Boxster intercooler???....

[efahl]

pk2 wrote:
Somewhere I think it was you who said the bottom end of a 2.fL could handle 350 hp or more. It’s my understanding (anecdotally) that most people who overboost these things that blow their motors do so as a result of insufficient cooling at the top end…detonation.

Hi Peter,

My ~350 number is only a guess, based on experience with Audi and VW bottom ends (80-100 HP per hole, before rods bend), but none with Porsche's. I'm assuming that Porsche builds solid cranks and rods like their friends across town.

I would concur, most broken forced induction motors happen due to detonation, which might cascade into pre-ignition or maybe just break stuff directly.

I’ve been doing tons of homework and figure with WI, progressive or better, 270cc/min nozzle, 100/150 psi pump, 20-30% meth., injected right by the opening of “spider” manifold would do it for the cooling (no?)

Yes, water/methanol injection will do a good job of cooling, with or without an additional intercooler. This alone can net some significant HP (go play with my turbo calculator for any generic engine and just add a bit of water injection to see how density increases -> HP increases).
http://www.not2fast.com/turbo/glossary/turbo_calc.shtml

(Also read the caveats on the math I use to model the water injection so you don't get too optimistic:
http://www.not2fast.com/thermo/water_injection/opt_mass.shtml)

Pulleying down from 2.6 dia. to 2.5 would put me at about 288 hp (from 260 approx). with the super operating in it safe rpm, zone (14k rpm’s). A 2.4 pulley would put me at about 300hp. But my super would be at 15.3k rpm’s (in a 14k-16k- iffy zone).

Only issue I can see is diminishing returns, the super taking more hp than it can contribute at high revs.

You need to worry about loss of efficiency with higher revs, too. Here's a graph of the older, much less efficent M62 (the Eaton guys were going to send me newer maps, but I never followed through with them, oops) showing temperature change as a function of charger speed, and you can see it is not linear, but increasing faster than the speed does. At some point, the compressor efficiency is such that spinning it faster merely makes the charge hotter and nothing else, so at that point you are way beyond diminishing returns.




P.S. I picked up a EGT (exhaust gas temp) guage an sensord and a wideband


More data is always good, do you have a way to datalog the EGT and lambda along with some other engine parameters (RPM, throttle position and that sort of thing)? Analyzing logs is so much easier than trying to look at gauges while you're driving (but then, if you make a video of all the gauges, you can do a fair amount of "log analysis" that way).

Eric

[pk2]

Originally Posted by efahl

More data is always good, do you have a way to datalog the EGT and lambda along with some other engine parameters (RPM, throttle position and that sort of thing)? Analyzing logs is so much easier than trying to look at gauges while you're driving (but then, if you make a video of all the gauges, you can do a fair amount of "log analysis" that way).

Eric

Thanks for exhaustive reply. I just wrote Gary quite the missive (post here) on my O2/egt/boost etc plans. Give it a read if you can stay awake through it. Like to respond to your notes but I gotta sleep.I'll Give it the twice over it deserves ASAP.

Thanks much

PK

[Gary in BR]

PK,

I'm with you on the PHD, I may only be at masters level.

I still have not decided which way I am going to go the options are much larger than I expected.

I do know that the way we keep modifying these engines we are going to need something to ensure things stay at a safe level.

[pk2]

Originally Posted by Gary in BR

PK,

I'm with you on the PHD, I may only be at masters level.

I still have not decided which way I am going to go the options are much larger than I expected.

I do know that the way we keep modifying these engines we are going to need something to ensure things stay at a safe level.

Love to hear about these "options" that you got up your sleeve. As for safety, I think it’s really a question of do diligence. In short , keep the top end. From burning up. I have yet to hear of any bottom end catostrophic failure due to forced induction. That’s why I’m going to be monitoring everything I can.

Regards, PK

[Gary in BR]

Originally Posted by pk2

Love to hear about these "options" that you got up your sleeve. As for safety, I think it’s really a question of do diligence. In short , keep the top end. From burning up. I have yet to hear of any bottom end catostrophic failure due to forced induction. That’s why I’m going to be monitoring everything I can.

Regards, PK

The options I was reffering to are the options on gauges and dataloggers.

As of today I am going to go with VDO boost and Oil pressure and Turbowerx on board diagnostic tool for my a/f ratio.

As far as future options on the car....
I have not decided whats next.

[pk2]

Originally Posted by Gary in BR

The options I was reffering to are the options on gauges and dataloggers.

As of today I am going to go with VDO boost and Oil pressure and Turbowerx on board diagnostic tool for my a/f ratio.

As far as future options on the car....
I have not decided whats next.

Hey Gary,

Nice that Turbowerks provides you with A/F stuff, sounds like a very well sorted out and integrated system. Can’t go wrong with VDO either.

“As far as future options on the car....” That’s the spirit…I’ll be hot on you heals..

Regards, PK

[Gary in BR]

1st incarnation of the gauges.

I need to make a trim piece for the gauges. That will be my project next weekend. The trim for the ac controls was bought last week but it has not arrived yet. I will post pictures again when the trim gets installed.

After driving the car the boost gauge is so much easier to read high in the dash instead in the 3rd cubby hole.

When ever I install the AF display I will mount it where the radio is now.
And the radio will go into the 3rd slot.

I also painted the silver trim around the radio black today. There is still too much silver in the radio. That will be next months project.

As far as date logging I think I am going to go with http://www.autoenginuity.com/index.html
But I clicked on this board sponsor today
http://www.durametric.com/
these seem to be very similar products. I am going to do so Googling and see what I can find about the two of them.


Sorry about the cell phone picture. But the quality camera is sitting on my desk at the office.

Moving the AC control was a bigger PITA than I thought it would be. But I am happy with my placement of the gauges.
Whenever I get the A/F meters in I may do a double DIN Carbon Fiber panel but I have time to think about that one.

The next step on the mod front.......
I am going to delete my only pair of cats and install a set of electronic cutouts for the exhaust. I will be able to run almost complete straight pipes or quiet it down for when my wife is in the car or that cell phone rings. The only question I still have is weather or not I will run the cutouts via boost or a switch.
With this mod Turbowerx feels I will getter faster spool and possibly a little more boost.
The exhaust mods may be 45 - 60 days away it all depends on my mechanics schedule.