951S Rough engine - looking for Bay Area garage
05-07-2013, 02:34 PM
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Igor, what was your WBO2 telling you regarding AFRs? In your previous thread, it was pretty clear you were running rich.
I have lots of people running the A/M-Tune on track cars without issue. So fuel delivery is the first thing thing I would look at. Additionally, if your AFM doesn't go up to 4.6volts you might be overrunning it - which would cause the motor to enlean once the AFM is maxed.
I have lots of people running the A/M-Tune on track cars without issue. So fuel delivery is the first thing thing I would look at. Additionally, if your AFM doesn't go up to 4.6volts you might be overrunning it - which would cause the motor to enlean once the AFM is maxed.
05-07-2013, 02:53 PM
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Thanks for the quick reply. Honestly I never finished installing the WBO2 guage (I know I should have) and so can't tell you. However your comment made me think : since there is a distinct petrol smell coming from cylinder 4 maybe there was/is an issue with fuel delivery which starved it of fuel resulting in a lean mixture in that particular cylinder.
I'm at work now and won't be able to answer comments quickly, but everyone please continue writing. I will try to read your comments and suggestions as soon as I can.
Thank you.
I'm at work now and won't be able to answer comments quickly, but everyone please continue writing. I will try to read your comments and suggestions as soon as I can.
Thank you.
05-07-2013, 03:33 PM
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Hello everyone,
Sorry for not answering sooner. I appreciate everyones contribution to this thread. Unfortunately I had already brought the car to the mechanic and could not do the checks suggested. In any case I spoke with the head mechanic yesterday and he told me he performed the leak-down test which pointed towards a valve leak, he then removed the head and confirmed the exhaust valve on cylinder 4 is burned. He also told me that in 2011 they did not perform a head rebuild but just replaced the head gasket. At the time the valves were OK and did not need attention.
He also said that most likely the valve burned because after performing the upgrades listed above the engine was running too lean for the added power at high RPMs and that this increases the temperature in the cylinders which results in burning the valves. He says that everything else is fine.
So I need to replace 4 exhaust valves. This is a 1988 944 Turbo S and I know that Porsche used special exhaust valves, larger sodium cooled exhaust valves, for this model compared to the normal 944 Turbo. I would like to replace the exhaust valves with this model's original valves or, as I do take this on the track every once in a while, with upgraded performance exhaust valves (and maybe valve springs at that point), if they exist (I could not find any information on performance exhaust valves, only springs). Can anyone please suggest which exhaust valves I should install and where I can get them. I know original Porsche valves (however I'm not sure they are the S model version) are around $150 each as opposed to half or less for aftermarket ones, however I prefer to have the original or upgraded ones, even if it costs more.
Also, since the cylinder head has been removed, are there any other, not highly expensive, upgrades I can do?
Finally the mechanic suggested, after he has finished the engine work, that I bring the car to a tuner to have the chip mapped appropriately for the state it is in. I have a Rogue's A-Tune Package installed and I thought this was mapped correctly for the increase in boost. Do I have to get this chip remapped by a tuner? If so can someone suggest a tuner in the Bay Area?
Thank you all once again for you comments and help. Please let me know about the exhaust valves and any additional upgrades you think I should do as soon as you can. I would like to advice the mechanic later today as to what I'm planning on doing.
Thank you all so much.
Igor
Sorry for not answering sooner. I appreciate everyones contribution to this thread. Unfortunately I had already brought the car to the mechanic and could not do the checks suggested. In any case I spoke with the head mechanic yesterday and he told me he performed the leak-down test which pointed towards a valve leak, he then removed the head and confirmed the exhaust valve on cylinder 4 is burned. He also told me that in 2011 they did not perform a head rebuild but just replaced the head gasket. At the time the valves were OK and did not need attention.
He also said that most likely the valve burned because after performing the upgrades listed above the engine was running too lean for the added power at high RPMs and that this increases the temperature in the cylinders which results in burning the valves. He says that everything else is fine.
