Hi new to thread. I have a 89 custom cruiser and i cant decide on either putting in a olds 350 or 455. I want it daily driver but more get up than the boat anchor 307. Found a 350 and here is whats done to it. Any feed back on this engine would be appreciated.... Oldsmobile 350. Rebuilt with .030 over sealed power coated flat top pistons. .488 lift RV camshaft. #8 heads with 2.00 intake and 1.62 exhaust valves

 

The 350 is externally identical to the 307, so everything bolts up (accessory brackets, valve covers, exhaust, etc). This is a bolt-in swap that you can do with your eyes closed. The 455 is ALMOST as easy, but the taller deck height requires some mods to the accessory brackets, exhaust, etc, and the valve cover clearance to the HVAC box is tighter.

The flattop pistons with #8 heads actually gives you a decent CR. Your 89 used a roller cam 307 with the peanut-port 7A heads, so while they will bolt up to the 350, you do not want to use the A5 intake and tubular stainless exhaust manifolds from the 307 - the port mismatch will disrupt flow and negate any performance improvement. Get the cast iron exhaust manifolds from any 1980-84 307 with the 5A heads. These will bolt to your current exhaust system if you are planning to retain it. Use either an A4 intake or a aftermarket. Use the 307 valve covers for clearance (they are slightly smaller than the 350 covers) and the 307 water pump for your application.

 

Welcome to the site... As Joe said, the 350 is an easier swap then the 455... Although both are good options depending on the amount of work/effort/money you want to invest...

 

Welcome to the site. While the 455 is very enticing, you'll probably also need a transmission that can hold up behind it. If money is no object, then there is no replacement for displacement.

 

Thank you Joe for your input, Im going for a muscle wagon... I want to do shorty headers, and i want all i can get exhaust wise. My car is exempt in tx for emissions so...... Will the rv cam give it a choppy or lopey sound... Obviously im not to inclined on engines. I was quoted around $6500 for a 455 installation. I just worry about parts for it in the future. The trans is the 200r i was told it could handle the 455.
Thanks

 

Parts for a 455 will be no harder to find than for a 350. Based on what info did they say the 200R will handle a 455?

 

Hi Olds.... That the gearing could be changed...and some older olds had that trans with the 455. I just want a loud tire smoker with torque lol.

 

"RV cam" is like "3/4 race cam" - what are the specs, exactly. Most "RV" cams are designed for low RPM torque in heavy vehicles (like, um, RVs...) and thus will NOT have a lope at idle. In fact, most are as mild or milder than a stock cam.

In stock form? Yeah, to the end of the driveway, maybe.

 

Wrong. The 455 went out of production in 1976 way before the 200R4 came into production.


You will need to spend significant $ on the 200R4 to have it last behind any BBO.

 

Get the 350. The 2004R will need some upgrades to last even behind that 350.

 

I know the carb and distributor are comp controlled will this be a issue? I want to keep the ac.

 

You can run the 350 on the CCC system, but the biggest problem is that you cannot alter the timing at all without burning a new PROM. I'd switch to conventional carb and distributor. The only effect on the A/C is that the CCC system temporarily turns off the compressor clutch at wide open throttle to gain a little more usable horsepower. You will lose this feature, though you likely won't even notice with the more powerful engine. If you do want to disable the compressor at WOT, just rig a switch on the accelerator the way the 1977-1984 cars did.

 

Joe i can't thank you enough..... And like cutlass said will i need to build up my 200-4r to handle this 350?

 

Here are my observations:

That .488" lift cam sounds a bit larger than a typical "RV" camshaft - more along the lines of the UD cam in my engine or perhaps the Engle/Mondello JM-18-20.
JM18-20 = 0.488"/0.496" lift, 260°/266° advertised duration, 216°/226° duration @ .050" lift, 112° LSA for comparison to the UD cam in my signature line.

Not really. It should idle very nicely with only a slight lope. You have to get fairly large on the duration in order to get a choppy idle, then that necessitates high compression, high stall converter, low rear gears, etc.
Don't go down that road.


You're on the right track as low end torque is what you need. As I posted above, a cam with that "choppy idle" requires a lot of additional work and matching components, and without matching all of the components it is very easy to over cam the engine and have poor performance. With the compression ratio and camshaft mentioned it should run well.

 

Thank you Fun71... I just talked to the guy selling the engine and he said this "Adv. duration is 284-284 and .050 is 218-218. Should not need a stall.