cookstar

iTrader: (6)

What are these exactly, I believe they increase capacity to 2.3 is that correct?

Also what kind of cost is involved?

Are they preferable to 2.5 conversions.


Car is 02 WRX

cookstar

iTrader: (6)

MrRA

You are correct in your assumption

They increase capacity and inevitably power and torque.

Toda do a stroker kit which increases capacity to 2.2 litres.

It includes a new crank, con rods and pistons.

cookstar

iTrader: (6)

Do you know how much?

Also about the 2.5 what is regarded as the better route to go

The Chief

Ok dont quote me 'cos i'm no expert

it depends on how far you want to take your car - 2.5 should be ok up to 500bhp+ but the big boys use the 2.2-2.3 closed deck blocks because they are a lot stronger aparently.


check out Crawford performance - should give you more idea.

cookstar

iTrader: (6)

Have read a few things about the 2.5 not being as revvy as the 2.3


will look into that site

Spec'c'57

iTrader: (1)

not ANOTHER mod cookie....

Damocell

iTrader: (1)

Scooby Mania do a fully built 2.3 CDB with forged this and nitrided that for about £3000.

Damo

cookstar

iTrader: (6)

Tell me about it.

Overtime a plenty for me

cookstar

iTrader: (6)

Damocell

iTrader: (1)

And double

Found it here £3400 plus vat, seems almost to good not to

ScoobyMania Online Shop

Damo

Neilo

Thats not strictly true anymore, there is a new breed of 2.5 which is closed deck relined from a 2.2cdb.

Strong as any 2.3 out there, with the added capacity though. Will rev perfectly well to 8k and beyond.

The issue is finding a 2.2cdb to start with though

Incidentally i dont have one of these but i know of 3 people that do.

MrRA

You could always have a 2.5 SCD and put liners in it like Ron does at Axis Racing. Will be safe for any any amount of boost then

Neilo

which is most likely what ill do if this one dies...

The Chief

I know someone who is sticking a 2.65 block in his to go the route to mega power.

anyone had experience of these???

Neilo

crawford also have used a 2.8 in the past, they use their 2.7 in thier time attack car....

could always go H6 3.0 like jeff perrin of course...are we getting silly yet?

Lateral Performance

iTrader: (20)

Roughly speaking (depends on exact piston size). Using the 79mm 2.5lt crank,

2.0lt strokes to 2.122lt (Same as HKS, & JUN kits)

2.2lt strokes to 2.35lt (Andy F, Zen, Lateral, Steven Darley, etc').

The ScoobyMania 2.3lt engine is the equivalent of a 2.2lt engine, with a small over bore, using a standard stroke 2.0lt crank. This gives a circa 2.26lt engine.

2.5's can rev' just fine, and the only reason they tend to get peak power early, is because the set up is wrong to get it higher up the RPM range.

For example, If you have a 400bhp turbo, and it makes it's 400bhp at 1.5bar/ 7000rpm on a 2.0lt, on a 2.5lt, it will make it's 400bhp at 1.5bar/ 5500rpm (figures approx).

So at best, you would hope it can maintain the power for a while, before dropping away.


Mark.

borat52

What major would you need to get this built up into a full engine?For example if you had a sti6 could you bolt this bottom end onto it, put a big turbo and injectors on and then get mapping?

Damocell

iTrader: (1)

I think so.

Damo

Neilo

yes you could, phase 2 heads will work fine with them

Area 52 Autosport

There are dozens of areas that will effect response and torque (and reliability) of an engine other than it’s capacity. It’s very easy to be swayed by capacity (and myth) alone.

For example, an optimised 2ltr can make more power at less boost than an ‘unoptimized’ 2.5ltr. While on the other hand a well thought out 2.5 can make a shed load of power and still be extremely drivable at low rpms (something the 2ltr will fall down on).

The ability of a particular set-up is always down to the sum of it’s parts. Running a GT35R on stock heads will cost much less than say, a GT30R with aftermarket cams, verniers and a little port work. While the 35R is capable of <100bhp more than the 30R, it’s the latter set-up that will make more power everywhere in the rpm range, coupled with better spool and throttle response. Similarly there is not much point in spending extra £xxxx’s on buying a sleeved closed deck block/aftermarket crank short motor capable of eleventy billion rpm if you’re going to bolt it to stock heads and a vf34. Horses for courses.

The aforementioned 2.3 (2.26 actual) sleeved motor is designed for high rpm & lotsa boost. We have engines that range from 2 to 3.5ltrs and to put all the possible combinations on the website, I think, would make matters a little confusing (that said, a few more will be going up soon )

For 9 out of 10 of people I would say a 2.5 is the best all-round package

Area 52 Autosport

The motor will ‘drop’ right in, you can use your existing ancillaries. Depending on condition (and budget) it may be wise to buy new oil/water pumps and cambelt tensioner. I would suggest a fuel pump, reg, clutch, FMIC, and (depending on HP target) a dedicated ECU. Not forgetting gaskets, seals, oils, cambelt etc.

Jay m A

iTrader: (2)

Mark, along the same lines with the same example can the 400 HP be made at 7000 rpm on the 2.5 at 1.2bar (approx)?

bigkid

iTrader: (1)

could i just ask the question, to stroke a ej20 is it as simple as changing the crank for a 2.5 crank or do the rods have to be changed as well to stroker rods, can 2litre rods bolt onto a 2.5 crank?

Lateral Performance

iTrader: (20)

Jay m A,

A 2.5lt is certainly capable of making 400bhp @ 1.2bar, and with the right set up, it can make quite a bit more !


Bigkid,

Realistically, you need to use a 2.5lt crank, and stroker rods, and pistons.

Most stroker pistons are designed to go with a longer stroker rod, but if you had a custom set of pistons made, it would be possible to use standard length rods.


Mark.

cookstar

iTrader: (6)

So are we to say the 2.5 can make more power per £ spent?

911

From previous excellent threads in Projects on this topic late last year, I think overall there is little to choose between the 2 liter CDB to 2.35 and a built 2.5.

Seems both can rev to 8K (not on stock 2.5 parts)
The heads both need some chamber work to open to the bigger 2.35/2.5 bores
Both need the bigger turbos and twisted for max results (if that is the goal)
Both need better peripherals (fueling/induction)

Both need the clutches and gearboxes.

Also, the result of the engines is you get a huge hike in torque, in my opinion the real benefit to a fast drivable road/track car.

Finally, after those threads I concluded Lateral and a few others really know their stuff! Listen well to your benefit!

Graham

MJU1983

Correct!