Shaun

Peanuts.... would you like to think again about that comment!

StickyMicky

so much conflicting advice!

its a minefield

what i have just "had done" is a 2.5 swap into my car + an apex ecu

rough current engine spec
V3 1997 wrx

2.5sti bottom end
ported headers
3" revolution exhaust
zerosports upipe
silicone inlet
sti8 fuel pump
ported (to the zerosports upipe) and polished td05-16g
stock 440 injectors
stock 97 wrx top mount (same as the sti one)
cometic 1.6mm gaskets

i mapped it to run 1.6bar peak on the td05 and in 5th gear it is holding approx 1.2bar at 6200rpm (when i backed off)
in true ghetto style i am controlling boost with a simple dawse device, although i had to drill out the bleed hole a bit as it was undrivable with it stock (boost was coming in far to fast and was a PITA to drive around smoothly) had a play around with the apexi and the stock 2 port boost control but hated it.

injector dutys at this point are at about 97-98% so not really recommended, but it drives like a nice lag free weapon and i cant force myself to turn it back down
will probably fit some 550`s when i can be arsed at some point

it drives with a max knock count of about 20 on the commander at 150mph
anything under 100 has the knock count at about 7/8 max

i have no doubts i could be a bit more ruthless with it and i understand that the TMIC is not restraining things at high speed, but it never gets used over 100 any more, its never even used hard any more 99% of the time, so for me at the moment, its simply not an issue

what i can say, is that
1. i ran my injectors at 90% duty for the past 4 years without issue on the 2 litre, yours may not like this! but mine "seam" ok
2. over 100mph the top mount is not working very well and det noise starts to increase, i had to pull some timing and add some fuel to help protect it at high rpm/high loads
3. had conflicting advice over how much boost a stock sti bottom end can take, the yanks claim about 23psi tops (approx 1.6bar?) people on 22b.com are saying over 1.35bar is a better idea.
4. they are supposed to destroy gearboxes quite easy!


last time i had my clutch changed i was a bit skint and went for the smaller UK spec exedy one (225mm iirc?) its not designed for lots of torque but at the moment seams to "just" be coping, i have no doubt that if i had a more aggressive clutch, i would have killed the box by now, but i am very sympathetic with the gearbox anyway as it now has 125k miles on it LOL

it still gets the odd drag start when these things must be done but i understand that it will probably be the weakest chain in the link next time i have the clutch changed.

Shaun

We are talking about a forged internal, standard 2.5 block cased bottom end here. The fact is, they can and will take a lot of abuse. How much for how long.... who knows. But mapped properly, with the right ancillaries, they certainly seem up to the job in a number of various applications. I am not the only person running in excess of 500/500, in a car that is used and used hard (or harder than a road car anyhow). Obviously I am wary of the block and appreciate cylinder pressures maybe an issue, but then I take stock of that and try to spec things with this in mind. Headgaskets are another issue, but I hope the block mods I have had done will stand me in good stead on that front (so far so good).

Who knows, but I am not convinced even a linered block would give me the confidence to throw all sorts at it. A closed deck 2.5L may be a different story.

Fai17

iTrader: (2)

hmmmm...interesting read

StickyMicky

shaun, i thought the OP had bought a stock 2.5sti bottom end from RCM ?

was not aware it was an all singing and dancing uber forged one ?

Shaun

Peanuts

iTrader: (15)

Only if you offer to guarantee my lump for next season

Shaun, we all know you're the exception to the rule only kidding, its true there are big power 257 blocks, but its also true there are 257 blocks that **** themselves under high pressure.
So the safest thing is to find an acceptable medium and that seems to be about 1.6 bar.

Anyway, I'm not listening to you until you make the promised 500bhp on pump fuel, on Zen rollers!

Shaun

roflol - you tart!

Peanuts

iTrader: (15)

bang to rights Guv'.
slightly o/t but how much of the grunt do you think is head related over say the same set up with standard or mildly opened up heads Shaun?
still amazing result, kudos to you/.

nampahc01

i'll let you no how the re build goes i should hopefully get it built up tomorrow and hopefully get it put back in friday ready to be run in. hope all goes well.

dynamix

iTrader: (3)

Both Shaun and I are running a lot more than girlie boost levels Peanuts on EJ257 blocks There are more doing this than not. There have been very rare instances of bores splitting (2 that I know of).

I cant get my head around why you would buy a forged 2.5 from RCM and not run it to 450 at least.

Mine is built for 650+ and I am still only tickling it at 550.



ps Slowboy was right - you will need a gearbox - the torque will kill it.

Shaun

Peanuts,
I have no idea tbh. I always used to think that opening up and porting heads, will relate to the ability to shift air where air flow is required for higher BHP targets. It would appear that the standard heads can flow more than enough to say surpass 500bhp though.

However, I am led to believe that the heads will provide the same power as standard heads (for a comparative bhp level) but requiring less boost.

Unless you had an identical spec, apart from the heads, it would be difficult to compare.

I would also expect to have a less torquey set-up lowdown if the heads were ported, but that does not seem to be the case with my spec...... quite the opposite infact.

I just pay the money mate!

Peanuts

iTrader: (15)

You know more than you like to let on
You just revel in the banter on 22 Im sure
Its a great help watching people like Shaun and Duncan push the ej257 (both on standard lumps? no relinering?), its a lot to think about with my own forged ej257 just a week or so away from fitting, I'm now looking at pushing for 1.8bar on a 'T' and it should be perky

Do you both also run a twin pump/swirl pot fuel delivery?

dynamix

iTrader: (3)

Mine is linered, I dont think Shaun's block is.

I have a single lift pump in tank and a swirl pot with Bosch 044 doing the last leg to the rails.

Life begins at 2 bar Peanuts

Fai17

iTrader: (2)

you are right Duncan...life really begins at 2 bar.

Fai17

iTrader: (2)

you are right Duncan...life really begins at 2 bar.

dynamix

iTrader: (3)

you can say that again

Shaun

Peanuts,
Boggo standard block casing, with a slight mod. Not re-lined. Standard Spec C in tank as a lift pump, with external 044 Bosch and swirl pot. 1150cc injectors at standard fuel pressure.

Peanuts

iTrader: (15)

Just the one pump Shaun? 044 I mean?

I'd like to know the sizes.
Im going Walbro lift pump to swirl pot on -6
twin -8 from swirl pot to each 044
-6 from each 044 to the rails
-6 return to swirl pot
-6 overflow to tank

Does that sound about right?

What casing mod then Shaun?
cheers for the info guys, its priceless.
Andy

Shaun

Just the one external 044. The duty cycles on the hosepipe injectors are on tick over mode at the moment. The 044 at standard pressure is well adequate for my puny needs.

Not sure why you would need two external 044's with a swirl pot, whilst still retaining a lift pump at this level?

The line sizes sound about right from memory.... no doubt someone else will correct me if I am wrong.

Not supposed to divulge the block mod, sorry. Well, at least I wasn't 18 months ago. lol