Akuma HT65 Stage 2 Turbo upgrade!

taf0422

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2007 Mazda Speed3 GT
Akuma HT65 Stage 2 Turbo!!

Pictures/dyno charts attached at bottom!!

Made 310hp 354tq today at IAG Performance..Spinning all over the place on the dyno..

Can't wait to see what she does when I have the actuator on there!

First I just want to say how professional Akuma has been from John to all the employees throughout this entire process. From answering my 100+ emails about the turbo in general about the turbo, down to wanting to know the progression the turbo has made. I have never felt like just a number or another guy coming up to the shop. I have put almost 800 miles on this turbo in 4 days! I dont want to get out of my car!

The HT65 Stage 2 turbo is finally here and ready to take some names!!! It has been about 9+weeks in the making and it has definitely been worth the wait. Every time that I get into the car it puts a smile on my face. Its really quite amazing what this turbo can do and Akuma has only scrapped the surface of what this turbo is capable of. It feels as though it has endless power, it pulls and pulls. It wants you to continue to throw higher boost levels at it. I have been royally impressed by what this turbo can achieve with still having the stock housing containing the custom machined billet wheel!! It is really a beautiful piece and defies the laws of physics when you notice how small the K04 is up close and personal with the power this turbo is capable of. I have absolutely nothing bad to say about the turbo.

This is a direct bolt up turbo. No messing with coolant/oil lines or trying to find additional ways to mount the turbo. No fabrication needed to get this bad boy to fall into place. When this turbo is on the car you will wish and wonder why it was not put on from the factory. When you want boost it is at your disposal!! 100% of the time. No waiting for boost lag or having to have the rpms in excess of 4500rpms to build the boost up. This will make you want to walk away from the stock turbo instantly and even the GT2871r turbo. This turbo spools a bit faster than a GT28 turbo but has comparable top end with supporting mods. It will hang with the big GT28 for torque all day. This is the perfect daily driver turbo for people who want that boost on demand but still want the drivability of the stock turbo. I have been on back roads, highways, hills anything you can think of with this turbo over the last few days and it has done nothing but exceed my expectations.

There has been no expense spared by Akuma to put this turbo together. The Stage 2 unit utilizes the latest in Extended Tip technology with a billet HTA wheel. Think better Aero, and 7 Blade versus the 6 Blade Aero of the K04. The Turbine is balanced and the aero refined for flow. This journal bearing upgraded 65mm Billet Compressor Wheel can be pushed well beyond the capabilities of the stock K04. This turbo will happily flow 40LBS/Min a reasonable pressure ratio. The idea here is to free up back pressure and use the proper supporting mods. An upgraded actuator(Akuma can offer a Forge unit) will help hold 19+ LBS up top for some great results.

When looking at the numbers this turbo is capable of with turbos in same hp number range it is really a no brainer. Just to compare some price numbers here a little bit a GT2871r and GT3071r are running in excess of $1700 not to mention all of the other things you are going to need to make it run correctly. The BNR stage 1, Stage 2, Stage 3 turbos are $950, $1100, and $1200. The Akuma HT65 stage 2 turbo is efficient up to around 25-26 psi and is going to be priced at $1000!! This will need no extra fittings or modifications. If you want to run much more than 18psi to redline, you may need to pick up an aftermarket wastegate actuator if your stock one starts to bleed off the boost toward redline like mine did. (I bought one yesterday! So I can run the 20-21 psi to redline! :) ) Right now the turbo is running 20 psi to around 5000rpm then starts to bleed off to about 18psi at redline because the actuator cant hold the boost. But holy crap this thing feels like it flies as is!! John is definitely an expert when it comes to tuning the Mazda and getting power out of these cars safely.

On an extremely loaded mustang dyno running in all-wheel drive mode. Looking at the before and after dynos and before the actuator is installed (wait for results on new actuator!) Before the turbo was installed I made 265 hp and 273 ft-lb on a completely maxed stock K04 running meth and after the Akuma turbo was installed I made 291 hp and 325 ft-lb. The turbo still gained me from the same dyno a few months prior 26 whp and 52 ft-lb. If you notice from the new turbo dyno chart the car really wants to continue to make power but because the boost starts to fall off it is a little difficult. This turbo will start to shine even more with someone who has a few more mods than I do.

This is only the beginning for this turbo. I am looking to keep the boost going to red line to increase the HP/TQ numbers!! I cant wait. Definitely ask all the questions you want and I will try to answer them the best way I can. I would definitely pull the trigger on this!! Akuma is ready to start continuing with these things!!! This thread is just to express my liking to this turbo, results and give guys an insight into whats really inside these turbos. At first glance this turbo should not make the power it does, but I assure you you will enjoy this turbo for a daily driver or weekend racer!


Side Note:
Right now John is also looking for a fully built motor, fully bolted, meth, bigger maf sensor Mazda Speed owner willing to upgrade to stock wastegate actuator to run the 2nd prototype turbo at 26 psi to really see what this turbo is made out of!! Im not quite there yet. lol
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View attachment sloms3-2.pdf

View attachment ms3 ht65.pdf



http://www.youtube.com/watch?v=OGnjiVGB6OI

http://www.youtube.com/watch?v=3R4xIla8nDY
 

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Also the car will be on the dyno jet for some numbers there as well at the IAG meet in west minister, MD this Saturday.

