Dynapack Dyno Results - Looking Good!!
09-20-2010, 02:41 AM
#1
Rennlist Member
Thread Starter
Dynapack Dyno Results - Looking Good!!
Hi All,
Today was a fun day. The 993 finally got benchmarked. Bob Homewood the owner of Hitech MotorSport in Drury (about 60km South of Auckland CBD) has been using the Dynapack Hub mounted chassis Dyno for 15 years. The Dynapack 4000 is arguably one of the most accurate tools of its breed as it is hub mounted and reduces inaccuracies due to frictional losses of a wheel and roller system. Bob and his family run a niche race shop, never advertise and do top class work including their own fabrication. Dynapack is a New Zealand invention and is exported globally and very well revered by race shops around the planet. Bob is one of the most trusted and experienced operators of this gear in NZ having used the system since its inception. His Dyno room is like a hospital ward and his race shop so clean you could eat your proverbial off of it.....
After setting up (a good 35 minutes due to the hub mounted nature of the system) we were ready to go. Bob used only a 9% drive train loss factor on this car. This was definately on the agressive side, however he explained the V8 race cars they work on have shown as low as 9% from engine to chassis dyno and given my 993 has LWFC. is manual with solid engine and tranny mounts this was ikely the worse case senario. In reality a 10-11% factor was probably more relaistuic making these figures even better still...
Ok. How did we go? For those of you wanting to now the latest spec of my 993 you will find a post called "Self Gratification with Pictures" whic I will be updating in the next few days with the additional 10 or so modifications recently made to teh car including a new MAF and Dac X catless pipes etc
Factory Tech Manual said:
272 bhp @ 6100 rpm = Peak Power
243.36 lbft @ 5000 rpm = Peak Torque
Dynapack 4000 @ 16 celcius day, 4th gear 9% loss factor:
287.36 bhp @ 6252 rpm = Peak Power (+ 5.6%) – 184.7kmph
255.11 lbft @ 5429 rpm = Peak Torque (+ 4.8%) – 160.8 kmph
Dynapack 4000 @ 16 celcius day, 4th gear 10% loss factor:
290.00 bhp @ 6252 rpm = Peak Power – 184.7kmph
257.45 lbft @ 5429 rpm = Peak Torque – 160.8 kmph
Fuel was fresh 98 octane RON mixed 50:50 with six month old 98 octane so running possibly as low as 96-97 RON.
We also ran a full set of Lambda (Fuelling) graphs and charts to plot how the engine handled during the run. It looks like the engine sits 0.88 mostly with a few lumps along the way which could be nicely trimmed if I were running a system such as Link or Motec. However the main thing was no big lean dips so the engine is in the safe zone.
So am I happy with the outcome? Sure am. Remembering that its pretty rare for a 17 year old engine with 70k km on it to make quoted factory power (and Rennlist is awash of charts that demonstrate the factory figure is very hard to achieve), then my 6-7% increase points to a very positive outcome. More importantly the car feels very strong and as if its making that power.
Ive attached some pictures and a graph for those who may b interested. I have other graphs and plots as well as a video which is too large to post. The car sure sounded outrageous being wound out to 6700 rpm.
Today was a fun day. The 993 finally got benchmarked. Bob Homewood the owner of Hitech MotorSport in Drury (about 60km South of Auckland CBD) has been using the Dynapack Hub mounted chassis Dyno for 15 years. The Dynapack 4000 is arguably one of the most accurate tools of its breed as it is hub mounted and reduces inaccuracies due to frictional losses of a wheel and roller system. Bob and his family run a niche race shop, never advertise and do top class work including their own fabrication. Dynapack is a New Zealand invention and is exported globally and very well revered by race shops around the planet. Bob is one of the most trusted and experienced operators of this gear in NZ having used the system since its inception. His Dyno room is like a hospital ward and his race shop so clean you could eat your proverbial off of it.....
After setting up (a good 35 minutes due to the hub mounted nature of the system) we were ready to go. Bob used only a 9% drive train loss factor on this car. This was definately on the agressive side, however he explained the V8 race cars they work on have shown as low as 9% from engine to chassis dyno and given my 993 has LWFC. is manual with solid engine and tranny mounts this was ikely the worse case senario. In reality a 10-11% factor was probably more relaistuic making these figures even better still...
