Which engine or which motor to put on

[tcyclone1]

Hi,

I'm relatively new for 818, currently running with EJ251 (2.5L non-turbo) whose condition is not good. (Some thing like knocking sound over minor load, engine oil not drained all (I believe this since only about 2.5Q drained from FULL line of dip indicator), low torque on high RPM range)

I want to put better condition engine or electric motor on it, but cannot decide due to lack of information. My goal is 50/50 on track and high way, and durable setup (I cannot spend too much time on maintenance/optimization.)

Currently considering 2006 WRX (or any other newer WRX/STI) or Tesla motor (I'm quite comfortable with electricity.)
Could anyone give me an advice what is the pros and cons(what kinds of difficulty) for some engine choices and motors?

Thanks,

Zay

[Bob_n_Cincy]

Hi,
I'm relatively new for 818, currently running with EJ251 (2.5L non-turbo) whose condition is not good. (Something like knocking sound over minor load, engine oil not drained all (I believe this since only about 2.5Q drained from FULL line of dip indicator), low torque on high RPM range)
I want to put better condition engine or electric motor on it, but cannot decide due to lack of information. My goal is 50/50 on track and high way, and durable setup (I cannot spend too much time on maintenance/optimization.)
Currently considering 2006 WRX (or any other newer WRX/STI) or Tesla motor (I'm quite comfortable with electricity.)
Could anyone give me an advice what is the pros and cons(what kinds of difficulty) for some engine choices and motors?
Thanks, Zay

Zay,
I'll give you a rough estimate. I have built a turbo 818s, owned a couple of NA Impreza, Built an electric car, and designed many other electric vehicle motorcycles to semi-trucks during my career.

1. Fastest, lowest $, and lowest knowledge solution.
Used running NA engine < 150k mile about 2K.
Option a new NA OEM short block. 2-3k
This will be about 150 WHP and adequate for a track day.

2. Medium time, Medium $, and medium knowledge solution.
Used running WRX or Forester XT <150k about 4-5K
You will need an engine, wiring harness, dash cluster, Engine ECU, and some other donor stuff.
You will need to get up to speed on troubleshooting wiring.
My 195 WHP is a lot of fun at a track day.

3. Most time, the highest $, and maximum knowledge solution.
need a Tesla inverter/motor/gear combo. WAG 10-15k
Need battery pack 10-20k (a tesla pack would be very difficult to integrate into the 818s frame). To my knowledge, no one has done this.
A controller that integrates Battey BMS, Charger, control, and Motor inverter. 5K
Knowledge if you don't farm it out, Embedded software engineer, Electrical engineer, Mechanical engineer.
You must be comfortable with 400 Volt DC circuits. (THIS CAN BE DANGEROUS)
This car would be difficult to do a track day with. Need to charge between each session without fast charge capabilities would be impossible.

This one of my favorite video's, Mitch Driving my 195hp 818s chasing a 600 hp ford GT.

https://www.youtube.com/watch?v=xVEqS3Gs9SM

Bob

[tcyclone1]

Hi Bob,

Thanks for a reply. I had a first track day with this and so much disappointed with acceleration and handling as well (maybe tire/alignment not good?), so I think I got to do something quickly. Since that was non-turbo 2.5L engine, next easy solution looks like turbo engine. I found WRX 2006 engine nearby and wondering how much change do I need, do I need even wiring change? what else should I ask over ECU/Dash cluster?, do I need transmission?or if it is better to find newer WRX or STI engine.

For the electric conversion, it looks like straightforward for me (since I'm elec engineer and also worked on FW(embedded SW) a lot.) Just I don't have much info on the motor(maybe 3 phase motor ?), motor power inverter, inverter controller logic. I can use one of my EV(Volt, Leaf) as battery/BMS/charger donor.

