My engine in my '96 WRX is abit poorly with what looks like a cracked piston ring land !

I had decided to go with a new 2.5 bottom end but i've heard the 2.3 conversion is better ?

I have all the supporting mods except a decent turbo to get the most out of whatever I choose but just want some more info on the 2.3 before I make a decision and spend the money.

Any advice will be appreciated.

 

it all depends on what your after ?
i have started a thread on building a 2.33 have a look P1 Web Owners Club :: Warning, may contain nuts!

 

also look at martys p1 its a 2.1 and 550ish

 

2.5 has far more torque all depends what you want??

 

2.33ltr is an expensive build, a normal 2.5ltr isnt

 

Just want the best I can get for the money-Been quoted £3000 for the 2.5 conversion or the same price for a 2.0 with forged everything capable of handling over 400bhp.

I haven't heard of the 2.1,2.2 or 2.3 conversions until today !

 

Bargain or what?

2.5L OEM STi Short Block & Gaskets Flat4online.co.uk Subaru Impreza Mitsubishi Evolution EVO Walbro Fuel Pumps Injectors Intercoolers

 

Take that 2.0 litre engine. Much better for "bhp" than 2.5 litre.

 

2.0 leads the time attack chamionship, where are the 2.5s

 

you will need to add a couple more thousand to a conversion to 2.33ltr

 

Yeh I was going to get that block but the tuner who I want to go with(I won't name them but they are very well known and respected on here) won't fit custmomer supplied parts !

I've also been told by 2 tuners that the standard 2.5 sti block is only safe for around 340bhp,anything over that needs forged pistons,rods etc plus oil cooler with remote filter.

 

I have 2.5 litre STI and can confirm that . Also problem is head gasket and screws.
Keep on with 2.0 litre, and you won't regret.

 

I was under the impression that in the states the 2.5 engine is reguarded much more highly than the 2.0 and is tuned to huge power outputs, Be interesting to hear from any americans!

 

If I go with the 2.0 litre,what turbo would be good for getting good power without too much lag and what power could I expect with all the supporting mods that I have:

550cc Injectors,Front mount I/C with hard-pipes,fuel pressure reg,255 fuel pump,Apexi power FC,Gen II spec ceramic coated headers and up-pipe,Hayward&Scott stainless exhaust system,pipercross induction kit.

 

IHI VF34, I think it's ballbearing, up to 340 BHP IMHO.
Garrett GT28R 53MM 62 TRIM 300HP
Garrett GT30R 76.2MM 84 TRIM 500 HP
Garrett GT35R 82MM 84 TRIM 680 HP

 

I have a TD05 16g with roller bearing that was running around 340bhp so i'd be looking at the Garret GT30R-How much is that ?

 

$1145.00 fob U.S. only turbo charger (not kit)

 

dont use the pipercross filter find a kit like RCM or GGR that is based on a k&n.

 

What's wrong with the pipercross ?

 

What does TRIM stand for ???

 

pipercross is a foam based filter and the k&n is a meshed type !

 

Is foam no good then ?

 

On a built 2.0 designed for fast road use I would advise against a GT30.

A MD321H will be perfect for over 400 with quick spool and little lag with relatively low boost...
With your supporting mods you should be looking at around 420bhp with the MD321H. The T version will get you more power, however the lag and spool is not as good as the H.

Bigger is not always the best option Turbo wise.

If your on a budget than an 18G can suffice on high boost.
The forged internals can handle the higher boost levels and you can achieve a very fast road car. I am running an 18G on a built 2.0 mapped to 1.7bar the car achieved over 400 on V-Power. The mid-range is phenomenal and for the road it is perfect.

 

Trim is an area ratio used to describe both turbine and compressor wheels. Trim is calculated using the inducer and exducer diameters.
Example:
Inducer diameter = 88mm
Exducer diameter = 117.5mm
Trim = Inducer2/Exducer2
Trim = 882/117.52 = 56 Trim
As trim is increased, the wheel can support more air/gas flow.

 

Mmmm 420bhp,that sounds good

It's all down to cost though-what's an 18g cost compared to the MD321H ?

 

2.5's make great road engines, lots of low down and mid range grunt, something a 2 litre struggles to match, but it's not a great screamer, so if you want low gearing or plan to use the car for drag racing it's not ideal...unless you're prepared to spend mega money

A 2.33/2.35 makes a storming track and drag weapon but it cost a lot to build properly. Bascially a good 2.33/2.35 is made from 2.2 litre closed deck block, or a relinered 2 litre closed deck block, fitted with a 2.5 litre crank and custom rods and pistons....that's where the cost comes in. To do it justice you should also go the whole hog and fit custom heads, cams etc big money, but big big power and the ability to rev too.

A stock 2.5 EJ257 bottom end can give a reliable 400/400 with the right turbo and supporting mods, but if you want to future proof things the pistons at the very least need changing, otherwise yoi'll be experiencing failed ringlands again, with the pistons replaced with forged ones then 450/450 is about doable...to go beyond that level the rods need replacing with stronger ones. 3k is about right for this sort of work, the parts alone add to over 2.5k

Believe me I've explored all the options, I should have built a 2.33, but couldn't afford to, so I've settled for a 2.5, which with the help of a few friends was finally assembled at the begining of this week

Whatever though you'll need a stronger transmission!

 

A "built" 2 litre with an MD321H will be the best road-going option for you on a decent budget. Although a "built" 2.5 litre shouldn't be much more expensive and will give much more torque.

My built 2 litre runs 504bhp and 486 lbft on race fuel - using a MD321T turbo

 

the foam has been known to come off in little pieces, you dont want any of that getting sucked into your engine !

plus the k&n is much better top quality, buy one from RCM and compare it to the pipercross and you will see the difference

 

Terry, is this the engine you've now sold??

 

By the looks of it you have had some great advice on here. I bought my car with a 2.33 engine, it's a closed deck block with forged crankshaft, rod's and pistons, I understand the vrank was 3k alone so I can only guess what the complete build cost I guess tha main advantage is you can rev the **** off it, my redline is set @ 8k but i have a small hybrid turbo running about 300hp spools up quickly, strong midrange but does run out of puff over 6k im thinking about a much bigger turbo but im worried about the lag, i guess there will always be a compromise between lag and top end power, depends what you want, i would have thought a 2.5 would be ideal for fast road use.