Ok. How did we go? For those of you wanting to now the latest spec of my 993 you will find a post called "Self Gratification with Pictures" whic I will be updating in the next few days with the additional 10 or so modifications recently made to teh car including a new MAF and Dac X catless pipes etc
Factory Tech Manual said:
272 bhp @ 6100 rpm = Peak Power
243.36 lbft @ 5000 rpm = Peak Torque
Dynapack 4000 @ 16 celcius day, 4th gear 9% loss factor:
287.36 bhp @ 6252 rpm = Peak Power (+ 5.6%) – 184.7kmph
255.11 lbft @ 5429 rpm = Peak Torque (+ 4.8%) – 160.8 kmph
Dynapack 4000 @ 16 celcius day, 4th gear 10% loss factor:
290.00 bhp @ 6252 rpm = Peak Power – 184.7kmph
257.45 lbft @ 5429 rpm = Peak Torque – 160.8 kmph
Fuel was fresh 98 octane RON mixed 50:50 with six month old 98 octane so running possibly as low as 96-97 RON.
We also ran a full set of Lambda (Fuelling) graphs and charts to plot how the engine handled during the run. It looks like the engine sits 0.88 mostly with a few lumps along the way which could be nicely trimmed if I were running a system such as Link or Motec. However the main thing was no big lean dips so the engine is in the safe zone.
So am I happy with the outcome? Sure am. Remembering that its pretty rare for a 17 year old engine with 70k km on it to make quoted factory power (and Rennlist is awash of charts that demonstrate the factory figure is very hard to achieve), then my 6-7% increase points to a very positive outcome. More importantly the car feels very strong and as if its making that power.
Ive attached some pictures and a graph for those who may b interested. I have other graphs and plots as well as a video which is too large to post. The car sure sounded outrageous being wound out to 6700 rpm.
Last edited by Macca; 09-21-2010 at 12:21 AM.
09-20-2010, 12:48 PM
#3
Nordschleife Master
Impressive!!! Congrats!
Part of the reason for the low drive train loss is the fact you are NOT using your tires on the Dynapac. You get slightly higher numbers due to the fact the car doesn't need to rotate the rim/tire, & there is 0% chance of the tire slipping on the rollers, since the hub is mounted to the machine. It removes some variables. I have seen a AWD car light it it's tires on the dyno around 100mph, it was crazy!
Did you ask if they have done other 993's there? It's always nice to see what they did on the same dyno,.
Part of the reason for the low drive train loss is the fact you are NOT using your tires on the Dynapac. You get slightly higher numbers due to the fact the car doesn't need to rotate the rim/tire, & there is 0% chance of the tire slipping on the rollers, since the hub is mounted to the machine. It removes some variables. I have seen a AWD car light it it's tires on the dyno around 100mph, it was crazy!
Did you ask if they have done other 993's there? It's always nice to see what they did on the same dyno,.
09-20-2010, 03:24 PM
#5
Rennlist Member
Thread Starter
Hi Bill.
Yes it is stock G50/21 ROW early 993 trans. 4th gear ratio is specificed at factory at 4.2795
Bob chose 4.2760 as the closest 4th gearset ratio programed into Dynapack. I asked him is the 0.0035 would make any descernable difference and he said no it wouldnt. I guess ultimately we are considering relativity here as well (i.e. a base line for future mods tested back again on teh same Dyno)...
Cheers
M
Yes it is stock G50/21 ROW early 993 trans. 4th gear ratio is specificed at factory at 4.2795
Bob chose 4.2760 as the closest 4th gearset ratio programed into Dynapack. I asked him is the 0.0035 would make any descernable difference and he said no it wouldnt. I guess ultimately we are considering relativity here as well (i.e. a base line for future mods tested back again on teh same Dyno)...
Cheers
M
09-20-2010, 03:54 PM
#6
Hi Bill.
