Jay-ten
I am new to the forum and have a 401 build question.
I am preparing to rebuild a 401 I recently picked up. I am targeting low end torque first and horses second for off-road fun.
I was wondering if anyone has a good estimate of what kind of power and torque the stock 401 forged crank and connecting rods are capable of?
I would like to reuse these, but need to know their limits before I decide.
Also, does anyone have any feel for torque/horsepower vs. $.
I keep remembering the old race adage "Horsepower costs money - how fast do you want to go?"
So if someone has an idea of torque/HP vs build cost I'd really appreciate that info.
I have only rebuilt three engines and only to get them back on the road. I have never built something with specific use and design targets - so I may ask some stupid/ignorant/newbie questions without warning.
Thanks
ironman_gq
not sure on how much they can handle but 400hp should be no problem for em if they are in good condition. As for your build a good cam and intake witht the right carb and maybe a little prt matching and a slight bump in compression should get you into the 300's with no problem possibly even deep into the 300's. If you do a full rebuild with a 30 over bore and get the block decked to keep quench where it should be and have the heads shaved a little you should be very happy with the motor
fuzz401
balance and polish the rods they will take 7000 rpm all day
jeepsr4ever
After nitriding the stock crank can handle over 800hp. If you plan on that number or above then you will be doing the mag checking for microcracks and a quick prayer before assembly. :?:
tufcj
Jay-ten
Has anyone used Desktop Dyno or Dyno 2000 that they could recommend a package?
tufcj
For torque, keep the compression in the 9:1 range, cam around .480-.500 lift and 110-112 lobe separation. Shot peen the rods and have the rotating assembly balanced, and it will live a long life at normal RPMs.
AMC engines really like to breathe, so spend any extra money on a good 3 angle valve job and at least pocket porting of the heads.
Look in the e-store here and get the modified cam bearings to get a little more oil to the mains. Make sure the oil pump housing is still within spec, and replace if the clearance is too high.
A 400 HP, 500 ft/lb 401 isn't hard to achieve.
Bob
tufcj
