Ask me Anything - I run a 3.2 engine in a 996 cabriolet
05-24-2020, 11:56 PM
#1
Rennlist Member
Thread Starter
Ask me Anything - I run a 3.2 engine in a 996 cabriolet
Hi All
This topic has come up a few times and people seem to talk about it with hushed understanding - you get why someone would cut their losses and spring for 92% of the stock engine but you don’t really want to admit it. Well I’m here to tell you about how I did it and I’m pretty happy.
I got my 2001 Carrera 4 Cabriolet for next to nothing with a blown engine on a sign of goodwill from someone who wanted to see it driven and not stripped for parts; it had just over 125,000. At the time I was working in public service and this was literally the closest I ever imagined myself to living the 911 life. I Even at one point debated between a 2.7 and 3.2 but ultimately a 3.2 with a recent IMS replacement popped up on EBay and I took the plunge for about $3,000 shipped to my door. The engine cost was covered almost exactly by selling the 944 I was driving at the time.
At the time I was pretty set on saving up for a 3.4 after getting whatever engine I got.
After I got the engine i originally ran it with the Boxster intake, fuel lines, and non stock exhaust because I was nervous about having the bosses drilled on the 3.2 head to accept the 3.4 intake and fuel lines. This was a big mistake- I ended up having to alter a lot of stuff to accommodate the Boxster accessories and placement but it was one of those situations where once I realized how much easier(even if a little terrifying) drilling the holes would be it was too late. I got the car running about 4 months after receiving it working on it really occasionally. I had to fix a few things over the last three years but more or less, everything worked without too much drama.
I never tuned the ECU because it ran pretty consistently without triggering any CELs. I averaged around 16.5-17mpg which seemed a little low. But I also mostly drive in the city. The car was really peaky and revved fast up high. Another side effect of not drilling the head is that my exhaust was not fantastic(Boxster headers and first cats to an x pipe style muffler and then exit) it droned super bad around 2,500rpm. I put about 7,500 pretty happy miles on the car in that setup.
More recently I decided to drop the engine and drill the bosses in the head for the intake and exhaust hangers spurred in part by oil leaking from the AOS(pretty sure it was the line that connects now that I pulled it out). I actually just got back from my maiden voyage after doing this work(I also converted to RWD) and took it very easy because I had so much pulled apart and want to take it easy for a bit to listen and feel for loose bolts and such. I will give it a drive or two or three to figure out if it actually feels faster but the math says it should be with the larger intake and exhaust from the 3.4. I long ago sold the original mid pipes/cats from the car because they were coolant and oil soaked when the engine kaboomed for the original owner to a cat recycler. So my car is pretty much everything stock but with the DesignTek 200 cell cats.
So that’s the story of a guy who was too poor(at the time) for even the cheapest 911, making it work with a donor car and a 3.2. Now a days I’ve moved into more lucrative work but still not sure if I’ll end up with another 911. Most likely I will keep an on Caymans(yes, a blaspheme like me would even consider a 4 cylinder) so I have a coupe and a drop top. But first I’m putting my money to other good uses. One thing is almost certain, I am no longer considering the move to a 3.4 - I would consider doing a full on rebuild of an M96 with nikkies and larger pistons but there is no way I’d replace what I have with a stock 3.4; just not enough difference and anecdotally the 3.2 has less chance of failure.
If you have any questions, let me know. I’m sure the car is better with the 3.4 but I also know that it sucks how many people part their cars because they don’t have the money for a Rebuild and the cost/risk of a used 3.4 is high so they don’t know what else to do. So I wanted to tell my story so people consider the option of a 3.2. It’s not for everyone but it certainly works.
This topic has come up a few times and people seem to talk about it with hushed understanding - you get why someone would cut their losses and spring for 92% of the stock engine but you don’t really want to admit it. Well I’m here to tell you about how I did it and I’m pretty happy.
I got my 2001 Carrera 4 Cabriolet for next to nothing with a blown engine on a sign of goodwill from someone who wanted to see it driven and not stripped for parts; it had just over 125,000. At the time I was working in public service and this was literally the closest I ever imagined myself to living the 911 life. I Even at one point debated between a 2.7 and 3.2 but ultimately a 3.2 with a recent IMS replacement popped up on EBay and I took the plunge for about $3,000 shipped to my door. The engine cost was covered almost exactly by selling the 944 I was driving at the time.
