Strap points when placing 930 on the dyno
01-31-2003, 09:36 PM
#2
Racer
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I think our dyno shop attaches the straps to the trailing arms.
One thing to watch for is the wastegate venting on the straps. I almost completely melted the left strap holding my car down. Scary.
One thing to watch for is the wastegate venting on the straps. I almost completely melted the left strap holding my car down. Scary.
01-31-2003, 10:20 PM
#3
Nordschleife Master
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They mount them to the rear factory tie downs located on each frame rail. They usually install two straight back and two criss crossed. The front wheels are chocked and straps are connected to the diagonals where it meets the torsion bars.
When you do dyno it, make sure they/you have fans that can blow on the intercooler and and another one to blow engine heat away from below. I use the fan between runs and a bag of ice or two to cool down the intercooler. The more you do w/o proper cool downs for the motor, the hotter it will get and less power you will make. I've done it with the lid open, but it's better to close it with the fan on the tail.
Start in third gear at 3k rpm and take it as high as you can go. It will be scary as hell with a wall in front of you, but worth it.
On one of my first dynos, my speedo said 170 mph! I felt better at Road Atlanta the week before driving at 150.
Jim
When you do dyno it, make sure they/you have fans that can blow on the intercooler and and another one to blow engine heat away from below. I use the fan between runs and a bag of ice or two to cool down the intercooler. The more you do w/o proper cool downs for the motor, the hotter it will get and less power you will make. I've done it with the lid open, but it's better to close it with the fan on the tail.
Start in third gear at 3k rpm and take it as high as you can go. It will be scary as hell with a wall in front of you, but worth it.
On one of my first dynos, my speedo said 170 mph! I felt better at Road Atlanta the week before driving at 150.
Jim
02-01-2003, 03:46 PM
#4
Rennlist Member
I would second John's warning about the tie down straps. My car was tested while held by two heavy nylon straps attached to the trailing arms. After the second run, I just happened to notice that the left strap, running just under the wastegate muffler, was melted about 80% across! The shop I was at does mostly BMWs so they weren't thinking 930. They replaced the strap with another, and wrapped it with header insulating material. Also, they had me run the car in second gear, full throttle from idle to redline. Cooling the intercooler is critical while running full throttle standing still.
02-02-2003, 01:09 AM
#5
Rennlist Member
A carpet drying fan works great for blowing air across the IC. It is like a giant huge CFM scroll fan. You can rent them at any tool rental place. The Home Depot where I live rents them for about $17 for the day.
Justin
Justin
02-02-2003, 12:26 PM
#6
Cruisin'
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I just had my 930 on a dyno at a club event. First time. They ran a strap thru the car behind the front seats. Seemed to work fine. But now that I read these posts , I question the wisdom of just one strap and where it was placed. Not having a secondary seems kind of stupid. And this was at a Porsche shop. Eastside
02-02-2003, 08:34 PM
#7
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WHOA! That would make me awfully nervous. Certainly they should have known where to attach the straps. Sounds like someone was in a hurry. Find a new shop if you can.
Jim
BTW. Hope your numbers were good.
Jim
BTW. Hope your numbers were good.
