Finally Turbo Power for my Carrera!

[Dynamohum]

Originally Posted by spence88mph

I have completed the turbo conversion and can speak from experience unlike your speculation above. I can tell you that many turbos blow oil through the intake, not good for an AFM, I can tell you the AFM's threads will thread very easily as it's made of crappy cast alloy so getting a good strong seal to it is a PITA unless you helicoil it which I ended up doing (no biggie).

Unless you modify the exit with a retaining flange there's a good chance you will blow off the elbow to the throttle body. This has happened to me and friends cars many times. All these issues would not be a factor with suck through, that is why I am saying it would likely be a better set up and it's not new I've seen it on a few cars with good results.

The only reason I'm not converting to suck through as I did contemplate it, is I'm converting to MAP in the next couple of weeks, as soon as I get a chance to install the sensor. I'll also be able to tell you all how soon the flapper maxes out which I'm predicting would be very early in the rev range like 2500rpm but it's speculation. You could test this by connecting a volt meter to the AFM signal and see where and when it hits 5.0V.



Not correct, it measures flow not pressure/volume.

Spence, I was making a reference to the volume of the connecting hose.



Oh ok, that's why Porsche used it in the 951 and hmmm wonder if they chose blow through or suck through, do some research....

Spence, Though I spend a tremendous amount of time researching and sifting through information I had not yet come across this, thanks, I will check it out.


And your findings here are based on?
Spence, from forums, online research, Performance Handbook by Bruce Anderson.


Sick of the bench racers!!!

Spence, Thank You for your input. You raised good points on the Pros and Cons of both layouts.

Knowledge and Real World Experience is what we are after, and very helpful to those of us doing this conversion.

This forum is a great place to ask questions share knowledge, learn from each others personal experience and present new ideas when it is done in a constructive manner.
Please my questions and comments are intended in this spirit.

[Dynamohum]

Originally Posted by spence88mph

I have completed the turbo conversion and can speak from experience unlike your speculation above. I can tell you that many turbos blow oil through the intake, not good for an AFM, I can tell you the AFM's threads will thread very easily as it's made of crappy cast alloy so getting a good strong seal to it is a PITA unless you helicoil it which I ended up doing (no biggie).

Unless you modify the exit with a retaining flange there's a good chance you will blow off the elbow to the throttle body. This has happened to me and friends cars many times. All these issues would not be a factor with suck through, that is why I am saying it would likely be a better set up and it's not new I've seen it on a few cars with good results.

The only reason I'm not converting to suck through as I did contemplate it, is I'm converting to MAP in the next couple of weeks, as soon as I get a chance to install the sensor. I'll also be able to tell you all how soon the flapper maxes out which I'm predicting would be very early in the rev range like 2500rpm but it's speculation. You could test this by connecting a volt meter to the AFM signal and see where and when it hits 5.0V.



Not correct, it measures flow not pressure/volume.

Spence, I was making a reference to the volume of the connecting hose.



Oh ok, that's why Porsche used it in the 951 and hmmm wonder if they chose blow through or suck through, do some research....

Spence, Though I spend a tremendous amount of time researching and sifting through information I had not yet come across this, thanks, I will check it out.


And your findings here are based on?
Spence, from forums, online research, Performance Handbook by Bruce Anderson.


Sick of the bench racers!!!

Spence, Thank You for your input. You raised good points on the Pros and Cons of both layouts.

Knowledge and Real World Experience is what we are after, and very helpful to those of us doing this conversion.

This forum is a great place to ask questions, share knowledge, learn from each others personal experience and present new ideas when it is done in a constructive manner.
Please my questions and comments are intended in this spirit.

[Dynamohum]

Sorry about the previous double post, there was a glitch while uploading.
I'm no Expert, I do however enjoy reading and learning. Here is some info on IC and the adjoining tube assemblies

Here is a link to some interesting reading on IC http://www.bellintercoolers.com/pages/techFAQ.html

Are there other factors of flow loss, in the intercooler assembly, rather than just the core?
Yes, entry into the intercooler inlet tank and the smoothness of the exit tank. The adjoining tube assemblies, their length, size and bend configurations are all part of the flow loss total.
< Return to Top

How/why is the flow loss significant?
The net result is the production of power. It is hugely important because the power required to drive the air thru the system must come from somewhere. Depending on whether the system is turbocharged or supercharged, will determine how much power is lost from the restriction.
< Return to Top

