porsche vs. rx7 and supra
08-28-2002, 08:31 PM
#16
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RX7 engines are solid as long no one turns the powerscrew or overevs more then usefull.
I love that one: We even opened up the intake and exhaust ports for more flow. Broke it in nice and easy. It blew up anyway!
Nice idear, but it hurts the "coating" and thats why it didn´t worked.
Grüsse
man, what are you talking about? If it hurts the "coating" then that engine shouldn't be in a car! It's unreliable and that's it. If you can't port an engine on your car without worrying it'll blow up, then there's something wrong. What would you know about a rotary engine anyway. My cousin and I put that engine together with our eyes closed. The fact of the matter is, if every time you go to turn the key and you're afraid, thinking something else will go wrong, then it's not worth having anymore. You can't enjoy it.
RX7 engines are solid as long no one turns the powerscrew or overevs more then usefull.
I love that one: We even opened up the intake and exhaust ports for more flow. Broke it in nice and easy. It blew up anyway!
Nice idear, but it hurts the "coating" and thats why it didn´t worked.
Grüsse
man, what are you talking about? If it hurts the "coating" then that engine shouldn't be in a car! It's unreliable and that's it. If you can't port an engine on your car without worrying it'll blow up, then there's something wrong. What would you know about a rotary engine anyway. My cousin and I put that engine together with our eyes closed. The fact of the matter is, if every time you go to turn the key and you're afraid, thinking something else will go wrong, then it's not worth having anymore. You can't enjoy it.
08-29-2002, 01:28 AM
#17
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Sorry silver I must agree with Roland. I have 2 Rx-7's a 91 and 93 both have been really reliable and as far as Im concerned great cars and extremely fast. The rotary engine is trully a reliable and amazing engine. Most people just buy an rx-7 and try to add tons of horsepower instead of enjoying the tremendous power it has. In my opinion if you wanna tinker with your engine BUY A CIVIC! It is sad that you dont like it and have had bad luck with it.
08-29-2002, 10:20 PM
#18
Three Wheelin'
Porscheluv,
I think you're just a lucky guy. Everyone I know with final gen RX-7's is just like Silver stated - scared to drive their cars.
Check out the reviews on carreview.com sometime... plenty of things like: "I had Mazda install a new engine under warranty... it lasted 30k at least..."
Pretty sad stuff there. I agree with comments about the 1st and 2nd gens though... great little cars.
Micah
I think you're just a lucky guy. Everyone I know with final gen RX-7's is just like Silver stated - scared to drive their cars.
Check out the reviews on carreview.com sometime... plenty of things like: "I had Mazda install a new engine under warranty... it lasted 30k at least..."
Pretty sad stuff there. I agree with comments about the 1st and 2nd gens though... great little cars.
Micah
08-30-2002, 12:38 PM
#19
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@Silverbullet951
man, what are you talking about?
Sorry no first (own) hand exp. on Mazda rotarys.
( I worked on Ro 80 rotarys and those are far more advanced full aluminum engines runing on Nikasil surfaces )
But I know the B13 on rotarys have nitratet surfaces and a special surface treatment called Blanchard process ( SP ? Think written like the watch manufactorer ).
One scratch or a soft spot and the sealing will scarf into the metall and start grinding.....
If you know rotarys you sure can explain me/us some deatils
If it hurts the "coating" then that engine shouldn't be in a car! It's unreliable and that's it. If you can't port an engine on your car without worrying it'll blow up, then there's something wrong.
That coating is the base that that engine is usable in a car. It´s the base for reliability.
Mazda wasn´t thinking to sale a car to people who go to port them. They would have done the job themself saleing a tuning stage if they didn´t feared problems ( Your @ss get smashed bad by costumers when the engine doesn´t work as descriped or blows up even under missuse, so the conesquence is you must produce fullproof ( or Foolproof ? ) engines even for the dumpest user. )
What would you know about a rotary engine anyway.
