Engine ka-boom follow-up
#16
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Originally Posted by Steve Weiner-Rennsport Systems
these later long-stroke cranks have more trouble getting sufficient oil to the center two rod journals. In addition, the stock 3.6 oil pumps do not quite deliver sufficient oil pressure & volume at high RPM.
Sorry to hear of your travails, Tom. Hope the wallet hit isn't too bad.
#17
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ugly...
very sorry to see that hole in the case, tom.
i guess this pretty much ends the season for you as i assume it will take 2 months or so to wrap it up and then we'll hit rain season again. i hope to see you and the turtle as soon as you have it patched up.
good luck.
very sorry to see that hole in the case, tom.
i guess this pretty much ends the season for you as i assume it will take 2 months or so to wrap it up and then we'll hit rain season again. i hope to see you and the turtle as soon as you have it patched up.
good luck.
#19
King of Cool
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Sorry to hear Tom.
As soon as I saw you post I though TT motor (to "spice up" things a bit) but since you're staying stock, that's out of the picture.
Good luck with the re-build.
As soon as I saw you post I though TT motor (to "spice up" things a bit) but since you're staying stock, that's out of the picture.
Good luck with the re-build.
#20
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Originally Posted by Steve Weiner-Rennsport Systems
Tom: Its not a question of adequate oil supply, its an issue with all 911 engines at certain RPM levels. Its not about HP, its about long-term durability for track events.
#21
Three Wheelin'
Steve I would also like to know what the story is on the 3.6 and oiling issues at higer RPMs....I tend to operate my car at higher RPMs once the motor is warmed up and don't need my only car's engine to go ka-boom on me
#22
RL Technical Advisor
Originally Posted by Chuck W.
Steve...If you do not track your 993 is this still an issue.
Not to worry, sir. This is no issue for street use.
Cole:
This is a somewhat complex subject and many things can be taken out of context. If one operates these engines within their design parameters without overrevving the motor, they are VERY durable.
Some people can run into trouble when missing a shift (where the rev limiter is useless) or using the engine as a brake to slow the car down. That puts very high loads into the rods and rod bolts.
For cars that see a great deal of track use (whether its DE or competition), we like to perform some upgrades strictly for the sake of durability under those kinds of circumstances.
Please feel free to call me for more information, if you need it.
#23
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Originally Posted by Steve Weiner-Rennsport Systems
Some people can run into trouble when missing a shift (where the rev limiter is useless) or using the engine as a brake to slow the car down. That puts very high loads into the rods and rod bolts.
Would you not recommend downshifting (for purpose of engine braking) during normal daily driving?
#25
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Originally Posted by infinii
Would you not recommend downshifting (for purpose of engine braking) during normal daily driving?
#26
RL Technical Advisor
Originally Posted by infinii
Would you not recommend downshifting (for purpose of engine braking) during normal daily driving?
LOL,..I recommend using the engine to accelerate the car out of a corner and beyond. I think one uses the brakes to slow the car to the corner entry speeds that you are comfortable with.
Brake pads/rotors, etc are really far cheaper than engine parts,....
#27
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I took the car to Jerry Woods last night. They also said that the #5 rod bearing failure is usually due to insufficient oiling. The bearing burns and seizes then the rod breaks and all hell breaks loose (as in ka-boom). They will begin tearing the engine down in the next day or two to see if they can determine the exact cause and determine what course to pursue for the rebuild/replacement. (I had full oil and good pressure when it died.)
#28
Rennlist Member
Originally Posted by infinii
Would you not recommend downshifting (for purpose of engine braking) during normal daily driving?
If you're going to downshift, you should learn how to heel-and-toe so that you can be as gentle as possible with the car.
#29
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Funny.....Derek Bell told me the same thing...
Originally Posted by Steve Weiner-Rennsport Systems
LOL,..I recommend using the engine to accelerate the car out of a corner and beyond. I think one uses the brakes to slow the car to the corner entry speeds that you are comfortable with.
Brake pads/rotors, etc are really far cheaper than engine parts,....
Brake pads/rotors, etc are really far cheaper than engine parts,....
Cheers,
#30
RL Technical Advisor
Originally Posted by Fred R. C4S
Derek skip shifted from 5th directly to either 2nd or 3rd under HEAVY braking. When I asked why he didn't go down the box gear by gear, he pointed out the brake pads were by FAR the cheapest, most reliable, and fool proof way to slow a car. Particularly a street car with a nonprofessional driver.
Great advice from one of THE all-time pro's.
Although thats what I've done for many years, I'd just caution anyone that going from 5th to 2nd (or 3rd) does increase the risk of selecting the wrong gear, particularly when one is not paying close attention or suffering from a slight bout of the "Red Mist",......... One must ensure that the shifter and all its components are in perfect shape to prevent an expensive overrev.
Thats what really places huge tensile loads on the connecting rods and bolts.