I have been to lazey every time I think about my time slips to go grab them, but my best time now is 13.5 at 100.09. So I keep improving little by little. But I am really looking for something to get me into the 12's. The mods I have added from the 13.632 run to the 13.5 run was the intercooler sprayer, which I was not using to its full effect because I only sprayed the IC down for about 10 seconds just as I staged. I plan on hooking it into my UTEC or getting the Turbo XS shifter with the push button on top.
But after all that I also added the Turbo XS Top Mount Intercooler. It feels faster now too, but I have not been to the track with it yet. I am still wondering how I can keep my boost pressure more constant with the UTEC in 1st and 2nd gear. This is what is happening now.
1st 12psi at most (14peak)
2nd 14psi at most (16 peak)
3rd 17psi at WOT (19 peak)
4th and 5th 18psi (may flutter to 20 at most)
How can I level that out so I am more like 15psi in 1st gear, and 17 or 18 in every other? It seems I can keep turning the boost up with the little bleader the UTEC Delta comes with but it does not change the top top end of the boost in 4th or 5th. But it may be bringing up the boost in 1-3rd. I am just too afraid to move it more than 2 turns or so. Tell me if I should.
My goal is 12's What do I need more than this list:
Helix Down Pipe
Magnaflow DP Back (no cats in system)
Utec Delta
Turbo XS TMIC
Turbo XS Intake
Turbo XS BOV (recirc)
Apexi Cold Air Box
CryO2 Intercooler Sprayer
The best thing you can do to get the most out of yoursetup at this point is to get your UTEC professionaly tuned. Stock maps just aren't going to get you there. THe stock wrx turbo / injectors are _barely_ capapble of gettting the car into the 12's anyway. I have an upgraded turbo and my injectors are _maxxed_ when i'm running my full boost map.
Tuning is the key to making these cars really fast. Your car has better fuel injectors than mine, so you have quite a bit more room there, but the stock turbo on the wrx is only efficient in a very narrow power band, it won't make boost below 3000 rpms, and runs out of steam above 5500, that's pretty narrow. Invest in a cheap STI turbo or an 18G upgrade, will make your life and tuning the car much easier, this is however, just my opinion, and not necessary to reach 12's. I just think the stock wrx turbo is really hard to drive and tune.
THe WRX is designed for the 'stepped' boost you are seeing. First of all, it's one of the way to keep from ripping your transmission out, the lower gears produce a bit less boost, thus lowering the strain on the drivetrain. Most trannies die boecuase people are 'flat shifting' them or running anit-lag off the line. Second of all, the boost stepping is a function of the top-mount intercooler. The vehicle monitors intake and exhaust gas temperatures and varies boost depending on the intercoolers efficiency. Being a top-mount, the intercooler is only efficient while the vehicle is in motion. Actually, at slow speeds, intercoolers are useless (because they pull heat off the engine, or off the pavement, or simply don't actually 'lower' the temp any beacuse there is not enough airflow), this is much more prevailant in our top-mount setup. So the boost has to be kept lower untill there is enough airflow over the intercooler to support higher boost. The higher gear you are in, the faster you are going, the more air you are moving through the intercooler.
The upgraded top mount will help, and the cryo2 sprayer will definately help, but you are never going to get rid of the 'stepped' boost, it's simply part of the way these cars run, which is why companies like TURBOXS leave the 'stepped' boost in the aftermarket units. A professional tune can really minimise the effects of this, but it's always going to make more boost the faster you go. All turbo cars do this, it just seems to be much more pronounced in ours.
As for getting into the 12's, you get a custom tune on that Delta unit, and get your 60 ft times into the 1.7's, and you will be running 12's no problem. Good Luck.
squidz, you should note that the stock turbo is too small to hold max boost through higher RPMs. Mine for example runs mid 16s but then has to back off considerably as RPMs increase. It's too small to hold the boost all the way up.
squidz, you should note that the stock turbo is too small to hold max boost through higher RPMs. Mine for example runs mid 16s but then has to back off considerably as RPMs increase. It's too small to hold the boost all the way up.
Most certainly...It just runs out of steam at higher rpms. It's a great mid-range turbo, but not really designed for high-horsepower applications.
