May i say that latest update was a well written story. Glad you are back on track. Love yoyr writing technique and of course your build

 

Everything looks well thought out and fits perfectly on this car. Great job, taking cues from this build to apply to mine.

 

this thread has given me alot of motivation to start mine just sucks i was told harness was plug and play until 01 and read here it was upto 00 so thats a minor setback.. question what trans did you use stock 300 or the tt one

 

I'm glad you're finding the thread useful. I was hopeful it would be something those that have come after me find value in, just as I found so much information here from those that came before me. As far as having an 01- not a huge deal. Plenty of people have done the swap on 01+ models. A few early 01s actually are just the same as 98-00. The MAF plug is the tell-tale sign if I remember correctly. I am using the A340e transmission that came with the GTE motor from the Aristo. It's a bit stronger than the stock GS transmission and since I swapped over to the Aristo ECU, is compatible.

 

I'm not sure if it's Covid or something else. But the car WAS down for 4 months and it just didn't feel that long. The good news is that it isn't any longer! More on that later. We'll pick up where we left off, just ~2 brief months ago...

So waterneck saga continued. "Seller" "fixed" the leaky port. I put it on the car, and filled it up with coolant. Sans intercooler piping or exhaust connected, I started the car long enough to back it on of my garage and directly onto the trailer to take to a fabrication shop to have aforementioned piping built. I literally drove to his shop, got a quote, and brought the car back home. Upon returning home and unloading the car it sat again in the garage for a week or so until at which time while I was fiddling with something else, I found that the OTHER outlet weld was leaking. Great. Done with "seller." I try to give people the benefit of the doubt, but I bought this item off a legitimate forum, from a known member and paid a price commensurate with the part being functional. Moving on. Sent to my local fabricator in advance of me bringing him the entire car so he could fix it up for me in hopes I could minimize further fills, drains, and refills of the coolant system. Upon sanding down the aluminum, he said he saw sparks starting to fly. It appears whatever boob "modified" the waterneck didn't actually remove the steel nipples from the aluminum housing, thus Leaky McLeakerson. He repaired it and sent back.



The other thing that I've been wrestling with is where to go with the fuel in terms of "more." The turbo and engine are both capable of more than the transmission can handle, so I felt like if I could get the fuel up to snuff to basically be comparable to what the transmission could handle, this would be a good intermediate step. I have a Walboro 255 fuel pump, which will probably outflow what the stock 440 injectors can handle. However, I have some 1,000cc injectors on the shelf - cleaned and tested - ready to go in. But I didn't want to do fuel and turbo at the same time to avoid tuning / troubleshooting woes. So I picked up the biggest pump that I'm aware fits the stock Aristo hanger - an Aeromotive 340lph stealth pump and wired it up:


Off to the fabricator & tuner.

I found a fantastic resource in the central Arkansas area. He's about 3 hours from me, but he does fantastic work and it's worth the drive.

First order of business was chopping off the 45 degree elbow that had the intercooler outlet from the turbo directed into the frame rail. Welded on a 3" aluminum 90 degree elbow in it's place.

Next was the customization of intercooler piping that would run from the turbo intercooler outlet to the existing intercooler piping that supported the twins. He did a great job of putting this together - and he welded on the BOV flange.


Then down to the exhaust. No pictures here, but 3" downpipe all the way through to the Y-Pipe of my Tanabe Medallion catback. I was really shocked to find that under cruise and idle, the exhaust did not get any louder than it was with the stock Aristo exhaust.

So initial impressions:
The turbo and wastegate are much louder than the stock twins. I've never owned an externally wastegated car before, or one with this big of a turbo. I have the wastegate springs set at 7 lbs. The car spools and pulls better on low boost (I see boost at around 8-9psi - raises to 11.5 at the top of 3rd gear) than the twins did in parallel mode. It makes far better noises too!

