92silver964

Thanks for your friendly replies. I've been thinking about the heater bypass, but am concerned about the removal of engine heat under high temp conditions. Don't recall seeing a comment on that. I guess you won't know until the warmer months come along? I like the intake duct, but have the same concern as others that rainwater could enter. Thanks for the link.

Enjoy Barthelona! (I was told that's how it's pronounced there?)

J richard

if anyone needs one of these I have one sitting in a box

H964

i have a steve wong chip for sale as well, never installed
pm me if interested

Lorenfb

"why do you think hotfilm technology was developed at all since the barn door flap is so clearly superior (ahum!)?"

Do you know, maybe not and you are guessing at the AFM being less effective?
Actually, the key benefit of an air mass meter is its more precise measurement
of air intake (mass) for emissions control. And by measuring air mass no correction
is required for altitude changes. Additionally, beyond a certain load (~70%), the
AFM is not effective which requires a full load throttle switch input to the ECM,
which results in inaccurate fuel metering (mainly emissions). From a reliability
standpoint, though, the old AFM has turned out to be more reliable than 993/996
air mass meters. Just ask a few Porsche dealers how many AFMs are/were stocked
versus air mass meters.

My statement:

"The second statement contradicts first one, as a turbo or bigger bore does utilize more energy (fuel)!"

Your statement:

"No it doesn't !!!! As stated a turbo or larger bore makes the engine inhale a larger volume of air allowing a larger volume of fuel to be injected and be effectively burned"

They say the same thing:

utilize more energy (fuel) - to effectively convert (@ proper AFR) an additional amount
of fuel (energy) than could be converted with normal aspiration or an original bore

utilize (per Webster's Dictionary) - to make use of, convert to use

Bottom line: Ridiculous to have an issue over semantics.

DWS964

Thanks, Loren, for the best recommendation of all: "Have fun"

We are all engineers, degreed or not, and thus wish to improve our cars. Improving power, speed, cornering, braking, safety, reliability, appearance, operating cost, environmental impact, longevity, the nut behind the wheel, .... all for the sake of Fun. Without the improvement mentality, we would all be satisfied driving Model T Fords.*


*(BTW, my dad and I once owned a Model T with a Roof SOHC 16V head conversion, Ruckstel 2spd axle, underslung, rocky mountain brakes, ... = Fun)



Have Fun, Be Safe
Darrell

choogh

OK... read ALL the posts... do the bloody things work ?

HoBoJoe

Quick search:

https://rennlist.com/forums/964-foru...-for-a-c2.html

Strega(UK)

All I can say is that mine does. I can pull away from my mate who has a rebuilt stronger engine against my old smokey one.
We had them dynoed and mine despite needing a rebuild was putting out 275bhp, his was 247bhp. Only real difference was the hotfilm.

springer3

The $64,000 question. The answer is no. Don't waste your money changing the air flow meter - any gains come from timing and mixture changes, and those are available with the stock air flow meter. If the stock air-flow meter breaks and cannot be fixed, it is probably cheaper to replace it with after-market, and then you should buy one.

Tango635

I've read this entire thread.

The Ney sayers have been posting theoretical arguments and asking for data, yet have not provided any themselves.

Several Yeay sayers have provided mostly circumstantial evidence (butt-dyno) with the expection or TR6 whom provided only peak dyno results, showing a modest gain. If chart was posted, i did not see it, sorry.

A while back I was considering a chip too and asked the same question, "does it work". I finally talked to someone that said, "yes, they do work because my track times have improved". The guy was a DE instructor so i took his word for it. Yes, i know, circumstantial evidence, but i think lap times might be a better indicator than a couple of dyno runs. I know, I know, a lot of variables, maybe more than the dyno.

Bottom line, I think the Wong chip will give you a modest gain. Buy it, try it, if you don't like it, return it. Also condsider weight loss as a mod, it might be cheaper.

Arrowhead

I believe that there is no better way of measuring hp than a dyno. It gives you hp readout, torque, afr, and at what rpm things are happening. I give this posting a to the Yeay's due mostly to the previous posted dyno run (sheets). HP cost money. There are race car owners out there that are willing to pay $1,000. a hp

springer3

I agree. My ney-sayer comment was related to the hot-wire air flow sensor giving real gains not available using the stock air flow meter. The post showing dyno-documentation that the stock AFM system does not restrict a 300 HP 964 engine is here:
https://rennlist.com/forums/964-foru...-993maf-2.html Look for the NineMeister post at the bottom of page 2.

