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New 911 product pre-announcement.

Hi Folks,

I've been working hard in the last few months on a new product for 84-94 911's, a bolt on MAF replacement system to do away with the old style vane air flow meters. Although there are some similar systems already out there I think my system is the best in terms of quality Vs cost.
I have a little more development work and testing to do and should be taking orders in the near future, here is my website:

www.gekkatec.com

I'll be adding updates on the website as time goes by and as I approach completion so please check back from time to time. I don't have actual photos of the unit as yet but I do have 3D cad models which are viewable with the basic adobe pdf reader.

Thanks and if anyone has any questions please don't hesitate to ask!

Chris

P.S. I'll be relying solely on word of mouth for my "advertising" so please tell any of your 911 friends who might be interested!
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Old 01-11-2009, 11:06 PM
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Sounds interesting. Keep us posted...

ianc
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Old 01-11-2009, 11:15 PM
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Quote:
Originally Posted by ianc View Post
Sounds interesting. Keep us posted...

ianc
Will do, thanks!
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Old 01-12-2009, 08:45 AM
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Garage
Do you have a price point sorted out yet or are you still working on pricing?
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Old 01-12-2009, 10:08 AM
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Quote:
Originally Posted by vanwyk4257 View Post
Do you have a price point sorted out yet or are you still working on pricing?

Pricing is on the website for my first product, I will also be giving group discounts although I don't have an actual % figure for the price off yet, I guess it will depend on how many.

Thanks
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Old 01-12-2009, 10:25 AM
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$1300 ? how does this effect HP? Any dyno results?

You may want to sell the product through Wayne. He seems to frown on those using his site to direct folks to their own direct sales.

Doug
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Old 01-12-2009, 11:25 AM
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interesting as I have customers ask about these all the time. Keep us updated
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Old 01-12-2009, 12:47 PM
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Great concept.

Couple of ideas to through in the pot.

How about adding a little tune-ability. The stock AFM can in effect be adjusted to make for a faster or slower amount of movement with changes in air flow.

Also, the stock AFM stalls at about 5200rpm. I am not sure if provision can be made at the unit to change this.

For ideas go to Split Second Timing, inc.. They have adapters that you can adjust slope and change the curve of the slope for achieving better Air Fuel ratios. (Not sure of the correct terminology).

Next, as you are going to already be sensing air pressure, how about also taking over the WOT switch function with your processor. You could trigger the acceleration fuel map anytime there is any level of modest acceleration (loss of vacuum in the manifold) instead of the driver having to floor the accelerator to trigger the WOT or acceleration map.

I am thinking a couple of tunning pot's on the unit.

Good luck.
Old 01-12-2009, 02:23 PM
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Here is the link to the Split Second Timing:

www.splitsec.com

They have universal MAF conversion kits and lots of other goodies. I used a custom controller they built for me to drive a frequency valve on my 91 C2 Turbo years ago so I could tune my Air Fuel ratios at all rpm and load/boost ranges and access more fuel at the top end where CIS turbos often run out of fuel.
Old 01-12-2009, 02:34 PM
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Quote:
Originally Posted by 911st View Post
Great concept.

Couple of ideas to through in the pot.

How about adding a little tune-ability. The stock AFM can in effect be adjusted to make for a faster or slower amount of movement with changes in air flow.

Also, the stock AFM stalls at about 5200rpm. I am not sure if provision can be made at the unit to change this.

For ideas go to Split Second Timing, inc.. They have adapters that you can adjust slope and change the curve of the slope for achieving better Air Fuel ratios. (Not sure of the correct terminology).

Next, as you are going to already be sensing air pressure, how about also taking over the WOT switch function with your processor. You could trigger the acceleration fuel map anytime there is any level of modest acceleration (loss of vacuum in the manifold) instead of the driver having to floor the accelerator to trigger the WOT or acceleration map.

I am thinking a couple of tunning pot's on the unit.

Good luck.
Hey, Thanks for the input, presently my design has the ability to be fine tuned, it basically has a DIP switch and a pot on it, if the DIP is off the unit gives stock voltages according to flow (this is how most users will use the unit, fit and forget, no tuning necessary), with the DIP ON the pot can be used to richen or weaken the mixture 5%. This adjusts the mixture over the entire RPM range, I decided to put in for a couple of reasons, one is folks who like to tinker and want to try and squeeze a few more horses out of their car, the other is perhaps people who need that last little bit of adjustment to squeeze through smog.

