WRX USA's 09 OBXT Build Thread

Did you have to source a different hose to connect to the killerB waterpump housing?

No, I'm using the stock hose with the stock radiator. They had to use studs to install it because the bolts that were included didn't fit. I understand KillerB does include the right hardware now.

At this stage, how would you compare the OBXT's handling to say the WRX or other rides? You've obviously got significant ride height and suspension travel, but you've invested heavily in stiffening up the suspension too and you are riding on some decent all season tires. Very curious

Would really welcome your input on just the overall driving experience from an enthusiast with a history in the WRX.

At this stage, how would you compare the OBXT's handling to say the WRX or other rides? You've obviously got significant ride height and suspension travel, but you've invested heavily in stiffening up the suspension too and you are riding on some decent all season tires. Very curious

 

Would really welcome your input on just the overall driving experience from an enthusiast with a history in the WRX.

There is no doubt that the handling is much sharper on my WRX versus my OBXT just given the ride height and tire profile. The stock OBXT handling for me coming from the WRX was recklessly bad. RSB helped a ton but the BTS-5056 made the car way more enjoyable and completely comfortable. The only thing that sucks after that is the steering rack. You don't realize how much turning you are doing until you get an LGT one. With the addition of the 6MT that car is perfectly set up as a DD that is a blast on a mountain road or a 2000 mile road trip.

I just got my car back from GST Motorsports today, after they installed these parts and did a dyno tune.

- JMP Custom VF52 with TurboSmart IWG-75

- HKS Premium Suction Kit (powdercoated satin black)

- IAG TGV Deletes

- ID1000's

- DW300c

- KillerB Holy Header (ceramic coated)

- Company23 Anti-Surge EBCS

- TurboSmart BPV

288hp/301tq (up from previous 234hp/278tq)

Base run = VF46, stock everything else except Maddad catted DP and Nameless CBE with 5" mufflers

Test run = everything in the install list above and GS TMIC

http://i672.photobucket.com/albums/vv87/JoshEAllen/BB54CF76-9A38-41F9-966A-7907738E6A98.jpg

http://i672.photobucket.com/albums/vv87/JoshEAllen/F074EFDE-9E90-4074-BB5A-41560668E5C9.jpg

There is no doubt that the handling is much sharper on my WRX versus my OBXT just given the ride height and tire profile. The stock OBXT handling for me coming from the WRX was recklessly bad. RSB helped a ton but the BTS-5056 made the car way more enjoyable and completely comfortable. The only thing that sucks after that is the steering rack. You don't realize how much turning you are doing until you get an LGT one. With the addition of the 6MT that car is perfectly set up as a DD that is a blast on a mountain road or a 2000 mile road trip.

 

I just got my car back from GST Motorsports today, after they installed these parts and did a dyno tune.

 

- JMP Custom VF52 with TurboSmart IWG-75

- HKS Premium Suction Kit (powdercoated satin black)

- IAG TGV Deletes

- ID1000's

- DW300c

- KillerB Holy Header (ceramic coated)

- Company23 Anti-Surge EBCS

- TurboSmart BPV

 

288hp/301tq (up from previous 234hp/278tq)

That must be a blast - very nice selection of parts!

Does the Company23 EBCS eliminate wastegate flutter like it advertises?

That must be a blast - very nice selection of parts!

 

Does the Company23 EBCS eliminate wastegate flutter like it advertises?

I also had a Grimmspeed with me when I dropped my car and I asked my tuner if he thought it was a gimmick. He thought it really worked so that is why I went ahead with installing it (vs. selling it). I need do more driving before I have an opinion.

First off, great results.

I'm surprised at the loss of torque/hp from ~2400-3500rpms. If I was solely looking at your dyno chart, I would expect that you moved to a much larger turbo since it takes an additional ~1000rpms for you to reach the torque output of the vf46 (on the chart).

I know dynos can often mis-lead, especially in the early RPMs, just jumped out at me as the vf52 is typically considered a very minor sacrifice in lag in order to gain a significant mid-range and top-end boost.

First off, great results.

 

I'm surprised at the loss of torque/hp from ~2400-3500rpms. If I was solely looking at your dyno chart, I would expect that you moved to a much larger turbo since it takes an additional ~1000rpms for you to reach the torque output of the vf46 (on the chart).

 

I know dynos can often mis-lead, especially in the early RPMs, just jumped out at me as the vf52 is typically considered a very minor sacrifice in lag in order to gain a significant mid-range and top-end boost.

My feeling from moving to a VF46 to a VF52 was similar. I don't have any dyno runs to compare to. But my gut feeling was that the 52s torque (the hit) was a lot later in the power band.

First off, great results.

 

I'm surprised at the loss of torque/hp from ~2400-3500rpms. If I was solely looking at your dyno chart, I would expect that you moved to a much larger turbo since it takes an additional ~1000rpms for you to reach the torque output of the vf46 (on the chart).

 

I know dynos can often mis-lead, especially in the early RPMs, just jumped out at me as the vf52 is typically considered a very minor sacrifice in lag in order to gain a significant mid-range and top-end boost.

When I received this turbo, it had extensive port work done on it. EVERYTHING was opened up on it, When port work is done on turbos, it has to be a very finite line between enough and too much and unfortunately, most of the porting I see (in my own opinion and without a flow bench at my disposal, I can't be sure, but just from visual inspection) is way over the top but it looks cool.