The power delivery is great. I have the quick spool valve directly hooked up to boost source, so it opens up around 5psi. This seems to be spooling the turbo well. It's difficult in an automatic to see where the spool is starting or where full boost is at lower RPM, but I can easily spool it under 3k RPM. I usually start my logs a little over 3k rpm (to avoid kick down). About 1.5 seconds later (with 7lb wastegate springs) the turbo's fully spooled pushing me along. Slight creep occurs - up to 11.5psi at the top of 3rd gear. I see a clear leveling off of the pressure curve on my log, but then it gradually increases to 11.5psi by about 6,300 rpm. Good news is that even with the 440's I'm still in good shape - hitting 90% duty cycle at an 11.0 AFR (still tuning). The IAT went up 30 degrees from ambient on a 2nd & 3rd gear pull. Which seemed like a good bit of heat - but compared to my twins, pretty impressive. They raised (on a 35 degree day, mind you) the IAT by 50 degrees on a similar pull.

The radiator and fan solution is working out supremely! Unfortunately, June has brought with it high temperatures and humidity here in the central lower half of the country. We were tuning the car in low 90's and high humidity. Capacity has to be more than double the old one. The tuner also adjusted my cruise timing, which also no doubt helped to reduce the heat getting put into the engine. But my fans don't even come on anymore unless the car is sitting stationary in the heat with the A/C running. Temps under cruise are in the 165-170 range, which is nice. In hindsight I'm glad I chose to stick with the stock motors and fans with the Aristo shroud. The fans are plenty adequate. Meanwhile I don't have any concern about blowing my stock circuit with the larger amperage motors of the Aristo fans. My tuner hinted at the fact that he would prefer to control the fans via the ECU. If that means at the end of the day new wiring and relay is necessary, I would probably go ahead and put the Aristo fans in just because I have them.

As it sits presently:

The top compliment so far has come from my kids. My 6-year old daughter declared that the car sounds like Sonic. And that it's even FASTER than sonic (when it kicks down and boost hits) sometimes. My 5 year old declared - "All car should sound like this!" We are very much in agreement!

Here's a sample from one of my logging sessions. 2nd and into 3rd.

 

Awesome build! Any idea how much power you're making?

 

Thank you. I'm on stock 440 injectors. I hate to guess but I'd say maybe 330-350 at the wheels. I logged again today and with fuel trim a click richer, I'm pushing north of 95% duty cycle at the top of 3rd gear just short of 12psi. I'm about maxed out. Waiting for a delivery that should alleviate this bottleneck so I can crank up the fun a little more.

 

For a year I've had some 1000cc injector dynamics freshly cleaned and flow tested injectors ready to go in. But I'd not picked up a rail to go with them. I figured no point if wasting them on the stock twins. So now that I have the bigger snail installed, it was time for more fuel. I looked at a few different rails, but kept coming back to the Radium. They seem to be very well made. So I pulled the trigger, ordered me some plug & play pigtails for them and installed. Of note - I'm still on the stock feed and return lines.




Installed and ready to go. You'll noticed I cracked the outer layer of my oil cap removing my coil pack cover a couple weeks prior. That's been remedied. Not pictured also is a flex fuel sensor I installed and connected into the Haltech.

So with these injectors and the 340lph pump, I'm hopeful to reach 500+rwhp on e85.

However, we seemed to hit a number of snags along the way.
One thing my tuner noticed was that the ve map didn't seem to look right. So he had me go validate the quick spool valve. It's supposed to open at 5psi with the stock wastegate spring. But, it starts opening just shy of 5psi but isn't fully locked open until about 11psi. So there's a range there (right where the ~7-8psi wastegate spring) at base boost pressure where we weren't tuning for this QSV to still be transitioning. So he addressed that hole with this newfound knowledge.

