928 crash at Zolder
12-20-2007, 01:03 PM
#31
Rennlist Member
Dont know, but It would be fun to find out! 
Straight line is not a measure of handling
find a top pro in a GT3 and see how their times compare to you at the ring.
You cant claim the best handling 928 around if you are not running on at least semi slicks. on street tires, a miata on semi slicks will give you a race!
are you running Mobil 1?? where are you seeing the dips in oil pressure?
as you know, i have 91 race days on the Holbert machine. nothing holding back and plenty of laps with a 180 degree 80mph sweeping turn at 5000rpms . I never see oil pressure drops. (however we did see some in scots racer with mobil 1 and vavoline synthetic in the turns, which was fixed with amzoil and redline oils)
mk
Straight line is not a measure of handling
find a top pro in a GT3 and see how their times compare to you at the ring.You cant claim the best handling 928 around if you are not running on at least semi slicks. on street tires, a miata on semi slicks will give you a race!
are you running Mobil 1?? where are you seeing the dips in oil pressure?
as you know, i have 91 race days on the Holbert machine. nothing holding back and plenty of laps with a 180 degree 80mph sweeping turn at 5000rpms . I never see oil pressure drops. (however we did see some in scots racer with mobil 1 and vavoline synthetic in the turns, which was fixed with amzoil and redline oils)
mk
I am not sure whether you can get me there - I have never been able to run the car on semi slicks or slicks at the Ring. Biggest problem is oil starvation - I have observed alarming dips on several corners and I value my engine quite highly... I know that I can just about keep up with a GT3 in a straight line...
- I have never been able to run the car on semi slicks or slicks at the Ring. Biggest problem is oil starvation - I have observed alarming dips on several corners and I value my engine quite highly... I know that I can just about keep up with a GT3 in a straight line...
12-20-2007, 07:14 PM
#32
Drifting
mark, not every 2/6 failure is due to mobil one! i will bet you the holbert engine has something a bit special inside to address the known issues with these engines as far as oiling is concerned. give me your engine and i will put slicks on my car btw, what are you doing to address the oiling issues in your next engine??
i do agree with you about jerrys setup on his race car - the rear end appears too stiff or else has an open diff. as far as i know he is running a setup from carl, but he may have increased his spring rates.
i was amazed at the nurburgring 24hrs at thow quickly the cars were going in torrential rain, i guess they must have swapped spring rates as well as ajusted dampers and swapped tyres.
btw, what are you doing to address the oiling issues in your next engine??i do agree with you about jerrys setup on his race car - the rear end appears too stiff or else has an open diff. as far as i know he is running a setup from carl, but he may have increased his spring rates.
i was amazed at the nurburgring 24hrs at thow quickly the cars were going in torrential rain, i guess they must have swapped spring rates as well as ajusted dampers and swapped tyres.
12-20-2007, 07:38 PM
#33
Rennlist Member
mark, not every 2/6 failure is due to mobil one! i will bet you the holbert engine has something a bit special inside to address the known issues with these engines as far as oiling is concerned. give me your engine and i will put slicks on my car btw, what are you doing to address the oiling issues in your next engine??
i do agree with you about jerrys setup on his race car - the rear end appears too stiff or else has an open diff. as far as i know he is running a setup from carl, but he may have increased his spring rates.
i was amazed at the nurburgring 24hrs at thow quickly the cars were going in torrential rain, i guess they must have swapped spring rates as well as ajusted dampers and swapped tyres.
btw, what are you doing to address the oiling issues in your next engine??i do agree with you about jerrys setup on his race car - the rear end appears too stiff or else has an open diff. as far as i know he is running a setup from carl, but he may have increased his spring rates.
i was amazed at the nurburgring 24hrs at thow quickly the cars were going in torrential rain, i guess they must have swapped spring rates as well as ajusted dampers and swapped tyres.
As with regards to the Ring - the guys were running rain tires and BIG ***** too...
