Triple Blowthrough Turbo

[madkaw]

No relay for the fuel pump? 

[Dat73z]

@madkaw there is a relay and 30 amp fuse. Ignition on triggers the relay and the fuel pump green wire gets power direct from the battery. 

 

I think I should have an hr or so later tonight to finally start digging into this. Although I may use the time to finish measuring out for my new wheels so the builder can start the build process. 

[Dat73z]

Since this is in the turbo forum, I've been trying to keep this thread turbo specific instead of a full build thread and most of the sidebar projects I post are generally things triggered by or affected by increasing the pwr/trq output of the s30 platform with the turbo. 

 

One thing I have been working on/struggling with is increasing traction as the car would spin at full boost 60mph on 225 rcomps. So I want to go 245s or wider street tires. 

 

Tonight I started back in the quest for for traction. One struggle with my chassis in particular is how the car was assembled. I am also still running a close to factory setup and I know there are 8.8 setups out there now and more that give a lot more clearance but I'm working with the corner I built myself into over this past decade. So far as I can tell, with the way the chassis was welded on the assembly line certain things like the rockers and suspension mounting points are off left to right. I've seen this on over a few dozen s30s over the past few decades, no two cars are exactly the same. Perhaps my car was built on a Friday 😂

 

So what that means is I'm measuring everything from the DS which has 1/8-1/4" less clearance than the PS front/rear. A small detail but something that needs to be considered when pushing things on your setup to the limit. The clearances were actually tighter but as I posted earlier in the build I set the stage for this next phase by dialing in more negative camber and moving the spring perch height up. 

 

 

Edited February 13, 2023 by Dat73z

[Dat73z]

Tonight I wrapped up the evening by assessing where to mount a fluid reservoir for meth injection. 

 

I'm thinking maybe the washer bottle area would work but I'm not sure how much volume I'd need. In front of the rad support is crowded and I'm not sure if I want to go in the fender well or trunk. Ideally I'd do one fillup per tank of fuel so more research is required. 

 

I'm thinking I can weld up an aluminum or stainless tank in that area that could hold at least a gallon. 

[240Z Turbo]

On 2/10/2023 at 8:51 PM, Dat73z said:

@240Z Turbo Basically I an using an oil pressure sensor to trigger a relay to provide 12v direct from the battery to the fuel pump green wire in the harness. The 12v relay harness I made is perfectly fine, but downstream from the connector the 50 year old OE wiring is all melted.

 

I'd recommend 10G from relay to pump if pulling more than 20amps and/or run is over 10ft, but 12G would be fine if you know you're not pulling more than 20amps and/or the run is less than 10ft.  On the GTR I ran ~10ft of 4g from battery to the fuse block (through a 50amp breaker) and then 12G Tefzel from fuse block to two 330lph fuel pumps.  I get my Tefzel wire from here, but for the low gauge wire I like sourcing from the local welding supply.

https://www.corsa-technic.com/

 

[240Z Turbo]

On 2/11/2023 at 12:30 AM, Dat73z said:

@240Z Turbo apologies I missed your Q on timing. The 123 ignition has a MAP sensor. I pull roughly 1 degree of timing per psi of boost and target 20 all in at 1 bar. I can also control vacuum advance off throttle through the MAP.

 

On a turbo car you want to add timing as you approach redline as opposed to pull timing as you approach redline.  I looked at the 123 Ignition and it appears you have two 2D tables, RPM vs TIMING & MAP vs TIMING, which is less ideal vs a single 3D map where TIMING is a function of both RPM and MAP.

 

When you hit the throttle the MAP goes to atmospheric pressure, where you can typically set a static advance number as the car starts to build boost, which on the GTR is about 14deg.  The lower that advance (retarding timing) the more exhaust energy will be created and the faster the turbo spool.  The downside is that if you live in a hilly area then you are more often under slight load and the high EGT's will put your header through the test.  As the motor builds boost you will then start to retard timing and at peak torque is where you will have the highest cylinder pressures so the lowest amount of timing is used.  After you pass peak torque the cylinder pressures are reduced and you can then start to add back timing.  As a rule of thumb you can typically add at least 5deg of timing from peak torque (where it starts to drop) until redline on 93 pump.

