MAF confusion....how do I choose??
03-03-2002, 08:09 AM
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MAF confusion....how do I choose??
I know that MAF conversions is a heavily covered topic on the board, but I'm still having a hard time sorting through all of the options out there for my '86 951. My goal at this point is to get a system that will improve throttle response, add ~some~ hp, and work with my stock turbo.
This is a street/light track duty car so low RPM driveability is important. At this point, I'm not looking to make massive hp...yet. ;-) Also, I don't want to spend hours tweeking the A/F ratio to get the car to run properly at idle through full throttle.
Here's what I have found by searching the archives:
Lindsey Racing
<a href="http://www.lindseyracing.com" target="_blank">www.lindseyracing.com</a>
They claim to have a unique design that incorporates an air temperature sensor. Apparently many other designs use a signal from the coolant temp. Their MAC II Mass Air Controller looks pretty simple (only 2 *****) but maybe that is a good thing!
Speed Force Racing
<a href="http://www.speedforceracing.com" target="_blank">www.speedforceracing.com</a>
Their claim to fame is that the "sensor is as far away from the turbo as possible." I can see from the website pics that indeed the sensor is located very close to the air filter. This one uses the ARM1 air/fuel ratio meter and the ARC2 fuel controller.
Huntley Racing
<a href="http://www.huntleyracing.com" target="_blank">www.huntleyracing.com</a>
Set-up looks similar to the one from Speed Force Racing. The inlet tube appears to have good adjustability to get the air filter to fit properly behind the headlight. This one also uses the ARM1 air/fuel ratio meter and the ARC2 fuel controller. Does this option require new DME/KLR chips? The ARC2 controls the A/F ratio but nothing else, right?
Powerhaus
<a href="http://www.powerhaus.com" target="_blank">www.powerhaus.com</a>
Not too much detail from this supplier on their website, but it does make reference to a "pair of custom computer chips" being included in the kit."
Autothority
<a href="http://www.autothority.com" target="_blank">www.autothority.com</a>
I have seen some favorable comments about this option from several board members. They have described this as a bolt-on, plug-in and go set-up with a good price too. Apparently it does not have the adjustability as some other options, but again, that may be a good thing unless you have a dyno in your garage! However, I just checked their website and they list the price at $1,999 which does not include any reworked air intake ducting!
Can you guys help me sort out the options? I know that there will be some strong opinions out there...let's hear them!
This is a street/light track duty car so low RPM driveability is important. At this point, I'm not looking to make massive hp...yet. ;-) Also, I don't want to spend hours tweeking the A/F ratio to get the car to run properly at idle through full throttle.
Here's what I have found by searching the archives:
Lindsey Racing
<a href="http://www.lindseyracing.com" target="_blank">www.lindseyracing.com</a>
They claim to have a unique design that incorporates an air temperature sensor. Apparently many other designs use a signal from the coolant temp. Their MAC II Mass Air Controller looks pretty simple (only 2 *****) but maybe that is a good thing!
Speed Force Racing
<a href="http://www.speedforceracing.com" target="_blank">www.speedforceracing.com</a>
Their claim to fame is that the "sensor is as far away from the turbo as possible." I can see from the website pics that indeed the sensor is located very close to the air filter. This one uses the ARM1 air/fuel ratio meter and the ARC2 fuel controller.
Huntley Racing
<a href="http://www.huntleyracing.com" target="_blank">www.huntleyracing.com</a>
Set-up looks similar to the one from Speed Force Racing. The inlet tube appears to have good adjustability to get the air filter to fit properly behind the headlight. This one also uses the ARM1 air/fuel ratio meter and the ARC2 fuel controller. Does this option require new DME/KLR chips? The ARC2 controls the A/F ratio but nothing else, right?
Powerhaus
<a href="http://www.powerhaus.com" target="_blank">www.powerhaus.com</a>
Not too much detail from this supplier on their website, but it does make reference to a "pair of custom computer chips" being included in the kit."
