I am planning to install a UD pulley on my c6 LS2 for HP gain. It is not my intention to replace the cam. My car is a bolt on only. If anyone has a proceedure for replacing the pulley I would appreciate some help here. How much time is involved for a good garage to do ? Has anyone ever done it themselves. ( Just the pulley not the cam ) Thanks

 

You'll basically be doing a cam procedure - pull the water pump - radiator - fans, steering, and then the pulley. Very involved for only a pulley... Send me a PM if you have any questions

 

whole lotta work for just a pully. I understand if you want it to be bolt on only, but you could slap a cam in there easily after going through all that for that little of a HP gain.

 

I have an SLP underdrive pulley and belt ready to go, haven't installed it, yet. The Spinmonster gave me some scantilly instructions, but I have all the tools to do it, so I'll flounder until I "...get 'er done!". Anyway, he basically said to unbolt the rack and pinion from the main frame and the A-frames, disconnect a couple of hoses on the driver's side connected to it and move it just out of the way to get access to the balancer bolt. After that, use a puller to get the pulley off, mount the new one on with an installer tool and a specified procedure, reinstall the rack and pinion, you're done. Well, we'll see, or if you get it done before me, let us know a more detailed procedure....but my understanding is you don't have to remove all the other stuff to get this accomplished.

 

what about drilling and pinning the crank

 

Yes, I think that is a great idea, too, and I also asked the forum about that due to some people having slippage problems; not too much of a response. I guess there is a special tool for that....it comes with the purchase of a Maggie, but to get it by itself (without the Maggie), I don't know where. But if one had the tool, I agree that should be done at the same time you are installing an UD pulley so it would save any headaches later.

 

you just drill with cordless drill tap pin in

 

Whoa there. It isnt anything near a cam swap. The steering rack is unbolted and hydraulic lines are removed and capped. You dont even have to fully remove the rack. I just slide it to the passenger side and turn it so it is up out of the way. The radiator and the fans do not have to come out. I would remove the TB and the water pump for easy access of a breaker bar for the pulley bolt.

You then use a pulley puller from the bottom of the car. 99% of the time the pulley seal on the front timing cover wont leak. In fact I had more leaks from the timing cover plate not being centered properly because the bottom gasket has to be compressed for the cover to propery align the pulley/seal. My vote is to leave the old one in place. You can get the seal off without removing the timing cover but it takes a while and a creative hook shapd tool I made for the job. The seal is rubbery but has a metal plate around the perimeter where you pull it from. I would be guided by the number of miles on my car.

For the bolt reinstall, first you use the OLD BOLT and TQ it down to 240ftlbs which I seem to always get easily while others say they cant pull it that hard. I wonder why. This seats the pulley. You then put on the new bolt and TQ it to 37ftlbs. I then take a black magic marker and draw a line from the center of the head of the bolt to the 12 oclock position. Then grab that breaker bar again and turn the bolt until it is 140degrees or about between the 4 and 5 oclock positions.

UD pulley went on my car went on the week I bought it and I did exactly what I typed. It took 3 1/2 hours compared to a 15 hour cam swap.

