Heads etc. What do I have?

[E Satterfield]

Hello. I’m new to Mopars. We ordered a new 408 Blueprint for my wife’s Duster due to not having a local reputable machine shop so I decided to tear down the engine that was in it to basically see if there was anything that I could possibly sell to recover some of the funds for the new engine. It’s a 75 360 block
The heads are 340 X casting but it appears that someone has milled off the rocker pedestals and added these aluminum items for the roller rockers? One of the pedestals has been welded and one was observed broken in half during tear down. Is this a factory modification or done later by someone?
It also has deep dished pistons that look like the could be for a possible boosted application? Seem really dished even for a stock type 8-8.5-1 rebuild?

It’s also running a Comp solid lifter with nearly .500 lift. With the low compression a stock converter 650 double pump Open plenum intake and 2.76 gears I believe I can see why it was such a slug. Thanks for any info.

 

[cudamark]

It might have been pretty cool setup in it's day, but, there are better options now when you want to go fast. I doubt many would be interested in that setup seeing as how it broke. Who knows if the machine work was done properly. If the heads hadn't been milled, someone doing a 340 resto would want them (assuming they aren't cracked or surfaced too much), but, a racer would want to go aluminum these days. The short block would have a little value assuming it will bore within specs. What did they do with the bottom end? Stock cast crank? Billet? Stroker? Internal or external balance? etc....

 

[E Satterfield]

I’m new to the Mopar world. Just to clarify I am not trying to circumvent rules on selling things on this forum. After all the pictures I’ve looked at I’ve yet to see a set of heads done that way. So I supposed it was something someone had cobbled together. But also had hopes that they could be desirable. Nothing special about the short block other than 030 over. I’ve come over from Chevys and pistons with this type of dish are normally in a low compression mid 70s 350. I was really disappointed in how this car ran and was hoping someone would say that it’s this combination of crap hence the poor performance and not par for a Mopar small block especially when I have a new one on the way.

 

[cudamark]

It would depend on the original intent of the engine, and how the rest of the car was set up. Dished pistons are fine for a turbo motor, if done correctly. Also, what rear end gears and tires size used would have a big effect on how much performance you would get. What induction was used? What were the compression readings when it ran? What ignition and timing specs (both cam and ignition) were used? There's just too many variables to draw a conclusion at this point. Whoever might want your old parts would be building an engine their way, so, how it was set up in your engine has less importance to them. They'll mainly want to know current condition and what machine work has been done in the past.

 

[dano]

L2405 are Forged Pistons. Can you attach pictures of the intake and exhaust port, chambers and measure the valve size? It looks like someone worked those heads over. Rockers look to be Crane Gold, which is a good rocker. What were the head gaskets?

 

[MOPAROFFICIAL]

So if anyone's asking me... those look like old Big Block Rocker stands from say... a 413 or 'pick a pre 1964 big block of your choice'.

Are they moved back, are they small block or bb rockers.
Didnt look real close after seeing the stands..

Always funny to see that much work put into a head and then they leave all the flashing where the oil drains back where as if you removed it..it would make it back to the valley faster.
I started doing that on all the heads I work on, i just include it with the port job...and then stamp them with my initials & ###/### ..which are the flow numbers.

 

[dirty white boy]

id check the stroke on that motor!!

 

[33IMP]

Those look to be Crane small block rockers, with factory pre-1964 big block rocker stands.
I have used crane gold rockers with those stands on a maxwedge with a .650 lift roller. If the rocker geometry is right, they shouldn't break.
I did machine a set of billet 6061 stands to upgrade the cast stockers...... cause I could. Billet stands are available .

 

[Bobzilla]

I see lash caps on the valves too, but one is not in place.
Definitely check valve sizes and post more pictures. Someone put a little work into that engine. I am curious to see more.
Is that single plane intake off this engine as well?

 

[Garrett Ellison]

My builder will do the milled stand and custom aluminum rocker stands if he has free reign and someone isn't ready to go all the way to aluminum but wants to go racing with iron heads. They machine their own rocker blocks to make that modification with. The end result of that is to get installed spring height in the 1.80 inch area.