blast from the past this coming back up.

tell you one thing it is amazing how time flies looking back at the start:eek:.

Following the thought that the cambelt tensioner was at fault, two further engines were built which exhibited the same noise issue and a cause cannot be established. So, the linered CDB 2.33-2.36 litre project is shelved on my car, although I gather the same engine is working well for David Wallis and Trout. Those are the facts of the matter, I don't want a long discussion about it here especially because of various political considerations, email me if you want to discuss it, time to move on to the new plan.

The present plan is a 2.5 litre US STi block with semi-closed deck block and the original rods and pistons, using abut 8.6-8.7:1 CR with my flowed STi 5 heads. There are fascinating results from the US with this block. I still am going to shoot for 450 BHP and 400 lbft if I can easily achieve it, although some wisdom recommends a maximum of 350 BHP on this engine. However, apart from looking at the internals I am not aware of anyone tuning one beyond 350 BHP and breaking it yet in the UK to see what happens. Needless to say I am going to tune it quite carefully and progressively but I'm not going to pussyfoot about with it. I still have a spare 2.0 ODB and heads in good nick to fall back on.

Planning to use water injection to keep the bore temperatures down, headers, 740cc injectors, JECS remapped (will see how I get on re MAF voltages), closed loop knock control, 20G, FMIC, APS induction with changed filter (APS elbow keeps the MAF voltage sane). I plan to limit boost to 20 PSI ;)

Few issues to sort out with the hardware on the car before it is up and running, could well be another week, will do a 1000 mile break in and then change to semi-synthetic and establish baseline results at low boost.

John, I am sure that the EJ257 shorblock won't let u down ;) ..... BTW what headers will u use ?

Carlos H.

Gruppe S with the large bore uppipe.

what turbo and what cams?

David

STi 5 cams, TD05/06 20G. Andy got 440 BHP at Star with this turbo so I think it will do, especially since my projected boost is where it flows best.

john banks

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Posts: 9191
From: Scotland
Registered: 04-11-2000
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posted Monday, June 23, 2003 17:20


Lifting engine out

look at it this way john, you must at least have the record for number of engines in a car :rolleyes: ,2litre,2x2.33's,2.36 and now a 2.5. keep going at this rate your going to have more cc's than pat ;)

It will indeed be good to see if the 2.5 shortblock can stand the pressure.....

it will also be alot cheaper to get the 2,5shortblock rather then building another block....

Just go for it.....

Skassa

T-uk,
Don't speak too soon! Next he'll be trying to persuade you to get a German 5.0l in there. The problem is that he feels it needs a turbo :rolleyes: :D

John,
Pleased you have chosen the 2.5l route - hope it goes well for you!
Any chance it will be back before Star? Speak to you soon.

callum

john,

Do you not think the exhaust side is too small for the 2.5?

David

I believe exhaust sizing is related to power not capacity. It does not "know" the capacity of the engine. Some think I am barmy going for 450 BHP. Andy has proven this turbo to 440 BHP on a conservative rolling road. My Delta Dash results were suggestive of similar, but it struggled on the dyno with multiple runs and I had to run silly boost because of not having headers. If it does 420 at Star and 450 at Well Lane I won't cry, and also probably not change the turbo. It won't be ready for Star I don't think Callum as it is quite soon?

Why the "large bore" up-pipe John?
Is it purely because of the larger capacity?

Alan :cool:

John, Pete's SIDC day at Star is on the 9th November so still some time for a rebuild.

Callum :D There are numerous bridges to leap over before readiness.

Large bore, just to say version 1 with the rather large up pipe. If keeping 2.0 I would try to swap it to the smaller bore uppipe and headers that were supplied in the group buy as they did seem to subjectively help T-uk's car below 4000 RPM in 2nd gear for spool up and did not lose him power at the 280 WHP level on Delta Dyno. What I could tell of spool up on the 2.33 was that it would be fine with these headers and the 20G - plenty of low down torque.

Good luck with this build. Hope the misery you have had to endure this last four months is soon behind you.

Good Luck John

After talking to Carlos I think I will be going down that road my self ;):D


Jan

It is alive and purring sweetly :D :D :D :D :D :D :D :D

When I get it back :D and run it in I will then change the box and engine oils from basic mineral stuff, fit the J&S Safeguard and map it with the MAF sensor and 550s at low boost first of all. Then synthetic oil, Redline shockproof, 740s, water injection, MAP conversion, induction kit change and higher boost.

What CR did u go for ?

Carlos H.

The one you calculated is what I asked for. Anything from 8-9 would be fine by me.

Nice one JB :) What you doing with your old CDB and 2.5 crank ? I'm sure I could find a use for them ;) :)

Andy

No parts available Andy sorry.

This was posted some time ago:

If I wanted to use the stock US 2.5 STi (EJ257) shortblock with the EJ257 oem 0.8mm gasket with Phase 2 heads the CR should be:

deck clearance volume = 2.96cc
dish volume = 22cc
.8mm gasket volume = 6.22cc
head volume = 49.6cc

Total compressed volume = 49.6+6.22+22+2.96 = 80.78cc

Total swept volume = 614.28cc

CR = (614.28 + 80.78) / 80.78
CR = 8.604:1

:D

Carlos H.


[Edited by carlos_hiraoka - 11/11/2003 2:47:44 AM]

Good news :)

Keep us informed about the progress JB

Will go down that road myself I think :)


Jan

On sg72's STi 5 with FMIC, headers and 20G at Star the other day it did 403 BHP and 337 lbft at 1.4 bar held :D

A few back of envelope calculations since I am using similar spec but 2457 (IIRC) rather than 1994 cc (ignoring the effects of compresssion and higher efficiency at lower boost vs the effects of demanding a lot from the STi 5 heads I will be using albeit ported):

2457/1994 * 2.3/2.4 * 337lbft = 398 lbft at 1.3 bar
2457/1994 * 2.2/2.4 * 403BHP = 455 BHP at 1.2 bar

I wonder, I just wonder :D

so do I :D

Running std cams?

David

John

A quick calculation in my head;) suggests you would need to run 1.311557789 bar midrange and 1.175824176 bar top end to achieve your original objective of 450bhp/400lb-ft torque :)

Andy

Superb result :)

BUMP!!

Any news yet?

I don't have the car yet.

just been informed that car is going great and has done 5000miles,12rally stages,8 trackdays and run high 11's at the pod:D

brakes,dampers and clutch all sha99ed so it will be back next week as soon as AA recovery vehicle is booked:rolleyes:;)



































please note use of smilies since I'm joking and bored.