new to the porsche world, have some questions
#1
08-09-2007, 02:43 AM
new to the porsche world, have some questions
hi guys! I recently purchased an '87 944 non-turbo. It's taken me 7 Japaneses cars including Supras and Z cars to finally realize just how the European market can spoil you. I do, however, have a few questions about the 944. Now bear in mind that I am fairly mechanically inclined, I make my living off of cars, so I'm no stranger to them. While I've worked on a few Audis and Volkswagens, the European way of doing things is still a bit foreign to me...hopefully that will change with the 944.
My first question is about interchangeability and aftermarket parts as far as suspension is concerned. To put it simply, what are the differences between the M030 suspension, and the standard N/A or turbo suspension? is there anything specific that prevents a bolt-up swap between the two? Also, I've browsed around the Lindsey Racing website a bit, and taken interest in the aftermarket suspension they offer. Some of those setups have coil springs in the rear instead of torsion bars, does anyone know if those are designed to eliminate the torsion bars completely, or just serve as "helper" springs?
My second question is related to the drivetrain. I've searched around a bit, and found that the turbo S and S2 transaxles are the strongest from the 944 series. Are these 100% bolt-in upgrades for my 87 n/a, or are additional parts required? The reason I ask is because I'm considering an engine swap and am looking for a fairly bullet-proof setup (forgiving clutch drops, of course). I'd also like to know if the 968 6 speed transaxle is a bolt in as well, and what it's power capacity is, if anyone has any thoughts on it. Also, any power capacity issues with the torque tube?
My next question concerns troubleshooting. I have a mid to high RPM stumble during acceleration, and a hesitation when revving from idle. The car also shudders immediately after starting, almost zeroing out on the tach, then returning to normal idle around 650-700 with almost no variation, it's a very smooth idle. The shudder is avoidable by giving it a small amount of throttle during startup, but letting off from this quickly will cause a small amount of shudder as well. Normal revving then letting off will not cause it, only 1-5% throttle or so. I have replaced the plugs, cap, rotor, wires, fuel filter, rubber intake hose, and DME temp sensor. I have cleaned the AFM using the guide on clark's garage, but have not tested it. I have verified the throttle position sensor works as per clark's garage as well. I've also run a few bottles of good injector cleaner though it just to be safe. It sounds very much like a vacuum leak, but after trying the starting fluid trick I can't find any leak whatsoever. I can hear what sounds like a hiss coming from the throttle body area or underneath it, but I can't pinpoint it to any one thing and no amount of starting fluid causes a variance in RPM like a large leak should. Any suggestions or places to start looking from here? Could it be a fuel delivery problem in the pump/regulator/pulsation dampener?
Lastly, any suggestions on looking for wheels? I know the pattern is 5x130, but recommended offset and wheel width are beyond me. Ideally, I'd like to know what the widest 18" or 17" rim/tire size combo will fit on the 944 without significant modification (i.e. flares) and what offset is required for these combos.
Thanks in advance!
Nathan
My first question is about interchangeability and aftermarket parts as far as suspension is concerned. To put it simply, what are the differences between the M030 suspension, and the standard N/A or turbo suspension? is there anything specific that prevents a bolt-up swap between the two? Also, I've browsed around the Lindsey Racing website a bit, and taken interest in the aftermarket suspension they offer. Some of those setups have coil springs in the rear instead of torsion bars, does anyone know if those are designed to eliminate the torsion bars completely, or just serve as "helper" springs?
My second question is related to the drivetrain. I've searched around a bit, and found that the turbo S and S2 transaxles are the strongest from the 944 series. Are these 100% bolt-in upgrades for my 87 n/a, or are additional parts required? The reason I ask is because I'm considering an engine swap and am looking for a fairly bullet-proof setup (forgiving clutch drops, of course). I'd also like to know if the 968 6 speed transaxle is a bolt in as well, and what it's power capacity is, if anyone has any thoughts on it. Also, any power capacity issues with the torque tube?
