Lower intake swap / Vortec head & cam install on stock bottom end

[Tooky]

Heads are off

Heads are off

3 more hours and the driver's head is off! Whoop, whoop! Just look at that little motor, reeking of "LB4", non-balance shaft badness... :lol:

Spent a fair amount of that time trying to drain the driver's side of the block after pulling the first headbolt out and having coolant pump all over just like the passenger's side! You'd assume they are connected in the block but evidently not! The little 9/16" bolt that plugs the driver's side turned out to be just impossible to remove so I had to give up and let the coolant run off the deck, down the block. I'd love to hear how anyone gets that thing out without removing the oil filter adapter.

Here are the #1, #3, #5's:

The driver's head gasket looks good to me. So I am not sure why my overflow was bubbling last year and why it had this same color brown coolant, but I didn't do anything and it stopped on it's own. I was kind of hoping to find something more of a smoking gun.

Driver's cylinder head: (I bet that little star means it's a super secret L35 casting! Quick - somebody notify "Partyboy" :rotf: )

I'm up to #80 on my major parts removal list, I'll be typing it up and sharing it here when my project is complete! It should serve as a nice little guide to anyone trying to do the same job in the future.

 

[Mtn Z]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

This is a project I intend to tackle in the very near future. Thanks for posting up the pics!

 

[Tooky]

Heads back from machine shop

Heads back from machine shop

Today I received my OEM "L92" GM beehive valve springs, I believe they are the same as the LS2 valve springs, both are yellow. Cost: $50. Unfortunately the Comp 787-12 retainer (for non-LS1 heads [i.e. Vortecs] running LS1-style Beehive springs) doesn't fit inside the LS2 valve spring! But its really close, in fact 2 out of the 16 springs fit the retainers. So I'm going to do a little grinding to the valve spring to make them fit.

I picked up the vortecs from the machine shop. This was the first machine work I have ever had done, and it went pretty well, all things considered. Here is the bill:

Cut heads for larger valve springs: $30
Resurface/mill heads flat for RA50 finish: $50
Drill intake surface to old pattern, drill 4 old style 1/4"x20 holes for factory dipstick/wire looms: $130
Flow test one intake, one exhaust port: $40
Total: $250

The prices seemed slightly high compared to what I have read others have paid here ($50-$75 for vortec head drilling), but I couldn't find any other shops to do it cheaper in a reasonable time period and this shop seemed very helpful & knowledgeable.

The resurfacing is a classic example of Things That Can Go Wrong. I originally bought the heads off eBay as "NEW" but upon receiving them I noticed they had been mounted to a head gasket and the head bolts tightened, but clearly never ran. Well the numb-nuts who owned them must have hit the deck with a "Scuzz Buster" (as the machinist called it) because here's what it looked like, and the machinist said this is a big "no-no" and said it would require a resurface:

They took .004" off the heads which they said was the minimum amount possible to cleanup the deck. The machinist drilled/tapped the intake holes per my instructions for 3/8-16 but said afterwards they would have preferred a finer thread considering how thin 3 of the 6 bolts threads turned out:

Since the Vortecs are not "made" to have the old pattern drilled; it's very thin here and you only get 3-4 threads when you're done. Compare to the Vortec factory intake holes which are at least 3/4" thick.


Here are the dipstick/wireloom holes done: (will require thread sealer since they go into coolant)

And the valve spring machining:

What's interesting is I instructed them to cut the valve guides for .550" lift clearance, the machinist assembled one cylinder with my factory Vortec valves, and my beehive springs/retainers, and he measured .590" clearance on the intake and .610" on the exhaust! I told them I was shocked since ALL the literature on the net says the Vortecs can only handle ".450" lift", so he gets the machinist that actually did the work and he says he's certain of his measurements and that it's plenty of clearance including the .050" safety margin (for my cam which will have .530" lift). So I got to save the $ it would cost to have the guides ground down and I can reuse the factory valve stem seals (which were obviously still new).

