Dyno Day at Altered Atmosphere in MD!
May 25, 2003, 04:06 PM
#77
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I put down 274/256 and after a little afc tuning 271/270. I have a 3" testpipe, Pruven axle back, K&N drop in and SAFC 2.
Last edited by Stinkapuss; May 25, 2003 at 04:23 PM.
May 25, 2003, 07:50 PM
#79
Originally posted by modvp
It was really cool hanging out with you guys on Saturday, you guys are great. It was lots of fun, I got to see a bunch of really great cars too…the EVO’s are awesome looking in person.
The WRX was a somewhat intimidated by the rather big gathering of EVO’s. I parked it far away though...looked a bit out of place.
It was really cool hanging out with you guys on Saturday, you guys are great. It was lots of fun, I got to see a bunch of really great cars too…the EVO’s are awesome looking in person.
The WRX was a somewhat intimidated by the rather big gathering of EVO’s. I parked it far away though...looked a bit out of place.
Regards,
May 25, 2003, 08:21 PM
#80
Originally posted by Stinkapuss
I put down 274/256 and after a little afc tuning 271/270. I have a 3" testpipe, Pruven axle back, K&N drop in and SAFC 2.
I put down 274/256 and after a little afc tuning 271/270. I have a 3" testpipe, Pruven axle back, K&N drop in and SAFC 2.
Stinkapuss -
I was very impressed by your performance numbers with those modifications. Certainly less money to get there than I have spent. The key to performance increases clearly start with A/F mapping which you have done quite well just by using your track times. I would imagine that you can clean up any additional drivability qwirks using the dyno graph's A/F plot.
I gotta wonder if your numbers are typical or if you have one of the healthier cars. Makes me want to remove my 3" exhaust and do another run with just the XEDE to see if I would retain my 272.4 HP and 263.9 TQ.
Last Monday I ran a baseline for complete stock setup at Altered and recorded a 1st run of 240.4 HP and 251.3 TQ. Two successive runs that day were 230 and 235 HP respectively. A/F was very erratic. Still, average between the three was 235 HP. The baseline yesterday after the installation of the 3" turbo-back was only 240.1 HP. I honestly expected a larger gain than 5 HP from the exhaust. Now part of the lower numbers were attributable to the rainy day and high humidity we experienced yesterday compared to Monday's cool clear day. I just don't like not being able to quantify how much the humidity really cost in terms of performance.
Only way to be sure is to go back and: 1) test turbo-back exahust with and without XEDE, 2) remove DP and 3" cat and test cat-back with and without XEDE, 3) remove cat-back and test stock exhaust with and without XEDE. Figuring 3 pulls per configuration, that means 18 runs and the better part of a full day.
Don't know if all that work is really worth the effort, time, and expense involved. However, it would be nice to know for sure what those individual upgrades do for my specific car.
Nonetheless, your car performed very well indeed.
May 25, 2003, 09:53 PM
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Originally posted by modvp
The WRX was a somewhat intimidated by the rather big gathering of EVO’s. I parked it far away though...looked a bit out of place.
The WRX was a somewhat intimidated by the rather big gathering of EVO’s. I parked it far away though...looked a bit out of place.
I agree, everyone was very cool. I thoroughly enjoyed the conversation and watching all the cars.
--Dan
Mach V Motorsports
MachEVO.com
May 26, 2003, 02:25 PM
#82
Hey guys, I have decided to remove my Vishnu 3" DP and Hi-Flo Cat in order to remain in stock class for Auto-X events. Installed it Friday night and removed it this morning. Only drove it to and from DynDay at Altered. Comes with cross bar spacers, clamp, and gasket as received from Vishnu. Anyone interested shoot me a PM.
May 27, 2003, 08:21 AM
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jfh,
Thanks for the compliments. I am definitely impressed with my cars performance. Your car with a baseline of 240 is pretty damn strong. I guess the weather has a lot to do with the performance day to day. Shiv made your curve nice and smooth. I bet a testpipe would have put you up in the mid 280's.