So I need to replace 4 exhaust valves. This is a 1988 944 Turbo S and I know that Porsche used special exhaust valves, larger sodium cooled exhaust valves, for this model compared to the normal 944 Turbo. I would like to replace the exhaust valves with this model's original valves or, as I do take this on the track every once in a while, with upgraded performance exhaust valves (and maybe valve springs at that point), if they exist (I could not find any information on performance exhaust valves, only springs). Can anyone please suggest which exhaust valves I should install and where I can get them. I know original Porsche valves (however I'm not sure they are the S model version) are around $150 each as opposed to half or less for aftermarket ones, however I prefer to have the original or upgraded ones, even if it costs more.
Also, since the cylinder head has been removed, are there any other, not highly expensive, upgrades I can do?
Finally the mechanic suggested, after he has finished the engine work, that I bring the car to a tuner to have the chip mapped appropriately for the state it is in. I have a Rogue's A-Tune Package installed and I thought this was mapped correctly for the increase in boost. Do I have to get this chip remapped by a tuner? If so can someone suggest a tuner in the Bay Area?
Thank you all once again for you comments and help. Please let me know about the exhaust valves and any additional upgrades you think I should do as soon as you can. I would like to advice the mechanic later today as to what I'm planning on doing.
Thank you all so much.
Igor
Edit I just read the above post .... I realized you probably know this but
IMHO you should never run your boost up with a WB .... Not checking your AFR is like playing Russian Roulette.....
05-07-2013, 04:03 PM
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From your description it sounds like you have a competent mechanic. At this point I would recommend doing a complete valve job, not just the exhaust valves. You should check the AFR, as your mechanic noted, it could cause premature failure (head gasket, valves, pistons) in the future. With those 2 items corrected, you should be ables to keep the engine closed up to at least the 200k mark (barring hi-rev or other abuse).
05-07-2013, 07:25 PM
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Thank you for your posts. I will check with my mechanic regarding the extra expense of having both intake an exhaust valves done. If I do have both done (as well as the springs) which valves would you recommend replacing them with? Also should I have the injectors replaced as well? I was looking at Lindsey Racing performance valve springs and flow matched injectors. Are these good replacements or are there better options?
05-08-2013, 04:49 PM
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I just spoke with my mechanic and he said labor wise the expense of having both the intake and exhaust valves done is the same as having just the exhaust ones done. So at this point I am planning on doing the following:
- replace intake and exhaust valves with aftermarket ones (not genuine Porsche ones as they are MUCH more expensive at ~ $100 more each)
For this I have three choices
- Lindsey Racing
- INTAKE VALVE 944T Price: $47.95 Each Brand: Doesn't say
- EXHAUST VALVE 944T Price: $55.05 Each Brand: Doesn't say
- Pelican Parts
- Intake Valve, 944 Turbo (1986-89) $42 Each Brand: Intervalves
- Exhaust Valve, 944 Turbo (1986-89) $35.25 Each Brand: AE
- My mechanic can get a set of TRW valves for about $60 each (I also found them online for about this price). From what I have read here on Rennlist I seem to understand that TRW was the original manufacturer for the Porsche valves and therefore would be identical to the original ones. On EBay I also found a seller with excellent rating selling TRW Exhaust valves for $20 each. This seems too low to be true however.
- LINDSEY RACING VALVE SPRINGS 944 8v / 944T Spring Rate 140# Installed Height with Moly Retainers for stock hydraulic lifters $393.95
- Victor Reinz "Wide Fire Ring" Head Gasket Set $182.95
What are you opinions on the above? Especially on the three valve options? Keep in mind that I do maybe 4-5 track days a year. Additionally I am planning on ordering the following to do a complete tune up to the car, which I have never done since I got it about 10 months ago:
- Lindsey Racing PERFORMANCE FIREBRAID IGNITION WIRE SET $169.95
- MSD Ignition 8202 - MSD Blaster 2 Ignition Coil from Summit Racing $39.95
- Replace Spark Plugs with new NGK BPR7ES ones from Rock Auto
- Distributor Cap Original Bosch from Pelican Parts $42.00
- Ignition Rotor Original Bosch from Pelican Parts $41.50
- OEM Air Filter from Pelican Parts $15.75
- Genuine Porsche Fuel Filter from Pelican Parts $25.50
I would like to give a definitive answer to my mechanic today as he is waiting for my input to continue. Also, as this is my only vehicle, I need to get is done as soon as possible - riding the bike to work is fun and all, but I really can't use it to go to the opera house Saturday evening!