Next, my tuner was just not getting the car to get the fuel he was calling on in boost. It seemed a little bit erratic. He felt fuel pressure wasn't where it needed to be. He turned out to be correct. I don't have a fuel pressure sensor, so I rely on the AFR readings to indicate that we have the fuel issue. However, with a properly position go-pro, we confirmed this with the gauge under the hood. So we took a few actions:
1) Did the fuel pump wire modification to ensure the pump is running with full voltage anytime the key is turned "on"
2) Removed the fuel pump assembly to find the Aristo fuel filter was in unbelievably filthy condition. The dirtiest he's ever seen. We swapped the GS300 filter (original) back into the housing. I've ordered another filter, and will install when it arrives
3) Re-wired the fuel pump connections - The connectors I utilized didn't stand up to the 5 fuel pump assembly removals and installations that we did over the past week. The reality is I had a bad connection. I realized this when I went to start the car and the fuel pump was no longer functioning. Went back to the tried and true solder approach.


4. Modified the Aristo hanger - The Aristo hanger uses fuel out of the feed side of the pump to drive the siphon that picks up fuel from the other side of the tank to keep the pickup side full/fresh. So basically, a portion of the fuel that would otherwise be sent up the line to the fuel rail is being expended on this contraption to ensure your fuel is getting transferred for pickup. Granted, that is important if you want to use more than 50% of your 20 gallon capacity. So what we did was, we utilized the vacuum setup from the GS300 and modified it to work on the return side of the equation on the Aristo pump. So now the return fuel pressure / volume will flow through this device, creating the vacuum to pull fuel from the passenger side to the driver's side. That means 100% of the fuel volume and pressure from the pump can be sent toward the fuel rail.

A few images:
AFTER:





AFTER:




I have a new filter still coming, which I will install, along with some e-85 compliant hose instead of what we had available to us at the time. Also, we'll properly weld the regulator/valve shut. For the moment we put some rubber hose inside and crushed it shut to block any flow to/from the regulator.

I'm really surprised I haven't heard more about making this change. It took us from AFR's near 12 at about 15psi to AFRs pegging rich. It was a LOT of fuel we were missing out on due to the design of the Aristo hanger setup. I can't take credit for this, as it was my tuner/fabricator that recommended this change and put it into action.

Now up to 17psi on e85. The car feels fast, but it still hasn't hit the efficiency zone of the turbo yet. With all the trouble we've had over the past couple of weeks trying to iron out fuel gremlins, I'm going to feel lucky if I can get to 20 psi on e85 with this pump. So I'm already weighing options on what I'll do for more fuel.

However, I am liking the turbo and e-85 overall. The spool-up seems quicker than I would have expected. It feels more athletic than the twins in parallel mode did on spool-up, and puts out more top end at wastegate pressure than the twins did at full bore. My tuner also worked on the low load conditions, and on a road trip earlier today, I got over 18mpg at 80mph in 100 degree heat blasting the A/C non-stop at 63% ethanol content.

I feel like we're making progress, but given the past couple of weeks of difficulty, I'm very cautiously optimistic. It's kind of funny, despite being further and further along in the build, it seems the list of "what's next" never dwindles.

 

I picked up a set of wheels a couple of months back. They are after a 370z. I'd seen the 350z anniversary wheels on the GS and thought they fit the car great. I feel the same way about the 370z wheels. In fact I like them a tad better. 8" in the front, 9" in the back. Staggered tires 225 in the front, 245 in the back. The front fit perfectly, IMO. The back however, stick out about 1/4" to 1/2" too far. At my ride height they stick out further than the fender. When dropped down, they're flush, but as they tuck, the contact the inner side of the fender well. It looks like my dreams of a pretty inexpensive set of wheels and tires is dead for now. I think I'm going to sell them, because even if I did shave the rear fenders, I'd never be able to go wider than the 245's, and I think I'd like to get up to a 285 at least out back at some point to help me stay planted.

 

Keep us updated on your fuel system. I did the hanger mod too and my biggest concern is that the jet valve supposedly still doesn't function after changing pump flow. It's a common issue that the car runs out of fuel at 1/4th tank. I haven't got my car up and running good enough to try it out yet, but I plan to roll with a can of fuel with me in case it runs out around 1/4 tank. If this happens, then there is supposed to be a drilling process to increase the inside diameter of the jet valve till it works.

