Chris White

Head lift and head flex are two different things….
Head list can be dealt with using shorter studs and larger diameter studs. In addition to that the use of a Wills rings will allow for a little movement without failure.

But the best thing to do is to establish a stable mounting point – if the block is flexing you head gasket will fail….its just a matter of time!

The flexing head issue can be dealt with in a couple of other ways, pinning inside the casting can help in localized week areas. Adding more material via welding can be done also.

Duke

It could without a no doubt be a serious improvement!
Maybe a starting point would be to machine both head and block and run Wills rings. Maybe that would be enough for higher power.
But a whole new block would make sense if it were capable of 250 hp/cylinder and keep it sealed. Less than that and it would seem to be a waste.
I hope you proceed with he project!

I thought you weren't too keen on the larger diameter studs?

BC

Blown- I was speaking to a good friend about your situation. He knows I do ethanol as well, and I told him you are probably not detonating very much if at all, so you are not purposely being ignorant of that issue.

He said something very important and I wanted to repeat it here:

When you order your cometic gaskets - do you ask that they emboss the ss inner layer? Normally THEY DO NOT, so the crush for the gasket is only on the upper and lower layers. Fore more strength, you can ask them to emboss the center support layer - and again, they normally will not do this unless you specifically ask.

blown 944

Just the fill, and stock studs at 100#. Trying one thing at a time. I really wanted to see what difference the fill made. I need to put some more time on it to feel like it has made a difference, but so far so good. I won't be turning it up to test it out further right away.

I was thinking about installing the studs and a cometic if it helps, but honestly I think I'd be better off working on the other engine. I was adding it up and I've spent close to 500 for head gaskets recently.

The only further plan I have for this combo is a cam swap. I have some friends renting the track in a few weeks and I might run it and do a cam swap at the track for back to back comparison.

blown 944

Thanks for the info. The last one I bought from Lindsey, I will contact cometic next time. Thanks again

FT_Factorytuned

I have to agree with Chris for the most part, X the welding thing. I simply cannot wrap my head around welding THIS Al sand cast head. Last time I ask, I did not get an answer as to the alloy of that head. And without that info, am unable to anneal and re-temper it post weldment. There is an alternative to trelle, but again does require second op machining. Asymmetric labyrinth seal to seat the fire ring. Some multi layer head gaskets use this principle. The one fellow brings up a valid point. Co-met does a similar thing. But not quite the same.

It may be a better solution to cylinder and head walk than wills rings. These solutions all require proper studs and possibly alternatives to mounting.
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Blown I'm hoping you mean 100nM. for "stock" factory studs. If you have torqued stock factory studs to 100lbft you are compromising them and they will streatch more and more easily. Porsche says 65lbft(90nM) as that is the elastic spec on the factory stud part or the nut or combi of both or of all three being the block thread. There's not any more clamping force generated beyond that or it's to the detriment of something else.
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Chris that is going to cost you thousands. Point cloud is a good way to get surface data, but it' a long way from a solid, and further from a part or much less a working prototype. For the one fellow that wanted to know about cost. It would be the base platform for a 20K$ rich guy/pure race motor with ancillaries.

All these "fixes" at best require machining of one or both, the head and or block.

FT

Tom M'Guinn

I'll be curious to hear your longer-term results with 100 ft. lbs. on stock studs. The world needs pioneers! Raceware warns not to torque its studs past 65 ft. lbs. but on the track they have proven themselves to hold a seal better at 100 than 65, so I'll reserve comment on whether to call you crazy for torquing stock studs so high.

Tom M'Guinn

Raceware warned me against running more than 65 ft lbs. on their studs, but they've been holding great at 95 ft lbs. with 500rwhp. The world does, in point of fact, benefit from pioneers. The pioneers, on the other hand, crash more often than fly. That's just the reality.