Thank you all for your help and suggestions.
Igor
- replace intake and exhaust valves with aftermarket ones (not genuine Porsche ones as they are MUCH more expensive at ~ $100 more each)
For this I have three choices
- Lindsey Racing
- INTAKE VALVE 944T Price: $47.95 Each Brand: Doesn't say
- EXHAUST VALVE 944T Price: $55.05 Each Brand: Doesn't say
- Pelican Parts
- Intake Valve, 944 Turbo (1986-89) $42 Each Brand: Intervalves
- Exhaust Valve, 944 Turbo (1986-89) $35.25 Each Brand: AE
- My mechanic can get a set of TRW valves for about $60 each (I also found them online for about this price). From what I have read here on Rennlist I seem to understand that TRW was the original manufacturer for the Porsche valves and therefore would be identical to the original ones. On EBay I also found a seller with excellent rating selling TRW Exhaust valves for $20 each. This seems too low to be true however.
- LINDSEY RACING VALVE SPRINGS 944 8v / 944T Spring Rate 140# Installed Height with Moly Retainers for stock hydraulic lifters $393.95
- Victor Reinz "Wide Fire Ring" Head Gasket Set $182.95
What are you opinions on the above? Especially on the three valve options? Keep in mind that I do maybe 4-5 track days a year. Additionally I am planning on ordering the following to do a complete tune up to the car, which I have never done since I got it about 10 months ago:
- Lindsey Racing PERFORMANCE FIREBRAID IGNITION WIRE SET $169.95
- MSD Ignition 8202 - MSD Blaster 2 Ignition Coil from Summit Racing $39.95
- Replace Spark Plugs with new NGK BPR7ES ones from Rock Auto
- Distributor Cap Original Bosch from Pelican Parts $42.00
- Ignition Rotor Original Bosch from Pelican Parts $41.50
- OEM Air Filter from Pelican Parts $15.75
- Genuine Porsche Fuel Filter from Pelican Parts $25.50
I would like to give a definitive answer to my mechanic today as he is waiting for my input to continue. Also, as this is my only vehicle, I need to get is done as soon as possible - riding the bike to work is fun and all, but I really can't use it to go to the opera house Saturday evening!
Thank you all for your help and suggestions.
Igor
05-08-2013, 05:47 PM
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I just spoke with my mechanic and he said labor wise the expense of having both the intake and exhaust valves done is the same as having just the exhaust ones done. So at this point I am planning on doing the following:
- replace intake and exhaust valves with aftermarket ones (not genuine Porsche ones as they are MUCH more expensive at ~ $100 more each)
For this I have three choices
- Lindsey Racing
- INTAKE VALVE 944T Price: $47.95 Each Brand: Doesn't say
- EXHAUST VALVE 944T Price: $55.05 Each Brand: Doesn't say
- Pelican Parts
- Intake Valve, 944 Turbo (1986-89) $42 Each Brand: Intervalves
- Exhaust Valve, 944 Turbo (1986-89) $35.25 Each Brand: AE
- My mechanic can get a set of TRW valves for about $60 each (I also found them online for about this price). From what I have read here on Rennlist I seem to understand that TRW was the original manufacturer for the Porsche valves and therefore would be identical to the original ones. On EBay I also found a seller with excellent rating selling TRW Exhaust valves for $20 each. This seems too low to be true however.
- LINDSEY RACING VALVE SPRINGS 944 8v / 944T Spring Rate 140# Installed Height with Moly Retainers for stock hydraulic lifters $393.95
- Victor Reinz "Wide Fire Ring" Head Gasket Set $182.95
What are you opinions on the above? Especially on the three valve options? Keep in mind that I do maybe 4-5 track days a year. Additionally I am planning on ordering the following to do a complete tune up to the car, which I have never done since I got it about 10 months ago:
- Lindsey Racing PERFORMANCE FIREBRAID IGNITION WIRE SET $169.95
- MSD Ignition 8202 - MSD Blaster 2 Ignition Coil from Summit Racing $39.95
- Replace Spark Plugs with new NGK BPR7ES ones from Rock Auto
- Distributor Cap Original Bosch from Pelican Parts $42.00
- Ignition Rotor Original Bosch from Pelican Parts $41.50
- OEM Air Filter from Pelican Parts $15.75
- Genuine Porsche Fuel Filter from Pelican Parts $25.50
I would like to give a definitive answer to my mechanic today as he is waiting for my input to continue. Also, as this is my only vehicle, I need to get is done as soon as possible - riding the bike to work is fun and all, but I really can't use it to go to the opera house Saturday evening!
