As I gather parts for my (eventual) engine build, I'd like to get some thoughts/input regarding my decisions and direction. Goal: Solid, sturdy engine that makes good power & sounds mean, and also looks totally bone stock on the outside. The car ('78 Regal) will be a summertime cruiser/hot rod. I have no intention of building a high-RPM 1/4 mile bruiser, and likely won't put in on a drag strip even once. For what it's worth, the engine will be mated to a 4 speed manual trans, and behind that a posi rear with around 3.42 gears. The "definites": - '71 350 block, bored 0.040", all oiling mods, grooved cam bearings, double roller timing chain, turned/polished/balanced crank - 3.0L flat top pistons (obviously also 0.040" over) on resized/polished capscrew rods, placed in the hole to net 10.6 (give or take) static compression - '71 350 iron heads, home ported & polished, 1.92"/1.55" stainless valves, TA Stage 1 springs, HD stock 1.55" rocker assemblies, TA lifters, stock valve covers - ported iron exhaust manifolds - TA dual plane intake, port matched, properly built/jetted Quadrajet carb - typical timing cover with oil mods done, oil pump booster plate - HEI distributor, MSD ignition The "not-so-defintes": Cam: I just don't know! What I do know is that I won't be going the hydraulic roller route, and am currently considering a (now obsolete) Crane Cams 710631, which I've attached the cam card from. I know there are a lot of variables when it comes to cam selection, some of which I don't have available (i.e. head flow numbers), but on the surface, what do you guys think about this cam with my proposed setup? Are there any other off-the-shelf flat tappet cams that might be a "better" choice (the TA 310 is always in the back of my mind, for instance)?
afaik, the 3.0 pistons have a really short compression height and will only give about 9.5:1 in an un milled/decked engine. i'd go with the forged autotec pistons. piece of mind, plus you can run nitrous and not worry too much.
Get the head flow number then contact Scott Brown about a cam. 10.5 seems abit high for compression for that cam and for iron heads .
The 310 is a good cam and performs well along with the TA 290-94H. TA 284-88H is probably the most popular higher performance cam we sell for the 350. It wont make as much as the other two cams, but it will do a little better down low.
The compression height on the 3.0L pistons is 1.808", so unless I'm missing something they would sit 0.067" in the hole with a stock height block (10.185" deck height - 1.808" comp. height - 6.385" rod length - 1.925" half of stroke), which would net around 10.6:1 with a 0.020" head gasket, and around 10.3:1 with a 0.040" thick gasket. NOTE: I'm very well aware that I cannot assume the deck height to be "correct". I'll definitely look into Scott Brown. I'm certainly not opposed to bringing the static compression down a bit, but I want to make sure I keep it high enough to use a "mean" cam and not make the head work/big valves be in vain. Thanks for the response Mike. All 3 of those cams have been very much on my radar for quite some time now.
You will probably need to mill .023-.025 off block to get those pistons around.067 below deck. i do have the 284-88 cam in a 430 with fuel injection and a tight 2800 converter. Definitely plenty of power. my 350 car has the 310 cam. Advanced 4 degrees. About 9.9 compression. 3200 converter. It sounds throaty. But will see how it pulls when it gets warm.
That Crane cam has a lot of duration. Probably won't work power brakes. Spent a little more for good Auto tech pistons, they are worth it. Crower level 3 cam will make great power, gets good mileage, works power brakes. It won't go lump-lump-lump and load up at idle.
Yes you are in the right track and no need to mill the block with those pistons you will have e a good compression ratio. Order a custom Scotty Brown cam it’s no extra $
If you have that Crane cam, I would run it. I ran this Crane back in 1998. 14 flat in 1/4, street radials, turbo 350 tranny, 390 gears. 750 Holley, headers, TA dual plane. A bit smaller grind than yours.
In my delusions of grandure 15+ years ago I tore the engine down to get machine work done, (but as a 19 year old kid I ran out of money REAL QUICK) and I may have had the machine shop deck the block. Hopefully within the next couple weeks I'll have a chance to put the crank back in it and hang 4 pistons on the corners to verify the actual deck height, as well as verify that it's square. Lump-lump-lump is a good thing, and if I have to add a vacuum can for the brakes that's okay. Gas mileage is of no concern for this build, but I'll definitely look into the Crower cams. I don't currently own this cam. But there's one BNIB available, and because the price would've been about 50-60% of what most new offerings are I was thinking about pulling the trigger. Deep down though, I wasn't quite a fan of building a fresh engine using an obsolete cam.
Decide what cam you want and buy it new, you don't know exactly what kind of shape a used cam is in unless you mic the lobes. Don't cheap out, spend the money on new quality parts, or else you'll just end up with spare inferior parts. Ask me how I know. I gave JW at TSP all the info on my car and he had a custom one ground for me. Keith
The DCR for that cam and 10.6:1 SCR will be 8.35, pretty much Race Gas Territory. The .040 head gasket would make the SCR 10.2:1 and the DCR 8.00. That is installed at 108* ICL.
Autotec pistons can do custom compression height if needed. Go for zero deck height and .040 gasket, then let Autotec know how much pin relocation you need. Consider the dynamic compression ratio for the package as well.
Too much compression and too much cam is going to make a gutless, expensive turd to actually use and drive. The people who are impressed by rough idle at the Dairy Queen don't matter enough to suffer through the poor driving manners. Build the engine to RUN, and if you need to, ground one plug wire a block away from the drive-in so it idles crappy enough to jack-up the yokels.
Too little compression and too much cam makes a gutless engine. Too much compression and too little cam make an engine that does a cheap imitation of a diesel. http://www.empirenet.com/pkelley2/DynamicCR.html
I posted this a while back, but they keep sending me the same promo code. It's worth a shot if your ordering from AutoTec it could save you some cash. http://www.v8buick.com/index.php?threads/racetec-autotec-piston-deal.344199/ I'd square up the deck and get an accurate height before ordering customs. Just a heads up if you decide to order from Crower. They may have stock cams on the shelf ready to go, but if you order a custom grind like me (through TA) its going on 7 weeks for my roller. I know you said you're going flat tappet but at least ask about availability if you plan on doing it soon.
