Originally Posted by bdd1469
In all my years messing with small blocks I have learned many things. One of the first things I learned is the long stroke in a 400 kills its rev potential.
You can talk about bigger heads and more ci all day but a 377 will rev so much quicker and higher with good parts it is no comparison imo.
Have you ever built a 400 that revved like a 350? No, it wont spin because of the long stroke...... dont give a fukc what head is on it. It's the rotating assembly that slows it not the amount of air air the heads flow.
We have built 400s and 377s with the best money can buy and the 377 will stomp a 406 every time in the upper rpms. A 377 with cola crank and oliver rods will spin to the moon,happily. A 400 with same parts wont go past 6500-7000 from what we have built, and takes all day to get there.
You need more then 23 ci to make up for 2000 rpms.
Gm made the 400 for trucks and heavy cars, if it had hotrod potential it would have been in camaros, novas, and chevelles.
Its a great torquey motor for a truck but the upper rpm power just isnt there imo.
Unless you actually build a 377 from your 406 you will continue to argue and throw out theries. Fuck theries, they dont win races.
And as far as a street machine goes it depends on the person. Im totally happy with a huge cam, low vacume and less torque down low. I like my street car to sound like a race car and run like one.
The 406 in camaro is quiet, makes huge torque and is a blast to drive. Anyone could drive it. The dz302 I had in it before made no torque,was lumpy and hard to drive.
I enjoyed each motor for what it was. I would bet my 302 put out the same hp with 100 lbs less torque then my 406. In a dragrace I think the 302 was just as fast because I cant hook up with the torque the 406 makes.
The 406 and 377 both great motors and each has their place. If I was building a car I would build a 377 because I am a rpm junkie. If I was building a truck I would build a 420 because torque at lower rpms work best.
Sorry to continue jacking your thread jake. I have always learned more by building shit and seeing what works then by listening to reason and theories. Just my. 02
The argument is invalid. If someone had a Cola crank and Oliver rods in a properly built 406, they wouldn't have built the 377 to begin with (unless they didn't have enough head). A friend runs the same parts as you describe in the bottom end of his 406 and he starts off at 6500 on the brake and shifts at 8000. That's before the spray.
How important is spin up again? The engine only has to spin up another couple thousand rpm after launch? I'm sure it can get that done in a few seconds, maybe even a couple or more times during the quarter mile...
And you say, your built 406 with these expensive parts couldn't get within 2000 rpm of your 8500 rpm, 377? Really? My hyper-eutectic piston, hydraulic-cam 406 has no trouble hitting 6500 rpm and yours can barely hit 6500 rpm with the best parts money can buy? I smell something and it's not race fuel.
And, I've yet to see an engine that wouldn't rpm real quick with a healthy shot of N20.
Using your rationale of 377 is better than 406, we'd still be building "301"s (you know, that engine gear heads built before GM released the 302) because that "long" 3.48 stroke in the 350s revved up too slow. Don't forget, the big block guys better hurry up and swap their 454s back to 427s.
Displacement rules, if you have the proper parts to support it.