What factors affect the pressure or flow loss?
The internal flow area is the major controlling factor. Tube length is the second biggest consideration, as a tube twice as long as another will have nearly twice the drag at the same air velocity. Tube entry and turbulator density play small roles and can be considered insignificant. When configuring the orientation of the core in a given space, always position the core to offer the shortest length tube and the most number of tubes. Clearly, this optimizes the internal flow area.
< Return to Top

Are there any improvements that can be made to the system for improved efficiency?
Yes, several small factors influence the efficiency. A proper duct is probably the single most beneficial thing that can be done to an existing intercooler. Positioning in the main stream of ambient air is crucial. By comparison, a taped up intercooler with no ambient air flow will offer only about 20% efficiency.
< Return to Top

Is some intercooling better than no intercooling?
No. It depends on the design of the intercooler, and there are two factors involved; efficiency (how much heat is removed) and the flow restriction (lost pressure) created by the presence of the intercooler. Regardless of the efficiency, if too much pressure is lost, then the intercooler is either useless or can actually decrease performance.
< Return to Top

[wanabe911 owner]

They are going to clean up that intake, install a boost gauge, and check what spring is in the wastegate. I can say that on or off boost it drives great. Off boost is like it wasnt even modified. On boost it just picks up and hauls! Does make any strange noises, no knock or pinging, and Ben's exhaust is great! I will post some more details and pictures later in the week. I would also like to pursue installing a LM1 and a water/alcohol injection system.

[Dynamohum]

Originally Posted by wanabe911 owner

They are going to clean up that intake, install a boost gauge, and check what spring is in the wastegate. I can say that on or off boost it drives great. Off boost is like it wasnt even modified. On boost it just picks up and hauls! Does make any strange noises, no knock or pinging, and Ben's exhaust is great! I will post some more details and pictures later in the week. I would also like to pursue installing a LM1 and a water/alcohol injection system.

Looking forward to seeing more photos on your conversion and intake sys.

Good luck and all the best, Paul

[wanabe911 owner]

Here are some hopefully better pictures, and a redesigned intake.

[Dynamohum]

Information to consider when designing and comparing Draw VS Blow ducting configurations using the Motronic (barn door) AFM in a 3.2 turbo conversion

Excerpts From Garrett http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_tech103.html


· In determining pressure ratio, the absolute pressure at the compressor inlet (P2c) is often LESS than the ambient pressure, especially at high load. Why is this? Any restriction (caused by the air filter or restrictive ducting) will result in a “depression,” or pressure loss, upstream of the compressor that needs to be accounted for when determining pressure ratio. This depression can be 1 psig or more on some intake systems. In this case P1c on a standard day is:

With Mass Flow and Manifold Pressure, we are nearly ready to plot the data on the compressor map. The next step is to determine how much pressure loss exists between the compressor and the manifold. The best way to do this is to measure the pressure drop with a data acquisition system, but many times that is not practical.
Depending upon flow rate, charge air cooler characteristics, piping size, number/quality of the bends, throttle body restriction, etc., the plumbing pressure drop can be estimated. This can be 1 psi or less for a very well designed system. On certain restrictive OEM setups, especially those that have now higher-than-stock airflow levels, the pressure drop can be 4 psi or greater.

[Dynamohum]

Originally Posted by wanabe911 owner

Here are some hopefully better pictures, and a redesigned intake.

I'm assuming that this is still a temp set up until your IC is installed?

It looks more robust than the first set up, hopefully it holds together until your other modifications are done. If you end up installing a W/A injector upstream of the TB for better atomization consider upgrading your intake tubing at the same time. The way the charge pipe (turbo to intake) was welded and fabricated together looks restrictive to me.

Do yourself a favor, Take it apart and check the inside of that pipe and take some photos and let us know what you see. For the sake of your motor I hope they did a good job of cleaning up any debris from their welding?
Another thing: Look the black intake elbow in your 2nd photo and in your last photo; looks like they installed a 90 deg copper house plumbing elbow with silicon. Look inside the big intake elbow and make sure that there is no blobs of silicon waiting for your motor to ingest.

Please I don't want to offend by saying that their work looks questionable, I bring this up because I would not want to see you loose your motor over it.

Remember an Ounce of prevention is worth a pound of Cure!

You mentioned possible adding a W/A system, check this out
http://forums.pelicanparts.com/showthread.php?t=455080

Question: What wastegate spring / boost pressure are you running?

[mb911]

Originally Posted by Dynamohum

I'm assuming that this is still a temp set up until your IC is installed?

It looks more robust than the first set up, hopefully it holds together until your other modifications are done. If you end up installing a W/A injector upstream of the TB for better atomization consider upgrading your intake tubing at the same time. The way the charge pipe (turbo to intake) was welded and fabricated together looks restrictive to me.

