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[Sept 4, 2015: Front Brake Upgrade (continued)]

Sept 4, 2015: Front Brake Upgrade (continued)

The ST185 calipers line up and bolt directly to the AW11 front spindle. It could be used as-is but the pads overlap the rotor a bit. Grind the caliper bolt holes as needed to get the rotor to contact all of the pads

Done!!

[Sept 4, 2015: Front Brake Upgrade (continued)]

Sept 4, 2015: Front Brake Upgrade (continued)

Here is the second attempt and this time I did a better job

[Sept 4, 2015: Front Brake Upgrade (continued)]

Sept 4, 2015: Front Brake Upgrade (continued)

The keen observer might be wondering about the 5-lug pattern of the Celica rotors. But the thing that makes this job easy is that both the AW11 and the Celica use the same hub dimension. So all you have to do is center the disc using the hub/rotor ID, align one lug hole, and then mark and drill three new holes.

What I did was I found a large socket that would just perfectly fit in the rotor ID. For me it happened to be a 39mm impact SnapOn socket. With both rotors concentric, tighten down a bolt to hold them in place, mark the pattern, and drill away. The 4-bolt piece you see here is a machined out center from my old rear non-vented rotors that I use as a wheel space. But the same would apply if you took a stock rotor and mounted it upside down.

I didn't do so well with the first rotor as one hole broke into one of the Celica's pattern, but in the end it doesn't matter. The hub is what centers the rotor and the force across the surfaces of both faces is what the torque is passing through, NOT the studs.

[Sept 4, 2015: Front Brake Upgrade (continued)]

Sept 4, 2015: Front Brake Upgrade (continued)

All that extra meat comes with a big downside. Ugggg. Rotational mass and unsprung weight. I know, two piece rotors could be just as light as stock such as a Wilwood setup, but again, $$. At any rate they can always be upgraded later.

Oh I forgot, I was also looking at the Lotus Elise/Exige's brake rotor size and they run 288 mm front discs. So not only is my MR2 heavier but it has 11.6% smaller front brakes? Yeah screw that! This front brake upgrade was loooooong overdue!

[paved]

Laguna Seca for you! I'm heading to Maui!!

They don't have any paved tracks on Maui!

Sux



The long summer gave me plenty of time to think about the car. By early Sept. Mike and I had set the date for Laguna Seca to be December 13. I knew I was still busy for a bit longer with weekend work events and wanted to have time to improve the car.

The two biggest issues I had at Thunderhill was:
1. Brakes.
and
2. Front traction.

Brakes. Oh my brakes. At Thunderhill I felt like I had either too much horsepower or too much weight for the brakes. They would stop me well enough, but I was nervous to really squeeze them hard. I kept trying to accelerate for longer a duration before braking at each corner but I found myself timid or not able to trust the brakes.

Nevertheless, I did hammer them a few times and wow those Porterfield pads are NO JOKE. With the tires and brakes warmed up WOW the car can stop. But sure enough it wasn't long until I was getting a ton of modulation from the brake pedal and returning to the pits each time I could feel the brakes had warped. It wasn't until the next day driving to work that I really realized just how bad they were.

So as shown on the previous page I did indeed replace all four rotors. I had to. The car would chatter like crazy every time I slowed down from any speed. But it got me thinking about my brake setup....

Back in 1999 or 2000 when I was 19 or 20 I installed front brake components at the rear. I've always known that as a result I have a greater rear brake balance but it didn't take much pondering to understand just how out of balance they were.

Consider the following.

Stock 1987 front caliper bore diameter: 50.8 mm
Stock 1987 rear caliper bore diameter: 36.5 mm
Front to rear ratio: 1.39:1

Now consider the surface areas:
Front stock caliper: 2026.8 mm^2
Rear stock caliper: 1046.3 mm^2
This is a stock front to rear pressure ratio of 1.94:1

By running front calipers in the rear I've effectively increase my rear brake balance by 48.5% (all things equal; yes I know there is a progressive rate factory proportioning valve). This is crazy. So I started looking into a larger front brake setup.

Doing some research there are a few ways to do this, but I don't have a big budget and prefer to use easy to service/replace OEM components so I went for the ST185 Celica Turbo Alltrac single piston front brakes.

Sept 4, 2015: Front Brake Upgrade

ST185 front calipers are a single 57 mm diameter caliper, which is a surface area increase over stock 87-89 fronts of 25.9%. There is a twin piston ST165 caliper, twin piston providing a better spread of the forces across the pad and better pad wear and performance, but with each piston being 38mm, it's increase over stock is only 11.9%. Calculating the piston surface area ratio of ST165 front to AW11b fronts-installed-to-rear, it is only a 6.2% improvement over front AW11b caliper + front AW11b caliper.

For these reasons I went with the ST185 and WOW am I ever glad I did this. The car has noticeable more front brake dive and stopping power and brake response has definitely increased. Temperature readings of front and rear still show the rear rotors having a slightly higher reading, but at this time it's unknown how much of this is from the larger rear brake bias or warmer ambient air due to close proximity to the engine.

Sorry for rambling, here comes the pics!!

Side by side comparison. ST185 rotor dimension is 278 mm compared to stock AW11b which is 258 mm. This is a diameter increase of 7.8%. Torque or in this case braking force is measured by the force acting on each brake pad by the caliper times the distance from the center of the rotor (radius). And we've got two rotors and four brake pads. So any increase in rotor diameter is a nice compounded benefit!

