Probe Sho 3.2 Turbo Build

[firebat45]

Alright, since MufFinZs and I am working on this build together and he can't properly post, I'll be posting the build thread for this even though it's his car.


The Probe started it's life as a 1990 3.0 Vulcan LX. According to the VIN it was originally an automatic, but who knows. I bought it from firebat45, also on here, and we mostly work on it together.

Plans are 6 speed swap, Turbo, Standalone ECU, and a general updating of the motor. This means switching to Coil-on-plugs, a better cam/crank sensor setup, and other tweaks to improve the motor and update hard-to-get parts.

When I got the car it had been sitting for 4+ years after a dead crank sensor. The way that the swap had been done, there was no room to remove the pulleys without pulling the motor.

We pulled the motor, fixed the crank sensor, replaced a cracked oil pan, and installed a new stock clutch/Fidanza flywheel combo.

I drove the car like this for a while, with minor issues mostly related to wiring.

 

[firebat45]

Next, a lot of work was done on the wiring to try and fix some lingering issues with the car. Bad connections meant some sensors would drop out and make it run/start rough.

Eventually the decision was made to scrap the original ECU and go standalone. This was always the plan, the stock setup (even with a Tweecer/other) is terrible and leaves no room for expanding or changing things. There is a ton of work involved with getting the tune just right, and I'm still working on details of it today. Currently the car is running on a Megasquirt 3 with the MS3X expansion, fully sequential with Toyota coil-on-plugs. The Toyota COPs were chosen because we have used them in the past with success and they have an onboard ignitor, which means they are very easy to drive with the MS3's logic outputs.

At first we wanted to do a direct pin-compatible replacement with the X2J so that in the future we could offer ECUs/tunes to interested people. But working with the DIS turned out to be a big hassle and we decided to eliminate the DIS altogether (another old obsolete part no longer needed). It's much easier to monitor timing when the Megasquirt controls it directly.

To prepare for the turbo, the car needs a fuel system upgrade. We went with dual fuel pumps, Walbro 450lph. This might seem like overkill, and it is, but undersizing fuel pumps is never a good idea.

We are not using an aftermarket regulator to control the flow. Instead, we are taking advantage of the Megasquirt and using a Solid State Relay to control the pumps with PWM. We installed a pressure sensor in the new fuel filter housing to monitor pressure and eventually control the pumps through closed-loop feedback, for now the PWM duty cycle just rises with RPM and boost.

Giant filter, to protect the ID1050x injectors:

Older shot of the filter housing before the transducer and SSR were installed:

SSRs, rated for 40A each. Planning on using them to control the rad fans as well (CCRM delete):

Injector Dynamics ID1050x injectors. These beauties are rated for 100lb/hr and are fine with E85/high boost pressures. No fuel rail boring, these fit perfectly.

 

[firebat45]

The next thing on the list was paint. We had never painted a car before and wanted to give it a shot, and anything was better than oxidized/flaky 1990 Ford Red. We built a temporary paint booth and gave the car a two-tone Tremclad(Rustoleum) paintjob. It's not perfect but it's not bad either. Learned a lot and the next time will be better. Also did some custom badges to personalize the car a bit.

For tuning the engine, we are currently using Megasquirt. Here's an example of the interface, setting up the secondaries.

 

[firebat45]

So while the car had been a decently good daily driver, it was nearing 500000kms on the engine. Time for refresh and a motor built for boost.

3.0L bored out to 3.2L

Wiseco forged pistons, stock rods (used)

New rings

Cracked oil pan. We could have gone with a good one, but it was a good challenge to fix this old one up.

All fixed up.

Then powdercoated

Cleaning up and powdercoating intake bits

New couplers

Aww yiss

All assembled. Sorry for the jump, seem to be missing some pics from the middle.

 

[firebat45]

Then, the beginning of the transmission adapter. We chose the Nissan Sentra Spec V 6 speed manual tranny. There are other trannies that would also work, but this one seemed to have a good combination of easily found, strong, modern, cheap, and comes with a helical torsen (Quaife) differential.

So after drawing up the adapter, we cut a test piece out of 1/2" MDF. Tracing the engine outlines so we can get a nice fit.

After a LOT of back and forth, recutting, testing, etc, we ended up with a nice design all worked out.

Before sending this off to the waterjet shop, we wanted to do one last final check. We drilled one out of a scrap piece of 3/8" aluminum. It wasn't quite big enough, but it was enough to test all the critical holes. The final plate would be 1/2" plate.

Everything bolted up great!

Now, it was time to fit the drivetrain into the car. We will switch to the ATX accessory drive to gain a bit of space, the tranny is about 1" wider than the original, plus the plate itself. Spent a bunch of time massaging clearances and shifting the motor around to get it just right.

 

[firebat45]

The engine bay was still the original red, and had lots of redundant Probe wiring/plumbing along with the SHO stuff. This is all going to get redone, and the engine bay painted.

