327 sbc build 68 nova
Hey guess brand new member. I have a 68 nova with full manual race built th-350 and ford 9 inch 4.10 gears. I used to want big power(young and dumb) now I just want a street rig and maybe a run at the strip couple times a year. I need some help with my build, when I was a lot younger I bought a race 327 with a monster cam, it is not streetable at all, has not been run in 2 years. Its bored .40 over with a forged crank, hypereutectic flat tops and 2.02 1.60 double camel heads with roller rockers suppoes to be 10 to 1 motor. The plan is to put the comp cams nostalgia plus L79(cam part number 12-671-4) cam kit includes new lifters, valve spings and timing chain with edelbrock air gap rpm and edelbrock thunder series 650 carb and complete mallory ignition with 6al box. Is this a decent setup? ok for street or no? any suggestions? pump gas ok? Also what stall converter should I run? i was thinking 2400 stall?
anything I forgot just ask.
Just me, but I wouldn't buy any parts relying on what its "supposed" to be. JMO I would remove the heads and measure chamber volume, the pistons distance from the block deck at TDC, and valve reliefs volume(confirm they're not domed), and the use the information in one of the online CR calculators like: http://cochise.uia.net/pkelley2/dcrvb6.zip
Besides if it hasn't been run in a couple of years you may want to check for rust on the cylinders, and the condition of the bearings while your in there.
But like I said, thats just me.
sorry should have been more clear. The motor was a long block, before I installed it in the car I popped a head off and yes they are flat top 40 over. The heads are 291 casting so they are 2.02 1.60 with 63 cc correct?. The motor is currently in the car and has been in a garage never below 55. Should I still be worried about rust? It currently has a 750 holley double pumper. The current cam is a howard cam advertised 289 and 294 and lift 488 and 503. power band is 3000 to 6200. Sucks on the street!
Figuring on the piston at .025 in the hole, .041 gasket and 7cc valve reliefs, 63 cc heads, I see your static c.r. around 9.09:1; even at 10:1 with a good tune you should survive good pump gas. Aluminum heads would be more insurance.
Are 291 castings double hump?
Yes they double hump
thats hardly a wild cam.Thats a fun engine.If you dont like that type of power,perhaps a hydraulic flat tappet 350 is better for you?
the car was fun. just sucked on the street. It idled at 1150 and had no power under 3000k. I was told by a couple guys that the cam in it is way to big for smaller cube motor unless I want to run 3500 stall and 4.56 gears
327 does not make much torque at low RPM. If you like torque build a bigger engine,use a longer stroke for lower rpm response
I get that the 327 doesn't make big torque, I am just wanting to make my nova a cruiser that is not slow as hell and I don't want a 350, like to be different. lol basically just wanted to see if I was on the right track to make the motor more street able with a little snap and keep decent sound. My buddy is trying to convince me to build a 406 sbc. Which I would love to do but still don't fill confident enough to tackle something like that.
I like a 327 that revs to 7200 rpm.you need the gears to make the power use able. best bet is a moderate solid lifter or either kind of roller. Flat tappet hydraulic would be my last choice. A 750 carb is perfect
The 283's and 327's were indeed fun motors, I ran a tunnel ram 331 in a 4-speed Vega gasser in the early '70's, in Alaska for years, it would stand on the bumper no problem, but the power came at the expense of high rpm and a lot of broken parts, look at some of Grumpy's old cars beating up on the BB's. And yes, that can make them finicky on the street, the days of side stepping the clutch at 9k are gone, not that we ever did that on the street...:rolleyes: :nono:
You can still have fun with a small cube, reasonable c.r. motor, compensate with gears and match parts.
You could change the camshaft. But the cam that is in it right now is not that radical.
From your discription of the high idle speed and lack of throttle response its clear the motor is not properly
set up.. If you re willing to do a few things, once done this eninge will have a totaly different street manor
and idle much lower and drive much better. It will be much more street friendly.
the ignition timing curve that this eninge needs is specific and requires a bit of modification to get it right.
The carb will need a few tuning changes too. None of it is hard to do but is specific.
DO you want to do that?
What intake manifold?
What rear gear ratio?
What transmission converter stall speed? now
if you want a mild cruiser thats easy just change the cam to a Howards cam # 112571
But you can fix what you got.
If you are not happy with the result you can still change the cam.
You do no need a new carb and the tuning will not be wasted.
If you follow good assembly practice, this can be a very nice combination with some minor head work. See my combo (similar with a version of that cam) and dyno sheets. Note my torque is almost ruler flat for 2,500 RPMs and that's a big power band that works well on the street.
331 CI, pump-friendly 9.5:1 CR
K&N 14"x4" air filter, Corvette drop base and lid
Holley 600 dp, choke horn milled and blended, Primary - 69, Secondary – 74, Squirters - 21
1/2" Aluminum open spacer port matched to manifold, exterior polished
Edelbrock Performer RPM intake manifold, port matched, exterior polished with all extraneous castings and lettering removed
Homemade lifter valley splash shield to keep hot oil off manifold bottom
Manifold heat riser crossover blocked
Camel hump 1.94/1.50 heads hogged out to 2.02/1.60, pocket ported, port matched, pump-friendly hardened seats, 3-angle valve job
Cylinder bores clearanced to unshroud the valves
Comp Cams 1.52:1 roller-tip rockers
Crane Cam Vintage Muscle 327/350 hp cam, 222 degrees @ 0.05, 0.447" lift (with 1.50 rockers)
Doug Thorley headers, dechromed and ceramic-coated
2.5" mandral-bent exhaust (including tips), 2" cross-over just before rear axle
DynoMax stainless Ultra Flow mufflers
Millerspeed 1-1/2” Gilmer under drive belt drive system
Mallory Hyfire IV CD ignition box triggered off Accel points
Mallory high voltage chrome coil
Mallory spiral-wound coil wire
Mallory solid copper plug wires, ends soldered to wires
37 degrees total ignition advance
Carter high volume fuel pump
Melling high volume oil pump
Polished aluminum high flow water pump
Flex fan with polished aluminum spacer
Polished aluminum one-wire 100 amp alternator
Header Power Bracket
Keisler TKO600 5-Speed
3.70:1 positraction with Big Block yokes
225/60/15 Firestone Firehawk SZ50s on 7”-wide Western 30-spoke Turbine Wheels
I ended up ordering the comp cams nostalgia l79 kit. Going to run edelbrock 650 with current air gap intake and mallory ignition setup. I was told by the guy that built it they were the 2.02 heads. Hopefully he didnt lie. Going to run a 2400 stall along with 4.11 gears with trac lock. If it doesnt work live and learn. I still want to build a 406 sbc
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