MAF ; Great 964 Upgrade ! In the TOP 5 ?
12-22-2007, 08:22 PM
#151
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gfunk,
The test results are 53 hp more then the specs for my car . The stock 964 hp specs are 250 correct?
I got 303 on the dyno with about 25+ pulls . That is 53 hp right?
Like i said before I just am happy with a new mod that i have done and what'd to share it with the board.
John made no claims , I did .
As for the dyno test;
I have to disagree with the thought that running my car with the stock stuff, then running it with the MAF would result no good data.
When I run my car with the stock stuff it does in fact become the "blank" And running it with the MAF then it become the "sample". on the same instrument .That data is VALID, I spend a little time in the lab myself .
That test would show a gain , would the gain be the same for every car? NO
But it is a valid method to show the gain
The test results are 53 hp more then the specs for my car . The stock 964 hp specs are 250 correct?
I got 303 on the dyno with about 25+ pulls . That is 53 hp right?
Like i said before I just am happy with a new mod that i have done and what'd to share it with the board.
John made no claims , I did .
As for the dyno test;
I have to disagree with the thought that running my car with the stock stuff, then running it with the MAF would result no good data.
When I run my car with the stock stuff it does in fact become the "blank" And running it with the MAF then it become the "sample". on the same instrument .That data is VALID, I spend a little time in the lab myself .
That test would show a gain , would the gain be the same for every car? NO
But it is a valid method to show the gain
Last edited by deoxford; 12-25-2007 at 02:39 PM.
12-22-2007, 08:25 PM
#152
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I think when a company comes on a board advertising a new product they should expect to be asked for some verifiable evidence that the modification works as advertised. In this case I believe it was a customer who set the expectation for a 50HP gain whereas the manufacturer didn't make any particular claim other than performance would be better.
So far the test results for this mod have been underwhelming - no noticable improvement over basically stock engine. Hopefully we'll see some better results in the weeks to come.
If someone has a legitimate performance upgrade for the 964 they are not going to stop offering it because of some harsh criticism on a bulletin board.
So far the test results for this mod have been underwhelming - no noticable improvement over basically stock engine. Hopefully we'll see some better results in the weeks to come.
If someone has a legitimate performance upgrade for the 964 they are not going to stop offering it because of some harsh criticism on a bulletin board.
it is all about the tone, let's just keep it civil. at the end of the day if you don't think the investment is worth it, vote with your Porsche dollars and don't buy it. but we've got a few keyboard jockey types who like to Monday morning quarterback things and throw some insults in for good measure.
12-22-2007, 08:55 PM
#153
g****,
The test results are 53 hp more then the specs for my car . The stock 964 hp specs are 250 correct?
I got 303 on the dyno with about 25+ pulls . That is 53 hp right?
Like i said before I just am happy with a new mod that i have done and what'd to share it with the board.
John made no claims , I did .
As for the dyno test;
I have to disagree with the thought that running my car with the stock stuff, then running it with the MAF would result no good data.
When I run my car with the stock stuff it does in fact become the "blank" And running it with the MAF then it become the "sample". on the same instrument .That data is VALID, I spend a little time in the lab myself .
That test would show a gain , would the gain be the same for every car? NO
But it is a valid method to show the gain
The test results are 53 hp more then the specs for my car . The stock 964 hp specs are 250 correct?
I got 303 on the dyno with about 25+ pulls . That is 53 hp right?
Like i said before I just am happy with a new mod that i have done and what'd to share it with the board.
John made no claims , I did .
As for the dyno test;
I have to disagree with the thought that running my car with the stock stuff, then running it with the MAF would result no good data.
When I run my car with the stock stuff it does in fact become the "blank" And running it with the MAF then it become the "sample". on the same instrument .That data is VALID, I spend a little time in the lab myself .
That test would show a gain , would the gain be the same for every car? NO
But it is a valid method to show the gain
Greg
12-22-2007, 09:37 PM
#154
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Hey Guys - if power/torque were related to the sound this thing lets the engine make... holy smokes!!!! I don't think I can run Laguna Seca with this thing installed!! It's amazing how much intake sound the Air Flow Meter and cut open airbox blocks out. 
...more to come 
...more to come
12-23-2007, 01:43 AM
#155
No hostility at all here. I love all you guys.
Derek,
Spec is 247 hp. So you're claiming 56hp.
Is 303 hp the result of 1 of 25+ pulls or is that an average?
Seems to me that the only true test is to test the stock setup on Derek's car - Stock exhaust, with stock chip, stock AFM, stock intake. Then increment up with whatever combination of exhaust, chip (timing map adjust), MAF/chip (Timing and fuel map adjust) you can come up with. Multiple runs with each setup. This will be expensive and take time.