PNine64

So, if I do the cat delete, primary delete, and Steve Wong best case I gain some decent hp. Worst case I'm out a few bucks. Are there any other draw backs.

I like the CF intake but see there are concerns with water. Is there no drain in that set up? If not, seems like drilling a small hole at the bottom would do the trick.

Down the road I'd like a light weight flywheel (when I'm in for a new clutch). Does this require a new chip or is that already programmed in? I don't think there is a charge if that needs adjusted...right?

Tango635

The main drawback might be slightly worse fuel consumption. Some might argue that more fuel equals more heat and more heat equals less engine life. That is theoretically true, but in the real world i don't think you'll see it because you're not adding that much power. In the case of this particular mod, reliability depends a lot more on how you maintain and drive your car. If adding the chip makes you go from driving like a grandma to drag race at every stop light, that will affect your car more than the chip itself.

Talk to Steve Wong about your questions.

Lorenfb

"Are there any other draw backs."

This was posted last August on this thread:

All "performance" chips are basically the same, with many copies of others', essentially just
"pushing" the timing and requiring higher octane levels (which in most cases isn't available).
Finding the desired higher octane level is the most obvious issue with using a "performance"
chip.

Most are unaware of the problematic issue with using a "performance" chip in an air cooled engine,
i.e. the total cylinder head temperature is always increased by ambient plus the additional temperature
rise caused by the "pushed" timing. That's not the case for a water cooled engine, e.g. the 996. With water
cooled cylinder heads, the temperature is held fairly constant over a wide range of ambient temperatures
and engine loads. This is not the case for the air cooled 964/993 and as such is more prone to
detonation during hot days or during heavy engine loads, e.g. uphill grade and/or hard accelerations.

Additionally, the 964/993 head design has the inherent detonation problem which was reduced by
the additional spark plug. If one of the two fails or is weak in its effectiveness in igniting the charge,
detonation will occur because the normal timing is already "at the edge" initially without a
"performance" chip timing change. All later Porsche engines with their redesigned combustion
chambers (less prone to detonation) now use a single plug. Although the 964/993 DME ECMs have
cylinder head temperature as an input, once the engine reaches operating temperature that input has
basically no effect on either the fuel or ignition maps, i.e. the cylinder head temperature sensor is
essentially ignored once it reaches a maximum cylinder head temperature value and is not a "linear"
variable as in late water cooled engine management systems.

Users of "performance" chips in the earlier 911 3.2 Carrera ('84 - '89) are even at greater risk
than the 964/993 user as the 3.2 engine is single plugged and lacks the knock sensor control
of the 964/993 DME ECM. Those engines have no margin of safety once detonation occurs
and drivers most likely would not hear the sub-audible detonation, notwithstanding the typical
engine noise of the rear engine air cooled Porsche.

The result of the additional engine temperature rise results in potentially sooner detonation and the
knock sensors retarding the "pushed" timing for a net loss in torque. Some "tuners" use hyperbole
such as "the chip AFRs are tweaked to reduce head temperatures" which has essentially little to no
effect in reducing the increased combustion temperatures to avoid the new detonation point,
i.e. it can't really compensate for the basically uncontrolled ambient temperature effect.
That's the reason Porsche went to redesigned combustion chambers & water cooled heads,
e.g. 962/959 to allow greater compression ratios and timing advances in the '80s for race engines.
That's also why all subsequent, to the 993, Porsche engines were redesigned and use water cooling,
which additionally facilitates an emissions control system. Thus, the ambient temperature issue was
essentially eliminated and the cylinder head temperature became a controlled variable.

As with most automotive "performance" products, few if any of the marketing data relate to the
user's the trade-offs/risks involved in using those products. Furthermore, many promote the products
by indicating that the OEM vehicle producer was "overly conservative" (classic) in the performance
development resulting in "tuning" potentials for adding performance. And then there's always the
"evangelical" users that usually don't know the risks or fail to understand them and become
"sales advocates". When one "looks below the surface" of most easy to sell "performance" products,
one finds major issues.