Thanks for the compliments. I am definitely impressed with my cars performance. Your car with a baseline of 240 is pretty damn strong. I guess the weather has a lot to do with the performance day to day. Shiv made your curve nice and smooth. I bet a testpipe would have put you up in the mid 280's.
May 27, 2003, 10:10 AM
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Originally posted by jfh
modvp - I'm glad that you came. I enjoyed talking with you. No need for the intidimation though, we are all car guys and just enjoy getting together. After you are settled into the new house and all the dust settles, the nexgen EVOs may may offer similar stock performance to those you are familiar with from the islands. By that time, you'll be able to sell the WRX if you are still inclined to do so. If that is your plan though, don't sink alot of money into the WRX that you will not recover at resale time.
Regards,
modvp - I'm glad that you came. I enjoyed talking with you. No need for the intidimation though, we are all car guys and just enjoy getting together. After you are settled into the new house and all the dust settles, the nexgen EVOs may may offer similar stock performance to those you are familiar with from the islands. By that time, you'll be able to sell the WRX if you are still inclined to do so. If that is your plan though, don't sink alot of money into the WRX that you will not recover at resale time.
Regards,
May 27, 2003, 08:08 PM
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Dyno update
Today I came back to Altered Atmosphere to get some parts installed and do some before and after dyno runs. We did three runs of the car stock (maybe 5 minutes between each run), then installed a catless Buschur intake right on the dyno and ran three more runs. Then the car came off and ran three more after installing a Buschur turbo-back exhaust
The dyno runs were fairly consistent, but still showed a 3-4 horsepower spread in the max HP and max torque figures, in each group. The baseline numbers were in the 223-225 HP range. After installing the intake, we got numbers in the 226-230 range. Finally, after the exhaust, it was up to 235-240 hp. (These numbers are all from memory; I could be a little off.)
The last pull made the 240 hp number, and that was dramatically better than the rest. I'm not sure exactly why.
I don't have the charts on me, but I'll post them here in the next day or two.
These were third gear pulls, rainy weather, maybe 70 degrees out.
I was surprised that the intake added so much power, because the airbox design looks very free-flowing to me. I was also surprised that the sewer-pipe-sized 3" exhaust didn't add more power, but if you look at the factory system, it's about the best I've ever seen. It's extremely straight, the bends are all wide open, the pipe is big-bore (2.25") for a stock system. Even the cat is about the freest-flow unit I've ever seen on a stock car. So, unlike the days when you could slap an open exhaust on a DSM and get 25-odd horsepower, the Mitsu engineers definitely built a good exhaust system.
I mentioned before that I'm guessing one source of different power levels on similar Evos was from boost differences. I was also thinking today about other possible explanations for different dyno results on similar cars. Other than different boost levels (I didn't have a boost gauge on this car for these runs), I also though of a couple of different possible sources of variance...
One is the tie-down straps on the Dynojet. These straps hold the car in place so it doesn't wander off the rollers. (They're important! Ask me how I know...) They are tightened fairly tight -- I'm not sure how much force they're under, but they're quite taut in order to hold the 3200-pound car in place. Figure a couple of hundred pounds of force each. Most of that force is in a sidways direction, but some of it is DOWN, squeezing the car onto the rollers. Depending on how tight the straps are, the car will get squashed onto the rollers a little bit. I was noticing the tires flex a little as the straps were tightened. If this tension varied from run to run, the rolling resistance would change. I have no idea how much effect this would have.
--Dan
Mach V
MachEVO.com
The dyno runs were fairly consistent, but still showed a 3-4 horsepower spread in the max HP and max torque figures, in each group. The baseline numbers were in the 223-225 HP range. After installing the intake, we got numbers in the 226-230 range. Finally, after the exhaust, it was up to 235-240 hp. (These numbers are all from memory; I could be a little off.)
The last pull made the 240 hp number, and that was dramatically better than the rest. I'm not sure exactly why.
I don't have the charts on me, but I'll post them here in the next day or two.
These were third gear pulls, rainy weather, maybe 70 degrees out.
