Valve srings help?

[Blackdimonds]

Hey all, I will be doing a bunch of work on my SC this winter, and part of the work will be a leakdown test and valve job. I started to hear a little tapping noise in the fall, and I think it is time to check the valve spacing (3200 miles on a total rebuild so far). I also noticed a small amount of bluish smoke on startup lately. I am doing a leakdown test to see if there is really a problem. My question stems from thinking about possibly installing racing valve springs. The car is driven hard in autocrosses and DE events, as well as future club racing. My question is, can I replace the valve springs with the engine in the car, while checking the valves?

Thanks in advance,

[Early_S_Man]

Yes. Hose and fitting like compression gauge, but with air chuck. There are two separate tools for removing intake and exhaust valve sprinfs ... because of mounting stud locations. With engine at TDC firing point and in 5th gear, with emergency brake applied ... apply 100 psi, and attach the spring removal tools. BE VERY careful NOT to lose the keepers down inside the engine!!!

You will be installing the racing/sport springs at the same installed height as your old springs ... unless you go to the trouble of changing the shim 'pack' and resetting each valve with the factory valve spring height tool.

You may want to check with Andial or Jerry Woods about the intstalled height of the 'sport' spring sets. Changing those shim 'packs' would be a real pain with the engine in the car!

[derkpitt]

What about the old rope trick?
Shove a rope down the spark plug hole, manually turn the motor over. Until the piston pushs the rope up against the valves.

[Oldporsche]

I have used both.

In the case of the rope, I used cotton sash cord.

I used a bit of epoxy on the end of the cord to reduce the chance of a lot of lint being left in the cylinder.

Good luck,
David Duffield

[Blackdimonds]

Thanks for the help guys.

[john walker's workshop]

the springs from AASCO, which are probably the same ones you get from woods, need the steel seat machined on a lathe to enlarge the seating area for the center spring.

[Blackdimonds]

John,

Is this to say that I can't go to racing springs with out removing the heads for machining? Also, what would a shop generally charge for replacing the springs with the OEM style? I'm all for doing the job myself, if I'm getting a good upgrade and I don't have to do any head removal.

Also, because you're the expert around here, what would a shop generally charge for doing torsion bar replacements (front and rear) minus the cost of the bars and bushings?

Thanks,

[john walker's workshop]

blackdiamonds. that's coal isn't it? anyway, there are springs out there that don't need the seat machined. they'll tell you. the seats just sit under the spring. you can grab them with a magnet if you need to remove them. doing all the springs with the engine in the car would be a pain. engine removal would be best. a shop would charge about 8 hours including engine R+R and valve adjust. baum and assenmacher sell the spring tools, as well as performance products, and maybe pelican too. i usually do them at TDC without air pressure, because the stem seal grips the stem, and keeps the valve from moving much, and it's easy to pull it back up with a small screwdriver in the keeper grooves. TDC (piston up) keeps the valve from falling into the cylinder if it did go down too far.
the torsion bar labor would be around 4 hours if everything went right, (like the bars coming out easily). then a 4 way alignment would need to be done for around 2 hours labor.

[Early_S_Man]

The spring seats are #12 in the following diagram: