Questions about exactlly what is a stroker?
12-06-2015, 05:50 AM
#17
So what is Nikasil?
I just read this great thread re Strokers, including Clarence Carter's take on the subject and realize I know nothing about Nikasil. Can we hear from our experts?
12-06-2015, 12:03 PM
#18
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Rob Edwards forgot to add these links.
http://forums.pelicanparts.com/porsc...tre-928-a.html
https://vimeo.com/6460467
Mike in his white 928 stroker to the right in the video.
Åke
http://forums.pelicanparts.com/porsc...tre-928-a.html
https://vimeo.com/6460467
Mike in his white 928 stroker to the right in the video.
Åke
12-06-2015, 04:15 PM
#19
Rennlist Member
The 928 block is Alusil, with the cylinder bores polished to expose the silicon as a wear surface. Combined with ferrous-coated pistons this works well, but pretty much limited to factory pistons (928 or 968)-- I don't think anyone else has sorted out a coating which works.
Nikasil is a nickle-silicon carbide coating (applied by plating) which opens up other piston choices. There are lots of tradeoffs, it all depends on what the end goal is.
There is a good article on Nikasil on Wikipedia, and also some info on Alusil.
12-06-2015, 05:05 PM
#21
Former Sponsor
Thanks guys. Seems like I have the answer to my question. From one of Greg's threads, he just might have a 5.4 kit lying around somewhere by now. I will check with him. I was just tossing around the cost of SC vs Stroker engines. Alan, I have plenty of engine building experience and have fallen in love with these engines. They seen to be well designed and for what I want it for, (driving the **** out of it every day and sometimes on the track) it is just the thing. I think it just crazy that I would rather have a 928 than any Ferrari I can think of, except maybe a Dino for a while, but for everyday, give me a shark.
What you say Greg, are those kits ready to market yet? I think that thread is dated 2012... Man I got in trouble for spending so much time reading your stroker kit thread. Wife is pissed I am not spending all my time with the grandkids... LOL
What you say Greg, are those kits ready to market yet? I think that thread is dated 2012... Man I got in trouble for spending so much time reading your stroker kit thread. Wife is pissed I am not spending all my time with the grandkids... LOL
A complete stroker "kit" (there is really no such thing, as all of my engines are designed around individual requirements), with crank, rods, pistons, wrist pins, rings, rod bearings, main bearings, head gaskets, block machine work will increase the cost of a rebuild by about 15K-18K (depending on what piston design is chosen....see below).
People generally never add in the cost of a rebuild, when bolting on a supercharger, but it is a bit naive to think adding a bunch of stress to an engine with 100,000+ miles on it is going to work for very long....so this is very unrealistic. Since one needs to buy rings, bearings, etc. to rebuild a stock engine, this reduces the actual additonal cost of building a stroker, when comparing apples with apples.
There's two separate "camps" of the two approaches. A supercharger is a big bolt on thing and is very obvious. A stroker is all internal and can be made to look stock.
Resale on a car with a supercharger is poor....most get removed, in order to sell the car. Even then, because of the added stress that the supercharger puts on the engine, if someone knows that there was a supercharger on it, they will generally go find a different vehicle to purchase. A good stroker increases the value of the car (mine do...not too sure about all the others.)
Stroker engines, done improperly (common in the past/common from other suppliers), were not well designed and used pieces that should have never been used inside a 928 engine. Many of these engines never ran, ran for short periods of time, consumed oil, smoked, etc. The result was that people (for good reasons) became afraid of the results and began looking for other alternatives to increasing power/left their cars stock.
I've perfected these engines to the point where I no longer feel that I have to build them in house, but can supply people with the proper pieces to build them at home......the pieces I make all work together and the assembly is virtually the same as building a stock engine.
What is the difference in the end product?
I think Mark Anderson (owner of 928 International) explained it the best: If you are the kind of person that loves to constantly fuss with your car and enjoys having the hood up everyday, buy a supercharger. If you are the kind of guy that wants to drive your car and only open the hood when it is time to change the oil, build a stroker.
I take it to the next level: If you supercharge your engine, make sure you have the "extended range" AAA towing program. A stroker, sone right, will be as reliable as the stock engine.
To take full advantage of increased displacement, I encourage people to also bore the engines to 104mm, which with a 95.25mm crank, will give you just about 6.5 liters. There are currently two options for this proceedure. The engine can be bored and use 968 pistons on the Alusil surface or the block can be bored, Nicosil coated and use a more generic American piston. There are advantages and disadvantages to either approach and should be discussed on an individual basis. Use of the 968 piston is more expensive.