Nothing compared to a rotary expert. ( but enough to talk with engine builders and engeneers about technical stuff and even to become Tech Advisor on rennlist )
I would never try to "improve" a rotary as it is just to much engeneered to be improved by simple grinding jobs. If you start improving a engine you have to invest time and money and your first engines will show errors to correct on the next one.
Same applies also to Porsche engines.
A woundefull example is that I ( the company I work for ) built Porsche 356 engines that have 120 HP on the brake.
Most people think we ask for to much money and buy the same parts like we use in our engine and they rarly can get more then 110 HP squished out and most from them will not last half the time like our engines does. ( mostly as they race in the same class and try to keep up so they have to push the engines more.... )
The difference between the engines are some 100 manhour finetuning and the input from some old 356 engine builders ( there 30 years expirience on the subject )
My cousin and I put that engine together with our eyes closed.
Maybe that was the reason ?
If you work on engines you double check and messure twice. If you start tuning them you have to reasearch everything twice from two different persons. The facts are then what both show up and the questinable need further reasearch or own testing.
The fact of the matter is, if every time you go to turn the key and you're afraid, thinking something else will go wrong, then it's not worth having anymore. You can't enjoy it.
Thats a matter from they guy who built the engine.
If mazda can built a reliable turnkey rotary I also would trust other people to rebuild that engine in the same way. ( as long those guys keep there eyes open and don´t dream while working )
I also would trust mechanics "opening" up a rotary if they proof there knowledge by giving waranty and stand behind there products.
I would never except a tuned rotary would work as good as a stock unit despite as long
You know no free lunch, if you push for more power you have to give up something else. its on you what you will trade in.
Grüsse
@Silverbullet951
man, what are you talking about?
Sorry no first (own) hand exp. on Mazda rotarys.
( I worked on Ro 80 rotarys and those are far more advanced full aluminum engines runing on Nikasil surfaces )
But I know the B13 on rotarys have nitratet surfaces and a special surface treatment called Blanchard process ( SP ? Think written like the watch manufactorer ).
One scratch or a soft spot and the sealing will scarf into the metall and start grinding.....
If you know rotarys you sure can explain me/us some deatils
If it hurts the "coating" then that engine shouldn't be in a car! It's unreliable and that's it. If you can't port an engine on your car without worrying it'll blow up, then there's something wrong.
That coating is the base that that engine is usable in a car. It´s the base for reliability.
Mazda wasn´t thinking to sale a car to people who go to port them. They would have done the job themself saleing a tuning stage if they didn´t feared problems ( Your @ss get smashed bad by costumers when the engine doesn´t work as descriped or blows up even under missuse, so the conesquence is you must produce fullproof ( or Foolproof ? ) engines even for the dumpest user. )
What would you know about a rotary engine anyway.
Nothing compared to a rotary expert. ( but enough to talk with engine builders and engeneers about technical stuff and even to become Tech Advisor on rennlist
) I would never try to "improve" a rotary as it is just to much engeneered to be improved by simple grinding jobs. If you start improving a engine you have to invest time and money and your first engines will show errors to correct on the next one.
Same applies also to Porsche engines.
A woundefull example is that I ( the company I work for ) built Porsche 356 engines that have 120 HP on the brake.
Most people think we ask for to much money and buy the same parts like we use in our engine and they rarly can get more then 110 HP squished out and most from them will not last half the time like our engines does. ( mostly as they race in the same class and try to keep up so they have to push the engines more.... )
The difference between the engines are some 100 manhour finetuning and the input from some old 356 engine builders ( there 30 years expirience on the subject )
My cousin and I put that engine together with our eyes closed.
Maybe that was the reason ?
If you work on engines you double check and messure twice. If you start tuning them you have to reasearch everything twice from two different persons. The facts are then what both show up and the questinable need further reasearch or own testing.
