Looking to build a street machine. 72 CS
355 SBO
Stock crank and rods
These heads (anyone know anything about them?)
http://www.oldsrocketparts.com/produ...-heads-330350/
Edelbrock Performer RPM intake
Stock Q-Jet
Headers
Looking at @ 10.5:1 (Should be good for 93 octane with the aluminum heads, right?)
Comp 275DEH cam

Anything I am missing? On the right track, or way off base? This is my first build.

 

What piston?
Cam doesn't have enough lift to make best use of the heads.
You'll need to open up the intake to match the heads.
And imo lose the Qjet, you can get something easier to tune.

 

my build.

355 with speed pro flat tops, 10 to 1 compression , lunati voodoo cam 522/539 lift 233/242 duration , # 6 heads with just big valves ( no porting), Prw ford full roller rockers, RPM intake, pro gear timing chain, 750 holley DP ,

pretty basic combo street driven and driven to the track and back about 120 miles round trip.

so far 12.20's was shooting for 11's with a 3500 stall. But traction issues became a problem now.

 

Pistons would be the SpeedPro flat tops.

If I went with a 1.7:1 rocker on the intake, would that produce sufficient lift or not?

 

Maybe, but using the right grind would be better.

 

OR....I could go with this rod
https://www.summitracing.com/parts/s...021a/overview/

and this piston
https://www.summitracing.com/parts/slp-h616cp/overview/

and build a 362. Here are the potential specs.
CYLINDERS 8 BORE 4.125 in. DISPLACEMENT 361.9 cid STROKE 3.385 in. PISTON HEIGHT 9.3175 in. ROD 6.200 in. DECK 9.33 in. COMPRESSION HEIGHT 1.425 in. COMPRESSION RATIO 10.112 :1 HEAD VOLUME (cc) 64 cc DYNAMIC COMPRESSION 8.094 :1 PISTON HEAD VOLUME (cc) 6.400 cc HEAD GASKET BORE 4.155 in. GASKET THICKNESS (COMP.) 0.037 in. QUENCH 0.049 in. PISTON/DECK CLEARANCE 0.012 in. CAM-COMP 275DEH INTAKE DURATION 219 ⁰ @ 0.050" INTAKE ROCKER ARM RATIO 1.7 :1 EXHAUST DURATION 233 ⁰ @ 0.050" EXHAUST ROCKER ARM RATIO 1.6 :1 INTAKE CENTER 105 ⁰ OVERLAP 6 ⁰ LOBE SEPERATION 110 ⁰ EXHAUST CENTER 115 ⁰ INTAKE MAX LIFT 0.505 in. INTAKE LOBE HEIGHT 0.297 in. EXHAUST MAX LIFT 0.507 in. EXHAUST LOBE HEIGHT 0.317 in. INTAKE OPEN @.050 4.5 ⁰BTDC ADV. DURATION INTAKE 275 ⁰ ADV INTAKE CLOSE 63.5 ⁰ABDC ADV. DURATION EXHAUST 277 ⁰ INTAKE CLOSE @.050 34.5 ⁰ABDC ADV. OVERLAP 2 ⁰ EXHAUST OPEN @.050 51.5 ⁰BBDC EXHAUST CLOSE @.050 1.5 ⁰ATDC Note: 5 degree adv.

 

Yes you could.
But a couple of things;
It's still a crappy piston with a big fat ring pack, just the facts.
Conversely, way overkill on the rod. An I beam with 7/16 bolts would be a better choice. But either way, the small end of the rod will most likely need to be machined on one side as Chevy rods are offset, Olds rods are centered.
And I'd check the heads to make sure they really are 64cc.
Hope this helps.

 

Thanks. Still doing research as you can see. I am more interested at this point in finding more info on the heads. If they are not as advertised, I am back to square one and will be forced to recondition the irons I have.

 

Not necessarily. Any of the aftermarket heads can be cut to 64cc or even less with no issue. You just have to check them first.

 

https://www.summitracing.com/parts/dms-6020x-4080# Ignore the Canadian dollar amount, our dollar sucks lately.
These are a better piston than the Speedpro. They have the small valve reliefs at 3cc and also available in the 4.065" and 4.100" bore. Mark's piston are more aimed at giving reasonable compression with iron heads. The Mahle piston sounds extremely nice but you need a small dish to take advantage of the better aluminum heads.

 

Hmmm not entirely true. Again the aluminum heads can be cut all the way down to 50cc. Plus the Mahle will have an even better ring pack, and full coatings.
But it's good to know I'll be able to compete with that price once you include the rings.

Thanks!!

 

True Mark and very good option but the intake will definitively need cut. I just need to find a spare 350 block, my current one is in good shape.

 

Cutting the intake is really not a big deal. When it's right it's free hp.

 

Back to your original question, can you spin a 355 above 6,500 rpms. Yes but why would you want to? Stock rods=living on the edge. Iron heads=limited. The only place I could ever see near 6500, with stock rods, would be in the traps. I know everyone has a love affair with rpm's. I'd try lower shift points first, looking for the fastest times. Jmo.

 

The 350 will make the most power up top. On my current 355 I shift at 6700 and it hits at 7k. I set the light for my reflexes. Albeit my engine will breath up there but I'm still on stock rods and crank. I hit the traps @ 6k but I have a 3.90 I really need a 4.56 I have tried shifting lower like alot of people have said and it's just not the case in my experience.

 

Yeah, Copper your motor has held together really well and you have the heads and cam to support the higher rpm. Do you even have ARP bolts? Since this thread was started, things have changed with the small chamber Edelbrock heads soon coming out. My bottom end should easily take 7K but the rest will depend on Mark's recipe for 91 octane. I will probably still have to have a clean up mill on the intake to make sure the thicker BBO intake gaskets will fit.

 

I do have ARP bolts through out and the machine shop that did all the machining does R&D work for dart and other vendors so when I checked everything it was right where everything needed to be.

 

Quality machining no doubt helps alot.