Ballpark HP for my 401 help please

[Magical_Merlin]

I have a 77 401 bored .060 over
9.5:1 Pistons
Comp 270H cam
Howell EFI
502-1 casting heads, mildly ported/polished.
Also has been fully balanced, including the clutch pak.

Anyone have a ballpark HP number for this configuration?

If you need more details, let me know.

[Lenni AMC]

I would say easy 450 hp maybe 500+ ft of tourqe

[fifesjeep]

Toss on some aluminum heads... I'm wondering if the EFI will choke it at the higher rpms...

[Old Rugged Crosser]

Lenni-- Magical_Merlin would have to do some of his magical tricks to it to really achieve those numbers!

The most potent 401 from the factory was put out in 1971 : 401-4B(Early) 335 h.p. @5000 torque: 435 @3400 10.2:1 comp. 4.165 x 3.68 bore & stroke.

It takes a lot of work to get beyond that.

[Lenni AMC]

I disagree and here is why. There is not so much trouble going for 1 hp per cui with a relatively small budget just read the many articles from Hot Rod magazine like this one here http://www.carcraft.com/techarticles...ild/index.html
Here you can see a fresh build 360 engine but stroked to 370, I realize they are doing somethings that maybe our 401 buddy isin´t doing like longer rods and alu heads but he has more cui and that gives a lot.

I´m not a big fan of these edelbrock alu heads because they don´t flow much more than stock AMC heads with a mild porting job also you can see they are not running a big cam here but getting 437 hp that´s impressive. the cam they are using is not so different from the calm that our 401 friend is using..

And finally the compression ratio is higher on the magazine engine that this one but here´s something I have realized a lot of people think the compression ratio is making a BIG change in horsepower and tourqe output but this is what is really happening from the stock 8,4:1 to 9,5:1 compression there is a lot of difference both in power output and MPG but from 9,5:1 to 10:1 there isin´t really maybe something in MPG but a few hp

For example I saw and article couple of years ago and they where having this trouble with a drag engine that had 15:1 compression ratio and turned out 860 hp but the guy who bought it wanted to put it in his street car so he could drive it so they desided to lower the compression ratio from 15:1 to 11:1 and dynoed the engine after the change and it turned out 820 something hp so here you can see the higher you go with the compression it makes less and less affect.

Maybe my numbers are of 20 hp or even 30 but The 401 motor we are talking here is a EASY 420++ hp in my opinion but maybe you know something I don´t ?

Best Regards Leonard from Iceland = )

[fifesjeep]

Build it, dyno it and post a picture and or video of the results... actual/visual facts will put the guessing to the waste side... BUILD IT, and it will show us. ;)
I'm going with 434hp 468ft-lbs of torque

[Magical_Merlin]

I dont have any way to dyno it. I am just wondering what the ballpark figure could be.

I just read this article also.
http://www.carcraft.com/techarticles...nes/index.html

[fuzz401]

300 to 350 HP to the ground
380 to 425 FT.- LB. torque

[Old Rugged Crosser]

That my friend, is much more realistic.

By the way Fuzz how are the eyes?

[Magical_Merlin]

Wow. Thanks.