Autothority
<a href="http://www.autothority.com" target="_blank">www.autothority.com</a>
I have seen some favorable comments about this option from several board members. They have described this as a bolt-on, plug-in and go set-up with a good price too. Apparently it does not have the adjustability as some other options, but again, that may be a good thing unless you have a dyno in your garage! However, I just checked their website and they list the price at $1,999 which does not include any reworked air intake ducting!
Can you guys help me sort out the options? I know that there will be some strong opinions out there...let's hear them!
03-03-2002, 10:49 AM
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I have a thought (suprise), forgo the MAF and spend the same $ on a SDS standalone engine management system and realize every benefit of a MAF with none of the drawbacks (tunability with car as is, tunability with car as it becomes). Forget trying to "fake out" the DME and layers of corrective electronics. If you hold on a bit I'll really tell you how I feel! 
03-03-2002, 12:52 PM
#4
Nordschleife Master
I have a Huntley Stage 3 MAF system. The install procedure was very easy to do and straight forward. The power increase was definitely something you can feel. Overall power band was improved, the car felt a lot more snapper, boost came on about 500-700 rpms sooner, and it made an awesome sucking sound when ever you got on it. However the ARC2 can be a pain to tune at times, especially when its hot or cold seems like I’am always adjusting the low and mid to get the idle right. Now only if those ***** had potentiometers with a greater resistance range then I could get it just right.
The SFR one is very similar to the Huntley unit. I would recommend this unit or the Huntley unit for your next upgrade. I really don't like the Lindsey setup, doesn't seem to have the tuneablity of the other systems. The Autothority system is a put on and forget type MAF system, so there is not allot of tuning involved. The Power Haus MAF is a modified Authority system with tuneablity features like the ARC2.
If you plan on making even more upgrades such as a turbo or exhaust stay away from the Powerhaus, and Lindsey units. They just don’t have the ability to be tuned proparlywhen future upgrades are added.
Good Luck
The SFR one is very similar to the Huntley unit. I would recommend this unit or the Huntley unit for your next upgrade. I really don't like the Lindsey setup, doesn't seem to have the tuneablity of the other systems. The Autothority system is a put on and forget type MAF system, so there is not allot of tuning involved. The Power Haus MAF is a modified Authority system with tuneablity features like the ARC2.
If you plan on making even more upgrades such as a turbo or exhaust stay away from the Powerhaus, and Lindsey units. They just don’t have the ability to be tuned proparlywhen future upgrades are added.
Good Luck
03-03-2002, 02:10 PM
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Just a couple clarification items - AFAIK, all MAF kits will come with new DME and KLR chips... also, the APE system street price is closer to $1700.
Good Luck!
Good Luck!
03-03-2002, 02:55 PM
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[quote]Originally posted by Russ Murphy:
<strong>I have a thought (suprise), forgo the MAF and spend the same $ on a SDS standalone engine management system and realize every benefit of a MAF with none of the drawbacks (tunability with car as is, tunability with car as it becomes). Forget trying to "fake out" the DME and layers of corrective electronics. If you hold on a bit I'll really tell you how I feel! </strong><hr></blockquote>
If you're not willing to spend the time to tune a standalone engine management system, get a MAF. If you ARE willing to invest in the initial setup time, standalone EFI is very rewarding. My daily driver SDS 951 runs awesome in ANY temperature range. Fires right up everytime in -30C or 30C temperatures without tweaking!
