: Cam Replacement in Car



dalamak
02-20-09, 03:45 PM
Like title, can the cams be changed with the engine in the car?

Saw posting about people doing the HG with the engine in the car, but it being a bitch, Wondering if the cams can be done easier?

Submariner409
02-20-09, 04:35 PM
Unfortunately changing the cams (but, why???) involves removing the ignition system(s) and cam covers as well as the water pump drive. The job CAN be done with the engine in the car, but it requires so much equipment removal and endless engine jockeying, plus....retiming everything is an unholy bitch, that the whole task is better done on the ground (engine out the bottom).

Hank-Z
02-22-09, 06:42 PM
I have changed out cams , with the motor in the car. Not bad at all to do . Tha hardest part was puting the valve cover back on. Most of the time its been the front Int cam with the water pump drive brocken off, because the person thought that they could just slide it off and end up breaking the end of the cam off instead. Which cam or cams did you need to change ?

bigtone
02-22-09, 07:02 PM
As I had stated in my post about replacing my headgaskets with the engine in the car, timing the engine is relatively simple. I would place the engine at tdc for #1 cylinder, and lock it there. Tie wrap the chain to the cam gear. After you remove the cam gear, keep the chains tight with a bungee cord. Place the new cam in the same general orientation as the old one, tweak with a wrench if necessary, and reinstall the gear. If it is the rear cam, use a come-along to pull the engine forward, and you will have more clearance to r & r the valve cover.

Raze
02-25-09, 12:52 PM
I have changed out cams , with the motor in the car. Not bad at all to do . Tha hardest part was puting the valve cover back on. Most of the time its been the front Int cam with the water pump drive brocken off, because the person thought that they could just slide it off and end up breaking the end of the cam off instead. Which cam or cams did you need to change ?

I am confused, how the hell did someone 'break off the end of a cam' with a plastic valve cover?

You can do it, but you'd better mark your cams, timing chains, crank, everything to keep timing.

Just as a question, why are you replacing just the cams?

Submariner409
02-25-09, 03:18 PM
..................you, me, and a big crow bar couldn't break the end off an intake cam. Maybe screw up the seal surface or internal threads royally by trying to incorrectly pull the water pump drive pulley, but not snap it off. Those puppies are a healthy chunk of hardened cast iron.

bigtone is correct about holding the sprockets and chains in time by using tie-wraps, but the job is still no picnic.

dalamak
02-26-09, 04:01 PM
I have changed out cams , with the motor in the car. Not bad at all to do . Tha hardest part was puting the valve cover back on. Most of the time its been the front Int cam with the water pump drive brocken off, because the person thought that they could just slide it off and end up breaking the end of the cam off instead. Which cam or cams did you need to change ?


I was thing about making my SLS motor a STS, so which cams would that be?

Submariner409
02-26-09, 04:57 PM
Dig around in here and find a thread from a couple of months ago, posted by AJxtcman, giving all the specs for all the different year SLS and STS cams. A new set of 4 cams and lifters will cost you around $1500, and the engine design was changed in 2000, so you need to watch that, too (roller cam followers with static hydraulic lash adjusters vs. the older direct-acting hydraulic followers).

Don't forget that the two cars have different final drive ratios and different PCM engine/transmission programming. A set of STS cams controlled by a SLS program/final drive would be practically useless.

dalamak
02-26-09, 06:03 PM
Dig around in here and find a thread from a couple of months ago, posted by AJxtcman, giving all the specs for all the different year SLS and STS cams. A new set of 4 cams and lifters will cost you around $1500, and the engine design was changed in 2000, so you need to watch that, too (roller cam followers with static hydraulic lash adjusters vs. the older direct-acting hydraulic followers).

Don't forget that the two cars have different final drive ratios and different PCM engine/transmission programming. A set of STS cams controlled by a SLS program/final drive would be practically useless.

Thanks, I read that post can't remeber off hand if it the intake or exhaust that are different, I got a buddy whose a tech at a dealer, probably pick a set up from him, and just replace lifters new