I could add the ability to do more adjustments on the flow output voltage Vs actual flow input for advanced tuning, however the issue I have with units that have basic adjustment capability is that they are quite crude, they have control points at a few points in the rpm range which you dial up and down. This is not very good mapping and will lead to areas that run too rich and others that run just right.
The only way to really adjust the mixture in this way is to have a unit that is fully programmable rather than a few points. I will look into making an add on that can piggy back into my MAF/VFM computer to give it the ability to modify the flow response. It can be done but the question is is there a market for it?

My pressure compensation works on the actual atmospheric pressure relative to a vacuum, it is not a MAP sensor so it is not aware of the pressure behind the butterfly valve. So I doubt it would be possible to trigger the WOT map on the DME.

I am still testing my unit presently, so I will know more about what happens after 5200rpm when I've completed more testing, it may be that the Bosch motronic unit won't register flow voltages after its reached a certain threshold, or it may allow the DME to meter fuel more precisely after this rpm is reached. My MAF setup right now can flow more air than the stock unit, IE the sensor will not be pegged even with a high output 911 engine. I will do some calculations on the theoretical horsepower limit on this unit.

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Old 01-12-2009, 04:57 PM
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Quote:
Originally Posted by DW SD View Post
$1300 ? how does this effect HP? Any dyno results?

You may want to sell the product through Wayne. He seems to frown on those using his site to direct folks to their own direct sales.

Doug
Yeah the price is $1300, originally I wanted to bring this to market at a lower cost, but after doing a parts breakdown cost total and the time to assemble/test etc I had to put the price up.
I wanted to make it available as a better option than the stock Bosch unit which is almost the same price, however my unit will be much superior to the old VFM design.
HP figures will really vary on many things, state of engine tune, condition, leakdown etc etc. So for me to throw out numbers I feel would not be honest, I can say for certain that the unit will flow more than stock and from the experience of other posts on this forum this leads to more power for such MAF units.

I don't want to tread on anyone toes posting on the forum, I know that Pelican does not sell a competing product and that from my reading various posts on the forum a number of folks have expressed a great deal of interest in a MAF product such as mine.
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Old 01-12-2009, 05:07 PM
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Just seems like so many people have offered a MAF conversions, is MAF really the way to go? I know it's good for emissions but for all out power isn't MAP the way to go? I'm trying to get a company that makes well proven MAP piggybacks to set one up for my car, fully tunable and quite affordable.
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Old 01-12-2009, 05:13 PM
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Quote:
Originally Posted by spence88mph View Post
Just seems like so many people have offered a MAF conversions, is MAF really the way to go? I know it's good for emissions but for all out power isn't MAP the way to go? I'm trying to get a company that makes well proven MAP piggybacks to set one up for my car, fully tunable and quite affordable.
Actually, functionally they do basically the same thing, the MAF measures the mass of air going into the engine so the ECU can meter enough fuel for it, the MAP together with an RPM sensor measures the pressure at the engine side of the throttle, knowing the RPM as well it can calculate the quantity of air going into the engine.

I tend to think MAF is more precise than MAP, as far as power is concerned you could argue that not having a MAF sensor in the intake removes restriction, but the modern MAF's are small and other areas of the engine are more restrictive, so its really a non issue.
All modern cars use MAF so its a well tested system.
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Old 01-14-2009, 11:18 AM
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Update on progress

For those folks who were interested in updates on how this is going, here are a couple of photos of my prototype system, obviously the final version will be tidier and will include mounting brackets etc.
I'll be posting a video or two of it running on the car today or tomorrow, so watch this space!


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Old 01-25-2009, 12:32 PM
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Will this pass a Calif. smog inspection? Looks like an interesting product!
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Old 01-25-2009, 12:45 PM
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Success!!



Fitted the system to my 911 today, had a problem with a bad MAF sensor so switched out for a spare and it worked great!

If you go to youtube you can watch it in HD by clicking under the video to the right.

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Last edited by Bart_dood; 01-25-2009 at 03:57 PM..
Old 01-25-2009, 03:32 PM
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Congrats.

I like the pot that increases and decreases the sensor curve up and down.

Would be nice to have one that keeps the idle point fixed and raises the high and lowers the high rpm point (slope of the curve).

Those two together would approximate the adjustably of the factory unit.