My experience when I do the upgrades/rebuild/custom work on the ported turbos is their powerbands are all over the place versus the OE non-ported units. WHP is a number and so is torque but it's WHEN you reach those numbers that is important. If you're on a racetrack and always at 4000+ rpm, then you need that big breathing/flowing piece to always stay in the middle of the big spool, but in real world driving when you are going across an intersection and a semi is coming at your driver's door without stopping, you need SPOOL and you need it NOW!

I learned many years ago in 2 stroke go karts and racing dirt bikes, if you want to take cylinder that works pretty well and destroy it, port it. There are a few cases where huge port work is necessary, but any of the IHI models we all use are not large enough to do it.

The other myth is that to make everything smooth inside helps the flow. I have a friend that works at Roush-Yates Racing and he does head port work and they always leave a pebble grain finish inside when they are done. His explanation in laymen's terms to me is as follows:

"Have you ever seen a smooth golf ball? It's been tried and they go 60-70 yards and fly all over the place. Add the dimples and they fly 5X farther and that's because of the swirl pattern of the air".

Makes sense to me, so I don't smooth out much anymore and I've seen the best results from just cleaning but not polishing.

Anyway, my 2 cents.

This talk about vf52 lag makes me feel better (sorry?). Have been worried about TS VF52 with a billet compressor wheel. Was afraid it would hit too early due to billet and TS.

While not a transient dyno test, the other day I tried testing boost onset with my non-ported, regular old VF52 up a hill in a high gear. I hit 18 PSI at 2400 RPM.

The addition of the grimmspeed intercooler will increase lag when compared to a stock intercooler as well, as there is a greater volume post turbo to pressurize. The headers add another unknown, but as JmP posted - the porting probably has the greatest effect on the lesser boost at low RPM. <- applies to transients, not what will be seen on the dyno.

Also, just to be clear - those headers and intercooler are top of the line and I'd love to have them on my car.

WRXUSA, guys,

porting VF turbo does very little if anything - waste of money, really -

no dyno data to support it, anywhere.

If anything, you want a A/R restrictor to spool-up faster, but then you'll pay a penalty on the top end, so there is no point really. Since there is no way to change the actual A/R ratio up by porting just the entrance port its pointless. Excessive porting will cause turbulence down the snail and actually hurt you.

Mike@GST does a wonderful job tuning VF52 on e85 - this cures 85% of the lag.

for what its worth I am speaking from experience.

OP, how does the obxt rear suspension behave now, when you go over a speed bump at like 15 mph or something? I basically want to know if you get a 'double bounce' as we're getting with the crappy kyb shocks...

Second question, say you're entering the freeway. Assume the freeway entrance has a nice curve to it, and there is an uneven section on the road where only the right side of your car will hit it for instance resulting in medium suspension travel. How confident would you be going over such section?

Finally when there is excessive suspension travel for whatever reason at medium speed, do you still feel this ghostwalking effect due to our rear suspension geometry?

OP, how does the obxt rear suspension behave now, when you go over a speed bump at like 15 mph or something? I basically want to know if you get a 'double bounce' as we're getting with the crappy kyb shocks...

 

Second question, say you're entering the freeway. Assume the freeway entrance has a nice curve to it, and there is an uneven section on the road where only the right side of your car will hit it for instance resulting in medium suspension travel. How confident would you be going over such section?

 

Finally when there is excessive suspension travel for whatever reason at medium speed, do you still feel this ghostwalking effect due to our rear suspension geometry?

I don't think there is a "double bounce" like you describe but I can seek out some speed bumps to confirm.

I have 100% confidence in the suspension, with all of the changes

Zero ghostwalking. I just got back from a camping trip with my dog and the back was completely full (I went from a 3 finger gap in the rear to 2 fingers) and over the 500 mile drive it never felt weird.

I see. Thanks for the info. Yeah, interesting to hear how yours behave on a speed bump at like 15-25mph. BTW, I am referring to those fairly large/long speed bumps, not those super short and abrupt ones.

If the BTS kit is anything like my HDs I can take them at about 30 with out any drama. I actually speed up for the fairly large/long ones (wait what are we talking about?)

If the BTS kit is anything like my HDs I can take them at about 30 with out any drama. I actually speed up for the fairly large/long ones (wait what are we talking about?)

With my HD/pink spring set up on the 06, I definitely cannot take speed bump above like 15mph. Way too harsh. But I see what you're saying..

I should add that my 05 (with stock KYB struts and rallitek overload springs in the rear) is getting a double bounce also probably due to the fact that I am constantly carrying a bunch of stuff in my trunk :/ (3.5 cu ft/120lbs subwoofer box, crafstman toolbox, a bunch of extra tools in case I get stranded, amplifiers, etc...) All in all, I think I am lugging around easily 200+ lbs of stuff in the trunk on a regular basis. So that's probably why...

Exterior changes have started.

http://i672.photobucket.com/albums/vv87/JoshEAllen/59B942C9-4EFC-4959-91A8-DB153A37BA97.jpg

JDM mirror garnishes installed

Liberal wing or MachV wing? Looks great! When I'm back in CA ID love to get our wagons together for some pictures.

Thanks, it's the Liberal! Hit me up when you get back and we can definitely meet up for some pics.

OP when you installed the bts kit, did you add any spacers? Almost looks like you kept the OEM ride height.

No spacers. It's about an inch lower than USDM OEM.