My next question concerns troubleshooting. I have a mid to high RPM stumble during acceleration, and a hesitation when revving from idle. The car also shudders immediately after starting, almost zeroing out on the tach, then returning to normal idle around 650-700 with almost no variation, it's a very smooth idle. The shudder is avoidable by giving it a small amount of throttle during startup, but letting off from this quickly will cause a small amount of shudder as well. Normal revving then letting off will not cause it, only 1-5% throttle or so. I have replaced the plugs, cap, rotor, wires, fuel filter, rubber intake hose, and DME temp sensor. I have cleaned the AFM using the guide on clark's garage, but have not tested it. I have verified the throttle position sensor works as per clark's garage as well. I've also run a few bottles of good injector cleaner though it just to be safe. It sounds very much like a vacuum leak, but after trying the starting fluid trick I can't find any leak whatsoever. I can hear what sounds like a hiss coming from the throttle body area or underneath it, but I can't pinpoint it to any one thing and no amount of starting fluid causes a variance in RPM like a large leak should. Any suggestions or places to start looking from here? Could it be a fuel delivery problem in the pump/regulator/pulsation dampener?
Lastly, any suggestions on looking for wheels? I know the pattern is 5x130, but recommended offset and wheel width are beyond me. Ideally, I'd like to know what the widest 18" or 17" rim/tire size combo will fit on the 944 without significant modification (i.e. flares) and what offset is required for these combos.
Thanks in advance!
Nathan
#2
08-09-2007, 08:05 AM
RE: new to the porsche world, have some questions
ORIGINAL: wingman
hi guys! I recently purchased an '87 944 non-turbo. It's taken me 7 Japaneses cars including Supras and Z cars to finally realize just how the European market can spoil you. I do, however, have a few questions about the 944. Now bear in mind that I am fairly mechanically inclined, I make my living off of cars, so I'm no stranger to them. While I've worked on a few Audis and Volkswagens, the European way of doing things is still a bit foreign to me...hopefully that will change with the 944.
My first question is about interchangeability and aftermarket parts as far as suspension is concerned. To put it simply, what are the differences between the M030 suspension, and the standard N/A or turbo suspension? is there anything specific that prevents a bolt-up swap between the two? Also, I've browsed around the Lindsey Racing website a bit, and taken interest in the aftermarket suspension they offer. Some of those setups have coil springs in the rear instead of torsion bars, does anyone know if those are designed to eliminate the torsion bars completely, or just serve as "helper" springs?
My second question is related to the drivetrain. I've searched around a bit, and found that the turbo S and S2 transaxles are the strongest from the 944 series. Are these 100% bolt-in upgrades for my 87 n/a, or are additional parts required? The reason I ask is because I'm considering an engine swap and am looking for a fairly bullet-proof setup (forgiving clutch drops, of course). I'd also like to know if the 968 6 speed transaxle is a bolt in as well, and what it's power capacity is, if anyone has any thoughts on it. Also, any power capacity issues with the torque tube?
My next question concerns troubleshooting. I have a mid to high RPM stumble during acceleration, and a hesitation when revving from idle. The car also shudders immediately after starting, almost zeroing out on the tach, then returning to normal idle around 650-700 with almost no variation, it's a very smooth idle. The shudder is avoidable by giving it a small amount of throttle during startup, but letting off from this quickly will cause a small amount of shudder as well. Normal revving then letting off will not cause it, only 1-5% throttle or so. I have replaced the plugs, cap, rotor, wires, fuel filter, rubber intake hose, and DME temp sensor. I have cleaned the AFM using the guide on clark's garage, but have not tested it. I have verified the throttle position sensor works as per clark's garage as well. I've also run a few bottles of good injector cleaner though it just to be safe. It sounds very much like a vacuum leak, but after trying the starting fluid trick I can't find any leak whatsoever. I can hear what sounds like a hiss coming from the throttle body area or underneath it, but I can't pinpoint it to any one thing and no amount of starting fluid causes a variance in RPM like a large leak should. Any suggestions or places to start looking from here? Could it be a fuel delivery problem in the pump/regulator/pulsation dampener?
