I reached out to the company who made the kit and they asked if I would like to exchange the camshaft for a different one here are the specs: Duration @ .050": Intake: 231 Exhaust: 231 Advertised Duration: Intake:288 Exhaust: 288 Valve Lift: Intake: .512 Exhaust: .512 Lobe Separation: Intake: 106 Exhaust: 114 Would this be a more adequate cam or should I just overall go for the cam listed above I would hate to run into ptv clearance. And I will look into the head gasket thickness for you!!! Thank you all
I've got Canfields on my 331. The raised ports (.400) aren't a problem. And just me, based on the problems I ran into trying to run a thinner "high Performance" head gasket when I first bolted these heads on a roller 5.0, I wouldn't mill anything more or use the thinner gasket with an aluminum head on an iron block. For me the tried and true Felpro 9333 sprayed with Kopper kote just plain works, even when the temps shoot up to 250-260* when I forget to turn the fan on. I had my heads milled .060 initially to get the chambers down from 64 cc's to 57 to run on that roller 5.0. After a month and a half, the gasket blew when it got too hot.
I doubt you'll have any PTV issues with either cam. Unless you happen to get heads with a 2.02 intake valve, then you might due to the larger diameter valve. The SP valve reliefs may not clear a 2.02 valve
Thought I remembered you having those heads and using standard port location headers. The Cometic MLS gaskets won't go away or lose the fire ring like the 4.100" felpro rebuilder's will. Plus they're good at keeping compression up with their 4.030" bore sizing and can be reused due to all stainless construction. Hands down one of the best ultra high performance gaskets being produced today. Overkill for this deal but compression and squish velocity is a very good thing to have with pump fuel. The less crevice volume the better too. That cam is better than the other by far but just keep in mind that thing will seem bigger on a smaller shorter stroke motor. Will easily make power past 6,500 and zing to 7k without dropping over a cliff. Personally, unless you're going to have pretty short gearing and want to give up some low speed torque in trade for more topend?.. I'd keep seat timing under 280 and @.050's somewhere's around 225 tops. Will make the motor feel bigger while still revving pretty decent and making more average power for the street.
Right.. they're 1.605" compression height and a 8.200" deck height should put them .005" down the hole.
I would hate to give up some low end torque for top end I do like having the ability to burn the tires off the light haha. Would that second can I listed take away from that?
What transmission and what rear gear you run will be the biggest factor to staying in that cams sweet spot. Yes it's a decent sized cam for a 302 inch 3" short stroke motor. Dual plane will help throttle response some but likely still won't start coming up on the cam till about 2,400 rpm or so. If you want more throttle response and low speed torque stay 270 or under on seat timing and around 218-224 @.050".
For the transmission I am going to be running a world class t5 and as for the gearing I am not to sure I believe it has the 8” rear end? Haha I will be running a 4 barrel carb and a dual plane intake are there any other tips and trick to keeping low end torque up? This is all very helpful, one thing I didn’t get done at the machine shop was have the rotating assembly balance but I just read that that is almost a mandatory thing when you spin 302s high reving so looks like I will be doing that... does it really make that big a difference?
If you're going to beat on it a lot, then yea, by all means have it balanced.Better check to see what ratio's in that rearend too. Although I think that T5 has a pretty low 1st, you may be OK with a 3.00-ish rear ratio, many might take issue with that and push for the ultimate lowest ratio in 1st (the combined ratio of the rear + 1st gear) but doing so can leave you with a 1st gear that's all but useless. The instant you nail the go pedal, you're almost immediately tach'd out and 2nd gear ends up doing the work 1st should be doing. My Comet's got a 2.78 1st combined with a 3.50 rear and 26" tires and it tachs out very quickly when you nail the pedal and the tires are spinning.
Good to know, I have 4.10 and 3.50 for mine and was leaning towards the 4.10. I loved that gear in my Pontiac but it was an auto so it wasn't too big a deal when it rung out in first.
Does anyone know the weight of stock piston, rods, etc from a 71 302 block? Can’t seem to find them anywhere and the machine shop has since tossed them...
Stock cast pistons usually have steel reinforcement gussets cast into the pin bosses and longer 3" length pins.. so quite heavy at well over 700 grams complete(piston+pin and no rings). Rods are shorter 5.090" lengths so on the lighter side at around 550'ish depending on balance pad thickness. 289 rods at 5.155" length would only be about 8-10 grams more. Not sure about weights for your new pistons(check spec's or the mfgr will know) but I'd guess slightly shorter 2.75" pin length and overall weight will end up at least 50-75 grams lighter than stock. Remember though that pistons/pins are only figured at 50% balance factor because they are considered reciprocating weight.. not factored at 100% like rotating weight so not as big an impact on final bobweight. Chances are very high you'll end up overbalanced and the stock type harmonic balancer will never fully do its job at correcting vibrations. So, IMO.. unless you're tossing together junkyard parts and dirt tracking the car till it blows up(just my funny analogy).. it never pays to fork over hard earned cash just to toss stuff together and call it "close enough". If you're already doing it at least halfway right?.. spend the extra 200-300 to have it all balanced up correctly. Overbalance can help at very high rpm but is harder on bearing life and contributes to low rpm vibration.
