Lower intake swap / Vortec head & cam install on stock bottom end
- Thread starter Tooky
- Start date
Tooky
Serious about performance
Next Major Update
Next Major Update
Wow, a lot has happened since my last update. I estimate I'm into this about 50-100 hours at this point. It's definitely got to be about the biggest job you could do on one of these trucks short of rebuilding the motor and transmission at the same time. :lol: I take it slow and steady, doing my homework for any steps I'm uncertain of before I proceed.
PITA Front Oil Pan Seal
Sunday night I got to the point of real frustration and losing motivation. I found out the timing cover oil pan seal is actually a huge bitch that I wasn't aware of. In fact I found an awesome cam swap photo guide for 5.7L V8 TPI motors that admitted this is the worst part of the swap. My research suggests that to do it by the book, you have to drop the oil pan which (on a 4WD) requires unbolting the front differential, at least a 6 hour job, or pulling the motor. If you dropped the pan just an inch, it would be a huge nightmare trying to fish a big 1-piece oil pan gasket around the oil pump pickup. I found a good SyTy timing chain guide at SyTyArchives that has a "trick" where you order the Fel-pro TCS45121 SBC timing cover gasket kit, cut off the front of the stock oil pan gasket, and glue the Fel-pro "U" shaped piece on the timing cover, and reinstall without ever dropping the oil pan. I also found tricks where you cut the lip off the timing cover and use RTV and just reinstall it over the stock gasket which sounds like the most attractive option of all. Here's what I'm talking about:
You can see the gray stock oil pan gasket at the bottom of the oil pan, right under the crankshaft snout. I was lucky enough to not tear mine when I pried the timing cover off.
Here's that timing cover lip I was talking about. Guys cut off the end so it slides right back over the stock gasket.
New Parts/Tools
I got all my shipments of parts, gaskets, new tools, and my modified lower intake back. I'll post photos of the lower intake later. Sorry about the blurry text, poor JPEG compression.
I bought what an engine-building book recommends as the 3 most useful precision measuring tools:
1.) 0-6" calipers (I chose digital, dial calipers are another option). $50 from PowerhouseProducts.com, a division of Comp Cams.
2.) 0-1" dial indicator good to .001", with magnetic stand. $60 together
3.) 0-1" outside micrometer good to .0001", $20.
After playing with these tools and measuring some things, I don't know how I lived without them!! This job is a lot of work but I'm so glad to be doing it myself. After this project is done, I'll post up a full parts/tools/costs bill so you can see what it would cost to do the same project yourself.
I also bought 2 "double cut" carbide cutters which are recommended as the best burr for grinding cast iron (exhaust manifolds). $18 a piece at the local hardware store, but reputed to last a lot longer than the Standard Abrasives porting cartridge rolls. I started porting the exhaust manifold turbo outlet, WOW these babies cut like a dream with the Harbor Freight electric die grinder!
Playing with my new tools: (now I feel like a "real" engine builder :rotf: :lol: )
(continued next post...)
Next Major Update
Wow, a lot has happened since my last update. I estimate I'm into this about 50-100 hours at this point. It's definitely got to be about the biggest job you could do on one of these trucks short of rebuilding the motor and transmission at the same time. :lol: I take it slow and steady, doing my homework for any steps I'm uncertain of before I proceed.
PITA Front Oil Pan Seal
Sunday night I got to the point of real frustration and losing motivation. I found out the timing cover oil pan seal is actually a huge bitch that I wasn't aware of. In fact I found an awesome cam swap photo guide for 5.7L V8 TPI motors that admitted this is the worst part of the swap. My research suggests that to do it by the book, you have to drop the oil pan which (on a 4WD) requires unbolting the front differential, at least a 6 hour job, or pulling the motor. If you dropped the pan just an inch, it would be a huge nightmare trying to fish a big 1-piece oil pan gasket around the oil pump pickup. I found a good SyTy timing chain guide at SyTyArchives that has a "trick" where you order the Fel-pro TCS45121 SBC timing cover gasket kit, cut off the front of the stock oil pan gasket, and glue the Fel-pro "U" shaped piece on the timing cover, and reinstall without ever dropping the oil pan. I also found tricks where you cut the lip off the timing cover and use RTV and just reinstall it over the stock gasket which sounds like the most attractive option of all. Here's what I'm talking about:
You can see the gray stock oil pan gasket at the bottom of the oil pan, right under the crankshaft snout. I was lucky enough to not tear mine when I pried the timing cover off.
