engine build time 2.5 liter or 2.0 liter
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engine build time 2.5 liter or 2.0 liter
Right the time has come, The engine in my version 4 wrx is tired and i want more power so new engine required (450+ bhp more in the future lol) and i would like to over enginer it to be honest because there is no point in doing it twice lol .. BUT where to start which engine is a better choice idea/stronger (can't make my mind up lol as i work with impreza's all day long and every one has there own opinion to impose on me lol maybe this is the wrong idea to post on here but i need some answers and 2.5LTR's weak or not)
i am looking to build either a
2.5 semi-closed desck block with a nitrated crank, ACL race bearings, forged rods (eagle any other recomended), forged pistons (CP/mahle), 14mm headstud conversion, cometic head gaskets (not to sure on size yet), 12mm uprated oil pump, with a set of STI 3/4 heads bolted to it (most likely ported/polished)
OR
2.0 semi closed deck block (or closed deck) with a nitrated cross driled v9 cranck, ACL race bearings, forged rods (eagle any other recomended), forged pistons (mahle), 14mm headstud conversion, cometic head gaskets (not to sure on size yet), 12mm uprated oil pump, with a set of STI 3/4 heads bolted to it (most likely ported/polished)
All ready got 6 speed sorted with complete r180 rear end with brembo's all round, coilovers, ARB's, so power can be handled. Also very large front mount fitted
HMMMM what turbo to used aswell was thinking a md321T not going twisted set-up yet lol
thanks scott
i am looking to build either a
2.5 semi-closed desck block with a nitrated crank, ACL race bearings, forged rods (eagle any other recomended), forged pistons (CP/mahle), 14mm headstud conversion, cometic head gaskets (not to sure on size yet), 12mm uprated oil pump, with a set of STI 3/4 heads bolted to it (most likely ported/polished)
OR
2.0 semi closed deck block (or closed deck) with a nitrated cross driled v9 cranck, ACL race bearings, forged rods (eagle any other recomended), forged pistons (mahle), 14mm headstud conversion, cometic head gaskets (not to sure on size yet), 12mm uprated oil pump, with a set of STI 3/4 heads bolted to it (most likely ported/polished)
All ready got 6 speed sorted with complete r180 rear end with brembo's all round, coilovers, ARB's, so power can be handled. Also very large front mount fitted
HMMMM what turbo to used aswell was thinking a md321T not going twisted set-up yet lol
thanks scott
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hows tricks bud? ive had a few now but the spec c is my 1st twin scroll and im well happy with it apart from the turbo seems to run out of legs in 5/6th so maybe a bigger turbo and injectors nxt
so what sort of power are you looking for?
so what sort of power are you looking for?
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If you work for Andy why arnt you asking him ??
2.5 is good for torque and can be reliable if built properly, I'd be pegging the liners if your doing the job right
Eagle rods well for get that they arnt good to be honest, go for something like manley/carrillo/cosworth
Mahle Pistons are spot on, theres a couple of choices though High/low silicon content.
sti v4 heads would be better on the 2.5 but get them machined to suit.
2.5 is good for torque and can be reliable if built properly, I'd be pegging the liners if your doing the job right
Eagle rods well for get that they arnt good to be honest, go for something like manley/carrillo/cosworth
Mahle Pistons are spot on, theres a couple of choices though High/low silicon content.
sti v4 heads would be better on the 2.5 but get them machined to suit.
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If you work for Andy why arnt you asking him ??
2.5 is good for torque and can be reliable if built properly, I'd be pegging the liners if your doing the job right
Eagle rods well for get that they arnt good to be honest, go for something like manley/carrillo/cosworth
Mahle Pistons are spot on, theres a couple of choices though High/low silicon content.
sti v4 heads would be better on the 2.5 but get them machined to suit.
2.5 is good for torque and can be reliable if built properly, I'd be pegging the liners if your doing the job right
Eagle rods well for get that they arnt good to be honest, go for something like manley/carrillo/cosworth
Mahle Pistons are spot on, theres a couple of choices though High/low silicon content.
sti v4 heads would be better on the 2.5 but get them machined to suit.
for starters i have asked andy obviouse, that is the first choice looking for other opinions/ideas as it is something i only want to do once lol
going for manley rods just been doing more research lol, forged eagle wondered why the were so cheep lol,
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these 2.1's are very popular looking for lots of torque not going over 500bhp to be honest as it become's unusable on the road in my opinion forgot to mension want a reliable road car in post not asking for much lol haha maybe have to stick to 450 lol
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Hey Scott, have you not spoke with Brian?
I believe the 2.1 is a great choice for a quick road car with track day useablitiy. It proabably bar the standard 2.0 forged the cheapest option out of the options available too. Some name that spring to mind, Pennie & EngineTuner that are relatively local.
As for the Turbo I assume your going standard plumbing? MD321, SC46, GT30, Some of the VF Ranges...
https://www.scoobynet.com/scoobynet-...t=400bhp+worth
Rob
I believe the 2.1 is a great choice for a quick road car with track day useablitiy. It proabably bar the standard 2.0 forged the cheapest option out of the options available too. Some name that spring to mind, Pennie & EngineTuner that are relatively local.
