Jeep Strokers

HI folks

I typically hang out on Jeepforum... so thank you in advance for your advices and thoughts.... here's where I am at!

Two weeks ago, I had a fully functioning 258 with stock Carter BBD carb and associated vacuum hoses/plumbing. It ran very well. It never let me down up or down hill!

However in the true tradition of 'if it ain't broke fix it till it is', I have removed the engine, purchased a Compcams 239 cam, own a 4.0 '93 head, MPFI ECM/wiring, T5, 4:56 gears, new lifters AND 12 very shiny P5249464 valve springs.

I need to understand the following;

1. DO I need the Mopar P4452032 retainers or is there an (read lower cost) alternative?
2. Regardless of 1st question, do I need to use new retainer keepers?
3. For break in, is it really necessary to remove the inner spring from the valve springs and if so, does one run it as per spec for a few revs / minute and then take the valve cover off, then the springs, then repeat? Is there a way around it?
4. Do I use the same push rods (4.2 258)? Or should I get some 4.0 rods or something else?

I'm excited to build something I've never done before... the engine stand was a day's work!!!!

Looking forward to your thoughts, thank you.

Also... I have the 703 injectors from the Neon....., Hesco CPS harmonic balancer.....

1: Don't know of any, but there may be something that fits
2: I believe the stock ones fit
3: There is no inner spring, follow the cam manufacture's directions for break in
4: Check preload then determine which rods to use. I'm not that familiar with the 4.2L to 4.0L head swap.

So the springs I plan on using are the Mopar that have a damper spring in the middle. Instructions are to break in without, then add them in.

Can I use the 239 cam from Comp cam with fuel injection despite it suggesting I use a different one that is more useable for EFI??

I will be using the 4.2 block, 4.0 HO head, 4.2 push rods.....

Don't remove the damper spring. That is what it is. It's just a damper. It stops (or dampens) valve spring harmoincs or vibrations. You only have to remove the inner spring on a dual spring application, for cam break in. The mopar performance springs are a single spring with a damper, not a dual spring.

As for valve spring retainers, I read somewhere that the dodge 2.2 retainer is the same size as the mopar performance retainer. I cannot confirm that. If you can find a 2.2 in a junk yard check the size. It might be a cheaper alternative.

I did look at those - they are the same as the magnum retainers... i think that the inner damper spring inner dimension is smaller than the outer dimension of the lowest step.

Thanks for your help with the inner spring vs damper issue... didnt want to take the valve cover off again if i could avoid it!