bennettrp

I'm about to undertake my major mod of the year, AFR 205 heads, LG GX3 cam, com cams push rods and underdrive pulley. I already have purchased new head gaskets and a new crank bolt, but am curious about what else I'll need. I'm seeing some subtle diff's btw the ls1howto.com and the shop manual. Can any speak to below (do I need them?):

Intake manifold gaskets
Head bolts
front main seal
exhaust manifold gasket
any other gaskets/seals needed

thanks

Blue02ws6

You don't need new intake gaskets, or front main. If you want new exhaust manifold gaskets you can but not required, if you get new ones get the GM metal ones, they work the best. How many miles are on your car? You might want to get some new ls7 lifters @ $99, a ported oil pump, maybe a timing chain. I would put in some new spark plugs while it would be easy. You will need coolant, power steering fluid, and I would change the oil also. Start it up with the old oil and then change it.

bennettrp

Thanks, Blue.

C5 has 13k miles. LG headers last winter with new gaskets. I'll check out the new lifters. Already have the plugs and new wires, so they will be new on install too.

Was thinking that oil pump and timing chain are pretty new to replace.

mdhmi

What Blue said + a 100 shot of juice. :o

Congrats on the AFR's and LG cam. That's going to be a very stout NA combo.

Blue02ws6

13K, well you shouldn't need any gaskets except for the head gaskets. Your lifters should be fine also. Some people like the high pressure/high volume oil pumps but it is not mandatory. You really don't even need the new plug wires, the stock ones have been proven to be great and last a long time. They are so short that there isn't much to improve on over factory. Aftermarket ones look nicer though.

vettenuts

Yes, new front seal. The front seal has been re-designed and should be changed. It is installed dry.

If you put the LS1 timing chain back in, big mistake in my opinion. They are weak and known to fail. You are increasing the load with heavier springs and more lift. The LS2 timing chain at a minimum should be used. The Katech is a much better chain. You might also want to consider adding the timing chain damper if your block is drilled for it. You will need o-rings for the oil pump if you change the chain, get three or four in case you have a problem. They are cheap and if you pinch one you will be dead in the water.

You don't need new lifters, but if you are going to put them in, the Morels are specifically designed for aftermarket cams due to the way they are internally oiled because they sit lower in the hole. Superior internal parts and bearings as well, but you will pay for them.

I would also change the intake gasket. It will be compressed when you pull it off and likely full of crud as well.

Get some rubber vacuum caps from Autozone or somewhere like that, you can use them to cap the lines on the PS pump. I only lost two tablespoons of PS fluid when I did mine.

You need new head bolts as well, and an angle gage. Don't re-use the old head bolts. You will also need new AIR pipe gaskets on the exhaust unless you have removed this system. I also changed the o-rings on the PS lines and the dip stick tube. Not sure what year your car is, but the lifter retainers might also be considered. In the 01/02 time frame there were some bad ones out there, they are stamped on the bottom with a "10". I found one in my car and changed them all. I am assuming you have a method of installing the harmonic balancer without using a bolt. For less than $20 you can make an installation tool that won't damage the threads. You might also want to look into the ARP bolts for the cam sprocket and the cam plate. A new timing cover gasket should be used as well.

Some people re-use a lot of gaskets and then have issues later. You have already spent probably $3K on parts to install, I wouldn't try to cut corners on the gaskets and such. If you get even a minor gasket leak it will be hard to find and could affect tuning later. Choice is yours really.

Good luck, it should scream

94legaleagle

Great info - I'm posting now so that I can find this thread in about a month or so when I start my winter project!

Rhode Warrior

Don't forget the assembly lube and loctite.

Rhode Warrior

It's also a good idea to seal the knock sensors while you're in there. Hi temp silicone will do the trick.

Another good tip, there is a very small vacuum hose on the rear of the intake manifold that controls your A/C. It is a bitch to put back on. The best bet is to extend this hose and re-assembly will be a snap.

FrankTank

Are you planning on using the stock rocker arms? Make sure you measure your valve geomtry, push rod lenght, maybe you already know this...just wanted to throw it out there.

You'll be very happy with the AFR heads, they produce great HP.

vettenuts

Yes, Redline contains no solids and dissolves very quickly in oil. It is a great assembly lube. I used it on the top of the valve stems and the top of the pushrods. I also filled the pushrods (after thorough cleaning inside and out) with oil. You can see the Redline Assembly Lube in this photo (red stuff).

bennettrp

Thanks, Guys. Some great points made here.

Appreciate all the advice. WIll incorporate suggestions into my mod "party", which will happen in about a month.

GOt a lot of eyes looking at this mod. Most think I'm nuts for playing with such a new C5. Especially since this is my wife's DD and my weekend toy.

This is gonna be fun. And I cann't wait to see the results.

noobzorta

locktite, torque wrench , ls1 spec book , arp headstuds if you want extra protection (nicer also), arp exaust manafold studs (verry nice, dont have to worry about pulling threads). You can re-use the stock exaust manafold gasket, the gm MLS gaskets seal better then most if not all aftermarket gaskets. If you have a aircompressor, use a airhammer and your old balancer bolt (cut it down a bit) and push that balancer back on with it, then use a new crank bolt and tighten verry hard, use a 3ft jackhandle and give it hell.

Any questions, just ask.

zeevette

I didn't have the right size metric socket for the crank bolt, and used a 15/16 SAE. It fits perfectly. Also go get a longer bolt to install the crank pulley. You can find them at a fastener place, and the size you'll need is 16m by 2.0 thread pitch, and 140-150mm in length. Also a couple of heavy washers, and you'll be in business.

nwdanner

Danger, DANGER, DANGER!!!

bennettrp

I just got a line on a brand new dyno right close to my house. Seems as tho they charge $100 per hour. Was wondering if it made sense to see what C5 puts out before and after mods.

Is it worth the $100?

I've never done a dyno before. Never even seen one. Anything I should be watching out for?

I'm also of a thinking to get the LG mail order tune, since its their cam and they have probably done a bunch of these mods. Any thoughts on that?

Tourmgr1

Great info here.

IFLUBYU

If you dont get a new timing set, at least replace the chain with a hardened or LS2 chain. Degree in that cam man, do it right.

water pump gaskets are a good idea, but not necessary.
A three arm puller for the pulley, a two arm puller for the crank gear if you go with a new timing set.

Good Luck!

Check out my page if you want some more good pics of the process.