Conversion question...
07-20-2002, 02:37 PM
#16
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Roberto, that's what I was wanting. Mainly the 6-spd, and either a 944S2 or 968 engine (now).
Geo, the engine control will not be a problem, already got that taken care of.
There are a lot of things I like about the early cars that the later. For one, I hate the newer dash. Several of my friends have newer 944's and 951's, and I don't like sitting in them staring at the dash. Another is I really don't like electric sunroofs. Mainly, just a lot of petty things that would be considered ridiculous by almost everybody. Not putting down the 951's or anything...just the opposite, trying to be like one in many respects. And I can have the satisfaction of saying, "This is the only Porsche like this that you will probably ever see." because as far as I can tell, no one has t-boed an early 944 because it WOULD be a lot easier to buy a 951, not trying to argue with that. I've always done things with what I had to work with at the time. I had a '62 Ford F-100 truck...two months later, it was completely Chevy powered, from the radiator to the rear-end bolts. I often have an overwhelming desire to do something completely off key. Like I said, not trying to put any other Porsche down for any reason. I just want to keep my car and redo almost all of it.
P.S...got some plans for that "flatter" dash of the early.
Geo, the engine control will not be a problem, already got that taken care of.
There are a lot of things I like about the early cars that the later. For one, I hate the newer dash. Several of my friends have newer 944's and 951's, and I don't like sitting in them staring at the dash. Another is I really don't like electric sunroofs. Mainly, just a lot of petty things that would be considered ridiculous by almost everybody. Not putting down the 951's or anything...just the opposite, trying to be like one in many respects. And I can have the satisfaction of saying, "This is the only Porsche like this that you will probably ever see." because as far as I can tell, no one has t-boed an early 944 because it WOULD be a lot easier to buy a 951, not trying to argue with that. I've always done things with what I had to work with at the time. I had a '62 Ford F-100 truck...two months later, it was completely Chevy powered, from the radiator to the rear-end bolts. I often have an overwhelming desire to do something completely off key. Like I said, not trying to put any other Porsche down for any reason. I just want to keep my car and redo almost all of it.
P.S...got some plans for that "flatter" dash of the early.
07-20-2002, 03:02 PM
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Skip the supercharger. A properly sized turbo will out perform a supercharger any day. The difference in compressor
discharge temps can be 100 degrees F or more. Turbos are significantly more efficient and if they are sized right,
lag will not be an issue.
Not exactly.If you take a stock k-26 turbo and compare it to the supercharger we use, the discharge temps on the small turbo would be
about 125F more then our supercharger! Why? Its simple physics. The smaller the turbo or supercharger, the more heat it generates.Intercooling will alleviate alot of this heat though.
Yes, upgrading the suspension and brakes are a good idea, but not necessary at the time of the conversion. That's
a bunch of hype IMHO.
Its not neccessary but it would probably make the car more stable to drive.When you add close to 100 horsepower at the wheels(like you can with our level 2 supercharger system) you will really be pushing the suspension and brakes to the limits.
You're biggest problem is going to be engine management. Unless you swap in a 951 engine, DME, KLR, and wiring
harness, you don't have a simple solution here (not that replacing the electronics is simple). You will need either
someone who can work with you on a dyno to reprogram your DME or you will need a stand alone and learn how to
program it. For this, you might find a good Japanese car shop. I know that will give people here some severe fits,
but the Japanese car crowd does this all the time and you will probably find someone here who is not only more
willing, but actually probably more experienced with this sort of thing. You'll have to do some homework first
though. There are a lot of monkeys in the Japanese car crowd as well. But by doing some good homework, you
should be able to find someone who really knows what they are doing.
With our supercharger system you retain the stock electronics. You do not need the 951 KLR or DME.The 944 DME works just fine. We do supply you with a piggy back fuel computer and fuel pressure regulator to cover your fueling issues.
If you don't lower the compression ratio you will likely want to hook up an aquamist system. They work wonders
and I have several friends using this and pumping some serious power through turbo'd NA engines in their daily
drivers.