12-21-2007, 01:30 AM
#34
Rennlist Member
Cheberator never answered the questions. Mobil 1 in the GT at the ring??
Bet it is.
Now, the holbert engine is not the only engine ive raced. 170,000miles stock 4.7. the 5 liter part euro. And, 3 of scots motors. 4.5, 4.7 and now a full season with the 5 liter. amsoil alows for no drop in oil pressure under high rpms, high temps and high G loading. my only proof is what ive seen when i did use mobile 1.
as far as open diff, that wouldnt cause his spin, but it would cause him to burn rubber on the tighter turns as we heard. the spin was caused by the things i mentioned. probably a combination of the small tires and too stiff rear end, as well as not sliding the car around the turn at a faster speed, so you dont have to hit the gas as hard on the exit. mustangs are real good at that in the old CMC camaro mustang challenge races.
mk
Bet it is.
Now, the holbert engine is not the only engine ive raced. 170,000miles stock 4.7. the 5 liter part euro. And, 3 of scots motors. 4.5, 4.7 and now a full season with the 5 liter. amsoil alows for no drop in oil pressure under high rpms, high temps and high G loading. my only proof is what ive seen when i did use mobile 1.
as far as open diff, that wouldnt cause his spin, but it would cause him to burn rubber on the tighter turns as we heard. the spin was caused by the things i mentioned. probably a combination of the small tires and too stiff rear end, as well as not sliding the car around the turn at a faster speed, so you dont have to hit the gas as hard on the exit. mustangs are real good at that in the old CMC camaro mustang challenge races.
mk
mark, not every 2/6 failure is due to mobil one! i will bet you the holbert engine has something a bit special inside to address the known issues with these engines as far as oiling is concerned. give me your engine and i will put slicks on my car btw, what are you doing to address the oiling issues in your next engine??
i do agree with you about jerrys setup on his race car - the rear end appears too stiff or else has an open diff. as far as i know he is running a setup from carl, but he may have increased his spring rates.
i was amazed at the nurburgring 24hrs at thow quickly the cars were going in torrential rain, i guess they must have swapped spring rates as well as ajusted dampers and swapped tyres.
btw, what are you doing to address the oiling issues in your next engine??i do agree with you about jerrys setup on his race car - the rear end appears too stiff or else has an open diff. as far as i know he is running a setup from carl, but he may have increased his spring rates.
i was amazed at the nurburgring 24hrs at thow quickly the cars were going in torrential rain, i guess they must have swapped spring rates as well as ajusted dampers and swapped tyres.
12-21-2007, 04:31 AM
#35
Rennlist Member
Mobil Delvac 5w40 - drops in oil pressure
Mobil 1 Motorsport 15w50 - drops in oil pressure
Motul Le Mans 15w50 - drops in oil pressure
Castrol RS 10w60 - drops in oil pressure
The last three are racing oils formulated for endurance racing - most of the racers in the VLN use either Motul or Castrol - the engine is fresh from a total rebuilt - all bearings, rings and gaskets, yet I am seeing pressure drops.
Nothing to do with Amsoil or Mobil 1, but everything to do with windage and oil sloshing about the pan. Is it a little wonder that my Z4M engine has a duo-centric oil pump which scavenges from both the the front and rear of the sump?
Alex
12-21-2007, 05:16 AM
#36
12-21-2007, 09:36 AM
#37
Three Wheelin'
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Here ya go!
http://kalecoauto.com/index.php?main...&products_id=4
Also, be sure and read the customer reviews.
Last edited by JEC_31; 12-21-2007 at 09:37 AM. Reason: ...
12-21-2007, 01:01 PM
#39
Rennlist Member
Im not disappointed , im just wondering why i saw such a difference between redline or amsoil and mobil 1 . sure it was a long time ago, but we also saw a drop with vavoline racing syn. There was dramatic pressure level differences at idle and around turns when hot. (racing operating temps, in the 250+F range)
maybe you should try and redline or amsoil and see if its different. sure couldnt hurt, based on my experience or "luck".
