stud Girdle, Ported Dart Single Plane, Modded 850 Holley, Jet Hot Coated Hooker Super Comp Headers, 3" Mandrel Bent X Pipe Exhaust with 2 Chamber Mufflers, Art Carr 700R4, 3500 stall lock-up, 4.11 posi, Nitrous. 265/40/18 F1, 285/40/18 F1 Goodyears on chrome 5 spoke Vision Legacy Wheels.
The 461 heads were the head many years ago, but small blocks were generally smaller inches and there was not all the aftermarket heads available. The ports are only 165cc and the chamber is not very efficient. I would go with a AFR, Dart, Brodix, etc.. with 2.080" to 2.100" intake valves and at least 200cc ports, 220cc + would be better. Then you need an intake to match the rpm range of your heads and cam. You did not mention what intake you are using. The recommended converter for your cam is 3000 + on the spec sheet.
Are the pistons flat top, domed dished, reverse domed? What intake?
So far it looks like a smaller cam is in order to save this build, as long as your compression isn't above 9.5 to 1.
This would be a much better build with some nice aluminum heads, drop compression to about 10 to 1, and a cam in the 230 duration @ .050 range. 500 hp at a lower, more useable rpm with much better street manners and about a 2200 stall convertor. JMHO
I dont want to have to redo the rear end, i read that the rear end can handle the 450hp which i want to keep around there i am just worried about the street ability, i am more then willing to change the heads but am worried about the tranny and rear end. please any corrections if i am wrong and i appreciate the help guys!
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Help picking a torque converter
This would be a much better build with some nice aluminum heads, drop compression to about 10 to 1, and a cam in the 230 duration @ .050 range. 500 hp at a lower, more useable rpm with much better street manners and about a 2200 stall convertor. JMHO
