Hot Rod Forum banner

327 sbc build 68 nova

6K views 27 replies 7 participants last post by  vinniekq2 
#1 ·
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.
thanks
 
#2 ·
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.
FWIW
ssmonty
 
#3 ·
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!
 
#13 ·
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 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!
No, they may be 2.02/1.60, but can also be (and more likely), 1.94/1.50 valves as both were used in these castings.

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
Champion plugs
37 degrees total ignition advance
Carter high volume fuel pump
Melling high volume oil pump
Open breathers
Polished aluminum high flow water pump
160-degree thermostat
Flex fan with polished aluminum spacer
Polished aluminum one-wire 100 amp alternator
Header Power Bracket
Keisler TKO600 5-Speed
Hurst shifter
3.70:1 positraction with Big Block yokes
225/60/15 Firestone Firehawk SZ50s on 7”-wide Western 30-spoke Turbine Wheels



 
#10 ·
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.
 
#12 ·
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.
 
#14 ·
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
 
#15 ·
The cam I ordered is not alot smaller no, but the lobe seperation is 112 vs my old cams 106. So I know that will have a pretty big effect on getting going. Should move the powerband down also correct? Yes i understand I will give up peak power for a flat power band. I know the cam powerbands are based on a 350, which according to comp cam is 1800-6200 for the l79 plus. So I figured 2000ish for the 327? That why I said 2400 converter? Correct me If i am wrong. It is still not to late to cancel my order.
 
#16 ·
Why would I need a 3000 stall?
It has a 2000 stall from my old 350. I know that is wrong for the motor, i didnt know any better back then. I guess when you say re-tune I dont get what you mean. motor is set at 16 degrees and total timing is 36 around 3500ish?

I was going to get a 3500 stall and 4.56 gears or 4.88s, but want a car that I can drive, not run at the strip.
I hate the holley double pumper i was always messing with it.
 
#19 · (Edited)
68'nova, I got a similar cam to you, prolly bit bigger, in a 350
Some of my mates got similar and even bigger cams in their sbc's and they got fumey rich idles, fouling plugs, rough idles etc etc. Real PITA to drive on the street.
When I built my latest engine, I followed F-BIRD'ss tuning recommendations (locked out timing, yada yada) to the 'tee' because he sounded like he knew what he was talking about, and he does... Mine idles smoooth, clean like a taxi cab, rock solid @900 rpm, even down to 700rpm with a bit of shake , super responsive , goes like stink, yet my mother could drive it to go grocery shopping. Well, not really, cause she would poo her pants, but you know what I mean. I'd stick with the cam you got, mine has REAL good street manners the way it's 'set-up'.

Hope this helps, FWIW

Duke
 
#27 ·
I have 4.10s right now(already said that) and also said I wanted a mostly cruiser with with few runs on the strip. I am going to try the lock out timing and see what happens. I called mallory they can make my dizzy do 10 degrees mechanical advance if I have too. Also they make a start retard box for under 300.
 
#28 ·
I know you have 4.10s,I read that already. I dont think you need to be that aggressive with the distributor with that little cam. I would first try the idle settings with the timing at 18 ish initial. I run 18 at idle with a bigger cam,but I do need a little more.I just have my total capped at 34 for now. You can do the same and test drive with pull power pulls set at 34 degrees and 36º to make sure there is no pinging.
If after doing both tests you will know where the static needs to be and where the total needs to be.Simple,pull distributor and find someone with a distributor machine.
with 4.1 gears the actual time spent at wot and under 3,000 rpm is short,so your part throttle tuning is all you need to worry about. The 2400 rpm converter means that the only part throttle rpm range is 2,000 - 3,000. At full power acceleration its only between 2400 rpm and 3000 rpm that you have to worry about ignition curve. If you race the car a lot,then maybe invest in a race converter.
I would spend time on the carb and fine tune the A/F ratio. you pick the numbers you want,IE; 13:1 at wot for good power,good plug life and perky acceleration,or 12:1 at wot for more power but not as good plug life and not as perky at part throttle.
If you tune on a Mustang or similar dyno you can tune the car for both.
You would do this by making primary throttle runs(disable secondary linkage) and tune for 12.8-13:1 a/f then make a few pull with the secondaries re attached and aim for 12:1 a/f
you might drive the car awhile then go back and retune again.Its not always maximum power that makes the best driver.You want to enjoy all parts of driving the car.The street driving is 98% of the use you will have for it.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top