SS 350 Rebuild

[Jaydv]

Timing chain gear teeth busted and I have to rebuild the motor.  Numbers matching car so a crate engine is not an option.

Would prefer to keep it as close to stock as possible but, while it's apart I thought I'd go for a little sexier cam along with roller rockers and lifters.

Thoughts/comments would be appreciated!

[69Z28-RS]

Roller cam is a good idea as it will reduce internal friction (more usable hp).   Choose your cam specs and rockers carefully.   the wrong cam can turn your very drivable engine into a 'pain'.  I've personally had 'troubles' with roller rockers, where the 'locks' come loose on the highway disabling the vehicle...   I've used 'friction nuts' since on every rocker...

[x66 714]

If that's the "born with" engine make sure the rebuilder doesn't deck that block. The almost all want to do it to make extra money....Joe

[z28z11]

Why not build a "driver" long block and shelve your original ? Plenty of 010 4 bolt blocks around, for cheap, or a crate engine dressed to appear as a period '69 SS350 ? Unless you're looking for show judging with an all-numbers car, it makes sense not to expose your vintage and correct matching numbers drivetrain to wear and tear on the street; restore your original at your leisure while enjoying your SS -

Regards,
Steve

[Kelley W King]

The 327 350 horse cam sounds good and very street friendly. Put 2.02 valves with it and have some fun.

[ko-lek-tor]

1.94 valves will give better street performance. Roller rockers will most likely not clear stock valve covers. I’ve had bad luck with flat tappet cams of late eating lobes. Go for a roller

[z28z11]

The 327 350 horse cam sounds good and very street friendly. Put 2.02 valves with it and have some fun.

I second that nomination for a camshaft. Great idle, good vacuum, hydraulic lifters. I ran one for many years in my .040 over 283 Bel Air with 1.94 heads from a '63 327-300 horse motor, 11.0 to 1 pistons, ran as strong as 327 and 350 cars with a lot more cubic inches on board. Holley 3310/780, Edelbrock C3BX manifold, Thorley headers, probably more carb than needed, but it got great mileage and never a minute of problems. First engine I built, loved the idle sound -

Regards,
Steve

[Stingr69]

Roller cams are nice but they do cost a lot.  You are looking at about a $1000 total upcharge by the time you are done to do the conversion.  EVERYTHING is required to be upgraded.   

An overhaul with a stock 327/350 or 350/350 cam would be an easy choice.


Another idea -  GM LT-1 350/370 solid lifter cam is not really difficult to live with and they make special solid lifters with EDM lubrication holes on the wearing faces that prevent the cam from going flat.  No special rockers required. Howard's Cams sells a 350/370 GM copy cam/lifter kit with these special EDM lifters included.  That would really sing. 

[z28z11]

I forgot to ask if the SS is a manual or automatic - that would have a great influence on camshaft selection, piston selection and everything else. You can still get a complete 350 master rebuild kit for decent money, add the machining costs (and assembly if you have the need), and you're all set. Solid lifts can be a bit radical for automatics - idle speeds and vacuum limitations. The L79 cam would be a good fit with a 350 Turbo or Muncie/Saginaw -

Regards,
Steve

[firstgenaddict]

you have to match the Cam to the flow of the heads and take into consideration velocity of the intake charge, which relates to piston speed, and flow numbers on the heads ( runner cross section / Runner volume CC)... higher velocity allows the cylinder to continue to fill even after the piston is no longer descending - engine builders often refer to this as  CRAMMING...
CRAMMING - when the piston has stopped descending and dwelling close to BDC  - it begins it's upstroke but the intake valve is STILL OPEN and the cylinder is still being filled due to the velocity of the column of air.

Slapping big heads or the wrong cam in/on an engine can kill the performance or catapult it into next year.

[upscope757]

Some thoughts. I started with the intent of restoring to exact originality an RS/SS '67, 350 block, though I did not have the original engine. I found a correct engine for the powerglide, smog car as mine was out of CA. (Car VIN: ~17k, Nov '66; eng VIN: ~32K, Dec 66 - both from LA)

Push rod started to pop off the rocker and wear a bit on the head so I chose to go the roller rocker route, upgraded heads, 2.02 valves, etc...

From my experience I offer the following...

1) I was mindful of the 2-bolt main and showed some concern of building too much power into the engine. Roller cams can equate to higher RPMs. Stronger springs needed, etc... but 2-bolt mains operating above 6,000 rpms is risky business IMHO.
2) Roller rockers would require taller valve covers
3) Consider screw in studs/valve guides
4) For roller cams.... please be mindful of one thing if nothing else... gear at the bottom of the distributor must be changed to the softer brass gear. The factory steel gear will chew that camshaft up.
5) There is also the spacer (actual name is escaping me...) at front of the cam that needs to be installed to keep the cam from walking out of the engine. I pulled my timing cover off and saw the witness marks on the back side of the cover even though I had it installed. I ran the original '67 block for awhile, then...
6) Attached what is sitting in the car now. 383 stroker, 10.5:1, roller rocker/roller cam, 2.02 valves, alum heads, screw in studs/valve guides, dual quad - 2x500cfm.
7) The original SS350 engine is garage art, sitting on an engine stand next to the car.

Anyway... remains fun. Just something else to think about.

[upscope757]

Regarding 5) above, I think it is called a cam 'button'. Memory still fading a bit...