Here's that timing cover lip I was talking about. Guys cut off the end so it slides right back over the stock gasket.
New Parts/Tools
I got all my shipments of parts, gaskets, new tools, and my modified lower intake back. I'll post photos of the lower intake later. Sorry about the blurry text, poor JPEG compression.
I bought what an engine-building book recommends as the 3 most useful precision measuring tools:
1.) 0-6" calipers (I chose digital, dial calipers are another option). $50 from PowerhouseProducts.com, a division of Comp Cams.
2.) 0-1" dial indicator good to .001", with magnetic stand. $60 together
3.) 0-1" outside micrometer good to .0001", $20.
After playing with these tools and measuring some things, I don't know how I lived without them!! This job is a lot of work but I'm so glad to be doing it myself. After this project is done, I'll post up a full parts/tools/costs bill so you can see what it would cost to do the same project yourself.
I also bought 2 "double cut" carbide cutters which are recommended as the best burr for grinding cast iron (exhaust manifolds). $18 a piece at the local hardware store, but reputed to last a lot longer than the Standard Abrasives porting cartridge rolls. I started porting the exhaust manifold turbo outlet, WOW these babies cut like a dream with the Harbor Freight electric die grinder!
Playing with my new tools: (now I feel like a "real" engine builder :rotf: :lol: )
(continued next post...)
Last edited:
Tooky
Serious about performance
Re: Lower intake swap / Vortec head & cam install on stock bottom end
Lower Intake Test Fitment
I bolted the lower intake to the drilled Vortec heads with the 1203 gasket. It's not as bad as it looked, actually it looks really good. I won't REALLY know for sure until I get it mounted on the block and try to connect BOTH sides..
With the manifold/gaskets lined up like this...
The ports look like this...
Obviously the top doesnt match at all yet, but that's why I'm porting the manifold (see 1st page of this post).
The "GOLD MINE" Information - Swapping a cam without pulling the motor OR A/C
Boy this one almost stopped me dead in my tracks. I spent many hours searching and found practically nobody who had ever swapped a cam on an S10 with A/C and without pulling the motor. Jim (Leroy here on SyTy) says he did it about 10 years ago and I think that was the only person! I found something on Crane Cams website about 4.3L S10s: "In most cases, a cam change can be made without pulling the A/C condenser." Sure wish they had elaborated! :roll: Gee, thanks for nothing..
Here's my new cam, held up as reference to show the condensor's interference:
Since the cam bearings are a precise fit, you can't just "cock" the camshaft sideways and sneek it out. Or at least, I certainly wouldn't/didn't try. If you try to pull the stock cam out, you'll get to about halfway thru the distributor gear and the dowel pin of the cam will be in the condensor fins, this is assuming you removed the rubber condensor mounts and have the condensor flush against the core support.
So after banging my head against the wall, at 4AM this morning I came up with the solution. Pull the condensor IN and UP, instead of trying to pull it BACK!
And now, The Million Dollar Photo:
The above photo was taken just minutes AFTER I got the stock camshaft out!!! WaaaaaHoooo!! :lol: :woot:
I got the condensor ready, and then used 1 hand to hold it up and 1 hand to slide the cam out underneath the condensor. I had at least an extra inch of clearance, no problem!
My elation was short lived however, when I found out I had nicked all the cam bearings!!
:roll:
The first 3 cam bearings all look like this. I can feel a slight spot with my finger tip. Obviously, I tried to be as careful as possible but with no room for a handle and trying to do it myself I clearly wasn't careful enough. I did some more homework and it sounds like a handful of people with other cars have nicked their cam bearings this bad or worse and put it back together with their new cam and had no problems. So I'm thinking of just going with it and crossing my fingers. But open to any advice/opinions from those more knowledgeable than me! A friend suggested using some light scotchbrite cloth to lightly polish the high spots out.. I'd do it but I'm afraid of making the bearing worse than it is. Thoughts?
Now I'm officially half way done with this thing!