Now onto the bad news. The intake holes looked great at the shop, but I didn't think to lay the Felpro 1203 gasket over them while I was still there. I got home and it lines up like this!

That's with the gasket lined up to match the roof and floor of the intake ports... I'm not sure what they lined up the gasket with when they drilled the heads! At home, I tried taping the gasket to the intake, and having someone hold a spare (stock) intake manifold up with the 6 intake bolt holes lined up to the ones drilled in the heads, and here's what it looks like:

I guess that doesn't look too bad.... does it? I won't really know "for sure" until I get my modified vortec lower intake back to really test fit. I still can't imagine why they wouldn't have lined up the ports to the gasket when they marked the 6 intake holes for drilling...

The last thing is the flow numbers. After searching SyTy, I was expecting 220cfm intake and 155cfm exhaust. I wound up with 227cfm and 163cfm, slightly better than average. :lol: They are going to send me the full flow numbers tomorrow. These are totally stock 2004 (I believe) Vortec heads/valves. The old claims I've heard that stock vortecs flow 240, or even 250cfm are totally BOGUS... I've seen absolutely no evidence to substantiate that... ever. (unless you talk about V8 Vortecs which may be different than the V6 Vortecs)

I guess worst case scenario is the intake holes are drilled too low on the heads and I have to drill/slot the modified vortec lower intake manifold bolt holes to match. :roll: Lame, but not the end of the world.

 

[Black Knight]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

Josh defintely keep up the posting, I check your thread everyday because I love to read about how your doing.

We had to slot the holes in my intake so the bolts would line up with the heads. Maybe deck heights play such a big factor, but mine were off quite a bit too.

 

[Blazer69]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

damn josh really working at that thing huh? lol

 

[James Thomas]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

Tooky, better bolt up your manifolds to the heads and check the port alighnment. My Vortec ex. ports to manifold ports were way off! Check it out and see what yours look like http://www.syty.net/forums/showthread.php?t=44305

________
James

 

[nallj92]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

looks good, the 1203 holes dont sit dead center, but as long as your intake floors and roofs are aligned its all good. there isnt much to do to port match the head to intake also.

most places will take the gasket and center the ends and line up the bottom gasket with the bottom of the intake sealing surfaces in the front and back, this makes the holes not dead center on the 1203's

what did they flow out of curiosity?

the threads for the intake will be fine just have to watch it when tightening.

you planning a injector upgrade also? or just spray more alky?

later

 

[TYHOGG]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

Tooky, keep up the good work. Your thread has been extremely informative. I have debated doing to vortech swap myself since i have an extra set of heads (772) castings laying around. Its really nice to see the pictures and get a good visual representaion of what needs to be done to swap the heads. I appreciate all the work you have put into this.

1 question, which holes on the stock lower manifold do not line up? Is it all of them or just the 2 in the center (picture or the gasket off center of the holes)?

I plan on machining aluminium plates to conpensate for the raised runner on the vortechs (probly around 1/4"), and spacers for the front and rear and weld everything together.

Thanks for the help,
-Adam

 

[turbodig]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

Mark Larson strongly advised me to stay away from the poly mounts and his advice was to use nothing but stock GM mounts. I know you're local to him - do you know why he might have felt that way? I haven't talked to him in a while.

In the past, people didn't mount them correctly or shield them properly.

You *must* use the good-condition stock shield, + extra thermotec material to separate it from the manifold. You can't just slap it together (not like you would).

It's really hot down there. You've gotta get air to them and keep the manifold's heat away.

They do, and will work. There was a time where everybody tried them, without properly insulating. They got a bad name, and it stuck.

Rubber will die under excess heat, too, just not as fast.

I personally do not like solid mounts on any street-driven vehicle. Further, the excess mount height makes some things a pain in the hump.