 

Here is what the ignition timing curve looks like on the GTR for 93 pump 749hp@wheels.  Disregard the actual numbers because that is a function of the engine and just look at how timing is managed.  7deg at peak torque ramped to 18deg at redline.  You'll notice that it sits around 8deg until 5400RPM because the torque curve remains flat.

 

 

 

Below is the same thing, but for the EVO IX on 93pump 663hp@wheels.  Again, don't focus on the actual numbers, but how the timing is handled.  Timing is 2deg at peak torque ramped up to 11deg at redline.

 

 

 

 

 

[Dat73z]

Hey @240Z Turbo it is apparent you have a lot of experience with this so thanks for posting the info. I was actually afraid to add timing towards redline as I wanted to get the car on the dyno first to baseline and go from there so I limited my timing at 7k to 30/32 degrees. 

 

Lots to process and I'll dig into it over the next few weeks. The car is likely going to be down again for the next month or two as I come up with and execute a strategy to modernize all of the wiring. 

 

I'm still at the point where I'm pushing things and they fail so we rebuild/tune it back better until the next weakest link fails. 

[240Z Turbo]

On 2/13/2023 at 11:52 PM, Dat73z said:

Hey @240Z Turbo it is apparent you have a lot of experience with this so thanks for posting the info. I was actually afraid to add timing towards redline as I wanted to get the car on the dyno first to baseline and go from there so I limited my timing at 7k to 30/32 degrees.

 

I just downloaded the old Wintec2 software so I need to locate my old tune files to see what type of timing I used to run on my 3.1L twinturbo w/125 shot nitrous.  However, I'm thinking it was around 18-20deg peak torque.  30-32 deg seems like a lot of timing for 93 pump even at redline so be careful.  The two tools you need are a wideband, which I believe you have, and a good knock setup that allows you to discern between real knock and engine noise.  I can't stress enough the importance of a good knock sensor setup because your motor will live and die by engine knock on a turbo motor.

 

You've probably seen my old setup from 20 years ago, but it ran 10.6@134 and to my knowledge that motor is still alive and running to this day.

 

[240Z Turbo]

This was from 2001, but should give you a feel for what the motor would take on 93 pump and I think I was making peak torque at ~4200rpm.  Didn't know as much back then so probably could have jacked in more timing at Redline, but I'll see if I can find my last tune file.  Important though is that I used the knock sensor religiously to tune.

 

 

Edited February 16, 2023 by 240Z Turbo

[Dat73z]

@240Z Turbo how much boost were you running on that setup? 

 

Thanks for the tables that's a helpful reference point and yeah I'd like to have some form of knock detection. 

 

To be clear the 30/32 value is all in without boost retard and I pull ~1 deg/lb of boost so it's closer to 20deg all in at 7k @10psi. I'm also running 91 pump and looking at meth injection since fuel availability and costs are issues for me. 

[Dat73z]

A quick update on the build. 

 

I've been pulling 80hr weeks at work and just haven't had the time to touch the car, and also my wife wants to adopt a dog this weekend lol. 

 

But the plan is to start pulling the dash. I think I need to get a moving blanket first or something to lay down on the floor to not ruin the dash as the last time I had to off was a few years and a few houses ago to install a new dash skin. 

[240Z Turbo]

13 hours ago, Dat73z said:

@240Z Turbo how much boost were you running on that setup? 

 

Thanks for the tables that's a helpful reference point and yeah I'd like to have some form of knock detection. 

 

To be clear the 30/32 value is all in without boost retard and I pull ~1 deg/lb of boost so it's closer to 20deg all in at 7k @10psi. I'm also running 91 pump and looking at meth injection since fuel availability and costs are issues for me. 

