333pg333

Ok so what parts are so much better on the more recent Porsches than ours and what can we do to redress the balance? The parts that I mentioned above that were suspect under higher loads can be upgraded to a greater or lesser degree. Again, what are the Jap cars using here? Are their gearbox's and drivelines in general so much better than ours?
Don't assume that you've seen the end of the line in power with ST's motor, not just yet. That was an 8v 2.5L. There will be motors larger than 3.2L using 16v heads (some of them worked over too) that will produce some pretty handy CFM's plus they will be running some pretty big (for our little world) turbos. They will have standalone engine mgmt and should make 700hp on their ears if not a fair bit more.
Not everyone is looking for a car that will do glory runs on a dyno either. They want something that can be taken to the track so may have to wind the screws back a little for reliability, but what are they facing here?

Lorax

People don't seem to want to spend the money to get the results sometimes.

Everyone wants 500rwhp at 15psi on pump gas with all stock drivetrain componants, and they want it to be totally bolt on and cost under $5000. People need to get past that mindset.

blown 944

My question is has anyone...

sleeved, hardblocked (to the deck),used aluminum rods and chevy after market pistons. Changed the valves to another make and forgot about the ceramic liners with a massive overhaul including welding and reporting. Ran on pure methanol/nitro mix(not nitrous) with a thumper turbo?

If not, there is still a lot of room IMO.

special tool

The power limit of the 944 is the block - and I am using that term lightly.
Other engine tuners are worried about cast rotating assemblies, the casting I am worried about is the one with the freeze plugs in it.

BC

Some 928 people have felt that the strength of the block, more importantly both the towers and the main webbing is the issue. I assume you noticed that the block and the lower half is actually two different materials. Both aluminum based, but in realtity, different alloys.

You have mentioned before that you believe the Cometic actually clamps the tower properly in place, and baring any detonation, where do you feel the weakness is then? The ballooning and thereby cracking of the cylinder? Can I ask, what, in your opinion, is a solution to that, at least on a stock block apart from boring out the towers and replacing with ductile iron?

Also, have you experimented with any aluminum friendly block fillers? It adds weight, some issues with coolant passage, but also it is SUPPOSED to impart some rigidity that the block does not originally have.

I think I may be preparing to get close to where block rigidity will be an issue, so on my 5.0L alusil block I will be putting different girdle studs in, and a special second block girdle/pan spacer that will allow me to attach the pan to the engine directly with no seal, thereby creating even more bottom end rigidity.

Chevy and Ford guys always talk about "Pan Rails" and rigidity down there. I believe it is said that the issue is crank whip, where it starts to try and whip apart the block.

At 60x hp out of a 30 year old 2.5L, you would have to experienced various interesting incremental direction changes - can you share?

special tool

I have thought about that actually - I should have written I believe it "helps to support". I don't think I used the word help, in reference to the mls.

I have experimented with aluminum friendly block fillers - I got a big fat "F" on that report card. How is that for honesty? I do not advise others to use it.

My opinion is that pre-ignition is a killer on these engines.
NOT knock(detonation)
I have lived with knock, but been killed by pre-ignition.
A little knock will lift the head, but the wrong plug, or some carbon on the back of your exhaust valve that lights off at a few degrees past BDC, will kill you.
A change to 8's helped me at 600, and it still starts cold.

I don't usually post my deepest emotional feelings like this, so I will probably delete this in 5 minutes.

BC

Well, I appreciate your candor. People have to realize how far past the orginal parameters even 450 is. Our "Fat Lazy" 928 engines are quite robust in certain places (forged rods, nice strong crank, very heavy 4V heads) and in other areas get "a big fat F" as you say (block strength, oil control, windage control, 7 foot timing belt and an anachronistic oil filled tensioner).

E85, as I have mentioned before, will be my E-ticket to a streetable 700 or beyond. Sure, doesn't sound big, but it is. Alcohol burns cooler, slower, and produced more power in the way it must be utilized because of the stoich numbers (10:1 stoich, maybe down as low as 6:1 rich), and its ability to make more tq at much richer numbers. It will be plentiful in certain states within 3 years, and I already know about three in a 20 mile radius from me. It will allow me to tune not with no regard to pre-ig or detonation, but with much higher ceilings as it pertains to timing, combustion chamber temps, and "boost levels" i.e., CFM rates from the boost-maker (in my case, a vortech, unless I win a big prize at the casino, and the it would be a couple turbos)

BC

And even more so we are talking about open deck blocks with only four studs. The world has moved to 6 stud blocks with closed decks.

333pg333

So by including a deck plate, putting in larger headstuds, pinning the girdle, Cometic h/g's etc...we must be increasing our strength no? As for pre-ignition being worse than Knock, well that's how much I know. I thought pinging preceded knock?
Oh, and by the way, you can get alusil sleeves for alusil blocks. Bet some of you didn't know that???

blown 944

[QUOTE=BrendanC;4846054
E85, as I have mentioned before, will be my E-ticket to a streetable 700 or beyond. Sure, doesn't sound big, but it is. Alcohol burns cooler, slower, and produced more power in the way it must be utilized because of the stoich numbers (10:1 stoich, maybe down as low as 6:1 rich), and its ability to make more tq at much richer numbers. It will be plentiful in certain states within 3 years, and I already know about three in a 20 mile radius from me. It will allow me to tune not with no regard to pre-ig or detonation, but with much higher ceilings as it pertains to timing, combustion chamber temps, and "boost levels" i.e., CFM rates from the boost-maker (in my case, a vortech, unless I win a big prize at the casino, and the it would be a couple turbos)[/QUOTE]

Th tmy friend is what I've been preaching for some time now. I really don't understand (other than availability) why there would even be another choice. If I were to be using anything else at this point I gaurantee I would have had many a HG failure considering the boost I've run.

I'll give you a real world example of how good it is. I tuned a friends blown small block chevy Luv pickup from 11.20's to low 10's in one wedsnesday night by switching from c16 to straight ethanol. No pulley change or anything esle, and it was carburated. I would personally use nothing else.

ST do you feel that if it weren't for ignition related trouble that the block filer would have been OK.? Let's say you could leave out any tuning trouble and just look at strength?

I agree the 4 bolt fasening looks like a potential problem area .

special tool

ST do you feel that if it weren't for ignition related trouble that the block filer would have been OK.? Let's say you could leave out any tuning trouble and just look at strength?



No