The fact of the matter is, if every time you go to turn the key and you're afraid, thinking something else will go wrong, then it's not worth having anymore. You can't enjoy it.
Thats a matter from they guy who built the engine.
If mazda can built a reliable turnkey rotary I also would trust other people to rebuild that engine in the same way. ( as long those guys keep there eyes open and don´t dream while working )
I also would trust mechanics "opening" up a rotary if they proof there knowledge by giving waranty and stand behind there products.
I would never except a tuned rotary would work as good as a stock unit despite as long
You know no free lunch, if you push for more power you have to give up something else. its on you what you will trade in.
Grüsse
08-30-2002, 05:56 PM
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That's the point. The engine is at the limit. It is an extreme design that makes lots of power out of such a small compartment, and double the heat of a regular piston engine. It can be modified and I have seen and know people who make 700 to 800 hp out of a turbocharged rotary engine. They only last about 24 hours, but that's the point. they can make extreme power, but they don't last. all I'm saying is, If you want more power out of your car, make sure it's not a turbocharged rx-7.
08-31-2002, 09:49 PM
#21
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That's the point. The engine is at the limit.
Every engine is on a "limit". Everyone tuning a engine streches the limit.
The point is you can´t argue the RX is bad car becourse the engine isn´t capable to be tuned by ashade tree mechanics to higher performance.
BTW, if you port the exhaustside from a 951 engine or a 993TT you also run in slight problems.
The main problem with the rotary engines is that they need a complete other driving style compared to a normal piston engine. That is hard to explain to costumers who just want to floor the pedal and dust other people on the straigt.
Mercedes made all the engeneering for superb Wankel engines ( the later versions had 700 Hp from a little & light package )in the 70´s and stoped the project for several reasons.
One was that they where thinking about replacing there V8 with a 4 disc rotary but they knew if people would use the engines like a V8 engine they would run into the same problems that the NSU R80 had. Then the FIA made a "bad move" on homologation so you couldn´t race a rotary ( that killed the C 111 project ). The new emison laws wheren´t a real problem for the direct injectet Mercedes but the high fuel consumption on part laod and the oil crisis with droping sales numbers....
Fact is the rotary engines are made for people who love that engine and know how to use it.
Then those engines get very old.
If you learned to drive a modern piston engine and got used to that you have to "relearn".
A good practicing engine for a rotary is a 911 2,0 S or Ferrari Dino engine
Rotarys don´t like full load at low revs, cold starts and high revs and said overreving.
The same problems had the piston engine in the first 50 years and some rotary developments made todays piston engine performance possible.
Other Mazda problems are that there typical workforce on the dealers aren´t capable working with complex cars and some from them just dislike the rotary. A typical Mazda maintaince was washing the car, change the oil and spark plugs and look trough the car.
They never needed to troubleshoot much or needed to adjust a engine.
In germany Mazda knew that problem and they had traveling techs for there rotarys.
In germany RX7 where sold to people who love the rotary and in germany you use a sportcar a bit different.
I think some 300 units where sold in the 3 years mazda offered the RX7 3gen here.
I heard that the first cars had many qualityproblems in the interiour and some electric problems ( german cars must have a dead look theft protection and those units made trouble ). Some engines had failures mostly covered under waranty but as I heard it most had been just overreved or overchiped.
It is an extreme design that makes lots of power out of such a small compartment, and double the heat of a regular piston engine.
Its just a other engine design with own strenghts and foults.
The rotary is between the piston engine and the turbines. ( remember turbines used in cars ? check the US car history ).
Did you know that the first rotary prototype in 1957 made 30 HP @ 18000 min from just 250 cc. Thats some 120 HP/Liter.
Imagen in 1957 a typical piston engine produced some 25 HP/L and high performance engines where at 50 HP/L.
But the first rotarys didn´t run very long as the spark plug technology only alowed several hours dutytime. And on the first rotarys the sparkplug was siting inside the inner tromboide that was the stator and the outer ring was runing around it.