From memory I could run about 18-19psi on 93pump and on race gas (110L) I would simply add the 125shot on top of that or I would not run the nitrous and up the boost to ~28psi (from memory).  Felt about the same powerwise either way on race gas, but the nitrous made the boost hit instantaneous.  Because I was running a Powerglide trans I pretty much had to hit the nitrous off the line to get it going, but with lower boost (maybe 12psi).  After the shift I would hit the boost controller button and go to high boost.

 

I located what appear to by my pump gas tune from right before the car was sold and I had TimZ open the files yesterday with his software.  However, the timing values seem abnormally high so I don't want to reference them.  I asked TimZ if he could provide some general timing advice to this thread since he probably has the highest HP L6 in the USA.  I've just been out of the L stuff for so long I simply don't remember. 

Edited February 17, 2023 by 240Z Turbo

[Dat73z]

Thanks @240zturbo, and this is why I love HybridZ and continue posting here even in a time when everything has basically moved to FB, IG, etc.. Lots of concrete info on here from people who have actually done this whereas it's hard to separate the opinions from real data on social media. 

[240Z Turbo]

On 2/17/2023 at 11:39 PM, Dat73z said:

Thanks @240zturbo, and this is why I love HybridZ and continue posting here even in a time when everything has basically moved to FB, IG, etc.. Lots of concrete info on here from people who have actually done this whereas it's hard to separate the opinions from real data on social media. 

 

I don't post much build stuff on FacePlant and tend to stick to the forums because it is easier for people to find the information.  It's good that you are documenting your build and hopefully it will inspire others. 

[DuffyMahoney]

Facebook sucks compared to forums.  

 

Did you get a dog!? 

[Dat73z]

@DuffyMahoney Yeah, we're super excited- he was born just a couple weeks ago so we're waiting to pick him up at 6 weeks or so. 

 

Just a quick update on the turbo build, I realized life was getting too crazy so I decided to take a couple week break. My life is way less crazy without project vehicles, that is for sure. My wheel builder texted me for an update on the measurements and I totally unplugged/forgot. Later today I'm planning to pick up a moving blanket from Harbor Freight and start the dash teardown along with figuring out the barrel measurements around my chassis/suspension. 

[Dat73z]

Tonight it finally stopped raining so I grabbed some moving blankets to prepare pulling the interior again. 

 

Out of curiosity I plugged the battery in and keyed the car over. It fired right up on the first crank so I took it for a quick spin around the block. My electronic fuel pressure gauge is out and reading 0-1psi while my mechanical in the engine bay showed 3.5psi so I stayed out of boost to play it safe.

 

I need to gut all of the electrical and go through everything so that will be my spring project. 

[Dat73z]

This AM I finally had a few mins to work on things a bit. 

 

I started off by firring up the car and letting it idle up to temp for a couple of fan cycles to get an idea of where things are at before I start tearing things apart again. 

 

There is definitely a slight carb imbalance which I'll attempt to work out a bit more this go around. My fuel pressure sensor read 3psi for a while then my FP warning light went off again to 0-1psi like I saw yesterday on my short drive while the mechanical gauge read 3.5psi. So I'm assuming this may be electrical related. 

 

Hopefully I get start tearing into the dash later today. 

[Dat73z]

Just a quick update, it's been a busy week but I think I've figured out a few more pieces of the build. 

 

After some more measurement I decided that my existing T3 brakes are just too large for the wheels I want to run. I like the setup but the brakes are absolutely massive. So I stopped by ZCarGarage which is down the street from me and purchased their StopTech street setup with the ebrake. Unfortunately it sounded like it may be a couple months until the kits are back in stock. My wheel builder has worked with Rob and ZCG before so perhaps I can measure a wheel on one of their shop cars, I'll need to call and see. 

 

For the electrical harness I still havent decided what to do about that but I started tearing down the interior so maybe once I unloom the main harness and get a good look at it I can figure out if I want to replace everything or repair it. This would probably be a good time to put in the new headliner I've been putting off since last summer. 

 

In the background I've also been doing some random welding and fab work for some friends like the L series -10 block vent. 

[DuffyMahoney]

You will love the Zcar brake setup.