Hopefully I'll be able to get a retune with the new wastegate actuator to put up some bigger number in the next few days/week
 
WOW! Looks like he really knows how to rework the stock unit. The cheapest upgrades I've seen are around 1700 for a new garret, or other brand. So this literally just goes right back on the stock car and runs fine without a new manifold, DP or anything else? Does he have any cars running this long term with decent reliability? Does he offer you a core refund if you send him one, like Protege Garage does? How much tuning is necessary after the upgrade? And does anyone know how much safer this would be compared to an AP+necessary mods...because I'm looking at the AP+stage 2 mods costing MORE and hearing quite a few stories of blown motors.
 
He definitely did an amazing job with reworking the stock unit. The upgrade is definitely affordable compared to the other ones out there. I don't think this should be one of your first mods but yes it most certainly does just drop right in. You are not going to get all of the satisfaction it brings without all of the other stuff. You will need to have the car tuned/ATR after the turbo is put on.

My car is the very first one. I have the prototype turbo...so far about 800+ miles on her and still running just fine. He has another one waiting to go on a car that has a few more mods than I do such as maf upgrade/build motor. He wants to run 26 psi out of the turbo. He doesn't want to try it on my stock motor. I'm fully bolted right now. I have the new wastegate actuator waiting to be installed. Just don't know if I will be able to get it in/tuned by the Saturday so I'm just going to hold off on it until Tuesday of next week. I'm sure John at Akuma is willing to work with anyone on the core refund. I would just call him up. As of right now all I know is the cost is $1000. I'm unsure if that includes the core refund or not.
 
What other mods do you have? Was the 310 made after a full tune? How much boost?

You dont need these items to run the turbo obviously but my car is fully bolted, meth, and a full tune from akuma. The car makes the most hp towards the end of the power band thanks to Johns tuning...too bad the wastegate actuator is giving out. The HP will be much higher by the end of the week. I will have the new actuator on and a retune. We are looking for another atleast 30 hp more with just keeping the boost at 20-21 pounds of boost. As of right now boost hits targets then at 4700 rpm dies off to 18 psi. Way more to be had from the turbo especially if someone runs 26 psi where the turbo is still efficient.
 
I cant even say how appealing this looks...if only I had the extra $ layin around. It seems like it would just pick up where the stock unit fails, and go so much further, without needs for more mods, etc
 
I cant even say how appealing this looks...if only I had the extra $ layin around. It seems like it would just pick up where the stock unit fails, and go so much further, without needs for more mods, etc

John is currently trying to buy up some used K04 units to completely redo like he did my turbo to try to keep the costs down as much as he can. The reason for the price where it is now is all the technology is all brand new. It hasn't been tried inside of this turbo with the extended tip and 7 blades. This is the first one like it.

I hope this story has a happy ending. Just be careful, out there!

Everything is good to go. Everything has been tuned perfectly and the turbo is working great! And thank you. I will try my best. You as well.
 
Actually I don't see much of the difference with PG turbo, just the price is higher. PG rates its turbo to 23 psi of effective boost. From what I see, the hot side is stockish, may be with some port&polish. Compressor wheel is not bigger. This in total will not make it to flow 25 psi effectively.
Central cartridge is still K04, and the bearing are still KKK ones. So it may smoke as well as stock or PG does. Especially on 20psi or more.

Don't get me wrong, I'm not offensing, just don't see why it is better.
 
I will reply back to the message above when i finish up work. This turbo steps it up compared to PG turbo. Everything is made better and stronger. Everything is been machined out, ported, polished. 67mm wheel inside of the turbo all billet made just for this turbo no other turbo has this wheel sizing/billet wheel in their turbo. More to come later
 
Shall wait for your reply!
Also I'd like to know, how stiffer actuator would help you holding boost to redline. Even stock actuator can do this. Even 4psi actuator can do this, according to simple theory. This is solenoid and tune which makes it holding. The reason stock one goes down is actually the turbomap of K04, which forces high boost on high flow being not effective.
By the way, do you have turbomap for this turbo?
 
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Shall wait for your reply!
Also I'd like to know, how stiffer actuator would help you holding boost to redline. Even stock actuator can do this. Even 4psi actuator can do this, according to simple theory. This is solenoid and tune which makes it holding. The reason stock one goes down is actually the turbomap of K04, which forces high boost on high flow being not effective.
By the way, do you have turbomap for this turbo?

The stiffer wastegate will help with my application because we keep raising the targets on the load further up the scale and we get to a certain point and no matter what we do the car will not make anymore boost. My wastegate is completely maxed out at 99.89. This same discussion that I'm having with you now was beaten to death on the other forum. They have found out and did find out a little over a year ago that it was the wastegate actuator causing the problem. My car has a completely new map that was tuned from scratch for this turbo and the meth
 
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I am not arguing, just my experience... When I bent my rods, I had 1.53 bar (22 psi) of boost at about 5800 rpm :) I just don\t understand, how wastegate can be maxed if we have a solenoid which controls the boost. Just put off the vacuum line from the actuator nipple - and you'll have it stuck closed. The wastegate itself won't open by anycase, it's just the air pushing the actuator diaphragm which can do this. Actuator diaphragm air amount is controlled by ECU via solenoid or via manual BC, whatever.
Let me know where I am wrong, and I will be very sad, as the words above are just the basics of controlling the boost. My english is not so good so I could have chosen some incorrect words, but in general...
 
Really interested in seeing how this works out. Having more options is always good. Any word on when he's going to start taking orders and what the final price is?
 
Really interested in seeing how this works out. Having more options is always good. Any word on when he's going to start taking orders and what the final price is?

He is starting to take orders now. Just give him a call at 732-970-9009 and ask for John, he will give you all of the details involved in this easy swap.

I would have had the new wastegate installed but I've been having some family issues that kind of over look the car right now. I have all pieces and a new map to go along with this wastegate. The 1st of a few revisions to get this bad boy dialed in over some emails.
 
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