Subaru Engine Swap :-o

Jim > Amsterdam · 03-08-2007, 12:08 PM

Don't kill me... and I know there was a short post on this before (Porscharu).

I'm trying to make a super lightweight 912 conversion - into a 911 RS/RSR inspired design. I'm 2 years into my project and have converted many body panels to carbon-fiber.
I recently rode a VW beetle with a Subaru engine and modified exhaust system. It was fast to say the least.
The Subaru engine is a Boxster layout, and shares the Porsche coupling plate.

And now to my question...
What is the best option for my fast street car?

a) Modify my 912 engine even more (I have shasta pistons, Bursche sytem - now 120bhp)
b) Install a (heavier) SC engine : 205 bhp
c) Install a modified Subaru engine (light, boxster - 250 bhp)

My car was not in original condition when I bought it, so 'pure' or 'original' is not an issue. The issue is 'FUN' for your $$$'s....

randywebb · 03-08-2007, 12:19 PM

For a super lightweight motor, why not use an RX-7 or -8 Wankel?

How much does the Subaru motor weigh (and is this the 4 cyl or the 6??)

If you use an air cooled motor, you will need to run oil lines to a front 'radiator.'

If you use a water cooled motor, you will need to run water lines to a front 'radiator.'

Do you want 6 of one? Or do you prefer half a dozen of the other?

You might want to collect all the conversion threads using a search and link them here....

Cory M · 03-08-2007, 12:23 PM

has been done on 914's - do a search on 914 club. Could be a lot of fun if you got one of the turbo WRX or STI motors.

Facey · Facey's Garage

i would prefer to see a 2.2-3L flat six in there, breathing through some webers or PMO's could be a ton of fun.

however i will agree that the scubby engine (if your talking wrx-sti) could make more power, don't fool yourself into think it would be lighter.

radiator, inter-cooler, additional mounting brackets.... it is alum however so its lighter then some other options.

best bang for your buck, in terms of power is still undeniably a small block, like a chev stroker 383, use a 930 4 speed trans and its an crazy, stupid fast car....rev to 7 and your going like 70mph in first..... 3 gears to go....

the scubby engine seems like a wierd option to me, the only reason it is suggested (ever, IMO) is because its a flat design. It is actually inferior to me evo engine, especially in terms of reliablity....

there ya go, IMO:
nice period correct flat-6, and nice 250...
serious bastard powerplant , 383...easy 500.....
then if you wanna go jap, i'd go the route of evo based power...i've seen it done, something to the tune of 448rwhp.... kinda wild...

Jim > Amsterdam · 03-08-2007, 12:27 PM

I recently met a guy who was implanting an Impreza 350 bhp motor into his 911. He had a big box full of cables and wires, he was a long time busy with it... he suggested a more simple Legacy engine of around 230 bhp.

Jim > Amsterdam · 03-08-2007, 12:37 PM

...The Darkside does have more power! This Beetle was fitted with a Subaru turbo engine in place of the more traditional flat four.

Jim > Amsterdam · 03-08-2007, 12:44 PM

Just found another reason...

"PPJ RACING's unique, quad-cam,
Subaru-headed turbo Beetle"

http://www.tsrdragracers.co.uk/index2.html

Facey · Facey's Garage

that picture above is mis-labeled, it makes little to no sense that it would have that 11 blade 911 fan , which is used to aircooled the cyclinder heads, and the water pump...which implied wate to cool the heads....

and all those beatles are nasty-ugly creations that only a maker (mother) could love....

the rx-7 engine is a good idea, will have a simliar nature to the old school 2-2.2L F-6's...but with more modern hp numbers.

atlporsche · 03-08-2007, 12:54 PM

I've got the porscharu. it's easy. I've got the 1.8L NA in a '67 912 body. flat four for flat four you know? The weight isn't much different than the 912 engine. the EJ engines come in at about 297 lbs. 912 motors were 250 lbs, 911 engines were 450 lbs.

what's the flat 6 in the pic above?? it almost looks like an SVX EG33. Those sound AWESOME when they've got the right exhaust on them.

sjd

Jim > Amsterdam · 03-08-2007, 12:57 PM

What EJ engine did you install? Did you do it yourself?

I once saw a 911 with Legacy motor and custom motorbike exhaust system. The sound was amazing. Performance was stunning..

tahoe_snow · 03-08-2007, 01:12 PM

What do you have to do to get 230bhp out of NA EJ25? Those things only make about 165bhp stock. Personally I think the 914 WRX conversions are pretty darn cool.

Facey · Facey's Garage

lol, 911 engines are 450lbs... when filled with lead..
me and one of my friends, neither of which are huge guys (180-190 6') where able to EASILY move around my 3.5L with its complete induction and exhust system. no tranny...but i was able to move my 915 with some heavy, by myself, grunting...

some of these hp numbers which are being tossed around are 'high', getting to the non-car guy more for ego chat stage.

the scubby engine will NEVER, sound or feel as nice as one of the true porsche engine.

i have nothing wrong with hot rodding, i encourage it. but make it cooler and more exciting, not put some non-performance engine in it.

the svx engine might be okay... but... its even kinda old tech. If your gonna spend the money, get a wrx or a STI engine...

my vote is still for a single turbo wankel....

Rearden · 03-08-2007, 01:20 PM

Keep it in the family and build one of those EFI twin-plug 356SC/912 hot rod engines. You can get 150hp out of it and it will be light. Then again, I'm a purist.

rammstein · 03-08-2007, 02:38 PM

Don't waste the time trying forced induction on a Renesis (RX8) powerplant. Its still not working perfectly for even avid Wankel guys.

atlporsche · 03-26-2007, 06:12 AM

Facey, c'mon down and see my EJ18 then. It sounds just as good as my 912 engine EVER did, has 20 more horsepower, and is a twincam (which, in reality, makes it sound BETTER). in 2000 lbs of SWB, it's pretty fast, moving to the EJ22 140 hp engine would be the ticket.

230hp was stock horsepower for the 2.5L turboed Forester engines (basically a detuned STi block).

Porscharu makes believers out of naysayers, and costs 1/10 of what a twin plug 912 hotrod engine costs. I've seen the twinplug 912 engines, and they're really cool, don't get me wrong, but I don't have that kind of cash.

911 engines are heavy...50% more than a 912 engine...which starts them at 375. I've seen the weight quotes as high as 450 wet.

sjd
also building a Miata powered MGB.

Porsche virgin · 03-26-2007, 06:43 AM

Hey atlporsche, the porscharu forum link in your sig doesn't work.

id10t · 03-26-2007, 06:53 AM

Type 4 VW engine... of course, your problem is going to be how fast for how long.... You could just build the 912 up "more". One of the 912ers from rennlists forums (Harry) had his engine redone by a well known builder a couple years ago, around 130 horses, should give long street life.

(If I were to swap out the engine in my 356C it would be for a milder Type4 - around 100hp or so)

Shuie · 03-26-2007, 09:01 AM

Cool thread. Subscribing....

FWIW, A 3.0 Porsche longblock weighs close to 400lbs. Fully dressed and plugged into the car the entire engine is closer to 500lbs.

oldE · 03-26-2007, 09:56 AM

"that picture above is mis-labeled, it makes little to no sense that it would have that 11 blade 911 fan , which is used to aircooled the cyclinder heads, and the water pump...which implied wate to cool the heads...."

Facey,

I suspect that engine has air-cooled cylinders and twin cam water-cooled heads.

Does kinda seem like overkill, though, don't it?

Les