Could It Work for an NA/TT? - Supra/Legacy Turbo Frankenmorph

[schemauk]

My best friends dad has a twin turbo manual Legacy GT (import), which I believe has the EJ20R engine (http://en.wikipedia.org/wiki/Subaru_EJ_engine#EJ20TT). Whether that matters much, who knows - I'm not using the engine, so not so much probably.

 

He's offered me the whole car for £2000, as its currently off the road. He's recently had the engine itself rebuilt, new intercooler, and a couple of other bits, including some sort of big brake conversion. The reason its off the road is because the primary turbo is knackered - he's got a replacement which he said he'd give me if I were to buy.

 

So my question is (I'm new to this whole mechanical side of things...) would it be possible to use the turbo system from this car for a NA/TT frankenstein kind of thing? I understand that I'd need to get some custom pipework done to be able to fit, as well as get a decent ECU mapped... Anything else that could become costly? The turbo's are whatever came as standard on the car. The primary turbo had the markings 'IHI RHF4', couldn't see the secondary turbo.

 

The benefit is that by buying the whole car, that would allow me to break what I didn't need: rebuilt engine, shell, wheels, brakes, interior etc. etc. and could free up some funds to be able to pay for any custom pipework required/ECU mapping.

 

Labour isn't an issue, I have my dad and a few friends who would be willing to help

 

So what do you guys reckon? Is this a possibility, or something I should stop thinking about immediately?

 

If anyone needs any more information, let me know!

[j_jza80]

I cants see it being worthwhile, the turbos are likely on the small side for a 2JZ, and none of the manifolds etc would be any good. It would just be simpler and cheaper to buy some second hand Supra turbos.

 

Has anyone tried fitting stock turbos to an NA?

[schemauk]

Ah, fair enough. Knew there'd be some sort of limiting factor. Its a shame though! Might still buy it just to brake it and makes some money.

 

Still interested about the above question re: stock turbo's.

[listy]

You may be getting confused between NA-t and NA-TT here.

 

When people say NA-t it means a turbo has been fitted to the NA engine.

 

When they say NA-TT, it means an NA engine has been replaced with a TT engine.

 

To fit the stock turbos to an NA engine would probably become more expensive than if you were to buy and fit a TT engine.

[Tsia]

Are the exhaust manifolds not differently shaped for NA and TT though? o.O

[dr_jekyll]

you could drop the tt head straight onto the na bottom , end , that would be a weapon with the higher compression

[schemauk]

You may be getting confused between NA-t and NA-TT here.

 

When people say NA-t it means a turbo has been fitted to the NA engine.

 

When they say NA-TT, it means an NA engine has been replaced with a TT engine.

 

To fit the stock turbos to an NA engine would probably become more expensive than if you were to buy and fit a TT engine.

 

No no, I knew that the NA/TT meant an engine swap - I was just unsure if it was possible to fabricate a twin turbo system onto an NA engine. By the sounds of it so far, not so much Fair enough, will probably just stick to the original plan of saving up for a Whifbitz kit. Was merely hoping to save myself some money!

[j_jza80]

You may be getting confused between NA-t and NA-TT here.

 

When people say NA-t it means a turbo has been fitted to the NA engine.

 

When they say NA-TT, it means an NA engine has been replaced with a TT engine.

 

To fit the stock turbos to an NA engine would probably become more expensive than if you were to buy and fit a TT engine.

 

Really? They should bolt straight up, as so long as you're using them in TTC mode, there's none of the valves to fit.

[Tsia]

Yeah the Whifbitz kit seems to be the way to go, especially with the price reduction with the new manifold. If I hadn't already ditched the NA engine in favour of a TT, I'd probably have gone for one of these.

[Noz]

if the turbos could create positive pressure then i dont see why they wouldnt give some power.

 

i would of thought you may be limited. it wouldnt be a usual setup. perhaps 300hp at best?

 

the thing to consider would be volume. if you could calculate the turbos volume compared against say a T61 you would have a better idea if its possible. smaller turbos would be fine but you just wouldn't get a HUGE return. the T61 is the basic turbo and is very over sized for a standard 400hp.

 

id maybe look into what limitations those turbo's have. you may find a 300hp na-t may be possible. though maybe not the easiest nor cheapest route.

 

without comparison of flow data though don't throw the idea away completely.

 

the biggest decision would be the loss in money against selling them separately. just buying another single turbo may be easier and cheaper if you can get some dosh for them

 

Really? They should bolt straight up, as so long as you're using them in TTC mode, there's none of the valves to fit.

 

head spacing is different, exhaust or intake manifold won't fit.

Edited August 19, 2013 by Noz (see edit history)

[schemauk]

if the turbos could create positive pressure then i dont see why they wouldnt give some power.

 

i would of thought you may be limited. it wouldnt be a usual setup. perhaps 300hp at best?

 

the thing to consider would be volume. if you could calculate the turbos volume compared against say a T61 you would have a better idea if its possible. smaller turbos would be fine but you just wouldn't get a HUGE return. the T61 is the basic turbo and is very over sized for a standard 400hp.

 

id maybe look into what limitations those turbo's have. you may find a 300hp na-t may be possible. though maybe not the easiest nor cheapest route.

 

without comparison of flow data though don't throw the idea away completely.

 

the biggest decision would be the loss in money against selling them separately. just buying another single turbo may be easier and cheaper if you can get some dosh for them

 

Ok, looks like some calculations may be worthwhile then... I wouldnt necessarily be looking for crazy increases, 300hp sounded about what I would have expected anyway. Need to find out the exact specs of the turbo's.