Lastly, any suggestions on looking for wheels? I know the pattern is 5x130, but recommended offset and wheel width are beyond me. Ideally, I'd like to know what the widest 18" or 17" rim/tire size combo will fit on the 944 without significant modification (i.e. flares) and what offset is required for these combos.
Thanks in advance!
Nathan
hi guys! I recently purchased an '87 944 non-turbo. It's taken me 7 Japaneses cars including Supras and Z cars to finally realize just how the European market can spoil you. I do, however, have a few questions about the 944. Now bear in mind that I am fairly mechanically inclined, I make my living off of cars, so I'm no stranger to them. While I've worked on a few Audis and Volkswagens, the European way of doing things is still a bit foreign to me...hopefully that will change with the 944.
My first question is about interchangeability and aftermarket parts as far as suspension is concerned. To put it simply, what are the differences between the M030 suspension, and the standard N/A or turbo suspension? is there anything specific that prevents a bolt-up swap between the two? Also, I've browsed around the Lindsey Racing website a bit, and taken interest in the aftermarket suspension they offer. Some of those setups have coil springs in the rear instead of torsion bars, does anyone know if those are designed to eliminate the torsion bars completely, or just serve as "helper" springs?
My second question is related to the drivetrain. I've searched around a bit, and found that the turbo S and S2 transaxles are the strongest from the 944 series. Are these 100% bolt-in upgrades for my 87 n/a, or are additional parts required? The reason I ask is because I'm considering an engine swap and am looking for a fairly bullet-proof setup (forgiving clutch drops, of course). I'd also like to know if the 968 6 speed transaxle is a bolt in as well, and what it's power capacity is, if anyone has any thoughts on it. Also, any power capacity issues with the torque tube?
My next question concerns troubleshooting. I have a mid to high RPM stumble during acceleration, and a hesitation when revving from idle. The car also shudders immediately after starting, almost zeroing out on the tach, then returning to normal idle around 650-700 with almost no variation, it's a very smooth idle. The shudder is avoidable by giving it a small amount of throttle during startup, but letting off from this quickly will cause a small amount of shudder as well. Normal revving then letting off will not cause it, only 1-5% throttle or so. I have replaced the plugs, cap, rotor, wires, fuel filter, rubber intake hose, and DME temp sensor. I have cleaned the AFM using the guide on clark's garage, but have not tested it. I have verified the throttle position sensor works as per clark's garage as well. I've also run a few bottles of good injector cleaner though it just to be safe. It sounds very much like a vacuum leak, but after trying the starting fluid trick I can't find any leak whatsoever. I can hear what sounds like a hiss coming from the throttle body area or underneath it, but I can't pinpoint it to any one thing and no amount of starting fluid causes a variance in RPM like a large leak should. Any suggestions or places to start looking from here? Could it be a fuel delivery problem in the pump/regulator/pulsation dampener?
Lastly, any suggestions on looking for wheels? I know the pattern is 5x130, but recommended offset and wheel width are beyond me. Ideally, I'd like to know what the widest 18" or 17" rim/tire size combo will fit on the 944 without significant modification (i.e. flares) and what offset is required for these combos.
Thanks in advance!
Nathan
As far as sway bars go, there were a few options. The 1986 turbo sway bars were 24mm fronts. The later turbo sway bars 87 were a 25.5mm front bar. Then there was the M030 944 bar, which was a 26.8mm sway bar. I believe the rear sway bar stayed the same in the turbos at 18mm. Then there was the 968 M030 sway bars which were 30mm front and a 19mm adjustable rear. The 968 bars are the most desirable among the turbo guys. On an NA car, a good upgrade would be any of the turbo bars, but I would probably look for at least a 25.5mm setup. They will all bolt right up with the proper sized bushings.
In regards to a coilover suspension. You can run rear coilovers with torsion bars, or without torsion bars. Your spring rate will depend on which you decide to do.