Zay

[Bob_n_Cincy]

Hi Bob,
Thanks for a reply. I had a first track day with this and so much disappointed with acceleration and handling as well (maybe tire/alignment not good?), so I think I got to do something quickly. Since that was non-turbo 2.5L engine, next easy solution looks like turbo engine. I found WRX 2006 engine nearby and wondering how much change do I need, do I need even wiring change? what else should I ask over ECU/Dash cluster?, do I need transmission?or if it is better to find newer WRX or STI engine.
For the electric conversion, it looks like straightforward for me (since I'm elec engineer and also worked on FW(embedded SW) a lot.) Just I don't have much info on the motor(maybe 3 phase motor ?), motor power inverter, inverter controller logic. I can use one of my EV(Volt, Leaf) as battery/BMS/charger donor.
Zay

You said" so much disappointed with acceleration and handling as well (maybe tire/alignment not good?),"

You have a very well balanced 2000# car with a lot of rubber. Alignment, suspension setup, and tire choice are on you. This car can be made to run on rails. Changing your powerplant is not going to fix this.
Going electric will add 1000 lbs to the car. This seems to be counter-productive to your goals.

Maybe I'm not understanding your goals. A track day is all about driving YOUR car to the limit and improving your ability. It is not about being the fastest guy on the track. It is not a race. There are a lot of 130 Hp NA Miata's out at track days having a lot of fun.
Bob

PS: This is a picture of one of my 06 2.5L NA impreza. It was over 4000 lbs with the 2 lug nuts in the seats. It had really bad body role, did not rotate well, but was a blast to learn how to drive on the edge of its capability. The second picture in my 818 in a 1.2G turn.
134836 134837

[tcyclone1]

You said" so much disappointed with acceleration and handling as well (maybe tire/alignment not good?),"


Well, I think the amount of fun could be relative measure. When the car spills oil from unknown hose/plug and smoking with oil dripping on exhaust on a track (and getting black flag due to the smoke), while engine makes knocking-like sound with low torque which cannot pass even 130HP stock-like NB. Also having spun on the corner where I used to run 10MPH faster with twice heavier car was not fun at all personally. (Actually it was clearly my worst day on track, 3 times of black flag, 2 times from oil/smoke.)

Alignment/scaling will be changed if I change the engine, so that's why I thought engine first and then scaling/alignment. Now the immediate question for me is which year turbo engine will fit the chassis, and what additional parts are needed except the clear parts (ECU, wiring, dash), and can I reuse non-turbo's clutch/transmission.

Zay,

[Ajzride]

If you are persistent on adding a turbo engine, rather than just fixing your current engine, then look for a 2002 WRX Turbo. You will need the new engine, the ECU, The engine side wiring harness, and the gauge cluster. You should be able to reuse your transmission/clutch. You will also need new exhaust.

[Just puttering]

Why are you taking a car that is knocking, dripping oil and blowing smoke to a track and then trying to evaluate how it is handling?

from what ive read on the forum, if you are going from front engine to rear you need to adjust your driving style on the track!

[tcyclone1]

If you are persistent on adding a turbo engine, rather than just fixing your current engine, then look for a 2002 WRX Turbo. You will need the new engine, the ECU, The engine side wiring harness, and the gauge cluster. You should be able to reuse your transmission/clutch. You will also need new exhaust.

Thanks for giving a specific advice, do you have any reason recommending 2002 model year?
In other words, why not 2005 WRX or 2006 WRX?

[tcyclone1]

Definitely the car didn't spill any oil until the track day. Oil leak seems related with WOT, hot temperature and/or high lateral force. The knocking-like sound doesn't happen in near WOT, so I thought it should be OK, and this seems not related with oil spill.
The area that I'm not that much satisfied on handling is that the steering feedback is strange to me. Maybe it is due to the steering system that was designed to have power-assisted, but power-assisting is removed?

[Ajzride]

https://thefactoryfiveforum.com/showthread.php?5966-De-powering-the-steering-rack-plus-more-to-come-on-rebuilding-wrx-parts