On the heat problem; that isn´t a real problem for a good engeneer.
But the rotarys need a hot exhaustside and a tuned system ( like two strokes ) to run efficient ( achive high MPG rates ).
It can be modified and I have seen and know people who make 700 to 800 hp out of a turbocharged rotary engine. They only last about 24 hours, but that's the point. they can make extreme power, but they don't last.
What is your point ? some peole built engines with much more power to last for 6 secounds full load.
I´m not sure if a actuall formula 1 engine will last 24 hours
Hell if you need a engine to work 24 hours with total power no one will care if it falls apart in the 25th hour, even worser if it don´t fall apart in the 25th hour you did something wrong and know you could squish out more power are save some wight.
A typicall Formula 2/3000 Ford V8 Cosworth ( 3,0 600 HP ) runs 20-30 Hours and then the powerloos or the risk to break something forces to a partial rebuild. The typical rebuild costs are some 10 000 $. If you overrev or make a other stupid mistake you easily blow 30 000 $ away.
One from my friends worked as a engine mechanic at the Top fueler class. They made a fast "recheck" between the runs. Normaly they only reneweed the head gasket and checked the pistons but sometimes they swaped the complete piston with rod between the runs and replaced the heads. In the 80´s those parts could buy a new Alto or Yugo.
But hell those V8´s pumped over 3000 HP on the wheels.
The question is what are your goals and what will/can you afford to achive that.
all I'm saying is, If you want more power out of your car, make sure it's not a turbocharged rx-7.
Yeah just buy a 400 HP Corvette or a Viper and blow that Mazda away. And if you can´t do it then you can turbocharge that old iron for a handfull dollars and they will never break and drive 100 000 miles without even touching the engine
If you drive a 951 and your car is in good shape then just go down on any racetrack and compare how good the car is in a typical street car field.
You will be surprised that driving fast isn´t relatet to engine power and you will be surprised that "underpowered" cars outperform most Supercars.
The thing is if you have 100000 $ to spent for a car what car what will you do, shop a 996 TT witch is factory stock out from the box reliable full waranty leader from the pack or invest the same money into a RX7 and ask Rod Millen for some good parts. I´m sure the same money in a RX7 will push the performance far beyound the 996 tT. But the next things are.
Are you capable using that power ?
Is the reliability similar and the car able to do daily stop&go and the little missuses we all do for our lazyness ?
How will people react if you spend "that" money into a RX7 and not buying a 996 TT ?
And if you decide to sale that car how much from your investment can be recouped on the marked ?
Grüsse
That's the point. The engine is at the limit.
Every engine is on a "limit". Everyone tuning a engine streches the limit.
The point is you can´t argue the RX is bad car becourse the engine isn´t capable to be tuned by ashade tree mechanics to higher performance.
BTW, if you port the exhaustside from a 951 engine or a 993TT you also run in slight problems.
The main problem with the rotary engines is that they need a complete other driving style compared to a normal piston engine. That is hard to explain to costumers who just want to floor the pedal and dust other people on the straigt.
Mercedes made all the engeneering for superb Wankel engines ( the later versions had 700 Hp from a little & light package )in the 70´s and stoped the project for several reasons.
One was that they where thinking about replacing there V8 with a 4 disc rotary but they knew if people would use the engines like a V8 engine they would run into the same problems that the NSU R80 had. Then the FIA made a "bad move" on homologation so you couldn´t race a rotary ( that killed the C 111 project ). The new emison laws wheren´t a real problem for the direct injectet Mercedes but the high fuel consumption on part laod and the oil crisis with droping sales numbers....
Fact is the rotary engines are made for people who love that engine and know how to use it.
Then those engines get very old.
If you learned to drive a modern piston engine and got used to that you have to "relearn".
