Harlan's Impossible turbo build.
 

UPDATED 3/16/15
Still going strong at 4psi.
Here's the rundown of my build:
09+ tranny INSTALLED
Agency Power Exhaust and midpipe. INSTALLED
Ebay T35 turbo.
Ebay 38mm wastegate.
PTP turbo manifold.
GM IAT
55lb ev12 injector for preturbo water injection.
Arduino serving double duty as boost controller and WI controller.
IGN-1A coils.



OLD:

I plan on getting the turbo on the car first and setting a mild tune with 4psi then getting all

the software and hardware to play nice.

Yeah, that all sounds completely reasonable. Figuring out the software as I wait for parts to

arrive. Will be doing most of the install in about a month. This is a conglomeration of a lot of things I've tried successfully and otherwise, I'm not expecting everything to work out of the box, but it's the journey that's important to me.

Any encouragement or helpful criticism is great, but please don't turn this into a "It will never work." thread unless you can provide facts to back it up.


NEW:

Well a lot of my plan has changed/been adapted. Skip a few pages in unless you just want to watch me make mistakes. :)

The Mk1.

Mk2

Where did you get the 3.92 diff ratio? (not a 3.90?)

Do you have the correct transmission speedometer gear to match the 3.92 diff?

PS: Theoretical top end speed for a 3.92 diff is awesome.

I believe it's off a miata. Got a good deal on it and it should lower my cruising rpms and give the lower gears longer legs. Top speed should be great.

i see "ebay" , "no intercooler" , "glasspack exhaust"


clicking back button..

Should be fun to watch ;)

Everyone loves a good train wreck :)

Thanks for the support! :) I did not wake up one morning and decide to do a turbo build, but have been researching and planning for almost a year. It might be a colossal failure or it might take months and a lot of money to get right. Either way, sit back and enjoy the show.

for a year and you didn't read how not to use ebay special boost items?

What are you doing for a manifold and why no intercooler? Water injection or meth injection? And why mess with the Arduino when boost controllers and W/M controllers are so cheap?

Grand ideas, eBay parts

Seems a bit silly, but good luck just the same

It's going to be a rear mount turbo where the muffler is now, using fuel injectors for pre turbo water injection. Water is the plan, but may go to water/ethanol or water/methanol. I have a water/methanol controller and I hate it. They did everything right except the application, but I can bitch about certain WI companies later. Fuel injectors let me have complete control over volume, and they have been reliable for now. Manual boost controllers are cheap, digital aren't that bad either, but I like more control and it's darn easy to do with a microcontroler also I should be able to have boost/WI/knock detection on the same screen.

I'm not trying to make a dyno queen or a track star, I'm just trying to make something fun for me. I figure 300hp max with power coming on much lower and staying all the way up.

Also if you were going to inject massive amounts of water pre turbo, would you use a turbo that costs more than $200?

Ah, a rear mount. That presents some additional complications.

If I was going to put a turbo on my lawnmower I would still pay more than $200

And it's more the wastegate that I would be concerned about

Rear mount does have some major advantages: 1) no complicated exhaust plumbing 2) no excess heat under the hood 3) no intercooler blocking airflow to the radiator 4) plenty of room in the space vacated by the stock muffler. A major disadvantage is having to run oil to the back or come up with an independent oiling system with an electrically driven pump.

Glasspacking probably won't last long, steelpacking might be better. An oval sectioned air pipe forward would preserve some ground clearance. I'd be surprised if injecting water upstream of the turbo didn't cause damage to it, but for $200 it's a relatively cheap experiment.

Get an oil-less Comp Turbo

Lag will be a major issue. Rear mount results in a serious volume of exhaust piping to pressurize before the resulting response. You also have the same on the intake side plumbing all the way back to the front. Double lag whammy.

Running a 2" charge pipe so I'm not worried too much on clearance. The pipe itself will give some charge cooling, and the pressure drop over it's length should also cool the charge some while driving the turbo closer to its efficiency peak at high flow. I'm returning the oil with a fuel pump, I'll change over to a normal scavenge pump if it breaks within 6 months. The glasspack blanks I'm getting should be pretty easy to gut and reline with stainless steel wool, which will be my first step with them.

Gotta get back to torturing transistors for science.

harlan--you may want to speak with these people about how to properly set up a water injection system:
http://www.google.com/url?sa=t&rct=j...gujrVoU92IXE8w
These are good people who know how to really set up a great system and they have the parts/experience to get it done.
You will need a pretty big tank.

One thing you may not have considered-- that 3:92 diff ratio could cause a little difficulty in start off's.
Obviously you are going for a cruiser-- in town you may spend more time than you want in 4th gear?
--you may end up shifting a lot?
The glass packs will not last long at all--even with the exhaust cooling you will obviously have in place. The fiberglass will burn out after a little.
Spend a little more money and get one with SS packing--you will be glad you did.
This will be a very interesting build.
I am really interested in how you mount the nozzles and coordinate the injection with the intake valves. Or, are you only going to put nozzles on the primary runners? If so the intake valve transitions on a properly designed system will be difficult to tune for?
Knock sensor developments will also be very interesting to follow.

Great site OD with lots of great info. Unfortunately I found their site early while searching water injection and that made me throw out the idea of using fuel injectors despite the obvious advantages. After a bit more research and actual testing I've found that newer fuel injectors are designed to run higher ethanol fuels (read extra water) and are made of stainless. The only potential problem is the spring which is regular spring steel. The injectors I have on my desk now are stock rx8 red injectors and have had water running through them several times and were left filled and soaking in water for a week with no ill effects. If these fail I'm gonna go searching for a pair that is rebuild able and then go find a stainless spring.

Start offs may be more difficult, but it's only a 13% change. Also I don't really care about getting off the line. I only plan to be at 2k once after stopping.
May end up upshifting a lot, but the way I figure I already have to shift too much in town, this should give me longer legs on each gear and only hurt 1st.
Repacking the glasspacks with stainless, doing it myself because off the shelf are EXPENSIVE.
A magician can't give away all his secrets, but I do have a trick up my sleeve for injecting in the runners.

Suggest you PM Bumblebee and have a good talk to him . He has made a really good rear mount setup and he may well be able to help you get it right 1st time .

https://www.rx8club.com/series-i-major-horsepower-upgrades-93/rear-mount-turbo-project-204248/


Here is a thread and good luck man . Looking forward to this thread

Thanks guys. I have both Bumblebees and Rotorocks threads bookmarked. Unfortunately my build is closer to Rotorocks build and he hasn't been on in a year. I know I'm the black sheep on this, which is why it's my "impossible" build thread. Without water injection the engine will blow and the turbo will be out of breath at high rpm. Without proper engine management when the water fails, then the engine. If everything works right it should be a blast. I'd just rather try to roll a hard six doing what I've dreamed about for over a year than buy something off the shelf and being like everyone else.

You can still be special if you buy the same kit as everyone else by doing it properly and getting a great result . A very rare feat around here in case you didn't notice!

I wonder what all the little water drops injected pre-turbo will do when they hit the turbine blades spinning at over 130000rpm.

Sounds like an over complicated system that, even if properly implemented, will fail because of the cheap parts used.
Ebay turbos cost 200$ for a reason. It may be smarter to buy an used turbo from a junkyard instead.
A low mount, intercooled gtx family turbo would yield even better results, show way less lag and be reliable.

Why is your dream set up an ebay special?

Dreams are free so why you being cheap?