Do yourself a favor, Take it apart and check the inside of that pipe and take some photos and let us know what you see. For the sake of your motor I hope they did a good job of cleaning up any debris from their welding?
Another thing: Look the black intake elbow in your 2nd photo and in your last photo; looks like they installed a 90 deg copper house plumbing elbow with silicon. Look inside the big intake elbow and make sure that there is no blobs of silicon waiting for your motor to ingest.

Please I don't want to offend by saying that their work looks questionable, I bring this up because I would not want to see you loose your motor over it.

Remember an Ounce of prevention is worth a pound of Cure!

You mentioned possible adding a W/A system, check this out
http://forums.pelicanparts.com/showthread.php?t=455080

Question: What wastegate spring / boost pressure are you running?

Sound advice never want to run any debri through so check it out. and if you have a good sample I could always make a nice setup out of aluminum or stainless if you like?

[wanabe911 owner]

Originally Posted by Dynamohum

I'm assuming that this is still a temp set up until your IC is installed?

It looks more robust than the first set up, hopefully it holds together until your other modifications are done. If you end up installing a W/A injector upstream of the TB for better atomization consider upgrading your intake tubing at the same time. The way the charge pipe (turbo to intake) was welded and fabricated together looks restrictive to me.

Do yourself a favor, Take it apart and check the inside of that pipe and take some photos and let us know what you see. For the sake of your motor I hope they did a good job of cleaning up any debris from their welding?
Another thing: Look the black intake elbow in your 2nd photo and in your last photo; looks like they installed a 90 deg copper house plumbing elbow with silicon. Look inside the big intake elbow and make sure that there is no blobs of silicon waiting for your motor to ingest.

Please I don't want to offend by saying that their work looks questionable, I bring this up because I would not want to see you loose your motor over it.

Remember an Ounce of prevention is worth a pound of Cure!

You mentioned possible adding a W/A system, check this out
http://forums.pelicanparts.com/showthread.php?t=455080

Question: What wastegate spring / boost pressure are you running?

Im not sure I want to run a wing so I am considering not installing the IC.
I will check the discharge to intake pipe and the rubber boot this weekend good tip and no offense taken! The newly installed boost gauge says I am running 10lb's!

[wanabe911 owner]

Originally Posted by mb911

Sound advice never want to run any debri through so check it out. and if you have a good sample I could always make a nice setup out of aluminum or stainless if you like?

That is great, what I want is to send you a picture of your exhaust and for you to tell me if you sent it this way. I think my installer may have modified your exhaust. Also I would like a wastegate dump that matches the tailpipe on your exhaust.

[mb911]

Originally Posted by wanabe911 owner

That is great, what I want is to send you a picture of your exhaust and for you to tell me if you sent it this way. I think my installer may have modified your exhaust. Also I would like a wastegate dump that matches the tailpipe on your exhaust.

We can do that (waste gate dump that matches exists)can I see the picture?

[wanabe911 owner]

Pictures of exhaust

[wanabe911 owner]

Just took my car for a ride and it started detonating really bad on the top end so I shut her down, so what do I do now? Do I have to install the IC, lower the boost level? Pull some timing?

[Dynamohum]

Originally Posted by wanabe911 owner

Just took my car for a ride and it started detonating really bad on the top end so I shut her down, so what do I do now? Do I have to install the IC, lower the boost level? Pull some timing?

Drop the boost or run a min of 107 Octane gas. I did some quick calculations using this calculator;

http://www.turbofast.com.au/TFcompB.html

95mm Bore = 3.74
74.4 mm Stroke =2.92
Ve = 92% As suggested to me by another member here, I was told to reverse calculate known values from Porsche engine HP data to arrive at VE and subtract a few percent.
Standard U.S. compression on 3.2 = 9.3 to 1
Your boost pressure = 10 psi

This means that you are running a Boost compression ratio of 13.84 to 1 @ 10 psi boost and need a min of 107 octane if you want your motor to stay together

Also you need an IC or W/A to cool the charge air. Personally for both our applications W/A is the quick fix as this will have the same effect as increasing your octane and reducing the charge temp at the same time. Considering where you live I would do both the IC and the W/A

Try dropping boost pressure and see what you and your motor can live with. Without an IC or W/A its all dependent on the ambient temp and octane of fuel you can find your AF ratio and ignition advance. Also what plugs are you running?
You need to drop about 3 heat ranges cooler now that your increasing your compression pressure under boost! To hot a plug will cause pre-ignition which if far worse than Detonation and you motor will only last a few seconds.