Thank you all for your help and suggestions.
Igor
- replace intake and exhaust valves with aftermarket ones (not genuine Porsche ones as they are MUCH more expensive at ~ $100 more each)
For this I have three choices
- Lindsey Racing
- INTAKE VALVE 944T Price: $47.95 Each Brand: Doesn't say
- EXHAUST VALVE 944T Price: $55.05 Each Brand: Doesn't say
- Pelican Parts
- Intake Valve, 944 Turbo (1986-89) $42 Each Brand: Intervalves
- Exhaust Valve, 944 Turbo (1986-89) $35.25 Each Brand: AE
- My mechanic can get a set of TRW valves for about $60 each (I also found them online for about this price). From what I have read here on Rennlist I seem to understand that TRW was the original manufacturer for the Porsche valves and therefore would be identical to the original ones. On EBay I also found a seller with excellent rating selling TRW Exhaust valves for $20 each. This seems too low to be true however.
- LINDSEY RACING VALVE SPRINGS 944 8v / 944T Spring Rate 140# Installed Height with Moly Retainers for stock hydraulic lifters $393.95
- Victor Reinz "Wide Fire Ring" Head Gasket Set $182.95
What are you opinions on the above? Especially on the three valve options? Keep in mind that I do maybe 4-5 track days a year. Additionally I am planning on ordering the following to do a complete tune up to the car, which I have never done since I got it about 10 months ago:
- Lindsey Racing PERFORMANCE FIREBRAID IGNITION WIRE SET $169.95
- MSD Ignition 8202 - MSD Blaster 2 Ignition Coil from Summit Racing $39.95
- Replace Spark Plugs with new NGK BPR7ES ones from Rock Auto
- Distributor Cap Original Bosch from Pelican Parts $42.00
- Ignition Rotor Original Bosch from Pelican Parts $41.50
- OEM Air Filter from Pelican Parts $15.75
- Genuine Porsche Fuel Filter from Pelican Parts $25.50
I would like to give a definitive answer to my mechanic today as he is waiting for my input to continue. Also, as this is my only vehicle, I need to get is done as soon as possible - riding the bike to work is fun and all, but I really can't use it to go to the opera house Saturday evening!
Thank you all for your help and suggestions.
Igor
It's your car and your money ... and of course your choice
Good luck either way ...
05-08-2013, 05:58 PM
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Hi Crazy Eddie,
I did request a quote for parts from Sunset and am waiting for a reply. If the price of genuine Porsche exhaust valves purchased from them is not that much higher than aftermarket ones (I think I would accept a price of at most $100 each), then I will definitely go with them.
However at the moment I have no idea what their price is.
Thanks for the comment.
Igor
I did request a quote for parts from Sunset and am waiting for a reply. If the price of genuine Porsche exhaust valves purchased from them is not that much higher than aftermarket ones (I think I would accept a price of at most $100 each), then I will definitely go with them.
However at the moment I have no idea what their price is.
Thanks for the comment.
Igor
05-08-2013, 06:15 PM
#26
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Hi Crazy Eddie,
I did request a quote for parts from Sunset and am waiting for a reply. If the price of genuine Porsche exhaust valves purchased from them is not that much higher than aftermarket ones (I think I would accept a price of at most $100 each), then I will definitely go with them.
However at the moment I have no idea what their price is.
Thanks for the comment.
Igor
I did request a quote for parts from Sunset and am waiting for a reply. If the price of genuine Porsche exhaust valves purchased from them is not that much higher than aftermarket ones (I think I would accept a price of at most $100 each), then I will definitely go with them.
However at the moment I have no idea what their price is.
Thanks for the comment.
Igor
They probably will be more....