PS: I would certainly recommend pulling the motor to anyone who has the resources to do so! It would be a lot easier and probably less time after you factor in how easy it would be to do all the head bolts etc. and the timing cover/oil pan would be a cinch. I am not that fortunate however, so this post should be a nice guide for anyone else who can't pull their motor but still wants to do a cam swap.
Lower Intake Test Fitment
I bolted the lower intake to the drilled Vortec heads with the 1203 gasket. It's not as bad as it looked, actually it looks really good. I won't REALLY know for sure until I get it mounted on the block and try to connect BOTH sides..
With the manifold/gaskets lined up like this...
The ports look like this...
Obviously the top doesnt match at all yet, but that's why I'm porting the manifold (see 1st page of this post).
The "GOLD MINE" Information - Swapping a cam without pulling the motor OR A/C
Boy this one almost stopped me dead in my tracks. I spent many hours searching and found practically nobody who had ever swapped a cam on an S10 with A/C and without pulling the motor. Jim (Leroy here on SyTy) says he did it about 10 years ago and I think that was the only person! I found something on Crane Cams website about 4.3L S10s: "In most cases, a cam change can be made without pulling the A/C condenser." Sure wish they had elaborated! :roll: Gee, thanks for nothing..
Here's my new cam, held up as reference to show the condensor's interference:
Since the cam bearings are a precise fit, you can't just "cock" the camshaft sideways and sneek it out. Or at least, I certainly wouldn't/didn't try. If you try to pull the stock cam out, you'll get to about halfway thru the distributor gear and the dowel pin of the cam will be in the condensor fins, this is assuming you removed the rubber condensor mounts and have the condensor flush against the core support.
So after banging my head against the wall, at 4AM this morning I came up with the solution. Pull the condensor IN and UP, instead of trying to pull it BACK!
And now, The Million Dollar Photo:
The above photo was taken just minutes AFTER I got the stock camshaft out!!! WaaaaaHoooo!! :lol: :woot:
I got the condensor ready, and then used 1 hand to hold it up and 1 hand to slide the cam out underneath the condensor. I had at least an extra inch of clearance, no problem!
My elation was short lived however, when I found out I had nicked all the cam bearings!!
:roll:
The first 3 cam bearings all look like this. I can feel a slight spot with my finger tip. Obviously, I tried to be as careful as possible but with no room for a handle and trying to do it myself I clearly wasn't careful enough. I did some more homework and it sounds like a handful of people with other cars have nicked their cam bearings this bad or worse and put it back together with their new cam and had no problems. So I'm thinking of just going with it and crossing my fingers. But open to any advice/opinions from those more knowledgeable than me! A friend suggested using some light scotchbrite cloth to lightly polish the high spots out.. I'd do it but I'm afraid of making the bearing worse than it is. Thoughts?
Now I'm officially half way done with this thing!
PS: I would certainly recommend pulling the motor to anyone who has the resources to do so! It would be a lot easier and probably less time after you factor in how easy it would be to do all the head bolts etc. and the timing cover/oil pan would be a cinch. I am not that fortunate however, so this post should be a nice guide for anyone else who can't pull their motor but still wants to do a cam swap.
Tooky
Serious about performance
Flow Numbers
Flow Numbers
I got the flow numbers back from the machine shop. Here they are, ~2004 Vortec heads, 100% stock and brand new with stock valves.
SuperFlow 600 bench at 28" water with a 4.00" bore.
Flow Numbers
I got the flow numbers back from the machine shop. Here they are, ~2004 Vortec heads, 100% stock and brand new with stock valves.
SuperFlow 600 bench at 28" water with a 4.00" bore.
Code:
[FONT=Courier New]__________________________________________
FLOW PRO Compare Data Report
__________________________________________
No. Test No. Test Name
--- --------- -------------------- -
1 54 Chev V-6
2 55 Chev V-6
__________________________________________
CCFM
Lift No. 1 No. 2
-------- ------- -------
0.0500 31.3 24.7
0.1000 62.6 49.3
0.1500 97.0 77.5
0.2000 131.3 105.7
0.2500 159.0 122.2
0.3000 186.6 138.7
0.3500 202.5 147.1
0.4000 218.5 155.5
0.4500 227.3 159.3
0.5000 216.0 162.6
0.5500 219.0 163.9
0.6000 217.2 165.2 [/FONT]
Last edited:
TurboTony
Active member
Re: Lower intake swap / Vortec head & cam install on stock bottom end
Just run the Cam bearings the way it is. Remeber, the cam turns at 1/2 engine speed, I really wouldn't worry about a few nicks.
