motorheaddown

Sup ClubLex?!

It's been a while since I've been on the forum, and I wanted to post an update to a project that's gotten a little out of control (but that's actually good).

In '02, I purchased a '95 sc300 5-speed with 43k miles from a retired couple in Maryland. I was going to work with PHR on a project, but that fell through (long, unpleasant story). The good news for me was that it was an opportunity to really learn something about piecing together a turbo conversion myself. If you're considering embarking on an NA-T yourself, be prepared for delays, cost overruns, and multiple approaches to solving problems along the way. I now understand why tuners often run into the same issues on project cars. DIY turbo conversions are *not* for the mechanically challenged.

I initially was just going to convert the power plant, but I was encouraged to do it right the first time by local turners and individuals on the forum. Here's the current list of mods on the car:

Toyomoto manifold/dp/wg pipes/midpipe/oil-feed lines/6-speed DS mod
Sound Performance sp63 turbo A/R .71, 4" compressor inlet
Turbonetics Racegate
Siemans 720cc/min injectors
2mm hg
3-angle valve job on the head
PLX Devices M-200 W/B
AEM ems/egt sensor
Custom fuel system (dual walbros feeding an in-tank Y block to a 8AN bulkhead fitting; 8AN line leads to Y block in the engine bay that splits to dual 6AN lines feeding a dual-feed, center return GE fuel rail; second pump comes on a 1-bar of boost)
Aeromotive FPR
GM 3-bar MAP/AIT sensors/boost control solenoid
LS1 coils running wasted spark (distributor is used for crank/cam position *only*)
FMax IC pipes
JDM FMIC (900+ cfm)
TT 6-speed tranny/clutch disk/LSD/sway bars
RaceLogic traction control
Dereks Devices meth injection kit
Kevin *****'s digital dash (no guages!)
RPS Max pressure plate

The car is currently running NA. Unfortunately, I hacked up one of the FMax IC pipes, and I'm waiting on a replacement. However, all the difficult work is complete. I have the AEM running on 720s, and the fuel system and ignition system have been completely replaced. I now run the custom fuel system listed above and LS1 coils to fire the plugs. So far, everything's working great.

The fuel system was designed to prevent unnecessary heating of the fuel due to dual pumps running all the time. Therefore, I put a Y-block and dual Walbros in the tank. One pump is on all the time. The second pump comes on a 1-bar of boost. The fuel system took 3 iterations to get correct, and the key was modifying the GE fuel rail to be dual-feed center return. I was able to install a 45 degree 1/4" npt to 6AN fitting between injectors 3 and 4. It isn't easy, but it's doable.

To get *around* the problem of the distributor getting in the way of the compressor inlet (pardon the pun), I planned on either using the TT ignition system or something else. Fortunately, "something else" came along in the form of DereksDevises LS1 coils for the TT. Unfortunately, the AEM *only* runs wasted spark for the Supra, but the TT igniter was designed for direct-fire. Consequently, the igniter couldn't handle the short dwell time of wasted spark. Derek Obanion (a.k.a AnArKey) devised a coil-on-plug solution for the TT that *completely* eliminates the TT ignition system solving the problem with wasted spark driving the TT ignition system.

Based on my research of the TT motor and electronics, I determined that it would be possible to use Derek's LS1 coil solution on the NA motor. However, I'd still need the distributor for crank/cam position. Keeping the distributor *just* for the position sensors would provide plenty of clearance for *any* size compressor housing. Unfortunately, I had to completely wire up the ignition system from scratch (as well as the injectors which is another long story). After trouble-shooting some self-induced ignition problems, I successfully got the NA motor running on the AEM and LS1 coils. WooHoo! Now the only thing preventing me from running *any* sized turbo is oil cooling of the pistons.

While I'm on the topic of oil cooled pistons, I needed a way to keep the cylinder temps down under high boost. One way to combat the problem is to install TT piston oil squiters in the NA block. While it's possible, it's not very practicle. Even if I installed piston cooling, it would still be necessary to run race gas under high boost (> 22lbs). Once again, Derek comes to the rescue with an inexpensive solution. I'm going to install a methanol/water injection kit to chill the compressed air flow exiting the IC. Meth/H2O injection will drop the intake air charge to the intake plenum at or below ambient. Using meth injection, I'll be able to run high boost on pump gas, and a meth/H2O mix is very inexpensive to make.

Plans for the driveline have also changed. My initial choice of a RPS pressure plate and stock TT disk is o.k., but I need something with a little more clamping friction. I'm going to try out the SBC kevlar disk and pp. The flywheel side of the disk is OEM, the pp side is kevlar. The pressure plate surface is also kevlar. I'll let you know how it works out. I'm trying to stay away from a multi-disk clutch just for cost and drivability reasons.