At the time I was pretty set on saving up for a 3.4 after getting whatever engine I got.
After I got the engine i originally ran it with the Boxster intake, fuel lines, and non stock exhaust because I was nervous about having the bosses drilled on the 3.2 head to accept the 3.4 intake and fuel lines. This was a big mistake- I ended up having to alter a lot of stuff to accommodate the Boxster accessories and placement but it was one of those situations where once I realized how much easier(even if a little terrifying) drilling the holes would be it was too late. I got the car running about 4 months after receiving it working on it really occasionally. I had to fix a few things over the last three years but more or less, everything worked without too much drama.
I never tuned the ECU because it ran pretty consistently without triggering any CELs. I averaged around 16.5-17mpg which seemed a little low. But I also mostly drive in the city. The car was really peaky and revved fast up high. Another side effect of not drilling the head is that my exhaust was not fantastic(Boxster headers and first cats to an x pipe style muffler and then exit) it droned super bad around 2,500rpm. I put about 7,500 pretty happy miles on the car in that setup.
More recently I decided to drop the engine and drill the bosses in the head for the intake and exhaust hangers spurred in part by oil leaking from the AOS(pretty sure it was the line that connects now that I pulled it out). I actually just got back from my maiden voyage after doing this work(I also converted to RWD) and took it very easy because I had so much pulled apart and want to take it easy for a bit to listen and feel for loose bolts and such. I will give it a drive or two or three to figure out if it actually feels faster but the math says it should be with the larger intake and exhaust from the 3.4. I long ago sold the original mid pipes/cats from the car because they were coolant and oil soaked when the engine kaboomed for the original owner to a cat recycler. So my car is pretty much everything stock but with the DesignTek 200 cell cats.
So that’s the story of a guy who was too poor(at the time) for even the cheapest 911, making it work with a donor car and a 3.2. Now a days I’ve moved into more lucrative work but still not sure if I’ll end up with another 911. Most likely I will keep an on Caymans(yes, a blaspheme like me would even consider a 4 cylinder) so I have a coupe and a drop top. But first I’m putting my money to other good uses. One thing is almost certain, I am no longer considering the move to a 3.4 - I would consider doing a full on rebuild of an M96 with nikkies and larger pistons but there is no way I’d replace what I have with a stock 3.4; just not enough difference and anecdotally the 3.2 has less chance of failure.
If you have any questions, let me know. I’m sure the car is better with the 3.4 but I also know that it sucks how many people part their cars because they don’t have the money for a Rebuild and the cost/risk of a used 3.4 is high so they don’t know what else to do. So I wanted to tell my story so people consider the option of a 3.2. It’s not for everyone but it certainly works.
The following 11 users liked this post by neilll:
808Bill (05-25-2020),
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details (05-25-2020),
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and 6 others liked this post.
05-25-2020, 02:25 AM
#3
RL Community Team
Rennlist Member
Rennlist Member
Did you drill the head yourself or take it to someone else to do it?
If you did it yourself, any tips?
If you did it yourself, any tips?
05-25-2020, 04:40 AM
#4
I wonder if the 3.4 heads would fit on the 3.2 or wether the valves would be too big and hit the tops of the cylinders, then you could use a 3.2 short motor and everything else would just fit, also another idea I had was as the 2.7 and 3.4 have the same crank etc, I was thinking of leaving my 3.4 in my car for now and build a big bore 3.8 short block from a boxster to then swap over , and still end up with a good 3.4 short motor for spare or to sell on as would be work a lot more as a short motor than a boxster and could re coup some of your build money if you get what I mean. Watch this now boxster short blocks to go through the roof!
05-25-2020, 07:13 AM
#5
My compliments "neilll", an eminently reasonable alternative to replacing a roached 3.4 with a used motor of unknown pedigree. Bravo!
05-25-2020, 10:45 AM
#6
Rennlist Member
Thread Starter
Prelude guy- I remember our messages - glad you found an engine and good luck getting your car on the road.
