I'm going to be building a decent street, probably blown, 1951, 331 for my Plymouth coupe and i was wondering what every one else is running for compression, cam grind, and valve size. Also in anyone has any other tips on 331's i'm also interested. This aint my first hemi only my first chrysler.
Hey I thought this was tech week? Come on not everyone here has sbc's Hemi guys help me out, I'm especially inerested in what has to be done for a street blower.
I'm building a 392 as we speak. Bored, stroked, 440 rods, cammed, blown, ported, polished, etc. I don't really have any experience with 331's, but I'll help if I can. If you haven't done so already, get a copy of Ron Ceridono's "The Complere Chrysler Hemi" It's an invaluable resource. -Bugman Jeff
51 F-3- I have a 1955 331 waiting for my next project. Go to www.powerplayhemi.com for some really good info and parts and free online hemi swap meet. Also get PAW's (performance automotive warehouse) catalog for early chrysler hemi. They even have complete engines available. You should also check out 54 and up blocks. They don't have the extended bellhousing cast as part of the block. On powerplay's site you can read the difference and get some real good ideas. overspray
Here's some basic info for street blowers.. http://dyersblowers.com/engine_recommendations.html http://www.blowerdriveservice.com/recommend.htm Dan
51 F-3, I have been told that small block chevy pistons will work in these engines. (Not real sure about pin height but 283-305 may hav a small enough bore size to work.) I do know for sure that big block Pontiac (400-455) rods will work as they are the exact same length.(6.625) (Pin size is .984 for the hemi and .980 for the Pontiac.) The big end is the same diameter on both. Heres a couple sites to check out. pontiac specs 331 hemi specs hot hemi heads Good luck with your project. Hope this info helps. Eric ============================================================ Hemi Powered 49 Studebaker P/U (someday!!!)
basic blower tech applies to about anything that you are going to build. Hemi or otherwise. So if your serious about building a blower car you need to be planning for it from the GIT. #1 This actually applies to anyone who is thinking about going fast blower or not. Balance and Blueprint. You're putting a lot of pressure on your lower end (and everything else); give the mill a break.There's a good book SA Designs Engine Blueprinting. Should be on the shelf right above your Chiltons in the shop. Unless you were lucky enough to learn from one of the masters of course. #2 Lower compression and Forged pistons. At the very least Hypereutectic pistons. Drop your static compression down to about 8.0:1. You're going to be force feeding the mill, give it some room in the cylinders for what you're ramming down its throat, and some pistons that can take the stress. #3 Wide valve faces. Your valve grind is more important than port work or valve size on a blower. And portwork is pretty important. Give your valve a good place to seal, and hold the pressure where it belongs. Strong springs, you want that ****** to slam shut and stay that way. #4 Cam Shaft. Buy a blower specific grind. Most of the Companies build 'em. Wide lobe separation, little or no overlap... Run your cam straight up. Buy a degree wheel and make sure you know what your valve timeing is prior to lighting it off. #5 Boost, the ol' man always said if you're running less than 12 pounds of boost you're whistlin' in the wind. Most guys run 8 pounds on the street. I might not go 12 but... Now I missed most of what you need to know about huffing one. There's a good book that I have somewhere and I can't remember the name. But when I find it I'll PM it to you. Play hard or stay home
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