I have to disagree.Our level 2 supercharger system runs about 8 psi(with an intercooler) and it works very well with the stock compression of the 8 valve N/A.It has made 90 extra horsepower and close to 100 ft/lbs of torque at the wheels.This is a substantial increase.The key is fuel control. Without it, this or any other system, would not be as relaible. As far as rice rocket shops knowing what is best goes......Well we are not a rice rocket shop per say (even though we are working on a Skyline GTR at this time) and we do know what works and what doesnt with these Porsches. Take care.
Tim
86 951
<a href="http://www.speedforceracing.com" target="_blank">http://www.speedforceracing.com</a>
619-441-1359
discharge temps can be 100 degrees F or more. Turbos are significantly more efficient and if they are sized right,
lag will not be an issue.
Not exactly.If you take a stock k-26 turbo and compare it to the supercharger we use, the discharge temps on the small turbo would be
about 125F more then our supercharger! Why? Its simple physics. The smaller the turbo or supercharger, the more heat it generates.Intercooling will alleviate alot of this heat though.
Yes, upgrading the suspension and brakes are a good idea, but not necessary at the time of the conversion. That's
a bunch of hype IMHO.
Its not neccessary but it would probably make the car more stable to drive.When you add close to 100 horsepower at the wheels(like you can with our level 2 supercharger system) you will really be pushing the suspension and brakes to the limits.
You're biggest problem is going to be engine management. Unless you swap in a 951 engine, DME, KLR, and wiring
harness, you don't have a simple solution here (not that replacing the electronics is simple). You will need either
someone who can work with you on a dyno to reprogram your DME or you will need a stand alone and learn how to
program it. For this, you might find a good Japanese car shop. I know that will give people here some severe fits,
but the Japanese car crowd does this all the time and you will probably find someone here who is not only more
willing, but actually probably more experienced with this sort of thing. You'll have to do some homework first
though. There are a lot of monkeys in the Japanese car crowd as well. But by doing some good homework, you
should be able to find someone who really knows what they are doing.
With our supercharger system you retain the stock electronics. You do not need the 951 KLR or DME.The 944 DME works just fine. We do supply you with a piggy back fuel computer and fuel pressure regulator to cover your fueling issues.
If you don't lower the compression ratio you will likely want to hook up an aquamist system. They work wonders
and I have several friends using this and pumping some serious power through turbo'd NA engines in their daily
drivers.
I have to disagree.Our level 2 supercharger system runs about 8 psi(with an intercooler) and it works very well with the stock compression of the 8 valve N/A.It has made 90 extra horsepower and close to 100 ft/lbs of torque at the wheels.This is a substantial increase.The key is fuel control. Without it, this or any other system, would not be as relaible. As far as rice rocket shops knowing what is best goes......Well we are not a rice rocket shop per say (even though we are working on a Skyline GTR at this time) and we do know what works and what doesnt with these Porsches. Take care.
Tim
86 951
<a href="http://www.speedforceracing.com" target="_blank">http://www.speedforceracing.com</a>
619-441-1359
07-20-2002, 03:17 PM
#18
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[quote]Originally posted by FSTPRSH:
<strong>And I can have the satisfaction of saying, "This is the only Porsche like this that you will probably ever see." because as far as I can tell, no one has t-boed an early 944 because it WOULD be a lot easier to buy a 951, not trying to argue with that.</strong><hr></blockquote>
Huntley Racing did it for a customer. I think they just put a turbo engine and transmission in, that would be the easiest way IMHO. You are going to have to fabricate your own mounting brackets for the intercooler and such, because the blind nuts are not on your chassie.
<strong>And I can have the satisfaction of saying, "This is the only Porsche like this that you will probably ever see." because as far as I can tell, no one has t-boed an early 944 because it WOULD be a lot easier to buy a 951, not trying to argue with that.</strong><hr></blockquote>
Huntley Racing did it for a customer. I think they just put a turbo engine and transmission in, that would be the easiest way IMHO. You are going to have to fabricate your own mounting brackets for the intercooler and such, because the blind nuts are not on your chassie.