Its just about impossible to get a cam in or out of a motor without nicking one of the bearings.
Don't take this the wrong way, but I would guess that the bottom end will need a rebuild in the very near future anyway. If you really want to see the gains that the heads and cam give the extra RPM you will be using will kill the stock rods, pistons and bearings in short order.
Tony
Just run the Cam bearings the way it is. Remeber, the cam turns at 1/2 engine speed, I really wouldn't worry about a few nicks.
Its just about impossible to get a cam in or out of a motor without nicking one of the bearings.
Don't take this the wrong way, but I would guess that the bottom end will need a rebuild in the very near future anyway. If you really want to see the gains that the heads and cam give the extra RPM you will be using will kill the stock rods, pistons and bearings in short order.
Tony
supersports10
New member
Re: Lower intake swap / Vortec head & cam install on stock bottom end
i still say you should have brought it over put it on my LIFT, and had it done in a day.
that would have been sweet!!!!
i still say you should have brought it over put it on my LIFT, and had it done in a day.
that would have been sweet!!!!
Tooky
Serious about performance
Re: Lower intake swap / Vortec head & cam install on stock bottom end
I got my new cam installed tonight and when I went to install my Edelbrock #7801 double roller timing chain, it seems like I'm getting some interference. When I change back to the stock cam sprocket, it rotates smoothly. I put a dab of assembly lube on the block where I thought it was hitting, and put the Edelbrock sprocket on. It left a tell-tale mark on the sprocket.
I'm going to post this in the Engine Tech section for a seperate thread, but does anyone here know if it's safe and correct to grind the block with a die grinder? Obviously I'll have to make an "apron" or something to keep any shavings from going into the motor.
I bought this timing chain on a recommendation from Michael Hood that everyone uses these in SyTys... I searched and couldn't find anyone else who has this problem. Did I forget something when I reinstalled the cam? I put the cam in, the blue torx-bolted retainer plate, and then put the timing sprocket directly on that, seating the dowel pin. If there was something that fits between those two, I'd have enough clearance.
I got my new cam installed tonight and when I went to install my Edelbrock #7801 double roller timing chain, it seems like I'm getting some interference. When I change back to the stock cam sprocket, it rotates smoothly. I put a dab of assembly lube on the block where I thought it was hitting, and put the Edelbrock sprocket on. It left a tell-tale mark on the sprocket.
I'm going to post this in the Engine Tech section for a seperate thread, but does anyone here know if it's safe and correct to grind the block with a die grinder? Obviously I'll have to make an "apron" or something to keep any shavings from going into the motor.
I bought this timing chain on a recommendation from Michael Hood that everyone uses these in SyTys... I searched and couldn't find anyone else who has this problem. Did I forget something when I reinstalled the cam? I put the cam in, the blue torx-bolted retainer plate, and then put the timing sprocket directly on that, seating the dowel pin. If there was something that fits between those two, I'd have enough clearance.
Re: Lower intake swap / Vortec head & cam install on stock bottom end
I'm using this setup. although it only has like 250 miles on it....it never hit the block.
I wouldn't grind down the block. i would check to see if you cam is recessed a tad too far. Something is a smidge wrong, and i doubt its the timing gear.
I'm using this setup. although it only has like 250 miles on it....it never hit the block.
I wouldn't grind down the block. i would check to see if you cam is recessed a tad too far. Something is a smidge wrong, and i doubt its the timing gear.
sytyguy
Moderated User
Re: Lower intake swap / Vortec head & cam install on stock bottom end
Josh, I've sold a ton of these timing sets and have installed 4 myself in the last 2 years. No clearance issues. Either your's is an isolated casting problem on the cam gear or there is something else amiss. Verify that your stock cam gear doesn't hit.....if it does, obviously you've got some figuring out to do.
Heed Mike's suggestion and the ones on the other post. Make sure the cam face is clean and that the gear is seating flush.
Let us know what you find out.
