top end rebuild

mambodave · 03-15-2005, 10:08 AM

Im contenplating a top end rebuild on the 86 951 i just got. car has 135k on the clock... car smokes a little on start up in the morn, but is fine after about a min or so.

Im going to have some extra cash and thought it would be a good place to put it (all other stuff like belts, fluids, maint stuff, cosmetic stuff is taken car of)

A few questions...

1. Anyone have a parts list of things i will replace?
2. How much green will it cost (in parts) if i do the work with a few friends.
3. Short list of steps (i have a manual on the way, but am just curious of the process. I havent opened up a 944 before, just American Muscle cars)
4. How long will it take?

Dave

ae1969 · 03-15-2005, 12:27 PM

If you have diagnosed a valve stem seal failure........ which it sounds like it is........

- Buy a head gasket set. Everything you need is included. (~100)
- You could replace the waterpump (if it has not been replaced). Check all rollers/tensioners, belts.....

If you want to get off cheap. Just buy a head gasket set.
When you pull the head off you will see how much needs to be done to that head. You can probably have it rebuilt locally (new guides ) ~200..... and you are done. The stem seals are in the head gasket set.

blindeye · 03-15-2005, 07:28 PM

Seals leaked after having timing belt and tensioner replaced. Belt broke. Car died. Warranty covered top end rebuild. Bill totalled just under $1500 in Upstate SC. HP gain was very noticable after 183K miles. I didnt realize how much HP it had lost. Now it has that original Uuumphf!!!!

dangerous · dangerous's Garage

I just did a top end rebuild on my 85.5 N/A and may have some info for ya if you're interested.

1&2. I did some price comparing (parts) for this job and compiled a spread sheet. I included pelican, performance products, paragon, tweeks, vertex, zims,pap parts, 9parts,eurowebparts. Included part #'s, part descriptions and prices. I didn't always go with the cheapest price, you've got to consider the quality of the parts too. But I did save hundreds by not buying everything from any one supplier. If you commit to only one supplier, I found the total price varied only a little compared to buying from 3 or 4 different suppliers.

I can email it to you if you're interested but you'll have to double check the parts as mine is a N/A not a turbo.

3. Clark's garage website, factory repair manual, PET program, and even a haynes manual were what I used. I also searched the old posts here and occasionally posted questions. I printed out a few step by step pages from clarksgarage website and brouht them out to the car, the proceedures outlined there are very helpful.

4. have to ask the more experience people here, I took my time.

DannoXYZ · 03-16-2005, 02:45 PM

Are you doing a head rebuild? At that mileage, it's not really necessary. At the least, you should mill the head to ensure a perfectly flat mating surface. Typical practice on 951s with the tuners is to mill 0.050-0.060" off the head to increase compression to about 8.3:1 for an extra 10-15hp. The 2-3 degree retard on the cam also helps in high-end flow and counteracts the diving torque-curve a little.

Count on a full weekend, 10-15 hours for your first time in pulling the head and replacing all the seals that come with the headgasket set. The only seals you won't use are the valve-stem seals.