About headgaskets, I did take the time to measure the change in head clearance before and after installing the thicker hg. The stock clearance is about 0.056". After installing the hg (which was actually 2.7mm umcompressed), the final squish clearance is about 0.146". The resulting increase in clearance volume changed the compression ratio from 10:1 to 8.4:1. Perfect for a turbo-charged motor. Next time, however, I probably would just go with a TT hg especially in combination with meth injection. In fact, it should be possible to run stock compression at high boost with chilled intake air using Derek's injection system.

The other thing I want to mention is the AEM. In two short words... IT ROCKS! I would never suggest to anyone that they go with piggy-back solutions to engine control. In the end, the AEM will do more for less money. The only thing is doesn't have is good traction control. That's why I picked up the RaceLogic system. The base maps that AEM provides are *very* good starting points. And if you RTFM, I'm convinced that it's possible for a non-tuner to dial in a car. However, the AEM is *very* complex. Don't expect to PnP as they advertise. It ain't gonna happen! You must do your homework to effectively use this device.

As a bonus to using the AEM, you can save a ton of money on analog guages. Kevin ***** has designed a digital dash that emulates a pc connection to the AEM. It *completely* eliminates the need for analog guages that could cost well over $700. The dash is an LCD display, controller, and button interface that let's you pick what you want to display. Additionally, you can put warning indications for over/under conditions. It also has a "peak" feature, and he even has allocations for hp and torque calculations.

Oh... one short thought about FMax IC pipes. For the cost and quality, they're actually *very* good. In fact, they're about half the price of custom front mount IC pipes. Unfortunately, I had some self-induced installation problems that are preventing me from boosting the car. Additionally, with a slight mod to the compressor outlet IC pipe, I was able to install all the pipes through the fenders. You'll have to move two power steering lines and bend some AC lines out of the way. However, I have all the pipes (except the one I'm missing) installed with all the under carrage plastic installed.

Well... that's about it for now. Sorry for the long post, but a lot has happened to the car over the last couple of months. Once I get a replacement IC pipe from FMax, I'll be boosting. I also have to replace some of the driveline components (DS, clutch, pp, LSD). I also haven't tried out the RaceLogic system, but once it's installed (I still have some wiring to do), I'll post my findings as to its traction control capabilities.

-scott

Richie

It sounds like a pretty big project to do all on your own.
I'm looking foreward to your updates, I always like these sort of modifications.
for all the hard work!!

William N.

iTrader: (2)

Scott's back! Hope to see your car boosting soon! Congrats again.

William

Lex Luthor

Good to see that NA-T coming together, let's see some pics...

motorheaddown

For now, there's not a whole lot to see until I install the turbo. The only thing that gives away the mods are steel braided fuel lines and no distributor cap. The IC is not installed, but the pipes are.

I'll take some pics when it's boosted.

-scott

boredguy77

don`t listen to this guy, he is a liar!! he actually drives a civic with a yard blower, and claims he is boosting SO how did you get back on the forums scott?

Angel

Wow, that setup looks really familiar!

Great to see you on here! and nothing but good news it seems. I am glad everything is working out so far.

I did want to say one thing, and I hope all the NA Supra guys are reading this ... "I TOLD YOU SO" (about the 2.0mm headgasket being PLENTY to lower compression for turbo applications). God, it got me into so many arguments, I tried to tell them all that it was fine, no one wanted to believe me

Keep us updated, you know we all want to see numbers Congrats again!

*edit* and I STILL have an extra HKS 1.6mm headgasket laying here, someone PLEASE buy it, even motorheaddown will agree it is PLENTY thick enough for a turbo project

wmulli

Wow, great writeup!

Sounds like an awesome amount of work! I'm really glad it's working out so well for you. Keep the writeups coming

motorheaddown

Thanks for all the kind words. Boredguy77, however, is jealous because I was able to put a car together without using JB Weld to do so! (Just kidding Alex) And William?... Next time you need help on the car, just let me know ahead of time if what I'm fabricating is going to get sold off. (Sometimes e-mail doesn't carry the intended meaning... I know those guys, and they're good friends)

Anyway, I wanted to mention a few other things. It's worth the time and effort to learn about emission controls. In the 2jz case, I would suggest blocking off the EGR passage from #6 cylinder to the EGR cooler especially if you're going to pull the head. It's *very* easy to put a steel expansion plug or NPT plug in the passage. #6 is notorious for leaning out due to the additional heat from the EGR cooler. Additionally, you should remove the EGR delivery pipe that's located in the "Y" intake pipe that's between the throttle body and intake plenum. After trying to remove that thing from the expansion plug hole, I ended up just pounding it out from the throttle body side. I left the charcoal canister in tact. I didn't see any reason to disable it. Finally, I also removed the ACIS butterfly located in the intake plenum. In its place, I installed the AIT sensor. Unfortunately, I do see a rise in inlet temperatures after the car heats up. This is probably what is referred to as "heat soak".