07-20-2002, 03:26 PM
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I've already been looking at the Turbo suspension for when I considered the V8 swap. Minor fabrication won't be much of a problem. I know plenty of metal workers that owe me some favors for computer work. The way I'm looking at it, if I had a 951, I would still be upgrading all suspension compenents necissary (daily driver) and doing most of the things I want to do any way...so this way, the only difference will be the engine and tranny in a sense. Another thing I thought of was (don't shoot me) I want to keep my manual rack-n-pinion. Didn't know if it will bolt up to the newer control arms or not. Any more advice or comments? <--no sarcasm 
The way I'm looking at it, if I had a 951, I would still be upgrading all suspension compenents necissary (daily driver) and doing most of the things I want to do any way...so this way, the only difference will be the engine and tranny in a sense. Another thing I thought of was (don't shoot me) I want to keep my manual rack-n-pinion. Didn't know if it will bolt up to the newer control arms or not. Any more advice or comments? <--no sarcasm
07-20-2002, 03:45 PM
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Sorry for bieng the salesamn of the board lately, but I have almost all parts needed for your conversion. DME, KLR, EXAUST(NO MUFFLER BUT W/WASTEGATE), INTRERCOOLER, INTERCOOLER PIPES, FUSE BOX, COMPELTE WIREING HARNESS, GAUGE CLUSTER, HEADERS, DOWNPIPE, AND WHATEVER ELSE YOU NEED.
07-20-2002, 04:42 PM
#22
Race Director
[quote]Originally posted by TurboTim:
<strong>Not exactly.If you take a stock k-26 turbo and compare it to the supercharger we use, the discharge temps on the small turbo would be
about 125F more then our supercharger! Why? Its simple physics. The smaller the turbo or supercharger, the more heat it generates.Intercooling will alleviate alot of this heat though.
</strong><hr></blockquote>
I did say a properly sized turbo. Boost for boost a properly sized turbo will have significantly lower compressor discharge temps than a properly sized supercharger. That is simple physics. Turbos are more efficient that superchargers. The key is in the sizing.
[quote]Originally posted by TurboTim:
<strong>With our supercharger system you retain the stock electronics. You do not need the 951 KLR or DME.The 944 DME works just fine. We do supply you with a piggy back fuel computer and fuel pressure regulator to cover your fueling issues.
</strong><hr></blockquote>
No reason this cannot be done for a turbo.
[quote]Originally posted by TurboTim:
<strong>I have to disagree.Our level 2 supercharger system runs about 8 psi(with an intercooler) and it works very well with the stock compression of the 8 valve N/A.</strong><hr></blockquote>
Well, there we go. No reason you cannot turbocharge a NA 944. Again, the compressor discharge temps of a properly sized turob will be lower than a supercharger. I know it's a bit lame not to have them already, but I'll find the calculations and post them. A good friend is an engineer for Garrett (he also works with superchargers in his work) and he posted the calculations to the SE-R mailing list. I'm having trouble finding them, but I'll get them and post them.
[quote]Originally posted by TurboTim:
<strong>The key is fuel control. </strong><hr></blockquote>
Right. Basically what I said in my first post. I would think the spark mapping would be critical as well.
[quote]Originally posted by TurboTim:
<strong>As far as rice rocket shops knowing what is best goes......</strong><hr></blockquote>
Tim, please don't misunderstand me. I don't think the Japanese car shops know any better. I don't think I implied that and if I did I apologize and state that they don't. What I think I did say and intended to say is that they do this stuff all the time. There is an attitude in Porsche circles that this cannot be done. I don't think you would get that sort of predisposition from a Japanese car shop. Some might say it's because they don't know Porsches, but that's BS. It's because they won't be hampered by the preconceptions of the Porsche community. There is a preconception here that it cannot be done. We both know that's not true.