The cream would be one other to effect the temperature output but only above 5000rpm. This would give us a little control over total ignition advance up top which can have a solid effect HP.

I like the custom tube. How about just using the 993 unit, it comes with the tube and sensor already for under $300?

Would be easy to build a test bench using an variable electric motor hooked to a Vortec supercharger.

The MAF could be put in series with a new factory calibrated AFM to ensure quality.

Jut some thoughts.
Old 01-25-2009, 05:03 PM
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Driving impressions update

So I've been working some more on the system over the last couple of nights, some fine tuning was required for actual driving plus I finished off the code for the idle mixture adjustment (electronic equivalent of the hex screw on the stock air flow meter).

The system runs very nice, the first thing I noticed is how smooth it was, at any point in the rpm range the car has no hiccups or hesitation, I had it down to less than 1500rpm in fifth gear and it cruises along smooth, press on the gas and it accelerates fine.

It seems to pull harder at higher rpms, its a seat of the pant figure but I'd say around 8-10hp, also the transition through 4000rpms is more progressive, it used to feel like you'd hit a hump of torque/horsepower at around 4000rpms like it was coming on the cam, now it pulls more evenly, perhaps the torque curve just under 4k rpms has filled up a little making the power curve more progressive.

I'd say throttle response is slightly better, but only slightly, although my system is very fast I think it is faster than the motronic so the stock injection system is now the throttle response limited factor.

I have a little more tuning to do, my code is finished and I'm just finalizing some numbers, I'll be working towards my production builds etc now for release.

Thanks!

Oh and for the guy asking about smog, this product should give superior emissions and fuel economy than the stock system (so if they check the tail pipe it will pass no trouble), however it might not pass visual smog check if your tech has a very keen eye and notices its not stock. However a lot of folks might just think its a stock system. A nice feature of this system is how quickly it can be switched out, probably around 15-20mins for an experience person.
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Last edited by Bart_dood; 01-28-2009 at 09:43 PM..
Old 01-28-2009, 09:40 PM
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Quote:
Originally Posted by 911st View Post
Congrats.

I like the pot that increases and decreases the sensor curve up and down.

Would be nice to have one that keeps the idle point fixed and raises the high and lowers the high rpm point (slope of the curve).

Those two together would approximate the adjustably of the factory unit.

The cream would be one other to effect the temperature output but only above 5000rpm. This would give us a little control over total ignition advance up top which can have a solid effect HP.

I like the custom tube. How about just using the 993 unit, it comes with the tube and sensor already for under $300?

Would be easy to build a test bench using an variable electric motor hooked to a Vortec supercharger.

The MAF could be put in series with a new factory calibrated AFM to ensure quality.

Jut some thoughts.
Thanks! Its been a lot of work but I'm 95% complete now.
At the moment the system only has an adjustment for the idle mixture, this is to replace the hex adjustment on the stock air flow meter, although I am still deciding if I will include the capability to tweak the air/fuel mixture across the flow range via USB programming. I have to weigh the pros and cons as far as hardware design etc.
There is no way to really mess with the motronic temperature signal, my system does not interfere with this signal but just replaces the stock thermal sensor built into the aluminum housing with an exact equivalent.
The microprocessor uses the MAF temperature signal for its computations for temperature correction.
The reason I went with the hot wire MAF sensor that I'm using is because its a very robust tried and tested unit, its way more responsive than the stock flapper AFM.
As far as the bosch units used on the newer porsche's and other cars they seem to suffer from reliability problems, I have read a lot of problems from burned out MAF's of this type. As there is no performance advantage to the bosch unit over the one I chose I saw little reason to use something with a worse reputation for reliability.
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Old 01-28-2009, 09:53 PM
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Good looking and a good effort.

Good news on the idle voltage adjustment.

The factory unit also has the ability to adjust for the rate of change relative to changes in air flows. May not be as important with a digital system like yours as long as the output is not going to vary unit to unit or over time like when a springs elasticity changes. If it is subject to such issues an adjustment that locks the idle voltage but changes all points to red line a percentage of the adjustment (increasing or decreasing the slope of the line) would more match the adjustably of the stock AFM. Again, being digital this might not be as necessary.

As to the temp input, you could run this through your processor and then allow that at the air flow rates that equal WOT load from 5000rpm to red line offer an ability to clamp the signal, this would allow the system to positively effect the ignition curve where it may produce solid effect.

Best of luck.
Old 01-29-2009, 08:58 AM
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