If you need any further information, please contact me.
Last edited by GregBBRD; 12-06-2015 at 05:48 PM.
12-06-2015, 06:17 PM
#22
Rennlist Member
I wonder if it can be a bolt on affair, if you just have the s4 pistons modified to accept the higher rod angles with the stroker crank, then, ONLY using a custom crank and custom rods to fit the Stock S4 or other pistons. that way, the only cost would be the crank and the rods. Possible? that would get you a 6 litre,
going the full bore" way, you need all greg mentioned.. I think the 968piston is the way to go, as then you use stock Porsche stuff and not much needed to modify the block besides boring. (that is a lot though). Nicasil is a little more of an expense (1-1.5K more) but then you have access to all the custom copy US made 968 sized pistons (like JE, etc) which could save as much as the nickasil process costs.
I have the nicasil stroker and its lasted over 80 race days as it stands today. remarkable engine, no oil burn, and decent power for being mated to all stock Porsche components, right down to the airbox, oiling,breathers, and ECU.
going the full bore" way, you need all greg mentioned.. I think the 968piston is the way to go, as then you use stock Porsche stuff and not much needed to modify the block besides boring. (that is a lot though). Nicasil is a little more of an expense (1-1.5K more) but then you have access to all the custom copy US made 968 sized pistons (like JE, etc) which could save as much as the nickasil process costs.
I have the nicasil stroker and its lasted over 80 race days as it stands today. remarkable engine, no oil burn, and decent power for being mated to all stock Porsche components, right down to the airbox, oiling,breathers, and ECU.
12-06-2015, 06:44 PM
#23
Nordschleife Master
That's just spreading fear, uncertainty, and doubt about supercharging.
Like poorly built stroker is unreliable, so is a poorly built supercharged engine. You can do either one well or poorly. Comparing apples to apples, at a given level of reliability, you'll get more power per dollar from a supercharger than from increasing displacement. What I'm saying here is really not controversial.
Like poorly built stroker is unreliable, so is a poorly built supercharged engine. You can do either one well or poorly. Comparing apples to apples, at a given level of reliability, you'll get more power per dollar from a supercharger than from increasing displacement. What I'm saying here is really not controversial.
A stroker will cost you 3-4 times what a supercharger kit will cost....you are buying expensive internal engine pieces, not just bolting on an overgrown hair dryer.
A complete stroker "kit" (there is really no such thing, as all of my engines are designed around individual requirements), with crank, rods, pistons, wrist pins, rings, rod bearings, main bearings, head gaskets, block machine work will increase the cost of a rebuild by about 15K-18K (depending on what piston design is chosed....see below).
People generally never add in the cost of a rebuild, when bolting on a supercharger, but it is a bit naive to think adding a bunch of stress to an engine with 100,000+ miles on it is going to work for very long....so this is very unrealistic. Since one needs to buy rings, bearings, etc. to rebuild a stock engine, this reduces the actual additonal cost of building a stroker, when comparing apples with apples.
There's two separate "camps" of the two approaches. A supercharger is a big bolt on thing and is very obvious. A stroker is all internal and can be made to look stock.
Resale on a car with a supercharger is poor....most get removed, in order to sell the car. Even then, because of the added stress that the supercharger puts on the engine, if someone knows that there was a supercharger on it, they will generally go find a different vehicle to purchase. A good stroker increases the value of the car (mine do...not too sure about all the others.)
Stroker engines, done improperly (common in the past/common from other suppliers), were not well designed and used pieces that should have never been used inside a 928 engine. Many of these engines never ran, ran for short periods of time, consumed oil, smoked, etc. The result was that people (for good reasons) became afraid of the results and began looking for other alternatives to increasing power/left their cars stock.
I've perfected these engines to the point where I no longer feel that I have to build them in house, but can supply people with the proper pieces to build them at home......the pieces I make all work together and the assembly is virtually the same as building a stock engine.
What is the difference in the end product?
I think Mark Anderson (owner of 928 International) explained it the best: If you are the kind of person that loves to constantly fuss with your car and enjoys having the hood up everyday, buy a supercharger. If you are the kind of guy that wants to drive your car and only open the hood when it is time to change the oil, build a stroker.
I take it to the next level: If you supercharge your engine, make sure you have the "extended range" AAA towing program. A stroker, done right, will be as reliable as the stock engine.