Tex Squirrel - I did the drilling myself. I used a small drill guide to ensure I was drilling straight. I used a punch to mark locations with the intake runner, then checked locations again, and then started the holes with a dremel to be accurate. I used cutting fluid, checked depth often, and prayed. The tapping was actually pretty easy but again, cutting fluid and go slowly.
Noz - I believe that the heads will fit. But don’t hold me to it.
Thanks Weazer- I thought it a good solution too.
Tex Squirrel - I did the drilling myself. I used a small drill guide to ensure I was drilling straight. I used a punch to mark locations with the intake runner, then checked locations again, and then started the holes with a dremel to be accurate. I used cutting fluid, checked depth often, and prayed. The tapping was actually pretty easy but again, cutting fluid and go slowly.
Noz - I believe that the heads will fit. But don’t hold me to it.
Thanks Weazer- I thought it a good solution too.
The following users liked this post:
Weazer (05-26-2020)
05-25-2020, 11:33 AM
#7
Pretty cool you did this....got you in on a good 911 at low cost. Plus, it looks like you learned a ton. A couple of years ago I was thinking of putting in a 2.7 in a 911 for my son when he was 16. My thinking was it would get him to experience rear engine car without the power😁
Once again nice job and thanks for sharing.
Once again nice job and thanks for sharing.
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05-25-2020, 11:49 AM
#8
Rennlist Member
I researched this swap a few years ago. That's when I ran across Neilll's post.
If I remember correctly, the 3.2L engine is essentially the same as the 3.4L. The heads, block, crank, cams. That's why you only need to drill out some bosses to make it work in a 911. The only difference is the cylinder bore size.
Porsche detuned the 3.2L so it didn't come too close to the 911'a power. With the 996 throttle body and intake related parts, the 3.2L puts out around 270-275 hp.
I'm hoping to test this idea one day. Dyno a properly fitted 3.2L in a 996.
If I remember correctly, the 3.2L engine is essentially the same as the 3.4L. The heads, block, crank, cams. That's why you only need to drill out some bosses to make it work in a 911. The only difference is the cylinder bore size.
Porsche detuned the 3.2L so it didn't come too close to the 911'a power. With the 996 throttle body and intake related parts, the 3.2L puts out around 270-275 hp.
I'm hoping to test this idea one day. Dyno a properly fitted 3.2L in a 996.
05-25-2020, 12:45 PM
#9
Rennlist Member
Hi All
This topic has come up a few times and people seem to talk about it with hushed understanding - you get why someone would cut their losses and spring for 92% of the stock engine but you don’t really want to admit it. Well I’m here to tell you about how I did it and I’m pretty happy.
I got my 2001 Carrera 4 Cabriolet for next to nothing with a blown engine on a sign of goodwill from someone who wanted to see it driven and not stripped for parts; it had just over 125,000. At the time I was working in public service and this was literally the closest I ever imagined myself to living the 911 life. I Even at one point debated between a 2.7 and 3.2 but ultimately a 3.2 with a recent IMS replacement popped up on EBay and I took the plunge for about $3,000 shipped to my door. The engine cost was covered almost exactly by selling the 944 I was driving at the time.
At the time I was pretty set on saving up for a 3.4 after getting whatever engine I got.
After I got the engine i originally ran it with the Boxster intake, fuel lines, and non stock exhaust because I was nervous about having the bosses drilled on the 3.2 head to accept the 3.4 intake and fuel lines. This was a big mistake- I ended up having to alter a lot of stuff to accommodate the Boxster accessories and placement but it was one of those situations where once I realized how much easier(even if a little terrifying) drilling the holes would be it was too late. I got the car running about 4 months after receiving it working on it really occasionally. I had to fix a few things over the last three years but more or less, everything worked without too much drama.
I never tuned the ECU because it ran pretty consistently without triggering any CELs. I averaged around 16.5-17mpg which seemed a little low. But I also mostly drive in the city. The car was really peaky and revved fast up high. Another side effect of not drilling the head is that my exhaust was not fantastic(Boxster headers and first cats to an x pipe style muffler and then exit) it droned super bad around 2,500rpm. I put about 7,500 pretty happy miles on the car in that setup.