[quote]Originally posted by TurboTim:
<strong>Well we are not a rice rocket shop per say (even though we are working on a Skyline GTR at this time) and we do know what works and what doesnt with these Porsches. Take care. </strong><hr></blockquote>
Too cool Tim. Is it an R32, R33, or R34?
<strong>Not exactly.If you take a stock k-26 turbo and compare it to the supercharger we use, the discharge temps on the small turbo would be
about 125F more then our supercharger! Why? Its simple physics. The smaller the turbo or supercharger, the more heat it generates.Intercooling will alleviate alot of this heat though.
</strong><hr></blockquote>
I did say a properly sized turbo. Boost for boost a properly sized turbo will have significantly lower compressor discharge temps than a properly sized supercharger. That is simple physics. Turbos are more efficient that superchargers. The key is in the sizing.
[quote]Originally posted by TurboTim:
<strong>With our supercharger system you retain the stock electronics. You do not need the 951 KLR or DME.The 944 DME works just fine. We do supply you with a piggy back fuel computer and fuel pressure regulator to cover your fueling issues.
</strong><hr></blockquote>
No reason this cannot be done for a turbo.
[quote]Originally posted by TurboTim:
<strong>I have to disagree.Our level 2 supercharger system runs about 8 psi(with an intercooler) and it works very well with the stock compression of the 8 valve N/A.</strong><hr></blockquote>
Well, there we go. No reason you cannot turbocharge a NA 944. Again, the compressor discharge temps of a properly sized turob will be lower than a supercharger. I know it's a bit lame not to have them already, but I'll find the calculations and post them. A good friend is an engineer for Garrett (he also works with superchargers in his work) and he posted the calculations to the SE-R mailing list. I'm having trouble finding them, but I'll get them and post them.
[quote]Originally posted by TurboTim:
<strong>The key is fuel control. </strong><hr></blockquote>
Right. Basically what I said in my first post. I would think the spark mapping would be critical as well.
[quote]Originally posted by TurboTim:
<strong>As far as rice rocket shops knowing what is best goes......</strong><hr></blockquote>
Tim, please don't misunderstand me. I don't think the Japanese car shops know any better. I don't think I implied that and if I did I apologize and state that they don't. What I think I did say and intended to say is that they do this stuff all the time. There is an attitude in Porsche circles that this cannot be done. I don't think you would get that sort of predisposition from a Japanese car shop. Some might say it's because they don't know Porsches, but that's BS. It's because they won't be hampered by the preconceptions of the Porsche community. There is a preconception here that it cannot be done. We both know that's not true.
[quote]Originally posted by TurboTim:
<strong>Well we are not a rice rocket shop per say (even though we are working on a Skyline GTR at this time) and we do know what works and what doesnt with these Porsches. Take care. </strong><hr></blockquote>
Too cool Tim. Is it an R32, R33, or R34?
07-20-2002, 04:54 PM
#23
Race Director
[quote]Originally posted by FSTPRSH:
<strong>Geo, the engine control will not be a problem, already got that taken care of.</strong><hr></blockquote>
Then you have one of the two hardest part already figured out. The other is turbo sizing which is critical. See Mike Kojima's article in Sport Compact Car (Sept 2001) for how to properly size a turbo. He also wrote an article for the July 2002 issue that gives a guide w/o the math. Do yourself a favor and get the Sept 2001 issue.
IMHO a good shop should be able to package a turbo set-up better than the 951 - no crossovers and such.
I think the first person/shop to work out a solution is going to get a lot of questions/business.
<strong>Geo, the engine control will not be a problem, already got that taken care of.</strong><hr></blockquote>
Then you have one of the two hardest part already figured out. The other is turbo sizing which is critical. See Mike Kojima's article in Sport Compact Car (Sept 2001) for how to properly size a turbo. He also wrote an article for the July 2002 issue that gives a guide w/o the math. Do yourself a favor and get the Sept 2001 issue.
IMHO a good shop should be able to package a turbo set-up better than the 951 - no crossovers and such.
I think the first person/shop to work out a solution is going to get a lot of questions/business.
