I'm finally getting around to putting together the engine for my Imperial. It's not a high-zoot almighty power house but it needs to fit the application.

That application is a 440 powered 5300 lb land yacht with a 727, 3.23 gears, and 29" tall tires. It needs to be able to cruise anywhere I care to go and will need to survive on 91 octane.

This is the first time I've built an engine for this kind of application and I'd like to know if I'm pushing things a bit too far.

Here's the parts I've got on hand:

Eddy Performer heads (early production).
Icon flat top pistons
Stock block, crank, and rods
Cometic 0.027" head gaskets
CH4B intake (possibly swapping to Performer 440) - no hood clearance for a Performer RPM
Carb: TBD. Will likely change to throttle body injection after the engine is installed.
Headman 1-3/4" mid length headers with 2-1/2" collectors and 2-1/2" dual exhaust

I measured the assembled piston height, combustion chamber, and all other bits involved. This presents me with 0.036" quench and 10.2 compression.

So good so far.

Now for the cam. It's a highway cruising stick ground for heavy torque to get this beast moving and hold it there climbing hills at highway speed.

Duration @ .050" 218 - 218
Duration @ .006" 261 - 261
Gross lift .463" - .463"
Separation 110
Intake open 3 BTDC close 35 ABDC
Exhaust open 43 BBDC close 5- ATDC

This little stick should purr like a kitten (and bore you to sleep with the exhaust note) while making good vacuum and working from 1500 to 5000 rpm.

Will this little guy make too much cylinder pressure?
Will the aluminum heads and quench work together to reduce the chance of detonation?

If I have to run the timing back a little to control detonation will I be giving up more efficiency (read: torque) than I would by reducing the compression with a thicker head gasket?

I don't mind it being a premium gas engine as long as it delivers the performance I want. My wet dream is 500 lb/ft down low and maybe, just maybe 400 hp around 5200 at the crank.

I do plan on doing a cam break in and basic tune on the engine dyno before installation.

I think your dreams are achievable
Have fun cruising around in it
BTW, do you have your captains license to be able pilot that yacht lawfully

I think it will work great, the only way to know is to just do it.

I ran down to .027 on a 318 with closed chamber heads milled .030 and flat top pistons with no valve reliefs and stock 5.9 magnum cam. It had lots of low end TQ, great MPG and never a sign of pinging towing a car out of LA on an open car trailer on those big passes. Oh and it was 87 octane. I think it was around 11.5 compression. With closed chamber aluminum heads, .030 clearance (set piston to wall clearance on the tight side to minimize piston rock) and a slightly bigger than stock cam I bet you would be fine running 11 to 1 in a 440. The stock beer barrel intake I was running absolutely bakes the air entering the cylinder head.

I think it looks like a nice setup for what you want to do.

I would personally install it at 108 icl instead of 106.

Don't know how many times I have posted this, but, your engine sounds like a good combination. If you want some peace of mind before spending the time and money, buy a good engine program, and run your combination. I use performance trends, it will calculate a timing curve, predict detonation, for different octane fuels, cranking compression, idle vacuum, etc. etc. I have built a lot of engines using this program, and they are always close on a real dyno. And the manual that comes with it will teach you tons about the science of how an engine works.

10.2 CR and aluminum heads with tight quench should live a nice long happy life on pump gas especially if you add engine management to the equation.

Kevin

I wasn't happy with the deck so I dropped the block off at a well known shop. The man running the place has been at it nearly as long as I've been alive. He is a man of few words but made more than one comment about needing to drop the compression or add more cam. It made me a bit paranoid.

Stay with the CH4B.

10.2 with an iron head and a cam that makes cylinder pressure might be iffy on 91 but with an aluminum head it should behave like it has 9.2.

Kevin

Slightly off topic.
New York cab drivers must be the best in the world, they do millions of miles.
No, they just make the same mistakes millions of times.