I also wonder why ive not seen the problems in the 928 engines ive raced or been responsible for in their racing. 84 4.7, 5 liter in the '84, scots 82 4.5, scots, 82 4.7, scots 82 5 liter. if you want to see some of the sweepers ive run 100s of times, check out this vid:
http://www.youtube.com/watch?v=kj2wN2BrFjs
on the turn 2 sweeper, thats 1.5+ g loading at 5-5500rpm
mK
maybe you should try and redline or amsoil and see if its different. sure couldnt hurt, based on my experience or "luck".
I also wonder why ive not seen the problems in the 928 engines ive raced or been responsible for in their racing. 84 4.7, 5 liter in the '84, scots 82 4.5, scots, 82 4.7, scots 82 5 liter. if you want to see some of the sweepers ive run 100s of times, check out this vid:
http://www.youtube.com/watch?v=kj2wN2BrFjs
on the turn 2 sweeper, thats 1.5+ g loading at 5-5500rpm
mK
Sorry to disappoint you, but I have tried the following oils on track:
Mobil Delvac 5w40 - drops in oil pressure
Mobil 1 Motorsport 15w50 - drops in oil pressure
Motul Le Mans 15w50 - drops in oil pressure
Castrol RS 10w60 - drops in oil pressure
The last three are racing oils formulated for endurance racing - most of the racers in the VLN use either Motul or Castrol - the engine is fresh from a total rebuilt - all bearings, rings and gaskets, yet I am seeing pressure drops.
Nothing to do with Amsoil or Mobil 1, but everything to do with windage and oil sloshing about the pan. Is it a little wonder that my Z4M engine has a duo-centric oil pump which scavenges from both the the front and rear of the sump?
Alex
Mobil Delvac 5w40 - drops in oil pressure
Mobil 1 Motorsport 15w50 - drops in oil pressure
Motul Le Mans 15w50 - drops in oil pressure
Castrol RS 10w60 - drops in oil pressure
The last three are racing oils formulated for endurance racing - most of the racers in the VLN use either Motul or Castrol - the engine is fresh from a total rebuilt - all bearings, rings and gaskets, yet I am seeing pressure drops.
Nothing to do with Amsoil or Mobil 1, but everything to do with windage and oil sloshing about the pan. Is it a little wonder that my Z4M engine has a duo-centric oil pump which scavenges from both the the front and rear of the sump?
Alex
12-21-2007, 01:42 PM
#40
Drifting
mark, maybe you have dodged a bullet on this one. there are a few cars and engines that are or have been tracked without modification to there oiling pathways and have been ok - for a while at least. and then there is everyone else who has toasted rod bearing 2/6. race cars have drysumps regardless of whether they have amsoil. to think a certain oil will save a 928 engine from 2/6 failure is like thinking i can add some stuff into my petrol tank and make the car run more than 200mph!
12-21-2007, 04:49 PM
#41
Rennlist Member
Hey, I'll be the first to agree, there is some luck there!
But, i do have a pretty good track record. 91 race days! thats the most or equal to any 928 chassis in exsistance with its original engine. (or on a single engine without a rebuild like anderson's) with No oil cooler, baffle, drilled crank (that we know about) or accusump, dry sump or anything else. I have, and never have had in any of the 4 engines ive either raced or been responsible for, any blow by issues or other oil related issues.
Either im the luckiest guy in the racing world, besides the 928 world, or we need to take this 928 Holbert motor apart and build all of our 928 motors like it.
On the other hand, what if it is the oil?? It is a possiblity you know. maybe it has just the right film strength, shear protection, viscosity stabilization, or anti foaming that cures the problems that causes oil starvation in our cars. Considering the type of racing that engine of mine has been though, something has to be going on except a something just short of a modern miracle!
mk
But, i do have a pretty good track record. 91 race days! thats the most or equal to any 928 chassis in exsistance with its original engine. (or on a single engine without a rebuild like anderson's) with No oil cooler, baffle, drilled crank (that we know about) or accusump, dry sump or anything else. I have, and never have had in any of the 4 engines ive either raced or been responsible for, any blow by issues or other oil related issues.