07-20-2002, 07:35 PM
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I'm gonna have to go with Geo here. I've seen a lot of blowers (superchargers) and have yet to see one that doesn't require a bigger cam to get back the horsepower it took away. Ian, a friend of mine, had a blown Olds 442 that was "making" 780 HP at 7000 RPM. I got the specs from him on the engine, ran the math, he was making 605 HP at 6400 and that was at the flywheel. His main problem was running such a high overdrive, the engine had to work harder to turn the rotors in the blower case, on top of it already being a hard device to turn (think HUGE A/C compressor). Could someone give me more info on sizing the turbo? I want the system to be as non-cpmplex as possible yet make moderately high, reliable power. What all does the process involve...HP, Tq, cam, etc? Thanks for all the help so far guys.
Could someone give me more info on sizing the turbo? I want the system to be as non-cpmplex as possible yet make moderately high, reliable power. What all does the process involve...HP, Tq, cam, etc? Thanks for all the help so far guys.
07-20-2002, 08:26 PM
#25
Race Director
[quote]Originally posted by FSTPRSH:
<strong>Could someone give me more info on sizing the turbo? I want the system to be as non-cpmplex as possible yet make moderately high, reliable power. What all does the process involve...HP, Tq, cam, etc?</strong><hr></blockquote>
The absolute key to max power and minimal lag is in the sizing. I highly recommend the articles I mentioned by Mike Kojima. Mike is an engineer for an OEM, a consultant to the aftermarket performance industry, a racer, and he used to be involved with the TRD IMSA race engine program. The hardest part about sizing a turbo is to get a hold of the compressor maps. But the details do make a difference.
<strong>Could someone give me more info on sizing the turbo? I want the system to be as non-cpmplex as possible yet make moderately high, reliable power. What all does the process involve...HP, Tq, cam, etc?</strong><hr></blockquote>
The absolute key to max power and minimal lag is in the sizing. I highly recommend the articles I mentioned by Mike Kojima. Mike is an engineer for an OEM, a consultant to the aftermarket performance industry, a racer, and he used to be involved with the TRD IMSA race engine program. The hardest part about sizing a turbo is to get a hold of the compressor maps.
But the details do make a difference.
07-20-2002, 11:00 PM
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Mistubishi turbos are apparently the fastest spooling turbos (just the opinion of a friend of mine who owns an import shop and does a lot of turbo applications) but do not flow as well as turbonetics turbos for the size. If you are interested in drivability, a mistsubishi 16G might not be a bad choice...I don't know if they have them in different trims that would be suited to your motor though. I would opt not to get any of the KKK turbos that were originally used on older porsches (K26, K27, K29, etc.) because they are a very old design and have been far surpassed in materials and compressor/turbine design by other companies. For an n/a motor, without lowering compression, you are going to hit a HP ceiling for which you can run on pump gas...probably 300 or so. Lowering compression (you could just buy used 951 pistons and rods if your cylinder bores are relatively unmolested, and install new rings...you are also going to want to at least install a wide fire head gasket...maybe get your head refreshed while it is off...) will gain you more headroom for which you can forcefeed your motor air running on pump gas without detonation. Any brand of turbo will work, you just have to have the flanges on your piping mated to the flanges on your turbo, which any exhaust shop should be able to do for you.
Fueling shouldn't be much of a problem if you have a stand alone fuel/spark computer. You can buy used 951 injectors for cheap (I think turbotim has a bunch of old ones for sale on his website...he also has 951 pistons and rods listed on the site, too...here is the link to his used parts page: <a href="http://www.speedforceracing.com/partsforsale.html" target="_blank">http://www.speedforceracing.com/partsforsale.html</a> ) and unless you are running over 330 someodd HP these should be able to provide your engine's needs for fuel. I don't think these injectors work with the 944 n/a DME though...different impedence or something. Sounds like an interesting project...keep us updated.
