Preparation for heads, uim, camshaft and downpipe

[skinrock]

edit: I'm changing the LIM not UIM, I keep getting them mixed up.

I've pretty much got all the parts lined up, I'm thinking about doing a non-ported 3500 top end swap (stock uim). I know ported would be sweet, but I'm pretty happy with the numbers the 1393 ground cam puts out with stock 3500 parts. I also want to install a ZZP downpipe while I'm at it.

I know there's some extra parts like gaskets and bolts that I have to get, I'm pretty sure I have all those covered. My main concern is, what should I expect when I install all of this?

Is it going to be necessary to lift the engine out, or can all of this be done inside? The cam is the one that I fear the most, I'm pretty sure everything else can be done, but is it going to take some pretty serious work to do the cam?

I already have plans to do this with a family mechanic, and I have a week vacation during the first week of July, unless it can be done in a weekend. I just want to make sure I cover all my bases before I jump into this. It's my daily driver, and although I would have backup transportation, I'd rather not drive a V8 truck right now

[Superdave]

well, the top end stuff is the easy part, the cam isn't hard.. just more work.


Here is what i'd do..

With the engine in the car i'd drain the coolant and remove the plenum and lower intake and valve covers. Then loosen the rockers and turn them to the side. pull out the pushrods, remove the 4 bolts holding down the 2 lifter guides and then remove the lifters (put them in a container of oil).


I doubt you'll have room to get the cam out with the engine in the car, Some of the Jbody guys figured out that if you can lower the left side of the engine the cam will slide out through the wheel well. That's risky and will probably take more time than just pulling out the CV's, unhooking the wires/fluid lines and pulling the engine out the top.

Then just bolt on all the new stuff, follow all the torque specs and make sure to lube the hell out of the cam and pushrod ends before you put it all back together. I use Comp Cams white engine assembly lube. you'll probably need to measure for custom pushrods which is fairly easy. Ben may be able to shed some light if you'll need them or not with that grind. What are you planning on doing for valve springs?

Should be a good day's work if you don't slack at all.. pizza/beer breaks will turn it into a 2 day thing though.

[skinrock]

Trust me, this guy wouldn't take a break, lol. Once he starts, he'll want to get it done.

I think I asked Ben if I need the custom pushrods, I haven't gotten a reply yet.

As far as valve springs go, I'm not sure which part that is. Is that just the spring that holds the rocker back? Do I need to change them?

[whitelightnin04MC]

For your springs skinrock, you should atleast do the 3500 or LS1 springs. It would be a mistake to do all this work only to reuse your old, tired 3400 springs.

[skinrock]

Well I'm getting 3500 heads, so wouldn't they have 3500 springs?

[onefastV6]

Well I'm getting 3500 heads, so wouldn't they have 3500 springs?

Correct, the 3500 heads have the 3500 springs.

[whitelightnin04MC]

Well I'm getting 3500 heads, so wouldn't they have 3500 springs?

I wasn't sure where you were getting them from. Just because you get heads doesn't mean you get everything that comes with it. But, if you're getting them from here, then yeah, you'll have the 3500 springs.

[Superdave]

the 1393 cam is a .533 lift, you'd break the stock 3500 springs doing that..


you need atleast the LS6's, i'd go better and get a set of the 26915's from Comp cams.


search www.summitracing.com for part number 26915-12

[skinrock]

wow, I'm glad someone brought that up. are those ones from summit better than the LS6? also, how do you know if they will work or not, what measurement do you look at?

[skinrock]

Well, I don't think the cam is gonna be possible. It doesn't look like we really have the time or resources available to do that part.

Can the heads and LIM be done without lifting the engine out? That's really the key problem, it's gotta stay in the car, lol.

[whitelightnin04MC]

Your best bet would be to buy a cheap 3400 on ebay and build that motor up. Even if it is possible to swap heads with the motor in the car, it'd probably be MUCH easier to do with the motor out.

[SappySE107]

There is no reason to pull the motor just to swap the top end.

[ForcedFirebird]

There is no reason to pull the motor just to swap the top end.

I agree

[skinrock]

Ok, and what about the downpipe? I know where the cat end of the pipe is, I saw that when we did my dual exhaust, but I've never actually seen where the other end goes. Is that a hard to get area?

[whitelightnin04MC]

Ok, and what about the downpipe? I know where the cat end of the pipe is, I saw that when we did my dual exhaust, but I've never actually seen where the other end goes. Is that a hard to get area?

Nah man, where the downpipe bolts to the exh. manifold is really easy to get to. All you need are a couple of long extensions.