Various thicknesses. Keep in mind that the AW11b front rotors shown are used and therefore worn from stock. I love the extra thickness, the extra meat. It's gonna take a lot more heat to warp these puppies and I'm reducing the amount of brake force to my rear rotors so it's a big win-win.

Oh well

Go to "Maui Motor Speedway" http://www.racingin.com/track/details.aspx?s=HI&Address_ID=0411

Laguna Seca for you! I'm heading to Maui!!

They don't have any paved tracks on Maui!

[LAGUNA SECA DEC 13, 2015!!!!!!!]

Went on a lot of wheeling trips for work and did a ton of marketing.

During this time however I knew I could not go on much longer without getting back on a race track.

So Mike and I talked about it and decided to schedule our next track event for LAGUNA SECA DEC 13, 2015!!!!!!!

Ohhh man this thread is about to get REAL SERIOUS REAL QUICK LET ME TELL YOU!!!

And some of this

And some of this:

Between May and Sept I didn't have time to do much of anything with the MR2. It even was parked for a few weeks at a time during the summer while I was out doing this:

[May 18, 2015: Datalogging AFR]

May 18, 2015: Datalogging AFR

Finally got my AFR gauge connected to my Propeller Microcontroller. It was so easy as the Innovate MTX-L has a simple 5vdc digital output. Just connected one wire and I was done

Now I am data logging AFR and manifold pressure.

And.... um well I quickly found out that I am in the 13.x:1 AFR range under full boost Ohhh man it's not good. So I'll need to sort this out, and like always, more to come on this

[April 22 & 24, 2015 (continued)]

April 22 & 24, 2015 (continued)

And here it is all back together.

In the meantime I also encountered an issue with the el cheapo water injector I installed JUST BARELY ONE MONTH AGO!!

This pile of crap injector was leaking and I nearly tossed a rod because of it. Water had leaked into the S/C and I went to start it up one day and it fired up and then idled really rough and then just HALTED instantly. WOW it sounded horrible. I cranked it once and it DIDN'T LIKE IT. Stopped the started in it's tracks. Ended up having to pull all plugs and disable the OCR (turn off fuel pump) to crank and spit out all the water from the intake and cylinders. It took a looooong time of just cranking and cranking afterwards until it would start. I think the intercooler was full of water....

Anyway, SCREW you Chinese injector. I went ahead of bought this bad mama jama that I should have done in the first place: "Mini Lightweight 300 PSI Solenoid" http://www.alcoholinjectionsystems.com/product_info.php?cPath=35&products_id=499. I was actually so upset that I posted the following review on Amazon:

Source: http://www.amazon.com/gp/customer-reviews/R2QKMQXGLN2FBW/ref=cm_cr_pr_rvw_ttl?ie=UTF8&ASIN=B00LGIZKMI

I purchased this solenoid Dec 29th, 2014, and installed it March 10, 2015. I'm using this on a DIY 50/50 water methanol injection system on my Supercharged MR2. I'm using a 60 PSI Shurflo pump with filter and a Shurflo Accumulator to maintain a constant pressure at the solenoid. After only 2 weeks of use the solenoid leaks, something I found out that almost destroyed my engine. I had to remove my spark plugs and crank the engine to clear the water out of the cylinders. When the front side of the solenoid is pressurized it has a small but steady stream of water just dripping out non-stop. I'd like to return this Chinese pile of crap but I purchased it more than 3 months ago so I'm SOL. It claims to be "Heavy Duty" but you can just tell it was cheaply manufactured down to the Chinese crappy wires that came with those Chinese crappy twisty ties (if you've bought made in China parts then you know what I'm talking about). I am going to do what I should have done and that is to get a high performance solenoid from Alcohol Injection Systems (search for "Mini Lightweight 300 PSI Solenoid" on Google). It's $70 but I don't want to take any more chances in damaging my engine. I do not recommend this solenoid for water injection.

So out it goes and in goes the AWESOME Alcohol Injection Systems 300 PSI injector. Far smaller, far lighter, less amperage requirement, MUCH BETTER!!

edit: I forgot to include the first image

[April 22 & 24, 2015 (continued)]

April 22 & 24, 2015 (continued)

The old seal was R-O-C-K H-A-R-D! Wow it needed to be replaced a long time ago. I am fortunate that it was bad, otherwise I might have blown a crank seal like a rear main and man that would have sucked to replace.

Pic 1: Note the grove in the shaft the hardened seal had cut.

Pic 2: There is no snap ring or index on where the bearing should be pressed on, so I found a drill bit that would correctly fit between the bearing and distributor gear (happened to be a 1/4") so I could get it back together the same.

Pic 3: Outgoing KOYO (thank you so much bearing!) and incoming AMCAN......?

Pic 4: Used our lathe to get the grove roughened up with some sand paper. I didn't want to take too much off but did need a rough surface to break in the new seal

Pic 5: Pressing the new bearing on using the same drill bit as reference

Pic 6: I installed the new seal at a height slightly deeper than before so as to not contact the deep grove on the shaft

Pic 7: Reassembled!

Pic 8: New cotter pin hammered in and ready to go!!

[April 22 & 24, 2015 (continued)]

April 22 & 24, 2015 (continued)

Oil was just pouring out of the poor distributor and it had gotten all over my poor alternator. Sheeeesh.

Locked it up in the vice

Drilled out the pin (was tricky, started with a small drill and tried my best to keep it straight)

Punched out the remains of the pin

Marked the alignment so I don't screw up the timing

And apart it all came