68 69 70
nocones
nocones PowerDork
7/31/24 2:10 p.m.
adam525i said:

Is 4-500 hp your goal here or is it just nice to have that headroom built into the block so at 300 hp you can just enjoy the car? Is there a reason the EZ30 is an option but not the newer EZ36?

No, based on performance with ~200WHP I think anything beyond 300WHP would be stupid.   I want the headroom of "reliable at 400HP being asked to do much less".  

The EZ36 has some changes that make it more challenging to use.  It's DBW only, which is managable, but also has offset connecting rods which make aftermarket availability lower and many in the Subaru Trackday community doubt their reliability for high RPM track work.  The EZ30 with it's shorter stroke runs traditional rods that don't have these compromises and is available with a Cable Throttle body.   It is also the EZ recommended by the track community. 

For sure whatever engine goes back in is getting much more dyno time and a much more gradual introduction that will find issues before they become catastrophic.   I think putting the WRX motor I have in and running the car a a few autoxes and some lower pressure track events is probably a good approach then do an IAG type motor over the winter unless I decide to do a swap of some kind.  

 

Shavarsh
Shavarsh Dork
7/31/24 3:54 p.m.

An expensive engine that will provide the power delivery you have experienced and are happy with, but without reliability concerns seems like the right choice from here. You could spend the same amount prepping another engine and rebuilding lines/wiring, and end up with a different power curve that may change the feeling in the car (v8/K). The car has also been designed around servicability of this engine. Sounds like you're on the right track. 

Pete Gossett (Forum Supporter)
Pete Gossett (Forum Supporter) MegaDork
7/31/24 4:24 p.m.

In reply to nocones :

Considering how great the car felt before the engine let out the magic smoke, it sounds like spending the $$ for a more bullet-proof version of the engine is the right long(ish)-term goal. 

I agree with going back to N/A since you already have the engine & it will allow you to still enjoy the car, while also not feeling like you have to spend $$ immediately. 

sleepyhead the buffalo
sleepyhead the buffalo PowerDork
8/4/24 2:37 p.m.
nocones said:

The reality is there is an ea$y answer.  IAG and a few other companies have near bulletproofed the EJ20/25 for ~400-500 HP race applications. 

I have the oiling solution already (fully baffled pan with windage tray, special pickup and ported Oil pump).  

It's just not cheap.  It's about $6000 for a new shortblock and to rebuild and use the built EJ25 heads that came off the EJ257 that failed.     

It's just that is a lot for me to spend compared to my typical way I do projects.  It is likely I will do it though, as it is literally just a bolt in affair at this point.  

The other options are:

$0 - High mileage WRX motor in garage (sunk costs already own).

$1500-2000 - EZ30D Flat 6.  Advantage, ~200whp still NA.  Not a high $ motor build.

$2000-3500- KSwap.  See EZ30 for basic summary.  Requires $1300 adapter kit.  It doesn't seem that the K engines are inherently more reliable (at least 1 lets go at every Gridlife event) but they are everywhere, easier to build then EJs, and inherently a more capable motor then the EJ.  230whp NA is apparently possible in a K24 with fairly limited changes to junkyard motors.  

[...]For the power goals of the project the Subaru Transmission seems capable when the input bearing isn't broken. 

re: K24's.  while "they're everywhere", from what I understand, the good ones are getting "used up" some, and motors one used to be able to find for $1800 are not $3k.  Dunno if it's been explored much yet, but I wonder about the K20C4's out of the 2018+ Accords for swaps?  they seem to be on car-part from $1800 up?

other thought, since there seems to be a "value"/"appreciation" for the fact that LMP360 is "all Subaru" still.  Any thought to the FA motors, if the "easy button" on the EJ's is too tough a pill to consume?  I recognize there's mixed opinions on the strength of them; but you've already done some of the hard part of engine swapping by having the Halltech in there, yes?

either way, enjoy your time away... although I'll agree that you not let it go too long.  finding ways to put little bits of time in on it every week... maybe especially not on the engine... finding some small improvements/victories could be a good direction to take with it while the heart issues are evaluated.

vwcorvette (Forum Supporter)
vwcorvette (Forum Supporter) PowerDork
8/4/24 3:41 p.m.

Maybe check and see what Vermont Sports Car has lying around?

nocones
nocones PowerDork
8/18/24 11:12 p.m.

Alright so I had some time away from the car to have a think.   I strongly considered all of my options and nearly convinced myself to just put it back NA.   But I know I would regret not finishing the vision and spending some time turbo on this thing.   I had some conversations with IAG, got a quote from a local engine builder and generally became comfortable that I just needed to spend some money to get the right engine in.  

My plan was to buy a IAG 550 shortblock.  This is forged internals, stock displacement, race spec bearings and all the little build tricks they do to make a reliable EJ.  The 550 level is an open deck block.  It would cost quite a bit, and I would spend another probably $2500 to upgrade a lot of my supporting mods to support the quality of the engine.   Things like a better intercooler, a real Air Oil Separator.  I also would need to install rebuilt heads head gaskets/etc.  

But then Kevin came off the top rope with a steel chair and offered me his Legacy GT at a very fair price.  It has an IAG 750 closed deck block in it.  It has all the necessary quality go fast parts to make reliable 400-500 HP.   It also is attached to a pretty decent Legacy GT that will give me opportunities to upgrade some other parts on the LMP360 and then have options to recoup some of the costs of this engine adventure.  

So here is my new LMP360 Engine.   It will make enough horsepower to scare the crap out of me.   It will be capable of sub 5lb/HP.   But I will ask it for less because I'm afraid.  Realistically HP will be limited by reliability of the 5MT transmissions. 

I am not going to rush to put this in.  I am going to shoot for having it at Time Trial Nationals / UTCC.  But ONLY if I get it tuned by a professional Subaru tuner before the event.  If it doesn't happen it will be ready for next season.  

 

Piguin
Piguin Reader
8/19/24 4:39 a.m.

Glad to see a solution appeared and the LMP360 EVO III is now moving ahead.

 

And I am also slightly scared about the hp/lb, but thankfully from the safety of my home. Doubt you'll feel it lacking in power this time around.

Recon1342
Recon1342 UltraDork
8/19/24 4:04 p.m.

LMP360 is gonna be a rocketship at this point. 

F1 cars run about .6 hp/lb, just for reference.

Sub 5lb/hp is incredibly impressive for a homegrown race car.

68 69 70

You'll need to log in to post.

Our Preferred Partners
rA8ypSw32IBpE85SucdTFqDlGs0qTyGSZQOVpThCM3LjOZJUlBd7RAxhMmKyokSx