I popped the head gasket on the black hole known as my '88 951. <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />

What head gasket would you guys recommend? I'm running around 20# of boost, at times a bit more. <img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />

Also while the head is at the machine shop I was thinking about doing a valve job and some porting - any thoughts on doing this?

Thanks,

Alex
P.S. Did the search function get removed?

 

Use a WideFire head gasket.

Don't spend you money on porting unless you spend big bucks, to really do it right.

Doing it right includes all the other things you'd have to do to take advantage of a big flowing head like:

Free flowing turbine (Garrett).
Big cam.
Different intake manifold

etc.. on and on and on.

I'm not saying it's a bad path to go down. It's just that to take advantage of a good head, it takes a lot more than just the head ($$$).

Also... to really to a head right... you don't use a turbo head. You use a normally aspirated core so that you can port the exhaust ports (which you can't do on a turbo head).

 

I didn't see a turbo listed on your list of mods.

If that's the case... save the money on the head work and put on a bigger turbo instead.

 

Alex, thanks for the reply. I'll give Ed a call and maybe go see him tomorrow.. let me know if you need any help..
Dave

 

I've got a used (500 miles) Huntley Racing FMJ-OR O-ringed full metal headgasket with Viton coating. It looks brand new. Your for $140 (retail is something like $175ish). Email me if you want it.

 

Interesting info on using the NA head. My thought was to do the head now since it's off. My long term plans include an intake and a turbo. Right now I don't have the funds for either as I have put $3k into the hole since January. Now this head gasket thing. So I'm replacing my lightly cracked exhaust manifold since the head is off. Hopefully the turbo will self destruct just before winter. Then I won't have to make an excuse for my wife when I tell her I need to spend $2 on a turbo.

I'm being quoted $400 for just a valve job, waiting for the quote on the porting. The machine shop will give me a price on that once they have the head.

So the NA head will bolt onto the turbo block? Any mods required to do that?

Thanks again,

Alex

 

clubracer6

The n/a head should bolt right on.

Also... I would advise not to surface the head unless it's not flat and out of spec. The last thing you want to do is to raise the compression.

Again.... don't bother porting the head. Do the valve job, guides, and seals (and possibly springs if they aren't in spec), put on a widefire head gasket, and put it back together.

Also.. make sure you put the head on with the headers already bolted on... in case you didn't already know that short cut.

One last thing... you should, since you have the head off, have it "O" ringed.

 

you're running 20+lb on a STOCK TURBO???

have fun burning a valve or piston.

 

I ran 21# on a stock turbo (with race gas). Din't burn valves or pistons. Try that with pump gas (particularly 91 octane crap), and watch the motor gernade <img border="0" title="" alt="[Wink]" src="wink.gif" /> ... unless you're running something like -20 degrees of total timing advance (or retard, rather). Either way, if you dyno the car @ 20+ psi, watch as the HP falls on its face in a very big way around 5500 rpm or so...

 

What's a safe boost number considering the amount of mods. I thought if you had enough fuel it was safe to run big boost. It should be interesting to see what everything looks like w/the head off.

Thanks for the heads up on not surfacing the head.

 

I ran all season at 19-20 psi without an O ringed head and had no problems. I did use a 50/50 blend of 93 and 110 octane. Under boost the timing was set at 20 degrees, Tec3.

Alan C.

 

Here's a fact... no matter how 'correct' your fuel curve is, if you run too much timing you WILL ping, and you could therefore gernade your motor.

 

rcldesign won't the stock turbo be out of its efficience range.you would be blowing hotter air in the engine.the end result denoation. unless you were running 100 octain gas? but youre hole air charge would be way to hot.

 

Clubracer6,

Send your head to Lindsey Racing. They did a fantastic job on my head. Talk to Dave about what modification is best for your application. I found Dave to be straight forward, informative and honest. He did not try to sell me more than I needed or would make a difference with my setup.

I agree with Tony G, wide fire head gaskets work well. I also had Lindsey install o-rings in my head.

Check out their website to see the vast services/products they provide. <a href="http://www.lindseyracing.com" target="_blank">www.lindseyracing.com</a>

I have no affiliation to Lindsey, just an extremely satisfied customer.

 

My own opinion is to go with one of these headgaskets. They are about 2x the money, ~150 but in my opinion worth the extra $$
<a href="http://www.archcartpro.com/users/dkhajavi/index.htm?sess=ccd6721c2755398ce9f5777999c25f2b&time=1052096382" target="_blank">Huntley Head Gasket</a>

<a href="http://forums.gururacing.net/viewtopic.php?t=43" target="_blank">Guru Racing Head Gasket.</a>

My theory is that factory gaskets are fine until the engines are opened up. Then, the mating surfaces are such that sometimes a stock gasket won't last long. Case in point: Many have reported multiple head gasket failures after engine rebuilds or HG replacments.

I'm about to change the HG on my 86 track car. It will be one of the above. There is just a lot more material around the cylinders and jackets.