I want to install the hot cam (gm part# 24502586) this weekend. I bought the unit from Bill Heard Chevrolet in Sugarland Texas for about $250. My 96 LT4 vert has 69K mi. and is stock except for Corsa catback. It dynos at 304/301 now. I'm hoping to pickup 25-30 ponies and create potential for another weekend project involving heads.
This is my plan simplified:
1. remove old cam with engine in car per Jim Mason's write up.
2. lube and install new cam observing known caveats.
3. re-use old valve train components including springs and push rods.
4. re-use timing chain.
fyi ... I planned to replace the springs b/c I read on the forum they were pretty cheap. The Chevy dealer wanted $180 + for 16 stock replacement springs.
I am unable to assemble from all the searches a parts list for the cam swap. I thought the dealer would help with this but it would not. You supply part number, they go "back there" and get it for you.
This project begins at 10:00 PM tonight. I am hoping to turn the key and grin by noon Sunday. The scary part is I have never worked on a chevy before. I tried to solicit paid help in both of the c4 wanted channels with no luck.
See http://forums.corvetteforum.com/zerothread?id=658521
Is it necessary to degee a cam? If so, can someone explain what it is. I thought I would just line up the dots like I did on my old T/A's.
Finally, HEEEEEEELLLLLLLLLLLLP!

 

I've installed 2 hot cams in my car by simply lining up the dots as you say. Is this the best way, probably not. However if you don't have everything that you need to properly degree the cam it will probably work unless somebody truly screwed up your grind.

 

Thanks Nathan,
Did you do the job with the engine in or out?

 

You can buy new LT4 springs, locks, and retainers for around $50.

Jim Mason's Hot Cammed LT4 is putting out 342 rwhp.

Don't use cam lube with roller lifters.

I didn't degree my camshaft, just installed it straight up.

Good Luck, you have a long weekend of wrench turning ahead.

 

engine in, but beware you will have to tilt it back or you won't be able to get the cam out, it hits the front crossmember. To tilt it back you've got to remove the torque arm :U

Last time I did this it took about 3 days. Good luck on having it run by Sunday, it's not impossible but you'll be dead. It took me 24 hours start to finish to swap the springs and do plugs and wires on my friend's car. Granted that included sleeping, and regular meals. Thing is that I've torn into the LT1 vettes a lot and I don't think I could do it that fast. Good luck!

 

Thanks STL94LT1, I didn't know about the no lube thingy. Seems I have a lot more reading to do on this subject. I recon just 5w30 rub down will do huh.

 

I didn't unbolt the c-channel. I just undid the motor mount bolts and lifted the front of the motor about 1". The cam slid out with the rad and cond out of the way.

 

http://www.hashmarks.com/techtips/hot_cam.htm

he seems pretty complete, also lots of pictures...

 

Glad people are finding it of use :)

FWIW, there's no need to unbolt the C beam between the transmission and differential. Like Rich said, just loosen the nuts (one/side) that secure the motor mounts to the frame bracing. Use a floor jack and a block of wood (to spread the load) under the oil pan or tranny to "lift" the engine. You need about an inch.

As for parts....

Here are the major ones...

Intake Manifold gaskets
Waterpump gaskets
Timing Chain Cover Gasket and the following seals in the timing cover:
Waterpump driveshaft seal (not mandatory, but "while you're in there")
Optispark seal (not mandatory, but "while you're in there")
Cranshaft seal (not mandatory, but "while you're in there")
Oil pan gasket
Valve cover gaskets (not necessary unless yours show sign of age)
Nice time for a new serpentine belt
Throttlebody to intake gasket (if showing signs of age, torn, etc)
Coolant refill (distilled water and Dexcool or equivalent)
Fresh oil and oil filter
Good time for fresh plugs and plug wires
Inspect and replace injector o-rings if needed, otherwise clean and lube them with a light coat of oil before reinstalling.

No need to discharge the a/c in order to remove the condensor. It's tight, but you can move the condensor enough the cam will come out with it hooked up.

The car WILL lope at idle with the stock 700rpm idle speed. Personal preference will determine if it's acceptable to you. Tuning will address this if desired.

LT4 valve springs are available from Chris at Superior Chevrolet for about $30. No need to replace the locks and retainers.

It took me right at 18 hours to do mine spread over a week. 4-5 hours of that time was spent cleaning things up, taking pictures, jotting down notes for my write-up, etc.

Hope this helps.