To take full advantage of increased displacement, I encourage people to also bore the engines to 104mm, which with a 95.25mm crank, will give you just about 6.5 liters. There are currently two options for this proceedure. The engine can be bored and use 968 pistons on the Alusil surface or the block can be bored, Nicosil coated and use a more generic American piston. There are advantages and disadvantages to either approach and should be discussed on an individual basis. Use of the 968 piston is more expensive.
If you need any further information, please contact me.
A complete stroker "kit" (there is really no such thing, as all of my engines are designed around individual requirements), with crank, rods, pistons, wrist pins, rings, rod bearings, main bearings, head gaskets, block machine work will increase the cost of a rebuild by about 15K-18K (depending on what piston design is chosed....see below).
People generally never add in the cost of a rebuild, when bolting on a supercharger, but it is a bit naive to think adding a bunch of stress to an engine with 100,000+ miles on it is going to work for very long....so this is very unrealistic. Since one needs to buy rings, bearings, etc. to rebuild a stock engine, this reduces the actual additonal cost of building a stroker, when comparing apples with apples.
There's two separate "camps" of the two approaches. A supercharger is a big bolt on thing and is very obvious. A stroker is all internal and can be made to look stock.
Resale on a car with a supercharger is poor....most get removed, in order to sell the car. Even then, because of the added stress that the supercharger puts on the engine, if someone knows that there was a supercharger on it, they will generally go find a different vehicle to purchase. A good stroker increases the value of the car (mine do...not too sure about all the others.)
Stroker engines, done improperly (common in the past/common from other suppliers), were not well designed and used pieces that should have never been used inside a 928 engine. Many of these engines never ran, ran for short periods of time, consumed oil, smoked, etc. The result was that people (for good reasons) became afraid of the results and began looking for other alternatives to increasing power/left their cars stock.
I've perfected these engines to the point where I no longer feel that I have to build them in house, but can supply people with the proper pieces to build them at home......the pieces I make all work together and the assembly is virtually the same as building a stock engine.
What is the difference in the end product?
I think Mark Anderson (owner of 928 International) explained it the best: If you are the kind of person that loves to constantly fuss with your car and enjoys having the hood up everyday, buy a supercharger. If you are the kind of guy that wants to drive your car and only open the hood when it is time to change the oil, build a stroker.
I take it to the next level: If you supercharge your engine, make sure you have the "extended range" AAA towing program. A stroker, done right, will be as reliable as the stock engine.
To take full advantage of increased displacement, I encourage people to also bore the engines to 104mm, which with a 95.25mm crank, will give you just about 6.5 liters. There are currently two options for this proceedure. The engine can be bored and use 968 pistons on the Alusil surface or the block can be bored, Nicosil coated and use a more generic American piston. There are advantages and disadvantages to either approach and should be discussed on an individual basis. Use of the 968 piston is more expensive.
If you need any further information, please contact me.
12-06-2015, 07:49 PM
#24
Former Sponsor
That's just spreading fear, uncertainty, and doubt about supercharging.
Exactly! The vast majority of the supercharged cars are one partially restricted injector from being parted out by Mark Anderson....one foot in the grave.
Like poorly built stroker is unreliable, so is a poorly built supercharged engine. You can do either one well or poorly. Comparing apples to apples, at a given level of reliability, you'll get more power per dollar from a supercharger than from increasing displacement. What I'm saying here is really not controversial.
While I've had many of my customers "race" their strokers against supercharged cars that "supposedly" make way more horsepower, I'm still not certain any of my clients has ever lost one of these races....
When Hanns was out here, he rode in Rob's mild street stroker and was stunned with the power. Ask him how many supercharged cars he's been in that would drive away from Rob's car.....
The vast majority of these supercharged cars are owned and operated by people that quickly "stand" on the throttle, give it a short blast, and then get off the throttle. Very few would last until they reached "thermal endpoint"....say 3 laps around any race course with a decent driver that had the ability to use full throttle anywhere but in a straight line for a few seconds.
Exactly! The vast majority of the supercharged cars are one partially restricted injector from being parted out by Mark Anderson....one foot in the grave.
Like poorly built stroker is unreliable, so is a poorly built supercharged engine. You can do either one well or poorly. Comparing apples to apples, at a given level of reliability, you'll get more power per dollar from a supercharger than from increasing displacement. What I'm saying here is really not controversial.
While I've had many of my customers "race" their strokers against supercharged cars that "supposedly" make way more horsepower, I'm still not certain any of my clients has ever lost one of these races....