Here's another installation hint when replacing the OEM injectors with peak-and-hold style injectors. As discussed in Angel's project thread, it's necessary to install a solenoid resistor. I *highly* suggest that when you do so, install a 30-amp relay coming directly off the battery to power the solenoid resistor, and use one of the 12v switched wires from an OEM injector to switch on the relay. Additionally, be sure to back track all the unused 12v switched injector sources as spare 12v sources. You can *never* have enough 12v switched sources in the car. Those 12v sources are fused and can carry a good amount of current. I'm currently using the left-over injector 12v sources for the LS1 coil relay, the boost control solenoid, the W/B relay, and my digital dash just to name a few. Trust me... those 12v sources are *very* handy.

Speaking of relays, I *highly* suggest the use of relay sockets when installing additional relays. If you get the right kind, it's almost *impossible* to wire them incorrectly. Additionally, it makes for a very clean install; some sockets even have a rail that allows multiple sockets to be connected together as a "bank".

About W/Bs, I only tried one device, and I've been very pleased with it. I'm currently using the PLX Devices M-200. It's easy to install, has a great display, and is easy to setup in the AEM. There's a simple calibration procedure to setup the multiplier and offset in the Configure->Units menu. I currently have the AEM tracking the W/B output *exactly* which means that I can hide the unit under the dash and use my digital dash or pc to monitor AFRs.

Oh... another thing I want to clear up. I've come across a myth about ARP head studs. I was told that it was necessary to pull the motor to install ARP studs in the block due to limited access to #6 cylinder. That's not true. ARP head studs for the 2jz motor come with a small allen head socket on the tip that allows installation with the head on the motor without removing the engine.

I'm pretty sure the next topic has been beaten to death, but I do want to give it notice here. Drilling/tapping the block for the oil return is *very* simple. I helped Alex and William on their cars, and we got it down to about 45mins of work. there's no need to drop the oil pan (in fact, you don't even have to drain the oil). Just be meticulous about incrementally cleaning out the hole when drilling/tapping.

I do want to make a few honorable mentions. As much grief as Lance (Toyomoto) gets on this forum, I've found him to be a consumate professional. He's taken responsibility for any of his mistakes that occured in my order, and he's been quick to respond with parts and e-mail. I'll admit it was difficult to get his attention at first, but once he realizes you're a serious turbo customer, he's right there to support you. I'd also like to thank Dave Henry and Scott Hureau. They've been *very* helpful and great sounding boards for ideas. There have also been numerous individuals on the CL forum that have answered many of my questions. Thanks!

*EDIT*--- I should also mention Jotech MotorSports of Garland, Texas. Kenny's group has been very helpful. Tony, the crew chief on their race car, is the best in the biz when it comes to fabricating and tuning. Andrew was also very helpful listening to my goofy ideas and answering questions.

Hmm... that's all I can think of for now. I'm sure some other stuff will surface from the cognitive blur that has become this project.

-scott

William N.

iTrader: (2)

Scott....my bad, but after I saw your setup, I had to step it up to try to keep up with you Maybe you want to make me another one j/k!

But you definitely need to give me a ride once its finished...And if you ever need anything, you have my number...hope to hear from you soon.

William

motorheaddown

O.k. Sorry to resurrect my old project thread, but I have some news that was quite a relief.

Over the last month, I had been experiencing major misfire and did a compression test which looked pretty bad. Well, it turns out both problems were self-induced. The ignition wasn't working because I'm stupid, and the compression test was bogus which means I'm double stupid.

I left parts of the coil interconnects exposed which I'm sure was causing arcing to the head. I also goofed up the compression test by not keeping the throttle plate wide open. I reran the compression test, and all cylinders are right around 152psi. Not great, but good enough. The slightly low numbers are probably due to a lower C/R.

I made pulls with the timing severly pulled, and the car ran solid to 21psi (I only did that once). The top end power was pretty bad because of the retarded timing, but there was no knock in my logs. It looks like the LS1 coils will be able to handle the load.

With those issues behind me, I still have a ton of work to do in addition to tuning:
1) TT 6-speed LSD and Toyomoto 2-piece DS
2) ACT HDX pp and SouthBend clutch full kevlar disk
3) Sound Performance tubular manifold and dp
4) Meth/water injection
5) Catless midpipe

Everything but the new manifold is ready to go. Larry will have it to me in about 3 weeks.

-scott

motorheaddown

Here's a screen grab of my latest log.

The AFR in fourth gear is a little high, but that's because I hadn't run that much boost before. It's just a matter of adding some fuel to that part of the map. Also notice how the inlet air temps go down. That's a good intercooler. Timing is about 4-5 degrees. There's plenty of room for some major horsepower. I'll now spend the time to add meth injection. Then I can safely run pump gas at that much boost.

motorheaddown

FWIW, here's a tuned pull at 15psi. Notice that the AFR and timing are much better.

Lex Luthor

That's great news about the motor, hope the rest comes together smoothly for you. I like seeing those logs...
- Jon

5speed300

1 question about the AEM. What stock functions do you lose when installing it? ac, radio, etc.....