Don't be too impressed by the numbers. Remember that these numbers have a 1.14 CF, which is what we use to sort of account for the 6800' of altitude, so my uncorrected numbers are a meager 284whp/305wtq. It's an attempt to mimic sea level numbers without using the full crazy correction (1.28-1.30) that the computer wants to use. The torque is still nice, but that's what you get with big boost and alky.

My gauge was reading 30psi, but the atmospheric pressure up here is much lower, so my gauge usually reads about 4psi higher than absolute manifold pressure. So, that's why I was pretty sure I was hitting 26psi even though the dyno's MAP sensor only said 21psi. Not sure if there was a leak at the tee or what. Anyway, since I made 371wtq on the last run after cranking boost, I'm sure the boost was higher than 21psi, and that's why I turned it back down to where I felt comfortable, which is the 324whp/348wtq setting.

Yes, 100% denatured alky.

I see no change in driveability. The spool may be slightly slower, but I can't tell, and I haven't noticed a change in part throttle response. I don't expect it to be much different, since I kept the ported/coated hotside from my 05, so the only change really is the compressor housing. I've only driven it since Friday, and most of that time was spent on track. It felt great the whole weekend...

1) Thanks. 2) It's not better - the IX turbo usually spools a little slower compared to the VIII. I can't feel any difference so far, though. 3) Good question, but I think I answered that in the first post. The first run back in July, we couldn't get a good RPM reading, and when that happens, you don't get a good torque graph and can't put RPM on the x-axis. You have to use speed (MPH) and can only show WHP (no WTQ), then I put boost on the graph for later info. I didn't do my new runs on MPH without torque, because I wanted a proper graph. So, during this next week, I'll have them do a layover of the new and old WHP graphs on the MPH axis to at least show a direct comparison, although no torque.

 

Two reason: 1) I'm a cheap bastard, and 2) I am limited to an 8.7:1 weight/hp ratio in my NASA time trial class (TTS), and we are forced to use SAE correction. So, wherever I race, which will include high altitude and low altitude, I can't go over 385whp SAE corrected on a Dynojet, or I'll be bumped to the next class. I figure my setup with the IX turbo should be close to 385whp on a Dynojet at sea level. Maybe with the 20g-LT, I could make more power max then turn it down for races, but I am content to drive it in the same mode all the time pretty much.

1) We are at extreme elevation (6800'), so we typically use a correction factor to account for that altitude. I personally don't care and prefer uncorrected numbers, but for NASA time trials, I had to have a certified dyno sheet using SAE. The auto-calculated SAE for Friday evening was 1.28, which put me at 363.52, which would be divided into 3350lbs to get 9.21:1 weight/hp ratio. My limit is 8.7:1, so I'm good. Well, for F/I cars, we prefer to cut the standard CF in half, since we know F/I (or at least turbo'd) cars don't lose as much power to altitude. That's why you see me using 1.14 (half of 1.28).
2) If no CF, then I make a raw 284whp/305wtq on this DD at this altitude. Weaksauce.
3) Just like any dyno with any correction factor - the numbers change, because you multiply the uncorrected numbers by the CF, and the CF changes according to the barometric pressure, temps, humidity, etc.
4) Not sure what you mean - there was no change from 1.3 to 1.14.

As mentioned by others, I did swap to a built Shep 5spd after ripping the teeth off 4th gear in the 6spd. I wanted to continue road racing regularly, so Shep recommended ditching the 6spd for a 5spd. AMS uses his 5spd trannies in their time attack cars, so that was enough for me. After racing this whole weekend without the slightest hint of hiccup in relation to the clutch/trans, I think I made a great choice.

Unfortunately, though, since I found that the IX turbo tapers just the same and 4th dies out after 6400rpm, I may still end up shifting to 5th up here, albeit later down the track. On the 6spd, I was shifting to 5th before the 1000'!

 

Any challenges on the install? Simple bolt on, right?

 

It was straightforward, but that's because I made sure to get all the little parts that are specific to the IX turbo that don't fit the VIII turbo: wga, compressor outlet pipe, and oil/coolant lines. The seller had his work done at AMS, and AMS sent me the whole turbo assembly in one piece, which made everything easy. The only curve ball was that I took the ported/coated 10.5 hotside off my VIII and put it on the IX.

 

Yeah that 1 v-band clamp can be a real pain! =p


Good stuff Clay.

 

Yeah, this thread is giving me hope for the IX turbo swap I want to do, but the elevation here in ABQ isn't much better. Boo to elevation!

 

What I showed is that you can get the same gains at elevation as at sea level. It's not about the raw numbers as much as it is the gains...

 

Very interesting stuff, thanks for posting it up. I'm looking even more forward to my IX turbo swap now. I'll have similar setup but without alky and on stock ic. So if Evo IX's consistently post ~30 more whp than VIII's, I wonder if we could assume from this test that the turbo comprises 20hp and MIVEC comes up with the extra 10hp (plus spool)...

 

We had pretty much come to that conclusion a while ago. I'm just another example that supports the argument.