Fueling shouldn't be much of a problem if you have a stand alone fuel/spark computer. You can buy used 951 injectors for cheap (I think turbotim has a bunch of old ones for sale on his website...he also has 951 pistons and rods listed on the site, too...here is the link to his used parts page: <a href="http://www.speedforceracing.com/partsforsale.html" target="_blank">http://www.speedforceracing.com/partsforsale.html</a> ) and unless you are running over 330 someodd HP these should be able to provide your engine's needs for fuel. I don't think these injectors work with the 944 n/a DME though...different impedence or something. Sounds like an interesting project...keep us updated.
07-20-2002, 11:12 PM
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Oh yeah...definitely intercool the turbo. The stock 951 intercooler would do a fine job unless you are trying to build a monster of a motor. On the same link I gave above there is a stock 951 intercooler for sale, and it is more or less a bolt in (you would just need to make a bracket and drill a couple of holes, but it is made to fit in your nose panel, so not much fabbing would be necessary).
So...If I was you, this would be my shopping list:
Turbocharger (unknown as of now...depending on how wild you plan on going...T3/T4 hybrid, 16G, T04E, T66...how much power are you trying to make and how much building of the motor are you trying to do?)
Stock 951 intercooler
4 Stock 951 injectors (get them cleaned and balanced before installing them)
4 Stock 951 pistons/rods
piston ring set
wide fire headgasket and/or o-ringed head and/or 5 angle grind, P&P, etc. head job
tial/deltagate wastegate
some sort of BOV (greddy?)
lots of stainless mandrel bent tubing and friend who can weld
open exhaust
Fuel/Spark computer with sensors
a stock 951 intake manifold wouldn't hurt since it would bolt right up and probably flows better than the 944 intake
Put all of that in, get it to work, then worry about brakes and suspension
Good luck
So...If I was you, this would be my shopping list:
Turbocharger (unknown as of now...depending on how wild you plan on going...T3/T4 hybrid, 16G, T04E, T66...how much power are you trying to make and how much building of the motor are you trying to do?)
Stock 951 intercooler
4 Stock 951 injectors (get them cleaned and balanced before installing them)
4 Stock 951 pistons/rods
piston ring set
wide fire headgasket and/or o-ringed head and/or 5 angle grind, P&P, etc. head job
tial/deltagate wastegate
some sort of BOV (greddy?)
lots of stainless mandrel bent tubing and friend who can weld
open exhaust
Fuel/Spark computer with sensors
a stock 951 intake manifold wouldn't hurt since it would bolt right up and probably flows better than the 944 intake
Put all of that in, get it to work, then worry about brakes and suspension
Good luck
07-20-2002, 11:20 PM
#29
Race Director
"Originally posted by TurboTim:
I have to disagree.Our level 2 supercharger system runs about 8 psi(with an intercooler) and it works very well with the stock compression of the 8 valve N/A.
------------------------------------------------------------------------
George: Well, there we go. No reason you cannot turbocharge a NA 944. Again, the compressor discharge temps of a properly sized turob will be lower than a supercharger. I know it's a bit lame not to have them already, but I'll find the calculations and post them. A good friend is an engineer for Garrett (he also works with superchargers in his work) and he posted the calculations to the SE-R mailing list. I'm having trouble finding them, but I'll get them and post them."
Another way to look at it is to reduce the number of variables. Let's say you 'properly size' BOTH a turbo and a supercharger so that they BOTH have the same efficiency (temperature rise) and the SAME boost, say 8psi, the turbo will ALWAYS generate MORE power than the supercharger for the same level of boost. Why? Because the supercharger is sucking up engine-power to drive itself. So to generate the SAME power increase as a turbo, the supercharger has to use more boost.
On some of the early supercharged Formula-1 cars, over 150hp of the engine's output went to running the supercharger. No wonder they eventually went exclusively to turbos later on. Renault pioneered the effort and Porsche did quite well in the second-generation, until Honda dominated the later stages. The Turbos were eventually outlawed because they were too powerful (and costly). Driving a 1500-1800bhp car had to be insanely scary.