A good practicing engine for a rotary is a 911 2,0 S or Ferrari Dino engine
Rotarys don´t like full load at low revs, cold starts and high revs and said overreving.
The same problems had the piston engine in the first 50 years and some rotary developments made todays piston engine performance possible.
Other Mazda problems are that there typical workforce on the dealers aren´t capable working with complex cars and some from them just dislike the rotary. A typical Mazda maintaince was washing the car, change the oil and spark plugs and look trough the car.
They never needed to troubleshoot much or needed to adjust a engine.
In germany Mazda knew that problem and they had traveling techs for there rotarys.
In germany RX7 where sold to people who love the rotary and in germany you use a sportcar a bit different.
I think some 300 units where sold in the 3 years mazda offered the RX7 3gen here.
I heard that the first cars had many qualityproblems in the interiour and some electric problems ( german cars must have a dead look theft protection and those units made trouble ). Some engines had failures mostly covered under waranty but as I heard it most had been just overreved or overchiped.
It is an extreme design that makes lots of power out of such a small compartment, and double the heat of a regular piston engine.
Its just a other engine design with own strenghts and foults.
The rotary is between the piston engine and the turbines. ( remember turbines used in cars ? check the US car history ).
Did you know that the first rotary prototype in 1957 made 30 HP @ 18000 min from just 250 cc. Thats some 120 HP/Liter.
Imagen in 1957 a typical piston engine produced some 25 HP/L and high performance engines where at 50 HP/L.
But the first rotarys didn´t run very long as the spark plug technology only alowed several hours dutytime. And on the first rotarys the sparkplug was siting inside the inner tromboide that was the stator and the outer ring was runing around it.
On the heat problem; that isn´t a real problem for a good engeneer.
But the rotarys need a hot exhaustside and a tuned system ( like two strokes ) to run efficient ( achive high MPG rates ).
It can be modified and I have seen and know people who make 700 to 800 hp out of a turbocharged rotary engine. They only last about 24 hours, but that's the point. they can make extreme power, but they don't last.
What is your point ? some peole built engines with much more power to last for 6 secounds full load.
I´m not sure if a actuall formula 1 engine will last 24 hours
Hell if you need a engine to work 24 hours with total power no one will care if it falls apart in the 25th hour, even worser if it don´t fall apart in the 25th hour you did something wrong and know you could squish out more power are save some wight.
A typicall Formula 2/3000 Ford V8 Cosworth ( 3,0 600 HP ) runs 20-30 Hours and then the powerloos or the risk to break something forces to a partial rebuild. The typical rebuild costs are some 10 000 $. If you overrev or make a other stupid mistake you easily blow 30 000 $ away.
One from my friends worked as a engine mechanic at the Top fueler class. They made a fast "recheck" between the runs. Normaly they only reneweed the head gasket and checked the pistons but sometimes they swaped the complete piston with rod between the runs and replaced the heads. In the 80´s those parts could buy a new Alto or Yugo.
But hell those V8´s pumped over 3000 HP on the wheels.
The question is what are your goals and what will/can you afford to achive that.
all I'm saying is, If you want more power out of your car, make sure it's not a turbocharged rx-7.
Yeah just buy a 400 HP Corvette or a Viper and blow that Mazda away. And if you can´t do it then you can turbocharge that old iron for a handfull dollars and they will never break and drive 100 000 miles without even touching the engine
If you drive a 951 and your car is in good shape then just go down on any racetrack and compare how good the car is in a typical street car field.
You will be surprised that driving fast isn´t relatet to engine power and you will be surprised that "underpowered" cars outperform most Supercars.
The thing is if you have 100000 $ to spent for a car what car what will you do, shop a 996 TT witch is factory stock out from the box reliable full waranty leader from the pack or invest the same money into a RX7 and ask Rod Millen for some good parts. I´m sure the same money in a RX7 will push the performance far beyound the 996 tT. But the next things are.
Are you capable using that power ?
Is the reliability similar and the car able to do daily stop&go and the little missuses we all do for our lazyness ?
How will people react if you spend "that" money into a RX7 and not buying a 996 TT ?
And if you decide to sale that car how much from your investment can be recouped on the marked ?
Grüsse
09-02-2002, 02:18 AM
#22
Burning Brakes
[quote]Originally posted by Roland Kunz:
<strong>I heard that the first cars had many qualityproblems in the interiour and some electric problems Grüsse</strong><hr></blockquote>
I test drove one when they were new. Interior trim pieces kept falling off during the test drive, and that's about when I figured it wasn't the car for me.
<strong>I heard that the first cars had many qualityproblems in the interiour and some electric problems Grüsse</strong><hr></blockquote>
I test drove one when they were new. Interior trim pieces kept falling off during the test drive, and that's about when I figured it wasn't the car for me.
09-02-2002, 08:20 PM
#24
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did you know that the Supra TT and RX7TT both came into the world because ofthe 959. Both companies bought 2 959s to back engineer. One to take apart and one to drive. Also, Nissan did the same thing. That is how the 300ZX TT came to life. So, the 959 is a giggalo behind the ricers
09-06-2002, 02:38 AM
#25
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[quote]Originally posted by Stuttgart951:
<strong>Hehe.. what do you think? Personally? 996TT... come on... no contest here... tossup between RX7 and Supra... I say RX7 beat the Supra out.</strong><hr></blockquote>
ARE YOU KIDDING!!!!!!! RX7 TAKE OUT A SUPRA BAH!!! I think not man.
<strong>Hehe.. what do you think? Personally? 996TT... come on... no contest here... tossup between RX7 and Supra... I say RX7 beat the Supra out.</strong><hr></blockquote>
ARE YOU KIDDING!!!!!!! RX7 TAKE OUT A SUPRA BAH!!! I think not man.
04-25-2005, 01:43 PM
#26
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I have owned 2 93's and I now own a 94 RX-7.I never had any engine problems at all.As a matter of fact,I don't have to worry about changing and breaking timing belts like I do with my 87 944 Turbo.
04-27-2005, 08:48 PM
#27
The big thing about any of these cars is to find one that hasn't been abused. the Mazda has such a boy racer image and is not tough in the corvette sense. So the trick would be to find one in the right condition. Porsches aren't always the fastest car around the track, but are often cited as being the most satisfying ride, best built, etc. The Mazda is also known for weak transmissions, but I think in most cases it is caused by a loose nut in front of the steering wheel. Caveat emptor.
05-08-2005, 11:52 PM
#28
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A few weekends ago at Fontana I saw a very modified, very fast RX7tt running some very very fast laps. The guy had a full crew who knew the car inside and out and could remove, rebuild and reinstall the engine in just over an hour or so. Apparently it's commonly known this car is superfast but at the power level he's running the engine is practically disposable.
There was a Supra TT competing in the same class, he diced with but lost to the RX7 on Saturday, beat it on Sunday because.....yes, you guessed it, the RX7TT engine was starting to let go. The Supra TT was driven to and from the track and was running around 500hp according to the driver. More boost would mean more power but he had a leak somewhere and didn't feel like walking home.
To answer your original question if all the cars meantioned were stock, the Porsche 996TT or 993TT would win hands down. Once you get into purpose built track cars things get a lot more even and a lot more dependent on class specification and driver skill.
There was a Supra TT competing in the same class, he diced with but lost to the RX7 on Saturday, beat it on Sunday because.....yes, you guessed it, the RX7TT engine was starting to let go. The Supra TT was driven to and from the track and was running around 500hp according to the driver. More boost would mean more power but he had a leak somewhere and didn't feel like walking home.
To answer your original question if all the cars meantioned were stock, the Porsche 996TT or 993TT would win hands down. Once you get into purpose built track cars things get a lot more even and a lot more dependent on class specification and driver skill.