Hood
Josh, I've sold a ton of these timing sets and have installed 4 myself in the last 2 years. No clearance issues. Either your's is an isolated casting problem on the cam gear or there is something else amiss. Verify that your stock cam gear doesn't hit.....if it does, obviously you've got some figuring out to do.
Heed Mike's suggestion and the ones on the other post. Make sure the cam face is clean and that the gear is seating flush.
Let us know what you find out.
Hood
Tooky
Serious about performance
Re: Lower intake swap / Vortec head & cam install on stock bottom end
See my post:
i.e. it doesn't hit. The 7801 timing gear is a narrower overall diameter than the stock gear by about 1cm (I'd have to measure). But I did some homework and found at least 8 instances on thirdgen.org where 87-93 roller block 5.7L TPI owners had to do the same clearancing on their blocks when installing double roller cams.
Do any of you guys have the "073" block like me? One of the posts I found on the thirdgen site said the later years had more beef added to the block. Also, check out this Carcraft article: http://www.carcraft.com/techarticles/116_0108_chevy_350_crate_engine/index2.html, In particular this photo:
sytyguy said:
See my post:
i.e. it doesn't hit. The 7801 timing gear is a narrower overall diameter than the stock gear by about 1cm (I'd have to measure). But I did some homework and found at least 8 instances on thirdgen.org where 87-93 roller block 5.7L TPI owners had to do the same clearancing on their blocks when installing double roller cams.
Do any of you guys have the "073" block like me? One of the posts I found on the thirdgen site said the later years had more beef added to the block. Also, check out this Carcraft article: http://www.carcraft.com/techarticles/116_0108_chevy_350_crate_engine/index2.html, In particular this photo:
Unless I'm forgetting a component, it's all set right. Maybe I'll throw a dial indicator on the end and check the cam endplay but it feels right. I'd guess .030-.060". It definitely sits flush and true when I turn the cam over with the sprocket (until it contacts the block). I'm planning on grinding the block tomorrow and seeing how it feels then. It does seem awfully strange that I'd be the only one to have this problem Michael, but come to think of it, nalij92 mentioned having to do the same thing on one of his SyTy blocks in my Engine Tech thread on this subject.
Tooky
Serious about performance
Another monster update - Porting
Another monster update - Porting
Whew! My life has been consumed by this truck lately. After long enough you start to feel like you're bonding with your truck, really "getting to know it" well. :rotf: I'm practically in love with this thing, because I'm thinking it will be so kick ass when done.
Porting
Huge update today, hope all these photos don't crash people's web browsers. I've been doing some porting. I started with the turbo outlet on the exhaust manifolds. The center divider isn't as thin as it looks. My exhaust pattern showed both ports shifted to the left, so I took the center and made it like a triangle with a straight wall on the left outlet, and an angle on the right outlet. Then I evened both ports to approx. the same size..
I spent a lot of time working the manifolds' crossover outlets. I figure all the exhaust for the 3 cylinders has to choke through here; so it stands to reason the gains would be the biggest for opening it up. I like this picturesque summer day picture: :lol:
You can see the untouched driver's manifold on the left, and the ported passenger's manifold on the right. Here's a closeup of the passenger's manifold outlet. I took a significant amount out of the inside turn because there was so much meat in the walls. I also brought the opening to it's limit while still allowing a 100% seal to the crossover pipe flange.
Here's the driver's looong manifold outlet ported as far as I could reach...:
and a closeup:
Another monster update - Porting
Whew! My life has been consumed by this truck lately. After long enough you start to feel like you're bonding with your truck, really "getting to know it" well. :rotf: I'm practically in love with this thing, because I'm thinking it will be so kick ass when done.
Porting
Huge update today, hope all these photos don't crash people's web browsers. I've been doing some porting. I started with the turbo outlet on the exhaust manifolds. The center divider isn't as thin as it looks. My exhaust pattern showed both ports shifted to the left, so I took the center and made it like a triangle with a straight wall on the left outlet, and an angle on the right outlet. Then I evened both ports to approx. the same size..
I spent a lot of time working the manifolds' crossover outlets. I figure all the exhaust for the 3 cylinders has to choke through here; so it stands to reason the gains would be the biggest for opening it up. I like this picturesque summer day picture: :lol:
You can see the untouched driver's manifold on the left, and the ported passenger's manifold on the right. Here's a closeup of the passenger's manifold outlet. I took a significant amount out of the inside turn because there was so much meat in the walls. I also brought the opening to it's limit while still allowing a 100% seal to the crossover pipe flange.