I have to disagree.Our level 2 supercharger system runs about 8 psi(with an intercooler) and it works very well with the stock compression of the 8 valve N/A.
------------------------------------------------------------------------
George: Well, there we go. No reason you cannot turbocharge a NA 944. Again, the compressor discharge temps of a properly sized turob will be lower than a supercharger. I know it's a bit lame not to have them already, but I'll find the calculations and post them. A good friend is an engineer for Garrett (he also works with superchargers in his work) and he posted the calculations to the SE-R mailing list. I'm having trouble finding them, but I'll get them and post them."
Another way to look at it is to reduce the number of variables. Let's say you 'properly size' BOTH a turbo and a supercharger so that they BOTH have the same efficiency (temperature rise) and the SAME boost, say 8psi, the turbo will ALWAYS generate MORE power than the supercharger for the same level of boost. Why? Because the supercharger is sucking up engine-power to drive itself. So to generate the SAME power increase as a turbo, the supercharger has to use more boost.
On some of the early supercharged Formula-1 cars, over 150hp of the engine's output went to running the supercharger. No wonder they eventually went exclusively to turbos later on. Renault pioneered the effort and Porsche did quite well in the second-generation, until Honda dominated the later stages. The Turbos were eventually outlawed because they were too powerful (and costly). Driving a 1500-1800bhp car had to be insanely scary.
07-21-2002, 01:10 AM
#30
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We have done a 944S2 Supercharger conversion, and we are doing a 968 Turbo conversion. We own a 944 (1983) race car that we are building a 3.1 liter engine NA that will show on the low side 220 at the tires.
I've been doing these kind of conversions and kits for a while...in order of ease, I'll list my experience.
944 8 valve Supercharger, bolt in on and run...pretty simple, the lower end is a mule, the compression is easy to deal with. When I was Tim's partner at SFR, we bolted a Supercharger to the NA and basically just ran the crap out of it on the dyno, never detonated, just showed great numbers, no blow by or any signs of potential problems to the bottom end.
968 turbo conversion, by far the easiest mod we have done, bolt in the parts, run 951 this and that...bam, 60 hp at the wheels improvement, no detonation.
944S2/968 Supercaherger conversion, issues, but not something that cannot be completed by a good shop. Many upgrades to the induction, 993 type MAF sensor, custom wiring, custom chips.
Turbo engine swap, not that tough, but more expensive than the other mods, given the labor charges and the engine charge, let alone any freshing up on the old 951 motor your installing.
My money would go first to a simple and reliable turbo conversion to your existing motor, then second, a SC kit.
THe brakes and suspension folk will now enter and explain the expensive mods you need to handle that HP gain, but we are running stock brakes on our race car, with a 3.1 liter NA engine, 13:1 compression cam etc...no plans to change the system.
Thats my input :-)
I've been doing these kind of conversions and kits for a while...in order of ease, I'll list my experience.
944 8 valve Supercharger, bolt in on and run...pretty simple, the lower end is a mule, the compression is easy to deal with. When I was Tim's partner at SFR, we bolted a Supercharger to the NA and basically just ran the crap out of it on the dyno, never detonated, just showed great numbers, no blow by or any signs of potential problems to the bottom end.
968 turbo conversion, by far the easiest mod we have done, bolt in the parts, run 951 this and that...bam, 60 hp at the wheels improvement, no detonation.
944S2/968 Supercaherger conversion, issues, but not something that cannot be completed by a good shop. Many upgrades to the induction, 993 type MAF sensor, custom wiring, custom chips.
Turbo engine swap, not that tough, but more expensive than the other mods, given the labor charges and the engine charge, let alone any freshing up on the old 951 motor your installing.
My money would go first to a simple and reliable turbo conversion to your existing motor, then second, a SC kit.
THe brakes and suspension folk will now enter and explain the expensive mods you need to handle that HP gain, but we are running stock brakes on our race car, with a 3.1 liter NA engine, 13:1 compression cam etc...no plans to change the system.
Thats my input :-)