 

[MikeRenz]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

You *must* use the good-condition stock shield, + extra thermotec material to separate it from the manifold. You can't just slap it together (not like you would).

or if you're patient, i'll have some stainless heat shields with thermotec soon (but after NATS) :tup:

 

[turbodig]

Re: Other Questions

Re: Other Questions

Anyone have any suggestions for other things I should do while I have it this far apart? I thought of replacing the motor mounts with fresh GM ones just for the hell of it, but it will be a challenge to find someone who can borrow me a cherry picker, and I've never pulled a motor before either so I'm sure that'll add an extra 12 hours. :lol:

Someone suggested replacing the rod bolts since I plan on spinning the motor higher than stock, can you even do that while the motor is installed? The rod bolts I've looked at always seemed like they were press-fit into the rod.

I wouldn't worry about it to 5200 RPM. Past that, engine build overall becomes a question.

You don't need a cherry-picker. Get a block and tackle, or a come-along. Put a loop of chain up near the garage roof peak. Hitch on there, and lift. You don't need to move it much.

You're not far from pulling the motor....

If you can borrow an inside mic, check your bores for out-of-round.

Your engine has been pinging, as you suspected. #2 is a regular culprit. #6 might be due to ignition, as that's the wire that takes the most abuse. As long as you still have your ring lands intact, you're good to go.

You have to ask yourself, though, if it has been pinging, what do the rod bearings look like?

You're soo bloody close to a motor pull now, I'd yank it for the piece of mind.

 

[turbodig]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

or if you're patient, i'll have some stainless heat shields with thermotec soon (but after NATS) :tup:

Cool. Hopefully literally.

 

[turbodig]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

I plan on machining aluminium plates to conpensate for the raised runner on the vortechs (probly around 1/4"), and spacers for the front and rear and weld everything together.

Thanks for the help,
-Adam

That was done a while ago... not many stuck with it.
It's a much cleaner, more effective mod to weld up the intake... you'll be happier.

 

[turbodig]

Re: Heads back from machine shop

Re: Heads back from machine shop

Today I received my OEM "L92" GM beehive valve springs, I believe they are the same as the LS2 valve springs, both are yellow. Cost: $50. Unfortunately the Comp 787-12 retainer (for non-LS1 heads [i.e. Vortecs] running LS1-style Beehive springs) doesn't fit inside the LS2 valve spring! But its really close, in fact 2 out of the 16 springs fit the retainers. So I'm going to do a little grinding to the valve spring to make them fit.

Yikes. I'd recommend a fine grit drum. You really don't want any stress risers in the spring, and you don't want to grind enough to cause them to heat.

The resurfacing is a classic example of Things That Can Go Wrong. I originally bought the heads off eBay as "NEW" but upon receiving them I noticed they had been mounted to a head gasket and the head bolts tightened, but clearly never ran. Well the numb-nuts who owned them must have hit the deck with a "Scuzz Buster" (as the machinist called it) because here's what it looked like, and the machinist said this is a big "no-no" and said it would require a resurface:

While he's right, flatter is gooder, I've seen hundreds of heads go on like that and are just fine. And with much higher cylinder pressures.

The shave was a good idea, just to insure level. Never know what you get with used stuff.

I guess that doesn't look too bad.... does it? I won't really know "for sure" until I get my modified vortec lower intake back to really test fit. I still can't imagine why they wouldn't have lined up the ports to the gasket when they marked the 6 intake holes for drilling...

Time. Machine shops make their $$$ on time.

Look at the roof matchup on the intake... that's the tough one.

The last thing is the flow numbers. After searching SyTy, I was expecting 220cfm intake and 155cfm exhaust. I wound up with 227cfm and 163cfm, slightly better than average. :lol: They are going to send me the full flow numbers tomorrow. These are totally stock 2004 (I believe) Vortec heads/valves. The old claims I've heard that stock vortecs flow 240, or even 250cfm are totally BOGUS... I've seen absolutely no evidence to substantiate that... ever. (unless you talk about V8 Vortecs which may be different than the V6 Vortecs)

Seats can make that much difference. Heck, flowbench differences can make that much difference. I would have had them all flowed, personally. Helpful to know which cyls are out of balance, and how much.

