Roller cam push rods

[jimynick]

Hopefully, some of you folks have been there and done that, but I'm wanting to get going on the stroker 408 for my Challenger, and a thought came to mind. It's a Magnum block, but I've got LA heads for it and was going to use the oem roller lifters on my Lunati cam. Don't the oem lifters oil through and up to the pushrods? Will the stock pushrods suffice! Will I have a length issue even though I also have adjustable roller rockers? Any guidance will be appreciated, so thanks! 
PS- will the LA head gaskets work and just cover the oil feed holes in the LA heads/magnum block interface, ok?

[Filthy Filbert]

Depending on the year of your block; determines your answer. 

Early years or 'cross over' years the blocks were drilled for rocker shaft oiling.

Once they went to magnum style heads with pedestal mounted rockers, they stopped drilling these oil passages and started using hollow pushrods. 

If your block is not drilled to the oil galley, then no your stock pushrods will not work.

[340challconvert]

I am going through the same assessment process
I picked up an ATK stroker 408 short block which is currently in storage.
I liked the ATK block because it was internally balanced and I would not need to deal with a different balancer and or torque converter.
It is a Magnum block; path of least resistance would be to get Magnum aluminum heads and convert to roller rockers and cam.
I also wanted to use an hydraulic cam with the provision for a mechanical fuel pump where the newer Magnum blocks use an electric fuel pump.

I was trying to avoid the expense of purchasing the Magnum parts, but the short block will allow me to choose heads and valve train that meet my needs and oiling would have to be through the push rods. Just expensive to do so.
In retrospect, I would have purchased a long block stroker which would have saved money and time,
A 408 stroker should be a blast to drive!
Good luck with what you decide; keep us posted on the route you take 

[340challconvert]

One purchaser of the ATK block went this route with parts;
ATK High Performance Engines SP61 - ATK High Performance Chrysler 408 A Stroker Short Blocks
I'm in the process of assembling this.
I'm using Edelbrock RPM alum. heads with 58cc chambers.
I'm also going to use Lunati Voodoo cam: 20200712 (hyd. roller)
[Duration @ .050 (Int/Exh): 231/239 ;Gross Valve Lift (Int/Exh): .535/.550]
I'm also have a Cometic head gasket that is only .027 thickness. Although the brochure recommends .048 thick one from Fel-pro. Can I still use the Cosmetic's?
I know it'll bump up the compression a bit, but it'll still be under 11:1 which is fine.

[Filthy Filbert]

You should be fine using the cometics.   They're a high quality gasket.  Do you have the quench area of around .040 between piston and chamber?  this creates swirl and helps relieve the tendency to detonate.   On a stock stroke 360, this is easiest to achieve with a true flat top piston with valve reliefs; at zero deck, with the fel-pro gasket.   On the 408 though, compression may be way to high with a full flat top, and you may need to run a dished piston.  Just make sure you still have .040-ish between the flat part of the chamber and the piston top.

[jimynick]

"no your stock pushrods will not work."  When I said "stock pushrods" I was referring to the magnum ones and not the LA ones. I have both as I got a complete donor engine. I haven't measured them, but wondered with the Lunati roller and stock oem roller lifters, if the accompanying stock roller push rods would work? 

[Chryco Psycho]

Short answer is No
Pushrod oiling will feed the magnum type rockers ok but unless the block is drilled to oil the LA rocker shafts there is no way to properly oil the rockers/ shafts .
You can use Magnum heads & rockers on an LA block & use pushrod oiling but nt the other way around , the rockers shafts will remain dry & the LA rockers do not feed oil properly from the pushrods .