Either im the luckiest guy in the racing world, besides the 928 world, or we need to take this 928 Holbert motor apart and build all of our 928 motors like it.
On the other hand, what if it is the oil?? It is a possiblity you know. maybe it has just the right film strength, shear protection, viscosity stabilization, or anti foaming that cures the problems that causes oil starvation in our cars. Considering the type of racing that engine of mine has been though, something has to be going on except a something just short of a modern miracle!
mk
mark, maybe you have dodged a bullet on this one. there are a few cars and engines that are or have been tracked without modification to there oiling pathways and have been ok - for a while at least. and then there is everyone else who has toasted rod bearing 2/6. race cars have drysumps regardless of whether they have amsoil. to think a certain oil will save a 928 engine from 2/6 failure is like thinking i can add some stuff into my petrol tank and make the car run more than 200mph!
12-21-2007, 06:59 PM
#43
Addict
Rennlist Member
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Kibort has a good idea...take the Holbert engine apart and, once and for all, discover what was done to this engine to make it "special." I'll bet there'd be few that wouldn't want the same mods. Based on the orginal intent of the Holbert car, who it was built for, and what they were shooting for.....it stands to reason that some great racing mechanic may have done something special to this particular engine. Balanced and blueprinted with other subtle mods (or not so subtle)? I guess we won't know until Mark' engine fails and he takes it apart. Or, we'd better all rush out and buy Amsoil!
H2
H2
12-21-2007, 07:22 PM
#44
Burning Brakes
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It's not just luck.
I've watched your onboard clips. You pedal good without thrashing the engine, box or diff. Perhaps you have a 6th sense in your driving - Mechanical sense.
Cheers,
Pierre.
I've watched your onboard clips. You pedal good without thrashing the engine, box or diff. Perhaps you have a 6th sense in your driving - Mechanical sense.
Cheers,
Pierre.
Hey, I'll be the first to agree, there is some luck there!
But, i do have a pretty good track record. 91 race days! thats the most or equal to any 928 chassis in exsistance with its original engine. (or on a single engine without a rebuild like anderson's) with No oil cooler, baffle, drilled crank (that we know about) or accusump, dry sump or anything else. I have, and never have had in any of the 4 engines ive either raced or been responsible for, any blow by issues or other oil related issues.
Either im the luckiest guy in the racing world, besides the 928 world, or we need to take this 928 Holbert motor apart and build all of our 928 motors like it.
On the other hand, what if it is the oil?? It is a possiblity you know. maybe it has just the right film strength, shear protection, viscosity stabilization, or anti foaming that cures the problems that causes oil starvation in our cars. Considering the type of racing that engine of mine has been though, something has to be going on except a something just short of a modern miracle!
mk
But, i do have a pretty good track record. 91 race days! thats the most or equal to any 928 chassis in exsistance with its original engine. (or on a single engine without a rebuild like anderson's) with No oil cooler, baffle, drilled crank (that we know about) or accusump, dry sump or anything else. I have, and never have had in any of the 4 engines ive either raced or been responsible for, any blow by issues or other oil related issues.
Either im the luckiest guy in the racing world, besides the 928 world, or we need to take this 928 Holbert motor apart and build all of our 928 motors like it.
On the other hand, what if it is the oil?? It is a possiblity you know. maybe it has just the right film strength, shear protection, viscosity stabilization, or anti foaming that cures the problems that causes oil starvation in our cars. Considering the type of racing that engine of mine has been though, something has to be going on except a something just short of a modern miracle!
mk
12-21-2007, 07:43 PM
#45
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I'll defer to your opinion/ experience