Here's a few videos of my car in action :
<a href="http://www.virgeweb.com/rage2/944t/2002-01%20951%20dyno.wmv" target="_blank">dyno run</a>
<a href="http://www.virgeweb.com/rage2/944t/2002-01%20Calgary%20Local%20Car%20Meet%20Video.wmv" target="_blank">First 103 Octane Test</a>
<a href="http://www.virgeweb.com/rage2/944t/2002-03%20951%20immature%20fun.wmv" target="_blank">91 Octane Hill climb</a>
On Road Dyno Results :
308rwhp - 91 octane, 12psi boost
372rwhp - 103 octane, 20psi boost (run aborted at 4800rpm, will do full run when weather permits)
Dynojet Dyno Results :
338rwhp, 404ft-lbs rwTQ - 103 octane, 14-18psi boost (engine can't make boost at high rpms on dynojet, not enough of a load)
<strong>I have a thought (suprise), forgo the MAF and spend the same $ on a SDS standalone engine management system and realize every benefit of a MAF with none of the drawbacks (tunability with car as is, tunability with car as it becomes). Forget trying to "fake out" the DME and layers of corrective electronics. If you hold on a bit I'll really tell you how I feel!
</strong><hr></blockquote>If you're not willing to spend the time to tune a standalone engine management system, get a MAF. If you ARE willing to invest in the initial setup time, standalone EFI is very rewarding. My daily driver SDS 951 runs awesome in ANY temperature range. Fires right up everytime in -30C or 30C temperatures without tweaking!
Here's a few videos of my car in action :
<a href="http://www.virgeweb.com/rage2/944t/2002-01%20951%20dyno.wmv" target="_blank">dyno run</a>
<a href="http://www.virgeweb.com/rage2/944t/2002-01%20Calgary%20Local%20Car%20Meet%20Video.wmv" target="_blank">First 103 Octane Test</a>
<a href="http://www.virgeweb.com/rage2/944t/2002-03%20951%20immature%20fun.wmv" target="_blank">91 Octane Hill climb</a>
On Road Dyno Results :
308rwhp - 91 octane, 12psi boost
372rwhp - 103 octane, 20psi boost (run aborted at 4800rpm, will do full run when weather permits)
Dynojet Dyno Results :
338rwhp, 404ft-lbs rwTQ - 103 octane, 14-18psi boost (engine can't make boost at high rpms on dynojet, not enough of a load)
03-03-2002, 08:58 PM
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I installed the Autothority MAF because of it's plug and play simplicity and the fact that I've had good experience in the past with Autothority. The results are impressive. Power is great, the car pulls hard and turbo lag diminished a bit. I highly recommend it especially since there is no tuning involved. I paid $1625.00 delivered from GPR Parts.com
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03-03-2002, 09:12 PM
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lou951,
Did your Autothority set-up @ $1625 delivered come with a new "J-boot" so that the air filter is now located in front of the coolant reservoir? Several pictures at the website do not show this as part of the kit.
Although I suppose it would function in the stock airbox location, one of the benefits of the MAF is to free up space behind the intercooler for larger pipes. Also, I would expect the air temperature to be cooler near the fender than directly in front of the block!
Thanks for the clarification,
-MDW
Did your Autothority set-up @ $1625 delivered come with a new "J-boot" so that the air filter is now located in front of the coolant reservoir? Several pictures at the website do not show this as part of the kit.
Although I suppose it would function in the stock airbox location, one of the benefits of the MAF is to free up space behind the intercooler for larger pipes. Also, I would expect the air temperature to be cooler near the fender than directly in front of the block!
Thanks for the clarification,
-MDW
03-03-2002, 10:10 PM
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Our mass-flow set-up uses the existing airflow meter temp wire to allow the new mass-air sensor temp reading to be interpreted by the ARC2 and then the DME.A seperate temp sender justs adds clutter under the hood and isnt neccessary.B
Besides moving the sensor far away from the turbo as possible, we also have some other options that none of these other companies offer.For example, 6061 aluminum or 304 stainless tubing with a satin, powdercoated or polished finished. We also offer intercooler pipes and blow-off valve upgrades along with your choice of colored hoses (RED, Blue or Black).
Most people never tune thier cars on the dyno with the ARC2 set-ups so tuning issues are to be expected. Anytime you mess with the induction or exhaust systems, you need to properly tune your car for the maximum performace possible.It is not uncommon for people to extract 50 or more horsepower (as well as drivability they thought was lost) with some proper dyno tuning.