DDP

We can't be sure where the factory studs, or any studs for that matter, start plastic deformation. One can assume it's shortly after the recommended torque spec, but they could have figure that torque was satisfactory to seal. Nothing is black and white, cut and dry. I realize we can make educated decisions, but unless someone sits down and does the math, we're all guessing here.

And like Duke said, unless the design of the headstuds is changed, most likely doing a billet block won't make a difference. Not to mention, it's doubtful any of the talkers here will actually complete it, so I'm not sure why it's still being brought up.

blown 944

ran it extremely hard tonight. Made probably 20+ runs at 18 psi. Coolant reservior is bone dry. I think the filler helped tremndously.

I took a couple videos of pulls and one of me getting out of the car and opening the hood when I got home. As soon as I get my new youtube account setup (forgot how to log onto the old one) I'll post them.

Sink or swim, I show it all

dnovak

up late? looks good and I am sure you are a little happier now

reno808

Whats with the porno music?

Great work. Breaking barriers

FT_Factorytuned

Hi Sid, torque out of spec CAN BE a short path to heart burn. Pioneering has been used out of context here. Stupid is not the case either. And coming from a rocket scientist I would expect more as I know very specific standards are in place for rocket motors and vehicles.! Don't think for a minute Porsche and kolbenschmidt did not do the math, nor me for that matter in developing my parts. What we do not know is the material, therefore we cannot know the strength without testing. Why bother Kolbenschmidt / Porsche has already done that and 65lds was stated +/- 4% allowable. Those factory studs and nuts meet a spec for clamping, but are production items. Minimums have been met.

Just know it is not a good idea to do that. If you can't get "it" to work right with the proper clamping force, the problem lies elsewhere. That's the idea...

The multi-layer co-met gasket with embossment, is probably the best place to start, and get a new set of studs and nuts, as you cannot use those again. If you put a dial indicator on those studs I'd bet they stretched more than 50 thousandths. Elongation at yield on tempered studs of marginal steel, is a fairly low percentage of overall length. Again we don't know the steel. But a good test, would be to get a new set of studs, washers and nuts and measure the stretch at proper torque using the proper techniques, would give a good idea. I have never measured this, but will at some point now that I am curious.

Good luck with that.
FT.

blown 944

Ok to keep things in perspective, and to be bluntly clear about why I did it this way...

First did I expect it to work well? NO, I expected it to push the gasket immediately
Do I care? NO, I am building another engine and rep-lacing HG's is not a big deal.
Was it an experiement? Yes, to see if the filler made any difference using the weakest parts in my posession.
Did I tell anyone else this a good IDea to to do with their own car? NO, What I do to my car is my biz.
Were my ARP studs in my posession yet? NO, If they were I would have used them with the widefire.


I'd say it was a success. I once again took it out for a 2 hr drive this morning and ran the crap out of it to see how it went. Again no coolant overflow.

I even turned up the boost a little bit. To around 19psi. Again this is with 11.:1 compression. The MAF reading show about 45# per minute

I think a lot gets lost in my postings about why I do things.

One other thing to note is that since I have owned this car it has not been off the road for more than a week or so. so truly I enjoy it regularly and I don't drive it nicely!!!

There are a lot of intelligent people posting in this thread alone, and I am glad to be able to spark any intelligent conversation. I am always willing to learn. However, I am also willing to test things out on my own dime.

I personally don't think that me doing something different to _MY CAR_ merits throwing around an insult such as stupidity. I do my best to reserve judgement on others ideas and choices. I also speak in the same manor that I would as if they were standing right in front of me. I really doubt anyone here would call anyones ideas stupid directly to their face. But here we have the internet ,and internet kahones.....

Speaking of which...

Ahh Forget it... Age has taught me a few things.......... Have a good day ..I know I am..... ripping around in my hoopty

refresh951

Sid,

I personally really appreciate your "experiments" and I know I am not alone. I also appreciate your openness in sharing results, GOOD or BAD. Your "out of box" thinking is a catalyst for great discussion and it honestly makes this forum a lot more interesting.