Do yourself a big Favor and Do Not Run your engine into detonation, it will do major damage

Please go to this link and read All the pages.
http://www.streetrodstuff.com/Articles/Engine/Detonation/Page_4.php

[mb911]

Wanabe That looks right to me

[Dynamohum]

There is some really good info here also
http://www.labontemotorsports.com/ontrack/WM101.pdf

The labonte system is looking really good to me from what I see so far. I'm sorta anal about research so will do more before I buy a system.
http://www.labontemotorsports.com/store/ccp0-catshow/Gasoline+Systems.html

I don't know if you checked this out? have a look at the dyno graphs on page 2
http://forums.pelicanparts.com/showthread.php?t=455080

[Fast951]

Interesting thread. I wonder why no one is going the MAF route? Why no one is getting a adjustable (fuel and ignition) to adjust over the Motronic to match the engine 100%?

The stock AFM is rated at around or less than 1000kg/hr flow, meaning it'll max out at relatively low HP. Under boost it'll generate 5V at lower RPM (regardless of position).

The AFM has a built-in Intake Air Temp (IAT). The IAT is used by the DME for calculations (fuel & ignition). This must be addressed and handled correctly when relocating the AFM to the pressure side (much hotter air).

I'm converting my 930 to EFI running a 3.2L Motronic with a blow-through MAF and Wasted Spark. The Motronic I'm using is enhanced to accept and interpret a MAP sensor to alter ignition based on boost. So the system wil have both MAF & MAP. If anyone interedted, I can document the conversion and share a few pictures as I progress.

[Dynamohum]

Originally Posted by wanabe911 owner

Just took my car for a ride and it started detonating really bad on the top end so I shut her down, so what do I do now? Do I have to install the IC, lower the boost level? Pull some timing?

40 years of pulling wrenches for a living has taught me that:
When trouble shooting, Never assume or take anything for granted!
Start with the basics and use a logical systematic process of elimination.

Do you have adequate fuel? An old fuel filter will reduce your flow. Is your fuel pressure adequate under load? Put a gauge on it and verify your reg is working properly.

Did they install the right chip?

Did they confirm your AF ratios with a wide band O2 sensor/ data log after the mods?

[Dynamohum]

Originally Posted by Fast951

Interesting thread. I wonder why no one is going the MAF route? Why no one is getting a adjustable (fuel and ignition) to adjust over the Motronic to match the engine 100%?

The stock AFM is rated at around or less than 1000kg/hr flow, meaning it'll max out at relatively low HP. Under boost it'll generate 5V at lower RPM (regardless of position).

The AFM has a built-in Intake Air Temp (IAT). The IAT is used by the DME for calculations (fuel & ignition). This must be addressed and handled correctly when relocating the AFM to the pressure side (much hotter air).

I'm converting my 930 to EFI running a 3.2L Motronic with a blow-through MAF and Wasted Spark. The Motronic I'm using is enhanced to accept and interpret a MAP sensor to alter ignition based on boost. So the system wil have both MAF & MAP. If anyone interedted, I can document the conversion and share a few pictures as I progress.

I realize there are limitations within the stock Motronic system, I would love to use the most advanced fuel and ignition system available, but I need to justify the cost vs the gains. My wallet is bleeding in every direction right now so for me its a matter of doing it in stages.

I'm very interested in learning more about your system and what your doing, please tell us more.

I was wondering about the charge temp and IAT reference output. Do you have a wide band O2 / data log? It would be great to see the actual effects of the IAT on the F/R....
Yes agree the barn door will swing open at much lower rpm, I would think that this should help with mid range fuel demands as the boost builds.
The Wide open throttle position switch comes into play at 3/4 throttle when adjusted properly and the DME switches to a rich WOT fuel map disregarding the O2 sensor input.
http://www.911chips.com/ignition.htm

You can also alter the cylinder head temp sender output to alter the A/F ratios.

Also there are internal adjustments in the DME that you can tune with.
http://www.911chips.com/fuelsys.html

I find all this so intriguing and looking forward to testing it.

I'm using TBC thermal barrier coatings in my build, this will affect the propagation of the fuel front, combustion temp, thermal load, etc. This means that I will have to work out a few other variables that will come into play and to tune properly, I will have to buy a programmable system.
At this point I still have allot to learn and sort out, so I'm taking a conservative systematic approach. First step is a good foundation to build on, ARP hardware, fresh motor and run a low boost within the confines of Motronics.
This is so addicting, I'm already obsessed with learning all I can! The upgrades will come as I further hone my tuning skills.