In terms of transaxles. All mentioned will bolt up to your car. The S2 had a stonger R&P (the R&P was also geared lower), while the Turbo S had hardened 1st and 2nd gears. If you do clutch drops, you are still going to blow those out eventually as well. You absolutely must ease the car off the line. The trick setup is to take a Turbo S transaxle and install the S2 R&P. Powerwise, it will hold over 600whp easily if you take care of it. Same goes for the torque tube.
In terms of the running issues, it sounds like a deadspot in the AFM, or the TPS to me.
Most newer style Porsche rims will fit the 87 and later cars. You can put on boxster or 996 rims, though the 996 C2 18" rims are a tight fit in the rear. You are looking at about a 52.2mm offset.
Thats all I know, it's too early.
#3
08-09-2007, 10:07 PM
RE: new to the porsche world, have some questions
thanks for the info! I have to wonder though, since I'm no physics junkie, if there are any adverse handling effects involved with eliminating the torsion bars in contrast to keeping them with rear coil springs. Not only that, but any thoughts on the actual shock mounting point on the arm being able to support a setup like that? I'm sure I can reinforce it, but it never hurt to ask. As far as swaybars, I'll probably go with the aftermarket ones available through lindsey racing, now that I have a pretty good idea on the differences between the turbo and n/a platforms.
I took a visit to a porsche wrecking yard in town and they don't have any S2 or S transaxles, and they want $1500 for a limited slip turbo transaxle. Is this asking a little much, and would it be capable of sustaining about 500 horsepower (i always ease off the line, just an FYI)? And just for clarification, does the 968 transaxle bolt up or not?
again, thanks for your help! I hope to start gathering parts for it pretty soon...just doing the research right now.
I took a visit to a porsche wrecking yard in town and they don't have any S2 or S transaxles, and they want $1500 for a limited slip turbo transaxle. Is this asking a little much, and would it be capable of sustaining about 500 horsepower (i always ease off the line, just an FYI)? And just for clarification, does the 968 transaxle bolt up or not?
again, thanks for your help! I hope to start gathering parts for it pretty soon...just doing the research right now.
#4
08-10-2007, 10:32 AM
RE: new to the porsche world, have some questions
Yes, the 968 transaxle bolts up. You will spend at least $2500 for a used 6 speed.
$1500 for a turbo LSD tranny is a good price. It will support the hp if you are careful.
What kind of engine are you planning for 500whp?
As far as the rear carrier goes, none of your mounts are removed when you remove the torsion bars, everything stays the same, so there is no additional stress on the trailing arms, spring plates, shocks, etc.
$1500 for a turbo LSD tranny is a good price. It will support the hp if you are careful.
What kind of engine are you planning for 500whp?
As far as the rear carrier goes, none of your mounts are removed when you remove the torsion bars, everything stays the same, so there is no additional stress on the trailing arms, spring plates, shocks, etc.
#5
08-10-2007, 05:23 PM
RE: new to the porsche world, have some questions
i'm actually considering a GM LS6, I know how a lot of people are purists, especially with the european market, but after speaking with many local 944T and 928 owners, and doing quite a bit of my own independent research, I've come to the conclusion it's the best route to take with what I'd like to do.
I'll talk to the junkyard about a 968 transaxle...even though looking at the gear ratios it won't gain me anything, just give me an extra gear I have to shift through. So much for hoping for T-56 like ratios. Thanks for the information on the rear suspension though, it's much appreciated! Hopefully I'll be able to get my project underway soon.
I'll talk to the junkyard about a 968 transaxle...even though looking at the gear ratios it won't gain me anything, just give me an extra gear I have to shift through. So much for hoping for T-56 like ratios. Thanks for the information on the rear suspension though, it's much appreciated! Hopefully I'll be able to get my project underway soon.
#6
08-10-2007, 07:22 PM
RE: new to the porsche world, have some questions
I know a guy that put an LS1 in his 86, then he put a blower on it. The car moves!
#7
08-10-2007, 08:20 PM
RE: new to the porsche world, have some questions
wow! ls1 porsche's scoot as it is, but a blower? that's a bit too much car and too little life expectancy for someone like me. how does he ever find traction?
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