401's love extra lift close to .480 lift with no mods. summit 8600 is a great basic cam for stock pistons with a 401.
The edelbrock cam is WAY too small for a 401 especially witht he shift points you are talking about
I opened up and polished my combustion chambers just a hair on my next motor, also opened up exhaust and port matched intakes. it has speed pro pistons though i wish i had gone with the KB's my compression ratio is 9.6:1 i have a 5.12/.512 lift cam at 226 dur @ .050 274 adv on a 112 lobe seperation running a air gap intake a holley 670 and hei ignition, with a 5 spd.
Current motor is a 401 bored .030 over with speed pro forged pistons and a 9.6:1 CR i have the crane HMV272 .484/.512 218/228 dur @.050 272 adv dur on a 112 lobe seperation with a performer intake shorty headers and a 3" exhaust. i run HEI and currently a holley 670 though i also had a edelbrock 750 on here before. the holley 670 picked up a little snap to it and has served me quite well, the 750 had just a little bit of a dead spot off the line (very minute) but it also needed the offroad kit and i already had the 670 sitting in my garage so hard to argue.
That said the jeep has 33's and a nv4500 and at one time 3.54's though now it has 4.10's since i swapped to a j10 rear axle. it tows a trailer regularly around 6000 lbs. with the 3.54's in direct which is the gear i spend most time in when towing i cruise right at 2500-3000 rpm when i down shift into third to pull a steep hill it gets right up there in rpms to 4000+. This combo has proved to be a great balance of power, towing ability and hp.
Sweet spot for best mileage would be keeping with lower rpms
i average 9 mpg when towing and get 12-14 when empty. i cruise the road in od empty at around 2000-2400 rpm. though it can cruise at 1800 in od with no problems either. it has power off idle all the way up to 5000-5500 rpm which i dont think ive ever seen over 4500 rpm yet but it pulls hard off the line all the way up.
honestly if your going to run 3.54's id say take a look at that comp EX268 grind, if you like a little more rpm with shift points in the 4k -4500 id look at the hmv272. I have no detonation problems with my higher compression pistons and once i recurved the distributor that helped a little more. i did have to jet up the 670 though it was under jetted.
Engle makes some great cams for amc motors, they know how to take advantage of the performance these motors are capible of.
you are in chino ca right? you will have smog to contend with so that may be an issue there are ways around that but thats for pm. if you are ever in norcal bay area or sacramento get a hold of me you are more than welcome to take it for a drive and see if the power is what you are looking for.
for stock pistons and an rv grind look at the engle s or howards had a 479/479 222/222 dur @.050 114 lobe sep cam that works really well with stock compression in a 401. nothing extravigent but rpm wise 5k is about all shes got
Last edited by dusty : 10-17-2007 at 10:44 AM.
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