More recently I decided to drop the engine and drill the bosses in the head for the intake and exhaust hangers spurred in part by oil leaking from the AOS(pretty sure it was the line that connects now that I pulled it out). I actually just got back from my maiden voyage after doing this work(I also converted to RWD) and took it very easy because I had so much pulled apart and want to take it easy for a bit to listen and feel for loose bolts and such. I will give it a drive or two or three to figure out if it actually feels faster but the math says it should be with the larger intake and exhaust from the 3.4. I long ago sold the original mid pipes/cats from the car because they were coolant and oil soaked when the engine kaboomed for the original owner to a cat recycler. So my car is pretty much everything stock but with the DesignTek 200 cell cats.
So that’s the story of a guy who was too poor(at the time) for even the cheapest 911, making it work with a donor car and a 3.2. Now a days I’ve moved into more lucrative work but still not sure if I’ll end up with another 911. Most likely I will keep an on Caymans(yes, a blaspheme like me would even consider a 4 cylinder) so I have a coupe and a drop top. But first I’m putting my money to other good uses. One thing is almost certain, I am no longer considering the move to a 3.4 - I would consider doing a full on rebuild of an M96 with nikkies and larger pistons but there is no way I’d replace what I have with a stock 3.4; just not enough difference and anecdotally the 3.2 has less chance of failure.
If you have any questions, let me know. I’m sure the car is better with the 3.4 but I also know that it sucks how many people part their cars because they don’t have the money for a Rebuild and the cost/risk of a used 3.4 is high so they don’t know what else to do. So I wanted to tell my story so people consider the option of a 3.2. It’s not for everyone but it certainly works.
This topic has come up a few times and people seem to talk about it with hushed understanding - you get why someone would cut their losses and spring for 92% of the stock engine but you don’t really want to admit it. Well I’m here to tell you about how I did it and I’m pretty happy.
I got my 2001 Carrera 4 Cabriolet for next to nothing with a blown engine on a sign of goodwill from someone who wanted to see it driven and not stripped for parts; it had just over 125,000. At the time I was working in public service and this was literally the closest I ever imagined myself to living the 911 life. I Even at one point debated between a 2.7 and 3.2 but ultimately a 3.2 with a recent IMS replacement popped up on EBay and I took the plunge for about $3,000 shipped to my door. The engine cost was covered almost exactly by selling the 944 I was driving at the time.
At the time I was pretty set on saving up for a 3.4 after getting whatever engine I got.
After I got the engine i originally ran it with the Boxster intake, fuel lines, and non stock exhaust because I was nervous about having the bosses drilled on the 3.2 head to accept the 3.4 intake and fuel lines. This was a big mistake- I ended up having to alter a lot of stuff to accommodate the Boxster accessories and placement but it was one of those situations where once I realized how much easier(even if a little terrifying) drilling the holes would be it was too late. I got the car running about 4 months after receiving it working on it really occasionally. I had to fix a few things over the last three years but more or less, everything worked without too much drama.
I never tuned the ECU because it ran pretty consistently without triggering any CELs. I averaged around 16.5-17mpg which seemed a little low. But I also mostly drive in the city. The car was really peaky and revved fast up high. Another side effect of not drilling the head is that my exhaust was not fantastic(Boxster headers and first cats to an x pipe style muffler and then exit) it droned super bad around 2,500rpm. I put about 7,500 pretty happy miles on the car in that setup.
More recently I decided to drop the engine and drill the bosses in the head for the intake and exhaust hangers spurred in part by oil leaking from the AOS(pretty sure it was the line that connects now that I pulled it out). I actually just got back from my maiden voyage after doing this work(I also converted to RWD) and took it very easy because I had so much pulled apart and want to take it easy for a bit to listen and feel for loose bolts and such. I will give it a drive or two or three to figure out if it actually feels faster but the math says it should be with the larger intake and exhaust from the 3.4. I long ago sold the original mid pipes/cats from the car because they were coolant and oil soaked when the engine kaboomed for the original owner to a cat recycler. So my car is pretty much everything stock but with the DesignTek 200 cell cats.