Here's the driver's looong manifold outlet ported as far as I could reach...:
and a closeup:
Last edited:
Tooky
Serious about performance
Porting Pt 2
Porting Pt 2
Next is the PTE wastegate. Out of all the porting, this is the one I think will really deliver a real-world change.
^^ If I rolled a golf ball down this, would anyone else be reminded of Indiana Jones and the Temple of DOOM? :lol:
This should be pretty easy and I'm sure it will result in a dramatic increase in available flow through the wastegate port, judging by the size of that huge exhaust ring overlap mark..
Painting
I refinished some parts while I had this all apart. When I'm done, it should look better under the hood than it ever did since I bought it on April 7th, 2001 with 25,650 miles.
Stock head photos
Finally, I disassembled one cylinder of my stock LB4 heads. What I found was astonishing!!
Our stock heads have a ridiculous swirl casting in the intake ports! No wonder they reputedly flow ~165cfm. :roll: I can't believe I've never seen a photo posted of this since I've been a member of Syty.net, or at least I can't remember one. I tried getting an intake port photo but it's tough - just connect it visually from the intake port photo to the combustion chamber one.
You can see the air flows down like a hallway and then takes an abrupt "spiral staircase" up to the intake valve! It looks like a gimmick - I dont think anybody has produced anything like this on a cylinder head anytime recently. The Vortec heads in comparison, look like a standard performance head.
Here are my stock exhaust and intake valves. I'm sure they have seen some real "hell fire"! Hey - so much for that myth about alcohol injection "steam cleaning your pistons and valves to a mirror finish" eh? :roll:
Anyone getting sick of all these updates yet?
Porting Pt 2
Next is the PTE wastegate. Out of all the porting, this is the one I think will really deliver a real-world change.
^^ If I rolled a golf ball down this, would anyone else be reminded of Indiana Jones and the Temple of DOOM? :lol:
This should be pretty easy and I'm sure it will result in a dramatic increase in available flow through the wastegate port, judging by the size of that huge exhaust ring overlap mark..
Painting
I refinished some parts while I had this all apart. When I'm done, it should look better under the hood than it ever did since I bought it on April 7th, 2001 with 25,650 miles.
Stock head photos
Finally, I disassembled one cylinder of my stock LB4 heads. What I found was astonishing!!
Our stock heads have a ridiculous swirl casting in the intake ports! No wonder they reputedly flow ~165cfm. :roll: I can't believe I've never seen a photo posted of this since I've been a member of Syty.net, or at least I can't remember one. I tried getting an intake port photo but it's tough - just connect it visually from the intake port photo to the combustion chamber one.
You can see the air flows down like a hallway and then takes an abrupt "spiral staircase" up to the intake valve! It looks like a gimmick - I dont think anybody has produced anything like this on a cylinder head anytime recently. The Vortec heads in comparison, look like a standard performance head.
Here are my stock exhaust and intake valves. I'm sure they have seen some real "hell fire"! Hey - so much for that myth about alcohol injection "steam cleaning your pistons and valves to a mirror finish" eh? :roll:
Anyone getting sick of all these updates yet?
Last edited:
Black Knight
I Glow Therefore I am
Re: Porting Pt 2
Re: Porting Pt 2
Nope :tup:
Re: Porting Pt 2
Tooky said:Anyone getting sick of all these updates yet?
Nope :tup:
supersports10
New member
Re: Lower intake swap / Vortec head & cam install on stock bottom end
nope X2 keep it coming.... i love tooky posts!!! very detailed and informative!
tooky said:Anyone getting sick of all these updates yet?
nope X2 keep it coming.... i love tooky posts!!! very detailed and informative!
TurboTony
Active member
Re: Lower intake swap / Vortec head & cam install on stock bottom end
Don't open up the hole for the flapper very much. You'll find that if that hole gets too big the extra area will allow the pressure to overcome the w/g actuator and blow it open.
Makes for funky boost control, BTDT. Just leave the over all size of the hole alone and concentrate on blending it into the housing nicely.
Tony
Don't open up the hole for the flapper very much. You'll find that if that hole gets too big the extra area will allow the pressure to overcome the w/g actuator and blow it open.