I used a 525lph pump and am still concerned about my fuel, I hope your 340lph is up to the task. I want to do the pump power with "key on" mod too. Still need to look into that. Mostly I just want better startup with the fuel being at full pressure in the rail before cranking.

I'm surprised you left the oem regulator in the hanger. I removed mine and the stock filter to make room for the 525 pump, then just ran an external high flow filter. With the 340lph I'd think you'd be better off removing all restrictions possible. But I know you'd have to make some heavy modifications to change it again.

 

I have an Aristo hanger, and given it differs from the stock GS hanger slightly, it also reads "off" slightly. 1/4 tank on the fuel gauge readout has always been "empty." for me since i swapped years back. And truly it was/empty at that point. However, I will attest that it appears my gauge is reading "correct" (as it did pre-modification) for the most part. I took the car on a road trip this past weekend, and it seemed to be metering the fuel level accurately. However, I'm not quite following what you're concern is regarding pump flow. Your new pump flows more up to the rail and back than the stock pump did. The way this design works, I think more flow would only increase the flow of the siphon/jet valve. Is there some specific reason you're worried about it functioning correctly other than the larger flow of your pump?

I know I'm going to run out of fuel before the turbo is out of air. It's just really a question of when. 12psi seemed early. Around 20 sounds more like it. The modification will run your pump at full voltage when the key is activated. With that said, I don't think I experienced any difference in starting / cranking time - from this modification. The fuel pressurizes at the rail almost instantaneously when the starter engaged before this mod.

OEM regulator was left in the hanger. When I upgraded the stock Aristo pump to a 255 and then a 340, I didn't make changes. This seemed to not be a problem on the stock twins. But the new turbo and larger injectors need more fuel. That's why I made these changes. The regulator now is not in the equation. It's just there to block off the fuel flow that was previously running through it. Additionally, I have ordered a new filter, and will install it soon. I'm hopeful it is less restrictive than the existing old dirty filter in there. You're right I think I'd be better off without it as far as flow goes, but I'd need a filter elsewhere. Makes sense that you would have done away with it for the 525 body. I'm budgeting and planning now for a fuel cell (I think, vs. triple pump hanger) that I'll probably mount in the trunk to feed the higher volume of fuel needed. At that time I'll install another inline filter that is easy to change, given the amount of e-85 I intend to be using.

 

Took a road trip ~ 500 miles round trip with the car this past week to visit family. The car ran flawlessly the entire time. I was able to achieve a measured 18.2mpg on the trip there (haven't filled up since I returned) on e85 (~65% ethanol based on flex sensor) running 81-83mph most of the trip. It stayed very cool with ambient temps in the mid and upper 90s. It's still very quiet and streetable as it was when running the twins, with full A/C and all the creature comforts of 1999 you'd expect.

 

The jet valve is a problem for many that modify their car to a return system. A lot of IS300 guys talk about it. It is common that you have to drill a larger hole into the valve to get it to work right after making changes. I don't know yet if I will have to do this or not. But if you google something like "jet valve mod" you'll have several different discussions come up. Even some youtube videos about it. If it's not a problem for you, nothing to worry about. I hope it's not for me either.

 

Such a clean build.. Well done Kyle..

 

The threads I read about were drilling (or contemplating it) based on the concern of a bottleneck on the return side with upgraded fuel pumping capacity. I validated with the engine off that I am able to reduce fuel pressure (at full voltage) with the regulator down to 23-24 psi. So at current flow rates, I have plenty of headroom in the return side.

i know you have a higher capacity pump than I do, so you can do a similar validation to ensure the jet pump isn't restricting your target fuel pressure at idle.

Doubling capacity would probably put me over pressure if I were running both pumps at idle. However, I intend to stage them to ensure that at idle and under non-boost conditions only 1 pump is active.