| Re: 383/DMF considerations |
Subject: Re: 383/DMF considerations by rklessdriver on 2009/9/27 18:48:27 Quote: To be honest, I bought a cam (and cut my heads) based on a 350 motor. It's a custom Bullet 214/214 with .544"/.544" Ok you have the Bullet HR269/340 lobe. That is a symetrical lobe desgin with a very smooth ramp desgin. IMO it is a very good choice for a long runner TPI intake but not much else in a 380 inch engine. What did you have the intake centerline and lobe seperation cut on? I need that info as well. Quote: Are there any forged pistons that will minimize/prevent noise during warm-up. One shop said hyper's were better because they weren't noisy. They added, forged isn't necessary for a street car. Ideally you want something forged from 4032 alloy - but 2618 alloy is also acceptable. Either material will run with .004 of piston to wall clearance in a 4" bore and be safe in your application. I have .005 in my engine with ultra light Manley pistons (2618 alloy) and it dosen't have any piston slap at start up. Some people get by or have gotten by with Hyper pistons. I'm in the latter. I've used the KB hypers before... even in some lower powered bracket engines without problems. I think they are a trade off. You have to open up the ring end gap to run them and I don't like to do that any more than nessescary. Ring end gap in a hyper piston motor is CRITICAL. If you run it too tight it will butt and break the top off a piston. Hyper pistons are not strong at all. They are also very brittle and if you get any detonation at all they will come apart. IMO they are stock replacement parts that can be used in hi performance engines if the owner/builder understands their VAST limitations. I stand by my recommendation of KB or Probe forged pistons and add in SRP and Mahle depending on how much you are willing to spend. Hypers are a possibility but we are talking that KB hypers cost $275.00 and KB FHR Forged cost 285.00 for the same application (4.030/3.75/5.7/18cc dish)... The better Forged pistons cost between $350 to $550+. It is not that much money IMO but there is that much difference in strength. Quote: I haven't heard any recommendation from anyone on rods aside from using SIR or I-beam rods with ARP bolts. NOT BOLTS. I stated CAP SCREWS. Scat offers a rod with thru bolts (like stock) and one with 3/8" capscrews. Buy the latter. Eagle switched their SIR rods to 3/8" capscrews about 3yrs ago. For all intense purposes the cap screw rods are equall and I would by the lowest price one. The Scat 9000 is a good crank for what your doing. But I'm with Joe, be sure of what your buying. I know for a fact Eagle offers a 3.75 cast crank that is external (rear) and internal (front) just like the Scat and factory cranks. Like I said about the DMFW balance deal.... Keeping it in the stock configuration is your choice and does have it's advantages. If I were in your position I would probally try to do the same. Will |