 

Thanks Jim, that is what I call going the extra mile. This is the joy of belonging to this forum. This thread is a jewel that should be mined for everyone looking to DIY instructions on the hot cam in an LT4. I will post progress. I also plan on taking a few photos along to the way. I am not sure what is up with the LT4 spring price my dealership quoted me. I will try another in the am.
[IMG][/IMG] :party: [IMG][/IMG]

 

My swap took about 4 days, A few things to consider....
Keep the motor in the car, all you have to do it loosen the motor mounts and jack the motor up alittle to get the cam out...also keep and eye on your power steering lines when your taking and putting on the balancer, its very easy to get carless or not pay attention and before you know it your wait for the dealler to order you a new line.
I just lined up the dots for degreeing my cam its works just fine, with my whole car stock (down to the air filter) I put down 311RW with the cam. I'm sure than my exhuast is really holding me back, I wouldn't expect 30hp without some sort of headers.
Also when your putting the front cover back on the motor make sure you RTV the bottem really well, and it helps to loosen the oil pan, drop it down alittle then put the cover on and then tighted up the oil pan. It ensures a really good seal and you can be sure you gasket is seating correctly.

One more thing I'm sure you already know....keep your bolts labeled, your going to have alot laying around and it would suck to have to guess and check your way back together. Good luck and let me know how it goes. :cheers: :thumbs:

 

Thanks MongooseLT4,
I'm about one hour away from starting disassembly. I'll just take my time and remove what I can and organize and label things carefully. I realize I need three important tools now.
1. Hub Puller Tool
2. Valve Spring Tool
3. Torque wrench
If any forum members have suggestions or recommendations about tools or tool brands please chime in. I will be at Sears by 10:00 am otherwise to see what they have. Thanks.

 

GM PART # 12551483
CATEGORY: Engine Valve Spring
GM LIST: $8.97
OUR PRICE: $5.11
DESCRIPTION: This single valve spring is use on 1996 LT4 Production Corvettes and ZZ4 crate engines. Technical Notes: Single spring with 1.32" O.D. and 1.22" solid height. The pressure at installed height IS 101# @ 1.78" with 332# the average rate of pounds per inch. Use with retainer P/N 10168424.

They price out to $80 + tax --> not bad from online retailer. But, the dealers will want the higher number putting it around $160. If you get a chance please post the GM Part # you have for the LT4 valve spring.

 

You can get tools cheap at this place:

Harbor Freight USA
17490 HWY 290
HOUSTON, TX 77040
Phone: 832-467-9442 http://www.Harborfreight.com

1/2" CLICKER TORQUE WRENCH $19.99

FRONT HUB REMOVER/INSTALLER SET $24.99
or
46 PC. BOLT PULLER SET $8.99 (the one I used, but need additional bolts)

I didnt' see the spring tool.

It'll take longer than you think. Just getting the 7mm bolts out of the radiator cover took me 3 days the first time.

I assume you have at least a Haynes manual? about $15 at autozone equivalent.

 

LT4 Valve Spring Set (16) Part #12495494 $29.91
Call Chris May At Superior Chevrolet 800-728-8267

 

Thanks STL94LT1,
I will run this part number by my local GM parts dealers. I do have another question for the forum. What does it mean to install a spring a 101# @ 1.78"? How do you set the install height and how do you measure the spring pressure?

 

All I have to say is.. Thanks! TankerVette for the great Link!!! :thumbs: I also wanted to know step by step what had to be done to change a cam.

I can't believe I finally found something like this to help me figure out what to do with my L98 219 cam installation, I've been asking arround but never found something good like this.

Would I be guessing if I said that installing a 219 cam in a L98 would be a very similar experience has the Hot cam in an LT4?

If not, does any have all the steps listed a L98?


[Modified by TheStef, 9:50 AM 9/27/2003]


[Modified by TheStef, 10:25 AM 9/27/2003]

 

Sorry! also..

Thanks Jim! I didn't realize your the one who had did all the work until I finished reading.

I'll really like to know if any one knows if the steps are pretty much the same on a L98.

 

Jim has also installed a cam in a L98. I'm sure he will chime in soon with the differences/similarities.

 

This means it should take 101 pounds of force to compress the spring to a height of 1.78". This is set by shimming the spring(s). You'll need a spring-checker (a tool) to perform this task.
It's not absolutely necessary that this be done, just like it is not absolutely necessary that the cam be degreed. These two processes are like a quality-control verification that the parts you have meet the manufacturers specifications. But they ARE good ideas....! (especially the springs)

Good luck and, like someone already said, if this is the first time you've done this sort of work, allot about three times the man-hours you think it should take. Seriously.

Larry
code5coupe
:seeya


[Modified by rocco16, 6:27 PM 9/27/2003]