Now a cam swap requires you remove the fan, radiator, fuel rail beauty covers, coil packs, valve covers, all rocker arms, all pushrods, a method to hold the lifters in the up position or rely on divine protection, remove the timing cover plate, remover the cam sprocket, cam retainer plate, shroud removal so you dont have to open the A/C lines and just push te condenser enough for the cam to clear. I would also remove the oil pump but it isnt nec as long as the dots were lined up when you remove the cam sprocket. You can se the oil pump sprocket's dot as long as its in the top position. Before I remove the cam sprocket you can use a black magic marker to mark the links of the chain to the sprockets as extra protection from being blinded by the time you have in the project. Put some bolts back on the end of the cam and slide the cam out by turning it slowly and keep turning it. Dont force it or you will scratch the cam bearings. Once its out, oil up the cam journals on the new cam. Its a hydraulic roller engine so moly lube isnt needed but I use it. Slid it in using some of the bolts on the end as a handle. Rotate the cam so its in the TDC postion of the positons and the cam retaining plate is put back on. 4 bolts and they get TQed to 18ft lbs. The sprocket gets the chain put back on it with the black magic marker marks have the same link on it. If you are changing the timing chain out for a double roller, the oil pump has to be removed and as you back the tiny pick-up tube bolt sucker out, stop and put a thread around it so if it falls out you wont have to try fishing it out with a magnet. Line up the dots and tighten down one bolt on the cam sprocket and they get TQed to 18 too. Next is the alignment of the timing cover and the bttom gasket is going to push on the cover upward so you have to visually see the shape as you tighten it. Using the pulley as the install alignment tool doesnt always work so you have to take it off and look/adjust until its the same distance to the crank all around the seal. 10 bolts (8 front/2 bottom) TQ'ed to 18ft lbs. Install the pulley as described above. Install the shroud, radiator and fan. Install the water pump, and route the belts ac first. Install the TB. Install the rack. Hook up all hoses and hydraulic lines. Fill radiator. Pushrods and rockers install. If you put in a healthy size cam the pushrod will likely be optimum with a 7.425" due to a smaller cam base circle. TQ rocker arm bolts to 22. Valve covers go on as does the coil packs and beauty covers so you can retain heat and lower your HP. Air cleaner, and start proceedure.

This wasnt to be super accurate and i typed it 1/2 asleep so if I left something out, it further illustrates my point which is: that the pulley is nowhere near the size of a cam job (I dont know if this issue is a myth or an exaggeration) and if anyone thinks they are similar I will pay you for the pulley install and while youre in there, pop in a cam for me.

 

I think I know what you mean now. Drill & tap a hole in the side of the
HARMONIC BALANCER then run a set screw in and tighten it up against
the crank. I know there is a woodruff key in the crank that the pulley slides on so it cant slip. The drilled hole is an extra precaution to prevent slippage in addition to the crank key. AM I correct ??

 

There is no key in the crank of the LS series, that's the point of drilling. The pin helps keep the balancer from spinning and loosening the bolt, which can let the balancer walk forward. I've seen that happen on a couple of cars that had cams put in. If they are lucky they notice the massive oil leak before the balancer comes off.

 

If i understand it right after the balancer is installed & torqued down
drill a hole from the front inwards between the balancer and the crank
and tap a roll pin in which would essentially serve as a key like the
engines of yester year.

 

no you drill from the front, put the pin in then the bolt holds pin from walking out

 

You got it! Do it before you install the final new bolt after you use the old bolt to seat the balancer.

IMHO If I was doing bolt on only I'd go with a FAST before I did the underdrive pulley. If a cam is ever in your future (and who on this board REALLY never plans to put a cam in.. ) you're doing the effort twice. The FAST will give you more gain and it's a ton easier to install. The underdrive pulley is a no brainer mod when you put in a cam.

Another potential data point - I've got an underdrive pulley and I've been getting odd "service charging system" messages too.....dunno if they are related. The service charging system comes if I don't rev the engine a little right after starting it, and sometimes it comes when I'm just cruising on the highway. Might not be related to the underdrive but it sure didn't happen until I got the cam and the underdrive.

 

Joe, I do have the fast. I had to modify it as to not mess with the firewall or put extension wires for map sensor. Its now out for porting
& painting. Ill have it on the dyno in a couple of weeks. I thaught the UD would give me a little more yet while its still a bolt on car. Your
very perceptive about what members do in the future. I was thinking about LGM's executive cam with LS3 heads some time down the road.

 

The pin is a 3/16 roll pin.Its drilled right along side the crank bolt. Some
balancers have the starter hole there for a reference point. Just make
sure you have a good carbide bit & use cutting oil. There are kits available but I cant see $100.00 to get. The crank bolt actually holds the pin in.