what will i have to do to make this work? i have an LT4 hotcam im thinking of putting in a 400. can i reuse my lifters and pushrods?

 

lifters are out, not entirly sure on the pushrods.

To convert to roller you need lifters for that specific purpose. They have a link bar between them to keep them from rotating in their bore.

 

retro-lifters will need to be used. and i think you need roller cam pushrods too, which are a bit shorter than the stock non-roller ones.

here ya go:
Crane Hydraulic Roller Lifters: CRN-11532-16 - summitracing.com

that price makes a hyrdualic flat tappet cam look a bit more appealing, doesn't it...

 

You'll need a retrofit roller cam, a set of retrofit roller lifters, and shorter pushrods.

 

Why would you use that weenie little stock GM cam in a nice motor like a 400?

You'll HAVE TO use "retrofit" (the original design) roller lifters. You'll HAVE TO use the late-model timing set, to fit the small nose and bolt pattern on the cam. You'll HAVE TO make a spacer to go behind the cam gear, equal in thickness to the factory cam retainer. You'll HAVE TO turn a nylon cam button down to where it's small enough to fit in the center of the cam bolts.

Yes you can buy the "instructions" on eBay for putting factory roller lifters in a pre-modification block. I have no clue whether it will work or not; but I will say, the hardwre to hold the spider down bolts RIGHT DIRECTLY INTO the main oil gallery that feeds the cam, main, and rod bearings, and they will be serving icewater in Hell before I'll drill into that spot of my block. Others may feel differently.

Or, get a cam that's actually suitable for a 400 in the first place instead of that little stock thing, and just use the regular roller hardware that all the rest of us had been using for decades before the factory bastardized the blocks, and it will all drop right in and work perfect, just like it always has.

The push rods might work, if they're the right length. Only way to know, as always, is to use a push rod checker after the heads are on.

 

Are these steps bypassed by using a "retrofit" roller cam, as opposed to a "normal" roller cam? Or do you need to use them any time you put a roller cam in a non roller block?

this would be all "retrofit" parts? retro cam, retro lifters, and it all just "fits" ?

 

Right, all that first group of stuff is what you'd have to do to graunch the combo of parts together.

One of the "normal" roller parts is a cam button. You can get a roller one, or a nylon one, or a timing cover with it built in. I'm not sure whether the built-in will work with a factory roller timing sest, because the center is so small. But I know you can cut a nylon one down far enough to fit.

That cam is SMALL. It's smaller than its specs might make it look, because it's compromised to run with the crappy GM springs and not destroy them on startup, and with a near-stock FI computer.

Now if the guy wants to put TPI on his 400, then it doesn't matter; because the TPI will protect the 400 from ever being able to do its job..... MOVE AIR. With that extreme of a handicap, the cam fades into oblivion as a limiting factor to performance.

Yup. Been fitting that way for 30 years that I've been doing it, and 10 or more before that, too.

 

Hmmm.... that was strange.... it double-posted that.

 

who said anything about a stock cam? i was actually thinking of an LT4 hotcam that i got for my 350, but after looking at my block i dont know that i want to mess with trying to rebuild that motor and was just runnin over the idea of the 400. so IF i do the 400, its gonna have a flat tappet probably

 

You did. That's a REALLY TEENY TINY LITTLE cam for a 400. It's so small that in a 350, it works with the stock computer programming. That's just totally NOT a performance setup in a 400.

 

I see Sealed Power sells a more affordable roller lifter. Still expensive though.

eBay Motors: RETRO-FIT HYDRAULIC ROLLER LIFTERS - SBC CHEVY (item 200002062778 end time Jul-26-06 21:06:45 PDT)