O-ring the head, use Wide Fire Ring gasket. While the head is off, refresh it with someone that does good seat work. Stock studs are fine..

 

Head studs are an expensive proposition, but worth the investment. I built my motor with completely stock turbo, boost, etc. and dropped in some Raceware studs in case I do go boost crazy some time. Also did a WFHG. It cost me $185 to get the old studs out and the Racewares were like $225 from Lindsey IIRC.

Figured better be safe.

 

John (fast951): If that is the case, then i was mistaken regarding the WFHG and it was the MLS headgasket that was recommended NOT to o-ring the head?

 

Correct Hos

 

My mistake, sorry, i mixed up the WF and MLS HG.

 

I also have a 3 angle cut valves... the guy doing the work said more than that will mean excessive wear, good to do if I was refreshing the engine every season or so, but not otherwise... opinions?

 

I opted to use raceware studs and a widefire gasket, with no O-ring. I am a sucker for official porsche advice and did not want to re-use the original headstuds (manual says not too). Also, since I sometimes run 23psi, I figured it was a good investment to use studs that would survive future head gaskets. So far, so good. It's held tight for over 2 years now (several 23psi dyno runs later)... (knock on wood).

 

Get the rod bolts for the $125. They are worth it and easy to install, but you need a press. If you have access to a press, you can remove the old rod bolts in less than 5 minutes. Once they start to move, they will pop out. The new ones press in very easily also, just make sure you seat the head of the bolts all the way down on the rod . ARP studs are a great investiment. ALthough my old rod bolts looked fine, the bearing caps would not slide right on to the rod, they kind of hung up on the threads of the old rod studs. Once I put the ARP studs on, the bearing caps slid right over the new studs. So there was obviously a very slight bend in the factory rod bolts.......

And they are reusable.....

 

hmm. Great responces guys thanks....cause this is something new to me and I need all the help I can get. Well I guess the ARP's are a no brainer now as well as the widefire. I don't know about the o-ringing. That would take a extra week(shipping) and I really really just want my car back running well. hmmm tuff choice.

J chen the 400rwhp is just a minimum estimate on power after the turbo get's done. My end goal for the car is 400rwhp in all reality the car run's so well with just bolt ons(new motor,tranny,rear end,ect) that I expect to make more power than that at 23psi with the to4e. I can't wait to pull the old turbo and find out exactly wtf it is.....weither it's just a rebuilt stocker 26 or some kind of cheeter creation.

How much would it cost to cut the valve seats....if I was going to decide to ship the damn thing off and have it o-ringed I might as well look into doing the seats if it gives as big of benefit as you guys say it does. In all honestly I will be happy either way. If I decide down the road I just want more power and really want to build the head(porting,valve cut,o-ringed,milled,ect) then I guess that would be the better time.


Unless ofcourse you guys come back and tell me it aint all that bad in price.lol. Maybe someone here has a built head they would take in exchange for mine along with some coin?

 

Check with Danno, he's got some very trick stuff.
Might be worth your while.

 

I remember fast951 stated he has a WFHG with an O-ringed head on a tracked car and didn't have any problems. Also, I remember Tony G stating that a lot of his racing buddies were returning to the factory studs after using ARP and raceware studs. It appears the factory studs were giving better service. Do a little searching and see what turns up.

 

In response to the note on rod bolts - When replacing the rod bolts you should have the big end resized or at least honed.

Chris White

 

If the Head is off, then have the Valve sealinh checked. As simple as have a vacuum check on each port. If the sealing is not good, then have the seats repaired. At this point, decide upon the type of seat angle to have done. You will have to talk the person doing it. They will be able to tell you what angles to have cut. It does help the flow, but there are considerations to keep in mind. If the seats are low in the Head, then this will dictate the top angle etc. BTW, most sealing angles are 45 not 30. Even on radius curves, there is normally a 45 angle. The Valve is cut to 45 also. The back cut on the Valve along with the bottom seat cut really determines flow. I know on the 944 Heads I have had done, the Bottom angle made a 15 CFM difference. Even left the sharp step. This helped.

As for porting, don't bother. Maybe a simple polish to remove the casting flashings, but unless you do some other things, the Intake will always flow way more than the Exhaust. Spend you $ somwhere else. When you need more Head Flow, then you need to look at the 944 NA head and have all the bells and whistles added.

As for the HG. Use the MLS type. Use good fasteners, install them properely, NO LOCKTITE, and make sure the Block threaded bores are clean. Use the ARP grease on the studs on installation, not LOCKTITE. Then handtight only, and fit the MLS Gasket carefully watching out the center layer does not shift. Then torque down the head as per factory spec's. You can even goes lighter on the torquing if you wish, as the MLS will not collaspe like the fibre type does. Remember, with the MLS gasket, you will not have to retorque the Nuts. Another good idea is the stepped Wahers available. These help stop the Head from collasping inward at the stud holes under compression.

before you do any of this, make sure the Block deck face is clean, and flat. check with a straight edge front to back, corner to corner and across. Do the same for the Head.
If you want to send me an email, I can tell you way more, and where to go, who to call and where to get all of the parts. You will not be disapointed.