I installed the AP-X on my car back in Sept and had it mostly setup but never got a chance to tweak it to the way I wanted it until recently because work was very busy. I ran into a few minor issues because I either changed my mind or was being picky about the setup, but nothing major. Over all it was very easy. I've had turbo hondas, Twin turbo Rx-7's, Supra's and a 350z with the Greddy Twin turbo kit This kit is easy to install as a kit for a four banger honda (pretty easy)
Things I changed:
Went to Electronic boost controller vs Manual because I didn't like the way boost tapered off after it hit full boost. It's a small amount (.5psi) but I just wanted full boost to redline. Plus it's nice not to have to mess with the boost controller when the tempature changes.
Turned off the Meth Injection. My filter for the meth kit clogged two or three times. I caught it everytime because I always keep one eye on the AFR read out. To me for the amount of boost I'm running it was more of a hassle then it was worth.
Once I removed the meth out of the equation it was clear the stock fuel pump was maxed out. I like to see 11.0 to 11.5 when I have more then 3 psi of boost. It would slowly creep up to 12.4 by redliine. It's not a huge deal but it's not the idea situation. Not to mention a walbro 255 is only 99 bucks. It's a no brainer. With that installed I can maintain 11.0 to redline. I will say the 440's are to small for a NSX running 8psi. You should shoot for a max of 85% duty cycle in a perfect world. Mine are maxed out at 99% at red line. 550's would be the better choice. Do the 440's work? Yes, all day long, however the 550's cost the same and you can still maintain 14.7 at idle so why wouldn't you?
I also mounted a 8' spal fan on the intercooler. Other people haven't had a issue with this but when I first started dyno'ing at 8psi my IC would heat soak and the power dropped by 20-30 hp even with the meth injection on. It was a very hot day (95f) and on the dyno there is no really good way to get a fan in there for flow. I added the fan though on the street I don't think it makes much of a difference at all most the time.
I get a few question about the setup fairly often so I figure others have the same questions and I'll share my opinions on them.
Upgrading the turbo.
This comes up a lot. The turbo that comes with the kit is a custom turbo that Wil says is a T-67 size turbo with specs he picked after much testing. Does it do the job? Yep. Can you get a better turbo? Of course! Will the difference be worth it on a stock bottom ended NSX? Not in my opinion.
A Garrert GT series turbo thats the correct size will run you 1600 to 1900 bucks. (ATPturbo.com) what do you get for the money? More HP? Nope, your factory bottom end holds you back there. Will it spool faster? Yes! I'm guessing 500rpms or so. Currently I see full boost by 4200-4400 rpm. I haven't seen good back to back data on this yet. So is it worth it? Completely up to you.
Upgrading the Intercooler.
As I said above on a dyno there isn't enough flow to carry away the heat from the intercooler. On the street with boost events being relatively short
(15-30 seconds) and widely spaced it works. If I was going to a road track or built the bottom end then I'd upgrade to a air/water in a minute.
Upgrading the Headers.
Once again if you have the 97 and up style that are true headers you'll probably get a bit quicker spool up with aftermarket but you can't use the extra power on a stock bottom end. Once you go built, heck yes. The factory ones a durable and fit perfect. The nicer headers fit well and rarely have a problem, but they cost at least a grand.
So whats the end result?
2 pulls at 8 psi and 1 at 6psi. This was on a 224 dynojet. There is less of a load on the motor with this type of dyno because the car weighs more then the rollers. So my boost was a little low (7.85 psi) but it paints the picture well enough. Also its hard to see but my AFR is around 11.2 most the run. There is more HP available with less fuel but it's not worth it to me on a factory NA car with a turbo kit on it. If you read all of this I hope it helps the people out there that wanted to know more before they took the leap.
Things I changed:
Went to Electronic boost controller vs Manual because I didn't like the way boost tapered off after it hit full boost. It's a small amount (.5psi) but I just wanted full boost to redline. Plus it's nice not to have to mess with the boost controller when the tempature changes.
Turned off the Meth Injection. My filter for the meth kit clogged two or three times. I caught it everytime because I always keep one eye on the AFR read out. To me for the amount of boost I'm running it was more of a hassle then it was worth.
Once I removed the meth out of the equation it was clear the stock fuel pump was maxed out. I like to see 11.0 to 11.5 when I have more then 3 psi of boost. It would slowly creep up to 12.4 by redliine. It's not a huge deal but it's not the idea situation. Not to mention a walbro 255 is only 99 bucks. It's a no brainer. With that installed I can maintain 11.0 to redline. I will say the 440's are to small for a NSX running 8psi. You should shoot for a max of 85% duty cycle in a perfect world. Mine are maxed out at 99% at red line. 550's would be the better choice. Do the 440's work? Yes, all day long, however the 550's cost the same and you can still maintain 14.7 at idle so why wouldn't you?
I also mounted a 8' spal fan on the intercooler. Other people haven't had a issue with this but when I first started dyno'ing at 8psi my IC would heat soak and the power dropped by 20-30 hp even with the meth injection on. It was a very hot day (95f) and on the dyno there is no really good way to get a fan in there for flow. I added the fan though on the street I don't think it makes much of a difference at all most the time.
I get a few question about the setup fairly often so I figure others have the same questions and I'll share my opinions on them.
Upgrading the turbo.
This comes up a lot. The turbo that comes with the kit is a custom turbo that Wil says is a T-67 size turbo with specs he picked after much testing. Does it do the job? Yep. Can you get a better turbo? Of course! Will the difference be worth it on a stock bottom ended NSX? Not in my opinion.
A Garrert GT series turbo thats the correct size will run you 1600 to 1900 bucks. (ATPturbo.com) what do you get for the money? More HP? Nope, your factory bottom end holds you back there. Will it spool faster? Yes! I'm guessing 500rpms or so. Currently I see full boost by 4200-4400 rpm. I haven't seen good back to back data on this yet. So is it worth it? Completely up to you.
Upgrading the Intercooler.
As I said above on a dyno there isn't enough flow to carry away the heat from the intercooler. On the street with boost events being relatively short
(15-30 seconds) and widely spaced it works. If I was going to a road track or built the bottom end then I'd upgrade to a air/water in a minute.
Upgrading the Headers.
Once again if you have the 97 and up style that are true headers you'll probably get a bit quicker spool up with aftermarket but you can't use the extra power on a stock bottom end. Once you go built, heck yes. The factory ones a durable and fit perfect. The nicer headers fit well and rarely have a problem, but they cost at least a grand.
So whats the end result?
2 pulls at 8 psi and 1 at 6psi. This was on a 224 dynojet. There is less of a load on the motor with this type of dyno because the car weighs more then the rollers. So my boost was a little low (7.85 psi) but it paints the picture well enough. Also its hard to see but my AFR is around 11.2 most the run. There is more HP available with less fuel but it's not worth it to me on a factory NA car with a turbo kit on it. If you read all of this I hope it helps the people out there that wanted to know more before they took the leap.
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