My bet is that when you have a cat bypass and exhaust bypass (either kind), there is a statistically insignificant difference between a timing push vs. fuel map/timing push assuming stock injectors as has been seen before. That's the test to perform.
Happy Holidays to all.
12-23-2007, 11:12 PM
#158
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Thought your car was already fitted with a Promax MAF/chip tuned by Geoff.
https://rennlist.com/forums/diy-964-1989-1994-911/351619-installing-a-promax-maf-and-chip.html
If correct, what would move you to John's product?
12-24-2007, 11:59 AM
#160
"My bet is that when you have a cat bypass and exhaust bypass (either kind), there is a statistically insignificant difference between a timing push vs. fuel map/timing push assuming stock injectors as has been seen before."
That's it!
The key to remember is that three variables exist; i.e. the MAF meter,
the fuel map changes, and "pushed" timing maps. Without contolling for
each of these variables, the true effect of each variable can't really be
determined. The MAF mod mostly likely has all three variables changed.
As mentioned before, the variable which mostly likely produces the greatest
change, if there truely is a change, will be the "pushed" timing maps.
Given that's the case, the MAF mod car will run higher octane fuel to
avoid detonation, i.e. prevent the knock sensors from retarding the
timing thus reducing the torque. The higher octane adds another variable,
too.
That's it!
The key to remember is that three variables exist; i.e. the MAF meter,
the fuel map changes, and "pushed" timing maps. Without contolling for
each of these variables, the true effect of each variable can't really be
determined. The MAF mod mostly likely has all three variables changed.
As mentioned before, the variable which mostly likely produces the greatest
change, if there truely is a change, will be the "pushed" timing maps.
Given that's the case, the MAF mod car will run higher octane fuel to
avoid detonation, i.e. prevent the knock sensors from retarding the
timing thus reducing the torque. The higher octane adds another variable,
too.
12-24-2007, 12:22 PM
#161
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-------------Idle-----------Allowable--------Loaded on Dyno------------Allowable
HC (ppm)--000--------------123-------------------000----------------------128
CO (%)----0.00--------------0.69------------------0.01---------------------0.71
NO (ppm)--298--------------878-------------------602----------------------970
CO+CO2---15.1-------------6.0 min--------------15.0----------------------6.0 min
Cat bypass or MAF are "off road only" modifications under EPA and state regulations. Looking at the NO numbers, there is not much "push" available in timing before the limit is exceeded. I get knock sensor activity on hot days on pump gas. Any timing "push" would probably hurt my acceleration unless I gas up at the airport 100 octane pump ($6.00 per gallon last time I looked).
12-25-2007, 11:37 AM
#162
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Springer3
$6 per gallon, is that all
Here in the uk on Christmas eve I paid £5.08 per gallon
Say, $2 to £1 that makes $10.16 per gallon (I know uk and us gallons differ, but never the less that is ******* expensive!).
Have a good one and be grateful your government doesn't stiff you about 75%+ tax on petrol
$6 per gallon, is that all
Here in the uk on Christmas eve I paid £5.08 per gallon
Say, $2 to £1 that makes $10.16 per gallon (I know uk and us gallons differ, but never the less that is ******* expensive!).
Have a good one and be grateful your government doesn't stiff you about 75%+ tax on petrol
Last edited by madmoog; 12-25-2007 at 11:37 AM. Reason: spelling!
12-25-2007, 02:02 PM
#163
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93 octane premium pump gas is only $3.15/gallon, and 87 octane regular is still below $3 in Atlanta.
We in the US still have a very sweet deal. I don't think many of us appreciate it as much as we should.
Merry Christmas
We in the US still have a very sweet deal. I don't think many of us appreciate it as much as we should.
Merry Christmas
12-26-2007, 04:41 PM
#164
-------------------Static, no dyno-------------------
---------------------2433 rpm-------883 rpm-------
-------------------Measured--------Measured-------Spec (Texas)
HC (ppm)----------- 4 ----------- 5----------------220
CO%---------------- 0 ----------- 0.02-------------1.20
CO2%--------------- 6.9 ---------- 6.6----------------n/a
O2%---------------- 10.4---------- 10.9---------------n/a
NOx (ppm)-----------0---------------0------------------n/a
Dilution %------------6.9------------6.6----------------->6.0
12-27-2007, 02:21 AM
#165
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Interesting difference between our identical cars (I am also stock except for the primary bypass). Your NOX numbers are not correct - I don't think you can have zero. We are essentially the same for CO - the really bad stuff.