I guess worst case scenario is the intake holes are drilled too low on the heads and I have to drill/slot the modified vortec lower intake manifold bolt holes to match. :roll: Lame, but not the end of the world.

As long as it doesn't leak. If they're off by a lot, I'd make the machine shop fix it. You paid them to be good at it...

 

[MikeRenz]

Re: Heads back from machine shop

Re: Heads back from machine shop

You paid them to be good at it

live and die by that.

 

[E-Rue]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

iv probably had 20 different people ask me to drill and tap their vortecs for the intake manifold, and every time i refuse. because there are way to many things that can be modified or changed, that are specific to their motor, to assume that because it fits on a test motor here, that it will fit on their motor half way across the US. we always mark the heads by bolting them to the actual block being used in the build, after its been squared, with a spare set of headgaskets that are the same thickness as the ones being used in final assembly. (also a good time to make sure your ports line up perfectly) how else are you gonna ensure you have the same deck height or headgasket thickness, intake gasket.....ect. if its not too bad, id slot the intake and deal with it, because theres no good way to fix it once its drilled wrong. you can try again using a slightly larger intake bolt, but without taking the motor out of the truck, so that they can see what you see.......i would put it together and drive it. actually now that i think about it, in the picture you took, its not on the motor is it? nevermind anything i just said..... before guessing at how far off it is, and why its that far off, finish putting it together and find out how far off it is. otherwise your just guessing......... just like the machine shop did when they drilled them.

e

 

[Tooky]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

most places will take the gasket and center the ends and line up the bottom gasket with the bottom of the intake sealing surfaces in the front and back, this makes the holes not dead center on the 1203's

Yeah thats' what I'm betting they did. When I sit the bottom 2 "tabs" of the 1203 with the bottom of the head's intake surface, the all the holes line right up with the center of where they drilled :roll: (This also answers GreenTyGuy's question).

what did they flow out of curiosity?

Check my last post, with the photos of the heads. They flowed 227cfm intake, 163cfm exhaust.

the threads for the intake will be fine just have to watch it when tightening.

you planning a injector upgrade also? or just spray more alky?

I was planning on using the factory intake torque spec, I guess I'll have to see how it 'feels'.

I have been sitting on some 50# injectors for about 3 years now, I guess I'll have to install them but I wish they were 65#'s..

To turbodig, GreenTyGuy, and erue, thanks for your comments/advice! Monday will be a big day as I recieve my modified lower intake manifold and a large parts/tools order. I ordered the Edelbrock double roller timing chain 7801 which Summit says won't fit behind the stock cover but everyone here says it will, so I'm trusting you guys. I also decided on the basic ARP SBC 6 point head bolts 134-3601. I can't justify doubling the price for the "Pro Series" on this motor, when the factory GM bolts worked so well already. Also picked up some thread chasers for the block, a Comp digital caliper and dial indicator/magnetic anchor etc.

 

[Tooky]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

3 more hrs tonight and I got the head gaskets off, 80% of the deck scraping done, and the harmonic balancer pulled. Slow, but I take my time as I've never done any of this before.

I found this strange number on the passenger's deck:

The balancer only had one little spot drilled, about the size of half a pea. So hopefully that means this motor was a good balance to begin with.

The head gaskets came off good and look really good IMO:

I'll have to do some block cleaning and fix what I assume is a leaky turbo oil drain rubber hose under neath this mess:

 

[warmpancakes]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

Those numbers are from the rebuilder of the motor for warranty tracking

 

[Syclone#892]

Re: Lower intake swap / Vortec head & cam install on stock bottom end

Well to me those look like the #'s that gm puts on the block. Well at least the 4 blocks I have laying around that have those. 2 are balance shaft for the sogt and 2 non balance shaft for the sy and ty.
Looking good hopefully you won't run out of time to finish. Good luck.