When Hanns was out here, he rode in Rob's mild street stroker and was stunned with the power. Ask him how many supercharged cars he's been in that would drive away from Rob's car.....
The vast majority of these supercharged cars are owned and operated by people that quickly "stand" on the throttle, give it a short blast, and then get off the throttle. Very few would last until they reached "thermal endpoint"....say 3 laps around any race course with a decent driver that had the ability to use full throttle anywhere but in a straight line for a few seconds.
I'm guessing that you've got one hell of a lot more than 5K invested in your boosted car, right?
12-06-2015, 08:56 PM
#26
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Let's not turn this into a N.A. vs. F.I. religious war please.
How many posters on this tread remember the Turbo vs. Supercharger religious war that resulted in many bannings and many otherwise good folks picking up their marbles and going home never to post here again?
How many posters on this tread remember the Turbo vs. Supercharger religious war that resulted in many bannings and many otherwise good folks picking up their marbles and going home never to post here again?
12-06-2015, 10:00 PM
#27
Former Sponsor
I was poking the dog with a stick, through the fence, just a tiny little bit....
I'll contain myself.
12-07-2015, 01:14 AM
#28
Captain Obvious
Super User
Super User
This was a lot more than a tiny bit. It's another if I didn't build it it's ****, post. There are many well build supercharger kits and cars that run them and many of them are on this forum. If Porsche would have built a turbo 928 (there are signs it was gearing up for it in the beginning of the S4), your opinion on a boosted 928 would be different. But since that didn't happen (more likely because of poor sales of the 928), anything but a naturally aspirated 928 is junk in your eyes.
What does it matter if an SC engine will or will not last 3 laps driven by the Stig when the owner never intends to drive it like that? It will last the way the owner drives it and that's more than enough.
What does it matter if an SC engine will or will not last 3 laps driven by the Stig when the owner never intends to drive it like that? It will last the way the owner drives it and that's more than enough.
12-07-2015, 02:12 AM
#29
Rennlist Member
Imo000 and Greg are both right. The type of power the OP is looking for was never discussed yet. He could be a candidate for either. I know my stage one SC engine would thermally overload if I drove it at WOT for any more than a few minutes. It would have huge power during that time but then I would have to back off and let things cool WAY down. Now I can drive it here to California no problem. But I won't be going 180 either.
I have no desire to do so at this time. If I ever change my mind, Greg will be my choice for a stroker. So it's really back to the OP. Do you want to stroke your engine or do you want to SC it?
If so, call Greg and have him help you decide if his strokers are for you or if you should choose a different route.
A bunch of us cutting into each other and going off topic isn't helping the OP
I have no desire to do so at this time. If I ever change my mind, Greg will be my choice for a stroker. So it's really back to the OP. Do you want to stroke your engine or do you want to SC it?
If so, call Greg and have him help you decide if his strokers are for you or if you should choose a different route.
A bunch of us cutting into each other and going off topic isn't helping the OP
12-07-2015, 02:39 AM
#30
Former Sponsor
This was a lot more than a tiny bit. It's another if I didn't build it it's ****, post. There are many well build supercharger kits and cars that run them and many of them are on this forum. If Porsche would have built a turbo 928 (there are signs it was gearing up for it in the beginning of the S4), your opinion on a boosted 928 would be different. But since that didn't happen (more likely because of poor sales of the 928), anything but a naturally aspirated 928 is junk in your eyes.
What does it matter if an SC engine will or will not last 3 laps driven by the Stig when the owner never intends to drive it like that? It will last the way the owner drives it and that's more than enough.
What does it matter if an SC engine will or will not last 3 laps driven by the Stig when the owner never intends to drive it like that? It will last the way the owner drives it and that's more than enough.
How about you find a new hobby other than personally bashing on me on every single chance you get?
Try actually adding something valuable to the other people here....for once!
Take a long look....there's probably six active threads where I'm personally trying to help members fix or understand how to fix their cars.
You're doing that where? You done thst in the last six months? How aboit in the last year? Anything? Anywhere?
No, your status tells it all: "Super user", paying nothing, adding nothing.
"Super troll" would be more correct....maybe we can ask and get your status changed to that.
Does anyone, for even an instant, think that if Porsche would have built a turbo charged version of the 928 that it would have had anywhere near the compression ratio of a naturally aspirated 928?
Not hardly. Anything built, with thst kind of compression would have never made it past the first half hour of the first Porsche dyno test.
And that, alone, is what makes the whole concept such a joke.
Last edited by GregBBRD; 12-07-2015 at 03:09 AM.