I agree I think I need a bigger turbo. I am trying to find a used STI turbo, anyone know of one? Is it the VF39 or the VF43 I am looking for? I have been raicing for a long time, this just happens to be my first Subaru and I love it. It is way too much fun to drive. But My goal is some sort of 12's than I will be happy. Very drivable and fun to mess with Vetts and Mustangs.
Thanks for all your support. I know 12s are not all that fast, but good enough to be very respectable. If anyone can hook me up with a good price on a STI turbo let me know.
ok, not to steal his thread, but this one seems to have had good response, I know for his application, the vf-39 or 16 or 18g would great, for drag racing, but how about for autocross applications, which really as far as my experience, are mostly mid range second gear races, so, since the td04 has an insanely fast spool time, it is perfect for this application, correct? But, then again, I know I have a hard time beating STi's at autocross events, although it has been done(but only due to bad driving on their parts), they have the vf-39, but also six gears, so, does that make a huge difference. My main query here is the issue of lag and spool time, I know the vf-39 can produce larger numbers on a dyno, but on the ground gruntin' out an autoX lap, would it be more beneficial to keep my td04 with a higher boost level(max boost I have ever seen during an autoX was 15-16psi, but only for a second before I had to break and bank again), or should I upgrade to the vf-39 or some other turbo application?
once again, not trying to be a thread robber, just figured this would fit in alongside in this post.
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Matthew
Wow, it can turn well too?
that's a good question and one I've been pondering myself as I debate turbo upgrades. I personally could care less what number it puts down at the dyno, I want fast spool and performance throughout the power band. From looking at my dyno charts more carefully in comparson with other larger turbos (I use the TD04), I am of the oppinion now that it's just too damn small. Yes, it does spool fast (although it still has lag, I wouldn't say insanely fast) but it really really gets choked at the high end. To maximize "area under the curve" you probably want about the quickest spooling turbo you can get but also one that won't choke itself past 4500RPMs. What turbo is that? I'll get back to you.
EDIT: Oh, and if you're serious about AUTO-X, changing turbos puts you in a whole nother class so you'll likely want to keep it stock or else be competing against folks with a lot more than just turbo swaps.
that's a good question and one I've been pondering myself as I debate turbo upgrades. I personally could care less what number it puts down at the dyno, I want fast spool and performance throughout the power band. From looking at my dyno charts more carefully in comparson with other larger turbos (I use the TD04), I am of the oppinion now that it's just too damn small. Yes, it does spool fast (although it still has lag, I wouldn't say insanely fast) but it really really gets choked at the high end. To maximize "area under the curve" you probably want about the quickest spooling turbo you can get but also one that won't choke itself past 4500RPMs. What turbo is that? I'll get back to you.
EDIT: Oh, and if you're serious about AUTO-X, changing turbos puts you in a whole nother class so you'll likely want to keep it stock or else be competing against folks with a lot more than just turbo swaps.
Remember also that changing boost settings puts you in higher classes in auto-x as well, even if you have the same turbo. If you are already running Street Mod (I run in the same class), then you can pretty much do whatever you want.
mosc brings up a very good point, even though the TD04 spools well, and has good midrange, it's the area under the boost curve that you need to concern yourself with. The TD04 is a VERY small turbo, and even in it's sweet sopt, never runs abover 80-85% compressor efficiency because of the heat levels in the boxer engines. You could spend quite a bit of money on intercoolers and cryo sprayers to make it more efficient, but it's not the best soloution. For less money, you can find a turbo that has a much better boost curve and will provide you with better power. There are a lot of turbos out there that spool as fast as the TD04 and provide more airflow in the same rpm ranges, as well as having the efficiency to pull all the way to redline.
I don't think anyone can say 'this is the perfect turbo for you'...it's all very dependant on what you want the car to do and how you drive it. I drive very aggresively, i like the car to put a lot of power to the ground so i can steer with the trottle more, some people use less throttle input and have learned to modulate the steering and brakes to get the car to do what they want it to do. Just two different driving styles, one isn't better than the other, but each style has a turbo that will work well for you.
The good news is that we have a seemingly endless supply of turbo choices for these cars...or maybe that's the problem.
I think a VF-39 is perfect for what I am trying to do. Gives me quck spool times and just a ton better performance. If I really was worried about spool times and big HP numbers I would get a GT series ball bearing turbo.
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