maybe not this one but a full top end kit...it's a domino thing. Oh, don't forget the carb...LOL https://www.summitracing.com/parts/edl-2045
I would also build the motor before getting a new converter. that way it will match the extra/less power you will have.
I would more likely buy a set of reconditioned GT40 heads which already include screw in studs before sinking even one single penny into those "rebuilder specials". What casting number on the existing heads? Good cam on those GT40 heads will put you up an easy 40-50 horsepower and make much more average power to keep a stupid teenage grin on your face every time you drive it.
Before I'd use 300Lb springs with press in studs, I'd get a set of E7 with bolt down rockers...In reality I wouldn't use those either, both my 306 & 331 use aluminum heads with 7/16" screw in studs...
Yes your best bet is to go with aluminum heads instead of dumping money into those boat anchors.then you have to decide wether to just do the upper or save up a couple bucks and rebuild the whole motor while you're there and up the compression alittle.
I think he should do a 347 stroker with aluminum heads, 300* duration cam, single plane intake, 750 double pumper, 1 3/4" headers w/3" exhaust, nitrous...
The engine has less then 2000 miles on it so I wanted to put a cam and roller rockers for now while I build another roller motor that I have to what I really want in it
how about swapping out the springs and going with this cam setup? https://m.summitracing.com/parts/sum-k30062
Or...he could stick to his original idea and put a mild performance cam in his stock 302. (yes, I totally get your comment) People are advising him on things he never asked about.
Again, too much cam for a low compression motor with an auto trans, stock converter, and tall gears. Why not follow the first two suggestions in this thread?
Just throwing out some possibilities to see what everyone thinks but it looks like I will have to pick one of the first two suggestions or close to
A stock engine loves the comp cams high energy 268H cam. It will give your stock 302 just enough to work with stock springs and converter... Anything more will require upgrades... That is my 2 cents...
As far as replacing heads goes.. I wasn't advising anything. Just stating the simple fact that by the time you start the snowball rolling down this slope.. you'll eventually look back and see what we have said about these particular lo-po parts being nearly a complete waste of time and resources when more performance is desired. But.. the fact that you are just trying to "1-up" what you currently have until you get more serious about another motor pretty much says it all. So, I will say it again. Stay shorter on the duration to keep cylinder pressure up for such a low CID/torque/compression motor like this one being used with less than desirable performance supporting drivetrain components. The cams you are looking at will make it a turd off the line.. then it will start pulling and make you grin.. then the induction/exhaust(heads) will be done and the car will nose over and kill off most of the potential gain the bigger cam was designed for in the first place. The parts need to match for best results and any savvy engine builder cams the motor to match the parts. Doing it any other way will leave considerable amounts of power on the table. AFAIK.. the z-28 springs are about 260-270'ish lbs open pressure near or slightly past .500" lift. Plus.. they are not high end springs.. they will relax a bit more(5-10 lbs) in short order too. Put the lower lift cam I mentioned prior into this engine and it will be even less open pressure. Why put a bigger .500" or more lift cam in stock heads with a piss-poor rebuilders special valve job where flow falls off and go turbulent at much over .400" lift anyways? Faster valve action and lower lift flow is your friend here. Higher ratio rockers will help there too. Not that I'm condoning gambling with you existing motor here.. but if I too had another motor in the works?.. I'd just install the smaller diameter z-28 springs with Vortec retainers, forget about the pins.. and go have some fun with the car in the meantime. I've done it and I know dozens of others who have never had issues either. Considering the cam/spring pressures/rpm band/engine combo.. the risk is smaller than it would be if you get too carried away here. The simple fact is this. Those heads need as much help as they can get.. especially on the exhaust side.. tighter LSA and extra exhaust duration spread helps improve blowdown(reduces pumping losses) and improves scavenging and inertial tuning of the intake charge to improve peak AND average torque where this car needs it the most. Basically, tighter LSA improves the engine/powerband without the need to overcam it and needlessly cause a narrow and nearly unusable rev range for such a limited parts combo. My bench racing bet of $100 says that the cam I chose earlier ground on a 108° LSA(or even off-shelf @110°) will be faster and funner to drive(more torque/more responsive) than any of the others recommended in this thread so far. Tom's and bmcdaniels would be a close 2nd and 3rd. There is absolutely no way any custom cam grinder would EVER recommend a 112° LSA cam for this engine/drivetrain combo of parts unless the words "docile and absolute highest manifold vacuum needed at 550 rpm" were uttered when the order is made. Their experience and the software they use to help you dial in the combo would warn you away from some, if not all of the cams recommended here so far. The motor needs to be crutched due to the poor induction/exhaust and unless you start tossing money and parts at it?.. the cam is the only way to apply that crutch. be damned sure to keep the headers/exhaust on the small side too. It will help to reduce reversion and iad torque production where this combo needs it most. Here's a low budget parts list I would use to make it an overachiever.... http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=875&sb=2 http://www.speedwaymotors.com/Speedway-Racing-Valve-Springs-1-25-Inch-O-D-Set-16,88.html pic of the smaller/lighter Vortec retainers.. http://www.powerperformancenews.com/wp-content/uploads/sites/4/2015/09/VORTEC-06.jpg http://www.alexsparts.com/locks-keepers-hardened-11-32-x-7-degree-sbc-sb-ford-pont-olds/ http://www.alexsparts.com/11-32-umbrella-seals-viton-sb-chevy-351c-universal/
My comment was not directed toward you personally, and was not meant to be derogatory. I just saw the whole thing starting to snow-ball and moving way beyond the O.P.'s original intent. If someone has the budget to build a high performance motor, then of course it would be foolish to mess with stock heads and the like. 'Sounds to me like a good "RV" cam with new springs is what's practical for this particular application.