Tim
85 951
<a href="http://www.speedforceracing.com" target="_blank">http://www.speedforceracing.com</a>
Besides moving the sensor far away from the turbo as possible, we also have some other options that none of these other companies offer.For example, 6061 aluminum or 304 stainless tubing with a satin, powdercoated or polished finished. We also offer intercooler pipes and blow-off valve upgrades along with your choice of colored hoses (RED, Blue or Black).
Most people never tune thier cars on the dyno with the ARC2 set-ups so tuning issues are to be expected. Anytime you mess with the induction or exhaust systems, you need to properly tune your car for the maximum performace possible.It is not uncommon for people to extract 50 or more horsepower (as well as drivability they thought was lost) with some proper dyno tuning.
Tim
85 951
<a href="http://www.speedforceracing.com" target="_blank">http://www.speedforceracing.com</a>
03-03-2002, 10:24 PM
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[quote]Originally posted by TurboTim:
<strong>Anytime you mess with the induction or exhaust systems, you need to properly tune your car for the maximum performace possible.It is not uncommon for people to extract 50 or more horsepower (as well as drivability they thought was lost) with some proper dyno tuning.</strong><hr></blockquote>
Well said, and after spending nearly $2k or more on this sort of stuff... $150 of dyno time should seem quite worthwhile. Whichever system you choose, find a qualified dyno shortly thereafter.
Skip
<strong>Anytime you mess with the induction or exhaust systems, you need to properly tune your car for the maximum performace possible.It is not uncommon for people to extract 50 or more horsepower (as well as drivability they thought was lost) with some proper dyno tuning.</strong><hr></blockquote>
Well said, and after spending nearly $2k or more on this sort of stuff... $150 of dyno time should seem quite worthwhile. Whichever system you choose, find a qualified dyno shortly thereafter.
Skip
03-04-2002, 02:05 AM
#12
Race Car
tt9714,
Me thinks Rage hit it on the head...!
There are some who want hands off (chips), some hands on (MAF), or total control (stand alone), over the systems tuning...
You need to figure out which YOU want....!
Me thinks Rage hit it on the head...!
There are some who want hands off (chips), some hands on (MAF), or total control (stand alone), over the systems tuning...
You need to figure out which YOU want....!
03-04-2002, 02:22 AM
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hey Luke i just got an email back from pro flo about a maf conversion for the NA cars. here is the reply from James Gonzales from pro flow
Yes we make mass air flow meters for the 944 units. We have the
transfer functions listed on the web site. Also if you are doing the
conversion we can supply you with a unit, just tell me how much air you
are going to be putting thru the unit, or how much hp you plan on
running.
Yes we make mass air flow meters for the 944 units. We have the
transfer functions listed on the web site. Also if you are doing the
conversion we can supply you with a unit, just tell me how much air you
are going to be putting thru the unit, or how much hp you plan on
running.
03-04-2002, 07:53 AM
#14
Nordschleife Master
mine is 80 mm. I didn't give him any info. Just told him it was an 86' 951. It sure looks like it will work. I will be spending at least an hour of dyno time tuning it. I'm pretty comfident that it can do the job just as well as any other. I just dont understand why everybody else avoids it like it's the plague??? I think that's silly, to not consider a product just because it is cheaper? <img src="confused.gif" border="0">
03-04-2002, 01:06 PM
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One more vender chime in. Adjustable MAF kits are the ONLY proper way to do this conversion. The chip-only systems are far to relient on the car being EXACTLY as the chip designers car he used to make the chips. If your car is different it will be off on the mixtures. Our kit is the only one with a Porsche specific proprietary ARC2. You can not get this anywhere else. Non-HR ARC2 units will have a very rich spot in the middle of the RPM range followed by a lean out on the top end. This in not what you want with a 944 turbo fuel curve. We have sold more MAF kits than any other supplier world wide and continue to do so.