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Your recipe

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rsrguy3 View Drop Down
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    Posted: May/14/2022 at 2:26pm
So I'm away from home at a relatives home waiting to loose a member of the tribe, too much time on my hands for reflection, and I can only eat so much so I thought I'd throw this question out as a means to keep my mind occupied with something else...
 My motor is built, it's a 401 with cast/hypereutectic?.... pistons and a mild cam, I have the stock doglegs and cast exhaust manifolds and the air gap... And a efi from fitech. 

Just wondering what your various recipes for a 450 hp street-able mostly tame motor would be. I know I have no where near that, I'm just thinking about what it would take. 

Aluminum heads, roller cam/rocker set up, headers? How would you build a solid 401 setup? 


javguy
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BassBoat Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2022 at 2:45pm
My plan for building from scratch is to pick a power band I want, spec the cam to give me that power band, and then build with compression that compliments the cam.  Example, I had a 10.75 to one 390 with a 246 duration cam that worked fine on pump gas.  Maybe a couple of gallons of race gas for track days where I wanted to crank in a little timing for max power.  Using the KB-Silvolite effective compression calculator I had about 8.75 effective compression.  So for a pump premium, splash of race gas I try to get close to that 8.75 number.  That 390 had the pistons down in the hole, so not a good quench design.  My more stock 390 has less compression and milder cam, and with 8.6 to one effective compression will run on 93 octane.  My next build is a 417 that will have good quench, same 8.7 ish effective compression and I expect it will not need race gas, but don't care if it does.  My target power band was 3500-6500, like I had before and met my goals.  You really can't do much about your compression, but you can raise or lower your power band with a different cam.  



Edited by BassBoat - May/14/2022 at 2:53pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BassBoat Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2022 at 2:51pm
My more stock 390 had an issue that required pulling the motor apart for a "do over".  It worked well so I didn't change cam or compression.  I did send the heads to a friend who ported them.  I then had my regular shop put guides in, and while they were at it bigger valves with smaller stems.  A slippery slope, lol, and an expensive one.  I had always assumed that ported heads made more power because you could rev higher and take advantage of bigger cam.  I was pleasantly surprised that I made a lot more power with the same cam and same shift points.  So a significant boost could be achieved with Edelbrock heads in your case.  If you like the power band you have, If you calculate that you can tolerate the increased compression from the Edelbrock heads, then you can get power without tearing into the engine.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote rsrguy3 Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2022 at 9:09pm
I've been driving mom mobiles for the past 20+ years, the last time I remember driving this thing in anger it seemed to pull very hard once it hooked up, so I haven't the foggiest on how to pick a range that I'd like for it to make power in...
I'm not bombing the interstate in the wee wee hours of the morning so I'm guessing I'd want the most power and torque up to 3500, but really that's an ignorant guess. 
javguy
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 7:24am
A recipe:
Assuming you have an automatic and using other parts you described.
Wiseco -27cc pistons, Don't know what you have so these may not be required.
Lunanti 702 camshaft
Edelbrock heads
2-1/2" dual exhaust, headers not required.
725 CFM carburetor, likely have to go 750.
That's 450 HP @ 5350 RPM and premium at the pump. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rgsauger Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 8:23am
Sorry about your relative.  Those times suck. 
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rsrguy3 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rsrguy3 Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 9:50am
Ya it’s rough we’re practically the same age. Thanks
javguy
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rsrguy3 Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 9:53am
Originally posted by Trader Trader wrote:

A recipe:
Assuming you have an automatic and using other parts you described.
Wiseco -27cc pistons, Don't know what you have so these may not be required.
Lunanti 702 camshaft
Edelbrock heads
2-1/2" dual exhaust, headers not required.
725 CFM carburetor, likely have to go 750.
That's 450 HP @ 5350 RPM and premium at the pump. 

This looks reasonable I’ve started saving for the heads shouldn’t be hard to do the cam too…
javguy
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rsrguy3 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rsrguy3 Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 10:10am
Is a roller setup worth it on a non race motor?
javguy
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PROSTOCKTOM Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2022 at 10:45am
Originally posted by rsrguy3 rsrguy3 wrote:

Is a roller setup worth it on a non race motor?

Absolutely if you can afford it. I advocate a roller cam before spending money on aluminum heads all the time.

Tom
Molnar Technologies Full Service Dealer - Crankshafts & Connecting Rods

1969 AMC Rambler Rouge Race Car
1974 AMC Hornet Hatchback, Wally Booth Outlaw Nostalgic Pro Stock Race Car Project
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