Yes it is stock G50/21 ROW early 993 trans. 4th gear ratio is specificed at factory at 4.2795
Bob chose 4.2760 as the closest 4th gearset ratio programed into Dynapack. I asked him is the 0.0035 would make any descernable difference and he said no it wouldnt. I guess ultimately we are considering relativity here as well (i.e. a base line for future mods tested back again on teh same Dyno)...
Cheers
M
Yes it is stock G50/21 ROW early 993 trans. 4th gear ratio is specificed at factory at 4.2795
Bob chose 4.2760 as the closest 4th gearset ratio programed into Dynapack. I asked him is the 0.0035 would make any descernable difference and he said no it wouldnt. I guess ultimately we are considering relativity here as well (i.e. a base line for future mods tested back again on teh same Dyno)...
Cheers
M
3.44 x 1.242 gives 4.277 so the 4.276 is certainly close enough, nice results!
09-20-2010, 04:39 PM
#7
Rennlist Member
Thread Starter
Thanks Bill. Your feedback and comments are always appreciated.
Stealth 993. I did indeed ask Bob. He is one of the busier Dynos in NZ doing around 3000 runs a year. We are only a small country but we do try and punch above our weight. Bob has been with Dynapack since they started. Given its NZ manufacured he has invaribaly had alot of input in the product in the 15 years hes been using it. He has indeed tested 993 ad 964 befoe but Bob is one of these old school guys. he doesnt pass opinion and only fact. Very quiet guy. When he speaks you know its important. He was also very professional. Essentially he would not share any other clients data with me. Hes not an excitable guy and so didnt make any rash observations about the relative performance of my 993. He did however indicate that in stock trim it was unusual for any engine tested over a decade old and which hadnt seen any internal work to make factory quoted horsepower, with the exception being sme of the Japanese stuff I guess (think GTRs etc that were likely miss quoted from factory). He was very passinate on the fcat that NZ fuel blends were not as good as they once were and that alot of the fuel sold in NZ now came from cheaper sources/refineries and was in his words "often crap". He stated this alone could have significant effects on the performance of a fairly highly tuned engine on his dyno. Unfortunately my fuel was a mix of old and new so likely also slightly low on Octane and possibly quality...
Cheers
M
Stealth 993. I did indeed ask Bob. He is one of the busier Dynos in NZ doing around 3000 runs a year. We are only a small country but we do try and punch above our weight. Bob has been with Dynapack since they started. Given its NZ manufacured he has invaribaly had alot of input in the product in the 15 years hes been using it. He has indeed tested 993 ad 964 befoe but Bob is one of these old school guys. he doesnt pass opinion and only fact. Very quiet guy. When he speaks you know its important. He was also very professional. Essentially he would not share any other clients data with me. Hes not an excitable guy and so didnt make any rash observations about the relative performance of my 993. He did however indicate that in stock trim it was unusual for any engine tested over a decade old and which hadnt seen any internal work to make factory quoted horsepower, with the exception being sme of the Japanese stuff I guess (think GTRs etc that were likely miss quoted from factory). He was very passinate on the fcat that NZ fuel blends were not as good as they once were and that alot of the fuel sold in NZ now came from cheaper sources/refineries and was in his words "often crap". He stated this alone could have significant effects on the performance of a fairly highly tuned engine on his dyno. Unfortunately my fuel was a mix of old and new so likely also slightly low on Octane and possibly quality...
Cheers
M
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09-22-2010, 06:04 AM
#8
Rennlist Member
Thread Starter
A few of you may be interested in AFRs. I will try to post the lambda vs power curves and raw lambda data tommorow on this thread for future reference....
Cheers
M
Cheers
M
09-22-2010, 08:49 PM
#9
Rennlist Member
Thread Starter
Attached is a torque vs fuel mix curve. A few lumpy bits partially due to the way the dynapack works being bolted right to the hubs. Poor fuel doesnt help but it appears the engine seems to conform to the general normal pattern of under fuelling on initial WOT and then over fueling a bit higher on the rev range. At least thats what I recall being the explanation to read the graph on the right but I may be wrong. The Dyno operator Bob said if he were remapping the ECU he would flatten the peaks and troughs around the 0.88-0.885 mark....