Makes for funky boost control, BTDT. Just leave the over all size of the hole alone and concentrate on blending it into the housing nicely.
Tony
Tooky
Serious about performance
Re: Lower intake swap / Vortec head & cam install on stock bottom end
Today I finally got to mock up the lower intake manifold to the Vortec heads to see how the intake bolt pattern drilling really turned out. I threw down the .040" Cometic head gaskets I had on hand since they would make for easy mockup. Check out the intake bolt hole alignment!!:
I hand-snugged some ARP head bolts, taped the 1203 intake gaskets to the intake surfaces, and finally laid the modified lower intake manifold in it's new home to try the fitment. AND............ Lady Luck smiled upon me for a change!! The fitment of the intake is fabulous! :dizzy: :crazyeye: :thumbsup: Every bolt hole looks lined up pretty damn good with the intake! Every intake bolt threaded in with the greatest of ease by fingertip, and not one of them contacted the manifold whatsoever! After I surveyed it carefully, I almost have to come to the conclusion that I didn't give the machine shop nearly enough credit. I now suspect when they told me they found an old LB4 head to match up the 4 little oil dipstick accessory holes, that they may have also used it to determine precisely the original intake pattern. Maybe they drilled my holes "off center" from the 1203 gasket on purpose, because boy does it line up good. The only thing that could be a variable is I haven't added RTV to the china wall nor have I torqued the head gaskets, but so far, so good.
Here's the intake port floor alignment. I'm thinking of just spraying layout dye down the intake, wouldn't that mark the head where I need to port?
I also took the opportunity to mock up some parts on the engine:
The lower intake is going to be receiving paint. I was going to do the "cast aluminum" color of the thermostat neck pictured, but now I'm leaning towards the darker gray of the two big aluminum accessory brackets. What do you guys think? I want it to look like GM might have produced it this way factory, nothing bright or outrageous.
Today I finally got to mock up the lower intake manifold to the Vortec heads to see how the intake bolt pattern drilling really turned out. I threw down the .040" Cometic head gaskets I had on hand since they would make for easy mockup. Check out the intake bolt hole alignment!!:
I hand-snugged some ARP head bolts, taped the 1203 intake gaskets to the intake surfaces, and finally laid the modified lower intake manifold in it's new home to try the fitment. AND............ Lady Luck smiled upon me for a change!! The fitment of the intake is fabulous! :dizzy: :crazyeye: :thumbsup: Every bolt hole looks lined up pretty damn good with the intake! Every intake bolt threaded in with the greatest of ease by fingertip, and not one of them contacted the manifold whatsoever! After I surveyed it carefully, I almost have to come to the conclusion that I didn't give the machine shop nearly enough credit. I now suspect when they told me they found an old LB4 head to match up the 4 little oil dipstick accessory holes, that they may have also used it to determine precisely the original intake pattern. Maybe they drilled my holes "off center" from the 1203 gasket on purpose, because boy does it line up good. The only thing that could be a variable is I haven't added RTV to the china wall nor have I torqued the head gaskets, but so far, so good.
Here's the intake port floor alignment. I'm thinking of just spraying layout dye down the intake, wouldn't that mark the head where I need to port?
I also took the opportunity to mock up some parts on the engine:
The lower intake is going to be receiving paint. I was going to do the "cast aluminum" color of the thermostat neck pictured, but now I'm leaning towards the darker gray of the two big aluminum accessory brackets. What do you guys think? I want it to look like GM might have produced it this way factory, nothing bright or outrageous.
Black Knight
I Glow Therefore I am
Re: Lower intake swap / Vortec head & cam install on stock bottom end
I left all mine raw aluminum, but I like that look. It should look good either way.
I should also say that I had the upper plenum bead blasted so it is raw aluminum and would match the lower and freshly cleaned up T/B.
I left all mine raw aluminum, but I like that look. It should look good either way.
I should also say that I had the upper plenum bead blasted so it is raw aluminum and would match the lower and freshly cleaned up T/B.
James Thomas
"NO CLASS"
Re: Lower intake swap / Vortec head & cam install on stock bottom end
The lower intake is going to be receiving paint. I was going to do the "cast aluminum" color of the thermostat neck pictured said: