Titanium Rods/ aftermarket pistons
01-20-2003, 11:25 AM
#16
here is a place, have no idea on the quality of design....
<a href="http://www.paeco.com/" target="_blank">http://www.paeco.com/</a>
<a href="http://www.paeco.com/" target="_blank">http://www.paeco.com/</a>
01-20-2003, 12:17 PM
#17
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Hi Fusionsport,
Yes I can certainly agree with your advice, now, that this fellow has to go for the high-end rods - initially I had no idea he was quite literally intending on doubling the stock horsepower and revving the hell out of it. I gave out the 'shotpeen' advice under the assumption that he was doing a rebuild to his engine with no particular horsepower target in mind, but wanting something stronger. Knowing he intends on taking the 3.0 litre engine to 7100 RPMS changes things.
So are you saying that the Carrera GT rods were further modified? How so? Like, I would guess lightened further (or selected from a bin of rods to be of equal weight), balanced and then de-stressed. Is that about right? Or what did they do to these to make them stronger? I want to know just because I want to see how close the work I did on my car matches up to the GT.
By the way, hearing what you've said about these early cars makes me grateful I put in the time, bucks and effort making the bottom end of my car stronger!
Turby: There's something I'm not understanding here about the car: Why can't you achieve the same power goals, with these big 4's, and good engine management, without exceeding the stock redline? Like, how do you know you now must use the rest of the RPM curve, and beyond, to achieve your goal? Or is going beyond redline to 7100 something that you'd want to do after you've exhausted the other avenues for power?
Yes I can certainly agree with your advice, now, that this fellow has to go for the high-end rods - initially I had no idea he was quite literally intending on doubling the stock horsepower and revving the hell out of it. I gave out the 'shotpeen' advice under the assumption that he was doing a rebuild to his engine with no particular horsepower target in mind, but wanting something stronger. Knowing he intends on taking the 3.0 litre engine to 7100 RPMS changes things.
So are you saying that the Carrera GT rods were further modified? How so? Like, I would guess lightened further (or selected from a bin of rods to be of equal weight), balanced and then de-stressed. Is that about right? Or what did they do to these to make them stronger? I want to know just because I want to see how close the work I did on my car matches up to the GT.
By the way, hearing what you've said about these early cars makes me grateful I put in the time, bucks and effort making the bottom end of my car stronger!
Turby: There's something I'm not understanding here about the car: Why can't you achieve the same power goals, with these big 4's, and good engine management, without exceeding the stock redline? Like, how do you know you now must use the rest of the RPM curve, and beyond, to achieve your goal? Or is going beyond redline to 7100 something that you'd want to do after you've exhausted the other avenues for power?
01-20-2003, 02:45 PM
#18
Race Director
"when you talk in terms of I beam vs H beam is this in reference to the pauter vs the carillo?"
No, I'm just talking about the physics behind the geometry and how it deals with the various loads present in an engine. Both Pauter and Carrillo makes rods in both designs. The trick is to balance strength to weight and optimize that for your particular application. The Carrillos tend to be overbuilt, thus their extra weight. The other trick is strong bolts. You want at least 200,000psi tensile-strength on the bolts (better 250K+).
No, I'm just talking about the physics behind the geometry and how it deals with the various loads present in an engine. Both Pauter and Carrillo makes rods in both designs. The trick is to balance strength to weight and optimize that for your particular application. The Carrillos tend to be overbuilt, thus their extra weight. The other trick is strong bolts. You want at least 200,000psi tensile-strength on the bolts (better 250K+).
01-20-2003, 05:57 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by BigPorscheGuy39:
<strong>
Turby: There's something I'm not understanding here about the car: Why can't you achieve the same power goals, with these big 4's, and good engine management, without exceeding the stock redline? Like, how do you know you now must use the rest of the RPM curve, and beyond, to achieve your goal? Or is going beyond redline to 7100 something that you'd want to do after you've exhausted the other avenues for power?</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Not that I WILL, but that I will be ABLE to if needed. The turbo I am using is the main reason for me thinking it would be better to rev to 7100k, a 60-1 garrett ball bearing # 10 hotside. Good engine management is a must, havent decided which route to go there yet.
<strong>
Turby: There's something I'm not understanding here about the car: Why can't you achieve the same power goals, with these big 4's, and good engine management, without exceeding the stock redline? Like, how do you know you now must use the rest of the RPM curve, and beyond, to achieve your goal? Or is going beyond redline to 7100 something that you'd want to do after you've exhausted the other avenues for power?</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Not that I WILL, but that I will be ABLE to if needed. The turbo I am using is the main reason for me thinking it would be better to rev to 7100k, a 60-1 garrett ball bearing # 10 hotside. Good engine management is a must, havent decided which route to go there yet.
01-20-2003, 06:32 PM
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Just recievd a emai from Pauter the rods will cost $2195, weigh 480-500 grams each as opposed to 700 grams for chromeoly, and take up to 14 weeks to deliver. What do you guys think?
01-21-2003, 12:17 AM
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piston choices are about endless
Venolia, JE, Wiseco, Mahle are all good choices. Cosworth are likely the best piston on earth but are a bit pricey. Malvern Motorsports is the Importer for them.
Venolia, JE, Wiseco, Mahle are all good choices. Cosworth are likely the best piston on earth but are a bit pricey. Malvern Motorsports is the Importer for them.
01-21-2003, 12:37 AM
#23
Race Director
There's rumor that Mahle is making another batch of 104mm 968 iron-coated pistons to work in the stock bores. Comes in stock compression as well as lower 8.5:1 or so for turbo applications... hmmm.....
01-21-2003, 02:20 AM
#24
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This is the latest email from Pauter;
Morgan,
I'm not familiar with 6/4 ti, we use 6AL4V titanium. I would really recommend against using titanium pins. They would have to be made with such a heavy wall thickness that you would wind up with a similar weight piece and have the problem of galling in the piston and rod. Bushings must be used with any floating pin setup and epecially with titanium rods. Overall, you would probably save about 400g but I doubt you would get much more weight savings out of it. You might want to consider lightening and knife-edging the crank which will save 11-12 pounds and lightening the flywheel which will save an additional 7-8 pounds.
Brian
Hey Danno, anyway to confirm that from Mahle?
fusionsport, thanks for all the options!
Morgan,
I'm not familiar with 6/4 ti, we use 6AL4V titanium. I would really recommend against using titanium pins. They would have to be made with such a heavy wall thickness that you would wind up with a similar weight piece and have the problem of galling in the piston and rod. Bushings must be used with any floating pin setup and epecially with titanium rods. Overall, you would probably save about 400g but I doubt you would get much more weight savings out of it. You might want to consider lightening and knife-edging the crank which will save 11-12 pounds and lightening the flywheel which will save an additional 7-8 pounds.
Brian
Hey Danno, anyway to confirm that from Mahle?
fusionsport, thanks for all the options!
01-21-2003, 05:43 AM
#25
Race Director
"I'm not familiar with 6/4 ti, we use 6AL4V titanium"
Same stuff. This particular alloy can't be forged because it work-hardens so quickly that it destroys the die... heh, heh
"Hey Danno, anyway to confirm that from Mahle?"
I'll check up on that. Last I heard, they had brought in some blanks...
Same stuff. This particular alloy can't be forged because it work-hardens so quickly that it destroys the die... heh, heh
"Hey Danno, anyway to confirm that from Mahle?"
I'll check up on that. Last I heard, they had brought in some blanks...
01-21-2003, 06:42 AM
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Yeah I figured it was the same stuff, I wonder why he didnt pick up on it?
Ya know, I remember hearing this factory 968T piston thing a while back too.........If I havent said it lately, "Danno, You DA MAN!"
Anyone know why the early factory 968 turbos were breaking rods, and what exactly did they change? Konstantin?........Sorry if I didnt spell it right.
Ya know, I remember hearing this factory 968T piston thing a while back too.........If I havent said it lately, "Danno, You DA MAN!"
Anyone know why the early factory 968 turbos were breaking rods, and what exactly did they change? Konstantin?........Sorry if I didnt spell it right.
01-21-2003, 11:47 PM
#27
Those prices for the Ti rods are pretty crazy danno. 125 a rod for Titanium?
I am asking because, well, you guys have half my engine.
Anything (except for the crank) that you guys fine that works really well, I can simply use twice as many in my two 928s. Well, at least in my 81 928.
I think I don't quite get the email that was reciepved regarding the Ti wrist pins? I do know that Ti is not good for sliding wear - meaning it galls easily....
I am asking because, well, you guys have half my engine.
Anything (except for the crank) that you guys fine that works really well, I can simply use twice as many in my two 928s. Well, at least in my 81 928.
I think I don't quite get the email that was reciepved regarding the Ti wrist pins? I do know that Ti is not good for sliding wear - meaning it galls easily....
01-22-2003, 02:05 AM
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BigPorscheGuy39- I am not sure how Porsche went about selecting the rods for the GTS, but I do know when I was researching OEM parts for my GT-3 car I was specifically told that the oem rods even peened and prepared were not up to over 210 hp reliably- and that a "special" rod must be used over that, given Porsches history I would conclude that to mean a Ti rod, or a forged steel rod. In the "production" cars like the GTS I am assuming the rods were carefully chosen and machined in matched sets. As I recall the engines for the production GTS wasnt particulary plagued with problems from the bottom end, ad none of the 924 series ever was. The 928 CIS fuel distributor throws people off though, and the few cars left here in the states seem to be seldom driven. I have the tub from my GT3 car and have thought several times about doing it as a GTS historic or PCA car, as I think it would just be too cool.
Danno- I know the director of motorsports over at Mahle, and your rumor has started me to thinking i should give him a call....
Turby- Pauter does EXCELLENT machine work and will do a phenomenal job if you chose to have him lighten/knife edge your crank
Danno- I know the director of motorsports over at Mahle, and your rumor has started me to thinking i should give him a call....
Turby- Pauter does EXCELLENT machine work and will do a phenomenal job if you chose to have him lighten/knife edge your crank
01-22-2003, 03:08 AM
#29
Race Car
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Turby:
<strong>Anyone know why the early factory 968 turbos were breaking rods, and what exactly did they change?</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Can I see a source for this data? Thanks.
<strong>Anyone know why the early factory 968 turbos were breaking rods, and what exactly did they change?</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Can I see a source for this data? Thanks.
01-22-2003, 04:39 AM
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Hello
As described in the 968 shop manual Porsche changed the rod on 93 968 because of weakness on the bolt shoulder - I presume the 968 TS had the same rods as the standard 968...
Nicolas
As described in the 968 shop manual Porsche changed the rod on 93 968 because of weakness on the bolt shoulder - I presume the 968 TS had the same rods as the standard 968...
Nicolas