There is something to be said for Genuine Porsche parts in most case ( but not all ) this might be one, but in truth, I am not best qualified to answer that. Hopefully some engine builders will chime in and give you their take on it
They( Sunset) can be pretty competitive most times, but sometimes they are way out there
They do take longer sometimes, as they don't carry a heavy inventory...
Best of luck
Ed
05-09-2013, 12:32 AM
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Igor, have you gone down and looked at the valves your mechanic says are burned? Something about your mechanic's story seems curious, including the comment about needing to get a chip tuned. As I understand it, Rogue's A-tune is tailor-tuned for your car, and it seems odd to me that you could run lean enough to burn a valve so abruptly, but not first blow your head gasket. It's possible, but I'd personally want to check out the parts to see for myself. If you did burn a valve, then you'll want to get to the bottom of that before strapping new expensive parts on the car and driving around, though I'm not aware of anyone in the bay area who would be particularly helpful in tuning a 951 DME chip. As others have said, a wideband would be your best bet, and the zeitronix system with exhaust gas sensor would be even better. If you are indeed running lean, you could then see it in action and be armed to figure out why.
Having said all that, if you do need all the parts your mechanic is recommending, you might consider getting an off-the-shelf, ready to run, rebuilt head from Lindsey. They're cheap and ready to go...
Having said all that, if you do need all the parts your mechanic is recommending, you might consider getting an off-the-shelf, ready to run, rebuilt head from Lindsey. They're cheap and ready to go...
05-09-2013, 08:55 PM
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Tom M'Guinn, thank you for your post. My mechanic seems very reliable and trustworthy, and I really do have no doubt he is honest and truthful in his assessment. But I do appreciate your thoughts. I really do think it has something to do with the injector on cylinder 4, however I won't know until the head is back on.
I therefore decided to order original Porsche intake and exhaust valves from Sunset Porsche in Oregon. Their prices are the best I could find (thanks Crazy Eddie) for original valves at $117 each. I also ordered a new set of original valve springs from them at $20 each.
I decided I prefer to invest on original Porsche parts rather than save some money on aftermarket valves and then spend it on a set of upgraded Lindsey valve springs. Unfortunately the intake valves have to arrive from Germany and so I have to wait another week to get them. So, if all goes well, in about two weeks I should have my car up and running again.
At that point I will definitely finish hooking up the WBO2 gauge so that I can anticipate and hopefully avoid a similar problem in the future. I'll keep you guys posted.
Igor
I therefore decided to order original Porsche intake and exhaust valves from Sunset Porsche in Oregon. Their prices are the best I could find (thanks Crazy Eddie) for original valves at $117 each. I also ordered a new set of original valve springs from them at $20 each.
I decided I prefer to invest on original Porsche parts rather than save some money on aftermarket valves and then spend it on a set of upgraded Lindsey valve springs. Unfortunately the intake valves have to arrive from Germany and so I have to wait another week to get them. So, if all goes well, in about two weeks I should have my car up and running again.
At that point I will definitely finish hooking up the WBO2 gauge so that I can anticipate and hopefully avoid a similar problem in the future. I'll keep you guys posted.
Igor
05-09-2013, 09:58 PM
#29
you never know until the engine is opened up. But i agree with Tom
What i can gather is
Recent engine work which included a new head in 2011
Past due maintenance (spark plug wires shouldnt be falling apart or ripped)
A tune with boost turned to the max with no way to check the AFR (insert comment)
Everything is being relayed 3rd person from the mechanic.
What i can gather is
Recent engine work which included a new head in 2011
Past due maintenance (spark plug wires shouldnt be falling apart or ripped)
A tune with boost turned to the max with no way to check the AFR (insert comment)
Everything is being relayed 3rd person from the mechanic.
05-09-2013, 10:42 PM
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Hi Carlege. Thanks for your post.
Regarding the new head in 2011, actually only the head gasket was replaced. The head was fine at the time and no work was done to it. So this 951 has had it's original head and valves for about 140k miles. I certainly did my part in accelerating their demise by pushing the boost without checking the AFR.
Regarding the new head in 2011, actually only the head gasket was replaced. The head was fine at the time and no work was done to it. So this 951 has had it's original head and valves for about 140k miles. I certainly did my part in accelerating their demise by pushing the boost without checking the AFR.