I was surprised that the intake added so much power, because the airbox design looks very free-flowing to me. I was also surprised that the sewer-pipe-sized 3" exhaust didn't add more power, but if you look at the factory system, it's about the best I've ever seen. It's extremely straight, the bends are all wide open, the pipe is big-bore (2.25") for a stock system. Even the cat is about the freest-flow unit I've ever seen on a stock car. So, unlike the days when you could slap an open exhaust on a DSM and get 25-odd horsepower, the Mitsu engineers definitely built a good exhaust system.
I mentioned before that I'm guessing one source of different power levels on similar Evos was from boost differences. I was also thinking today about other possible explanations for different dyno results on similar cars. Other than different boost levels (I didn't have a boost gauge on this car for these runs), I also though of a couple of different possible sources of variance...
One is the tie-down straps on the Dynojet. These straps hold the car in place so it doesn't wander off the rollers. (They're important! Ask me how I know...) They are tightened fairly tight -- I'm not sure how much force they're under, but they're quite taut in order to hold the 3200-pound car in place. Figure a couple of hundred pounds of force each. Most of that force is in a sidways direction, but some of it is DOWN, squeezing the car onto the rollers. Depending on how tight the straps are, the car will get squashed onto the rollers a little bit. I was noticing the tires flex a little as the straps were tightened. If this tension varied from run to run, the rolling resistance would change. I have no idea how much effect this would have.
--Dan
Mach V
MachEVO.com
May 28, 2003, 07:26 AM
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I say go w/ engine management like XEDE or SAFC, etc and then you'll see a true improvement. The car is just way too rich from the factory.
I don't think the tie downs will have a large effect since the rollers are so massive... Evos tend to show large variance between car to car and some variance between run to run.
Can you post your stock dyno plot?
Mark
I don't think the tie downs will have a large effect since the rollers are so massive... Evos tend to show large variance between car to car and some variance between run to run.
Can you post your stock dyno plot?
Mark
May 28, 2003, 08:23 AM
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im going emanage =).... hey quick question dan.... remember when u busted out your sound clip recorder and recorded the turbo back buschur exhaust and u remember how it was very rattly... it sound the same on your car or less rattle? for my exhaust im most likely going to go hks downpipe/hks turbo exhaust.... but honestly my interest in exhaust is only half for performance... and the other half is the SOUND bcuz it will go with me everywhere i go no matter wat until i take it off which i probably never will... i want an exhaust that basically sounds JUST like our stock one but little bit louder when cruising.... and a dramatic increase a WOT... i dont want that rattle though i always hear on the WRX's w/ exhaust and the one we heard together on the white one i believe it was
May 28, 2003, 08:30 AM
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Dan,
How did the undercurve differ between the stock exhaust and the Buscher? Was it just peak #'s that were higher or was it higher everywhere throughout the rpm range? Also, did the car run richer with the Buscher T-back than the stock exhaust?
How did the undercurve differ between the stock exhaust and the Buscher? Was it just peak #'s that were higher or was it higher everywhere throughout the rpm range? Also, did the car run richer with the Buscher T-back than the stock exhaust?
May 29, 2003, 12:18 AM
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I don't yet have the charts in hand, so I can't answer the area under the curve thing.
At least at high rpms, it's pretty much impossible to figure out if it ran richer after installing the exhaust, since it drops off the a/f chart completely (richer than 10.0:1) above 5000 rpms or so.
--Dan
Mach V
At least at high rpms, it's pretty much impossible to figure out if it ran richer after installing the exhaust, since it drops off the a/f chart completely (richer than 10.0:1) above 5000 rpms or so.
--Dan
Mach V
May 29, 2003, 12:22 AM
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Originally posted by ChillinEvoVIII
hey quick question dan.... remember when u busted out your sound clip recorder and recorded the turbo back buschur exhaust and u remember how it was very rattly... it sound the same on your car or less rattle?
hey quick question dan.... remember when u busted out your sound clip recorder and recorded the turbo back buschur exhaust and u remember how it was very rattly... it sound the same on your car or less rattle?
Funny thing is, you can't hear that at all inside the car. At cruise it's really pretty quiet in the cabin.
But standing behind at idle, it reminds me of standing by the race track pits.
--Dan
Mach V
MachEVO.com
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