Starting off:



After stripping out everything and painting:

New control arms and studs, powdercoated knuckles and hubs:

Installing the new motor:

The new transmission mount (bushing stolen from an SHO subframe)

 

[firebat45]

This weekend we finished the adapter plate for the Sentra transmission. The waterjet company did a great job cutting it out but all the holes needed to be properly drilled, reamed, tapped, and countersunk. Fits really nicely.

To fit around the adapter plate at the back of the rear head, the coolant outlet needed to be modified. The elbow that leads to the heater core needed to be cut off and welded up. This isn't a big deal, we can just run the heater core off the other side of the coolant outlet instead.

Another thing we noticed doing highway pulls for tuning was the horribly inadequate brakes. 2-3 medium-hard stops from highway speed had the brakes hot and barely working. Definitely in need of an upgrade.

We wanted to stick with 16" steel rims for the winter tires, so anything we picked had to fit inside that. 2010 Crown Vic front rotors (12.015") fit nicely along with some Wilwood calipers that have been on a shelf in the shop for way too long. Big upgrade from the original 10.3" rotors.

Rears will come at a later date, and nice new hardware has been ordered for the brackets (and the tranny adapter plate). Bracket and caliper will get powdercoated of course, after the fabrication is all done. Stainless braided line and AN fittings on the way as well.

 

[Devin]

So by ditching the ECM, what did that gain you ?

The rear seal cover is purdy!

 

[firebat45]

So by ditching the ECM, what did that gain you ?

The rear seal cover is purdy!

I'll get more into it as I work through the pictures/build, but it gives us full control over the motor/turbo. There is way more data available for logging at a higher speed than the stock ECU. It also lets us work with any sensor we want, so we can delete all the hard to get and obsolete parts like the CPS, DIS, Narrowband O2s, etc.

Basically, instead of a closed-down, early 90s engine computer, this is a fully configurable, modern, high speed engine computer.

 

[Devin]

Nice. I hate our PCM, so I will look forward to these developments!

 

[SHOVNST]

Very nice work!!!


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[luigisho]

This is such a complicated and great project. Great stuff.

 

[zoomlater]

is no CPS the cam position sensor or crank position sensor
Very nice work, look forward to seeing this done

 

[firebat45]

is no CPS the cam position sensor or crank position sensor
Very nice work, look forward to seeing this done

The plan is to eliminate the crank sensor altogether and either mod the cam sensor or design a new one to do all the engine position sensing. No more hard to change, expensive crank sensors that get wrecked by water pumps.

Plenty of new cars run a cam sensor only. It is able to provide all the data an ECU needs. It's actually better than a crank sensor, which can only tell you the rotation of the motor and not what stage of the cycle it's in (compression vs exhaust, intake vs power).

 

[blk\blk90]

Is this the car getting the 6spd Sentra trans?

 

[firebat45]

Is this the car getting the 6spd Sentra trans?

Yep. Updated posts above with more info. It's a good choice for tranny. Not too hard to find, comes with a Torsen (Quaife) LSD, stronger than the MTX-IV, etc.

There are Sentra guys running 600+ HP. The tranny isn't known for exploding either. It might not hold up to the power we are looking for, but it's definitely built a lot beefier than the MTX-IV. The input shaft and main shaft are way thicker, and the tranny has much more reinforcement in the casing.

We are planning on figuring out this swap for a SHO as well. The plate will be the same, but the axles, shifter, clutch, and tranny mount will all be different than the Probe. Then we'll be able to offer the parts to other people interested in the swap. Not fishing for interest right now, there's a ways to go before we're ready for that. We'll make sure to go through the proper channels at that point, too.

 

[firebat45]

So right now the plan is to skip power steering after the rebuild, but the backup is electro-hydraulic. We've installed a system similar to this in the past on a different car and it's great. You just run an electric pump that replaces the power steering pump, and set it up on a relay to only run when the car is running. It does take a good amount of power.

Last time we did it, we ordered an expensive pump from the UK, some Vauxhall/Peugeot unit. Shipping was a killer and it's hard to find UK salvage yards that will ship to Canada. This time around, there are more North American options. We got this pump from a Mazda 3. It's nicer than the older one we had because it has a remote resevoir, makes placing it in the car easier.

It runs off CAN-BUS for control, which is a bit of a pain. Hopefully we can find some information on the protocol and be able to tie it in with the Megasquirt, but in the meantime it's easier to just control the motor directly ourselves. It's a 3 phase electric motor, which can be controlled with a hobby style electronic speed control.

Might seem strange to use an RC car part to drive a motor like this, but this controller is massively overbuilt. It's rated for 150 Amps, the original fuse for the Mazda 3 pump was only 80 Amps, and in typical use it pulls 10-40 Amps.

 

[DJSHO91]

Awesome build! Looking forward to further build updates. SHOTASTIC!

 

[SHOVNST]

Very nice work! Looking forward to the completion.


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[Toolman]

Loving this!!