So that’s the story of a guy who was too poor(at the time) for even the cheapest 911, making it work with a donor car and a 3.2. Now a days I’ve moved into more lucrative work but still not sure if I’ll end up with another 911. Most likely I will keep an on Caymans(yes, a blaspheme like me would even consider a 4 cylinder) so I have a coupe and a drop top. But first I’m putting my money to other good uses. One thing is almost certain, I am no longer considering the move to a 3.4 - I would consider doing a full on rebuild of an M96 with nikkies and larger pistons but there is no way I’d replace what I have with a stock 3.4; just not enough difference and anecdotally the 3.2 has less chance of failure.
If you have any questions, let me know. I’m sure the car is better with the 3.4 but I also know that it sucks how many people part their cars because they don’t have the money for a Rebuild and the cost/risk of a used 3.4 is high so they don’t know what else to do. So I wanted to tell my story so people consider the option of a 3.2. It’s not for everyone but it certainly works.
If you install the 996 intake manifold you will lose some low RPM torque which is the worst thing about most Porsche engines especially if it is a manual trans.
Last edited by Byprodriver; 05-26-2020 at 03:23 PM. Reason: S p
05-26-2020, 11:38 AM
#10
Rennlist Member
Thread Starter
Byprodriver- Just seat of the pants after a couple of drives; I suspect you may be right about low down torque but the dip that the 3.2 has from 3,500-4,500 doesn’t feel as pronounced as it did before; the car pulls more smoothly and consistently from 1,000-5,000 than it did before. So I think in the long run some low down torque loss for possibly a higher peak hp, a little better layout for some things in the engine bay, and some improved drivability is a fair trade off.
Lowpue- thanks, glad you enjoyed!
Lowpue- thanks, glad you enjoyed!
05-26-2020, 01:30 PM
#11
Rennlist Member
Byprodriver- Just seat of the pants after a couple of drives; I suspect you may be right about low down torque but the dip that the 3.2 has from 3,500-4,500 doesn’t feel as pronounced as it did before; the car pulls more smoothly and consistently from 1,000-5,000 than it did before. So I think in the long run some low down torque loss for possibly a higher peak hp, a little better layout for some things in the engine bay, and some improved drivability is a fair trade off.
Lowpue- thanks, glad you enjoyed!
Lowpue- thanks, glad you enjoyed!
You also lose low RPM torque with the smaller engine displacement. Might increase clutch wear.
05-26-2020, 01:42 PM
#12
Rennlist Member
05-26-2020, 03:26 PM
#13
Rennlist Member
05-26-2020, 04:06 PM
#14
Rennlist Member
By that theory, my 240SX would eat through clutches much faster than 996s because it only had a 2.4L.
05-26-2020, 04:12 PM
#15
Rennlist Member
Thread Starter
Having driven a bunch of manual cars; the amount of lost torque from the 3.2 in any configuration is not sufficient to need clutch abuse to get going. It’s very within the noise types of numbers in differences. I’ve found this car to be very easy to get going under all circumstances.
I know people get sensitive about parts being designed for a certain car and motor. But the 3.2 doesn’t have a specifically designed intake and exhaust for its engine- it was literally lifted off of the 2.7. So although generally speaking free flowing intake and exhausts lead to less torque- the 3.4 could very well just be a better better match and not have lost torque. Until someone like me or Preludeguy takes it to a dyno - it’s just conjecture. There are 3.2 boxsters making numbers on the dyno(including torque) close to 3.4s stock from intake, exhaust, and a tune - obviously comparing dyno runs is a bit suspect but you can get a sense of the gains people make.
I know people get sensitive about parts being designed for a certain car and motor. But the 3.2 doesn’t have a specifically designed intake and exhaust for its engine- it was literally lifted off of the 2.7. So although generally speaking free flowing intake and exhausts lead to less torque- the 3.4 could very well just be a better better match and not have lost torque. Until someone like me or Preludeguy takes it to a dyno - it’s just conjecture. There are 3.2 boxsters making numbers on the dyno(including torque) close to 3.4s stock from intake, exhaust, and a tune - obviously comparing dyno runs is a bit suspect but you can get a sense of the gains people make.