Greg,

Should that be 18* of overlap at .050?

Greg,

That's certainly part of it....but just because you have an overlap "constant" that doesn't take into account the differences in cylinder pressures and pumping efficiencies that the 2 different cams can/will provide, both at part throttle and WOT. To my thinking the 505" motor will benefit more from a larger 236 degree intake lobe, even if it doesn't see as much scavenging benefit from the overlap cycle (since primarily the small exhaust/blowdown is likely to limit its effectiveness at the upper part of the torque/hp curve).

I've always found with street strokers (where roll-on part throttle torque is more critical than optimum top end power...ie, 90+ % of cars driven on the street...you generally want as large an intake event as you can get without hurting torque at the lowest part of the DESIRED POWERBAND (for the load and gearing the motor sees). A 228-ish event with a tighter spread will come in ~500rpm sooner but will also be done and fall off proportionally sooner as well (for a given head flow and compression), as someone said that would be a Truck/RV style curve, or what I call an Oldsmobile curve (Tractor like torque off the line but basically all-done by ~5 grand). A Jensen would weigh about the same as a typical well optioned B body, IMHO the 236 lobe will give a 10:1 500" motor just about the perfect all around balance of smoothness, predictable roll-on power and still a decent and respectable top end rev ceiling that will feel proper (and most of all) FUN in an Interceptor.

Yep! I knew I should have taken that nap,,,,,,,,,

I have those SS block hugger headers too. I bought them originally thinking of running them. Maybe I can test them when I dyno the engine? For not much money, they actually look pretty good.

I'll see if I can dig up a video of the Coronet. I know I have one of the car at idle, but it was when I had the RPM intake not the EFI. The car has a lot of torque, I lug it around at 1,500 rpm. It has a 5-speed manual trans, and 1,500 rpm is about 50 MPH in overdrive.

I have a video on youtube of the convertible at idle.

https://www.youtube.com/watch?v=0ui4GCHn_7o

My Convertible has a 505 with the -17cc pistons, I think around 10.3:1 compression with stealth heads and a Comp Hydraulic Roller cam XR286HR-10 #23-712-9, 236/242 @ 0.050", 0.544"/0.541" @ 1.5:1 rocker ratio.
TTI 1-7/8" headers and 2-1/2" TTI X-Pipe exhaust with the super turbo mufflers that come with the TTI system. This is when the car had the RPM intake and Holley 770 cfm ultra avenger carb.
I don't know it this video was when the engine had the CAT 1.7:1 rockers or the 1.6:1 Harlan sharpe rockers that replaced the junk CAT rockers.

Those 511 strokers SOAK up cam --too low duration at 050 and wide LSA it will sound like a milk truck
Don't over think this--like the wise say 230 ish on a 110 should be very gentle enable all your vacuum needs by far and I bet it will soon toss the Jensen rear out in the street--go with that crazy wide LSA stuff and you will hate the way it sounds
That car and combo is begging for some quality muffler experimenting--with a mild cam combo you can re-gain that sexy sound if you drop serious cash on well engineered ( expensive) mufflers Think Italian car here We messed with an MGA all summer one time and after about the fifth muffler it sounded like we had an Exotic and we never touched the stock engine--there is some very beautiful sounding equipment out there--Mufflers are the last thing we get and least thought put into them--yet any exotic car makes your blood pressure go up all because they spent the effort on entire exh system simply look at new Mustangs etc to see Detroit looking into this
Just my two cents
Folks spend 90% of engine building on that cam and 10% on the rest--my fastest race car has a cam that came out of a 5 gallon bucket behind the door of my machine shop and was used because it was free--speced out way too little per all the conventional wisdom and turns out it is the best race engine I have ever had for $$ spent ( or lack of )

I agree, pretty much what I was thinking.

not a roller but it does everything you are asking for ..... hughes seh3236bl3-14 installed on 110 c/l with a 114* lobe sep.. w / 1.5' s .536 in. .546 exh. -- the dur. is 232 intake. 236 exh. @.050 mine is 10-1 comp with 915's 16* initial with 36* all in by 2500 rpm... and iron hp manifolds to boot..

Thanks for posting the vid.
Sounds just about right (in neutral), but I'm thinking that with an auto in Drive with a stock-ish converter @ 700rpm, it might be a little much for my situation.
So I'm thinking a single pattern in the lower 230s or a 230/236 cam might be just the ticket.

Although this seems a little small, considering your choices in the carb and intake, and the likely exhaust system, this is probably about right in my book.

About rockers:

How do I know if I have the HD stamped rockers or the regular ones? My motor is an HP motor, but I don't know if they automatically came with the HD rockers.

Are any of the stamped rockers going to be reliable with a cam around .550 lift and beehive springs?

I bought some 1.6 PAW aluminum roller rockers on clearance, but I am starting to have second thoughts about that after reading so many horror stories about aluminum roller rockers (other than the super high dollar ones.) I am also concerned that a .550 lift cam with 1.6 rockers may put a lot more stress on the valve guides causing them to wear out too quickly.
For this car, I am looking more towards long term reliability than to a few extra HP on a dyno that this motor will never see. Of course, everything is a compromise when you're looking for more power, but this motor needs to be just that...a compromise between some nice power and some docility and reliability.

I don't know anything on the PAW rockers?
Nothing wrong with aluminum rockers, I have Crane, Harlan Sharp and T&D aluminum rockers on several engines with no problems. It seems higher valve spring pressure is tough on the rockers and valve train. A small hydraulic cam with Beehive springs is going to have fairly low pressures, so it is easier on what ever rock you use.

Hopefully someone with the PAW rockers will respond with their experience, but I'd use them.

I think all the factory rocker arms were the same? I hear the Mopar performance replacements were made of thicker steel?

If you want to idle nice at 700 rpm, I'd use a step smaller cam like the Comp 280HR-10 (PN: 23-711-9) maybe even have it ground on 112 LSA to reduce overlap? This is where I would be talking directly with the cam grinders to get their advice.

On the rockers... as a rule of thumb the stamped rockers are OK up to .5" lift with a FT profile and moderate matching springs. I would surely avoid the PAW AL rockers.

A mild FT cam and stock stamped rockers would work fine and be very budget friendly.

If you go more than that, higher end rockers are really important to get a reliable result... and also not trash your nice new engine. I like and run the Comp cast steel alloy "pro magnum" rockers at .55 lift. The Hughes aluminum rocker is supposed to be good as well in a moderate application and not crazy expensive.

I made a mistake...they are PRW rockers, not PAW...but probably the same difference, though.