As for the Turbo I assume your going standard plumbing? MD321, SC46, GT30, Some of the VF Ranges...
https://www.scoobynet.com/scoobynet-...t=400bhp+worth
Rob
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[QUOTE=Scott@ScoobySpares;9931333]Right the time has come, The engine in my version 4 wrx is tired and i want more power so new engine required (450+ bhp more in the future lol) and i would like to over enginer it to be honest because there is no point in doing it twice
2.35 may be expensive but still cheaper than doing it twice or more.
2.35 may be expensive but still cheaper than doing it twice or more.
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wow 2.1's are being pushed lol wasn't too sure about them but sound good, always thought 2.5 better due to enine size lol but i have read up a bit on them now and i am impressed,
got a quick option on the cards i have been offered a 2.5sti short motor with forged RCM pistons sti 9 rods/crank (£1100) what is this good for power wise without pushing it too far what turbo to fit???
got a quick option on the cards i have been offered a 2.5sti short motor with forged RCM pistons sti 9 rods/crank (£1100) what is this good for power wise without pushing it too far what turbo to fit???
Last edited by Scott@ScoobySpares; 13 March 2011 at 12:28 AM.
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2.5's I believe (stand to be corrected) are bloody good every day road cars, loads of torque and good for around 400bhp ish, past this point and it becomes dangerous, they are prone to bottom end failure (correct me if im wrong guys). The 2.5 rebuild from RCM needs to be put to RCM for answers imho. As for the choice in turbos, there is a good thread on here, i'll just have a quick search and get back....
Edit - Here you buddy.... https://www.scoobynet.com/general-te...ighlight=md321
Rob
Edit - Here you buddy.... https://www.scoobynet.com/general-te...ighlight=md321
Rob
Last edited by Rob Day; 13 March 2011 at 12:32 AM.
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2.5's I believe (stand to be corrected) are bloody good every day road cars, loads of torque and good for around 400bhp ish, past this point and it becomes dangerous, they are prone to bottom end failure (correct me if im wrong guys). The 2.5 rebuild from RCM needs to be put to RCM for answers imho. As for the choice in turbos, there is a good thread on here, i'll just have a quick search and get back....
Edit - Here you buddy.... https://www.scoobynet.com/general-te...ighlight=md321
Rob
Edit - Here you buddy.... https://www.scoobynet.com/general-te...ighlight=md321
Rob
not too sure if it has been built by RCM don't think it has they have supplied the pistons, i know the person selling it well and all his stuff is good, also know the mapper who mapped this engine in the last car it was in and heard good reports
nice to hear that they are good road engines 2.5s don't want to track as i would rather build another car on a budget for track more fun as tracking something you have a lot of money has its worries lol if it blew it blew lol
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Thanks rob read this thread hmmm help full
not too sure if it has been built by RCM don't think it has they have supplied the pistons, i know the person selling it well and all his stuff is good, also know the mapper who mapped this engine in the last car it was in and heard good reports
nice to hear that they are good road engines 2.5s don't want to track as i would rather build another car on a budget for track more fun as tracking something you have a lot of money has its worries lol if it blew it blew lol
not too sure if it has been built by RCM don't think it has they have supplied the pistons, i know the person selling it well and all his stuff is good, also know the mapper who mapped this engine in the last car it was in and heard good reports
nice to hear that they are good road engines 2.5s don't want to track as i would rather build another car on a budget for track more fun as tracking something you have a lot of money has its worries lol if it blew it blew lol
I have since ran the last 2k on a 35R which made circa 620bhp on sunaco 109 @ 1.65Barg held. Its also done some drag events in this guise. Its been reved to 8.5K at these events with out issue.
It gets used and abused and runs fine. It also revs as quick as many ej20 I have mapped, which seems to be another myth about the 2.5
There's no reason why a properly built ej257 with good quality supporting mods should not be as reliable as any other low capacity engine running at these power levels.
Cheers
Col
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Thanks rob read this thread hmmm help full
not too sure if it has been built by RCM don't think it has they have supplied the pistons, i know the person selling it well and all his stuff is good, also know the mapper who mapped this engine in the last car it was in and heard good reports
nice to hear that they are good road engines 2.5s don't want to track as i would rather build another car on a budget for track more fun as tracking something you have a lot of money has its worries lol if it blew it blew lol
not too sure if it has been built by RCM don't think it has they have supplied the pistons, i know the person selling it well and all his stuff is good, also know the mapper who mapped this engine in the last car it was in and heard good reports
nice to hear that they are good road engines 2.5s don't want to track as i would rather build another car on a budget for track more fun as tracking something you have a lot of money has its worries lol if it blew it blew lol
Off Topic - Andrew will be mapping mine Early next week, my car is at his unit where Brain is undertaking the pre-map work
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There's an awful lot of rubbish being said about the 2.5's here.
All this crap about them being sluggish and not reving well is utter bollocks.
Built right with the right components and they will be very very responsive and rev to 8K without issue!!
Their only shortcoming is block integrity at above 500bhp which can be tackled by pins around the bores.
600bhp and 585ft lbs from mine mine's just been stripped due to dropped valve and the bores are mint. It will soon see close to 650 - 700bhp I then hope to dispell any myths about the 2.5.
Here's a graph from my latest dyno run this is with standard heans and cams too.
All this crap about them being sluggish and not reving well is utter bollocks.
Built right with the right components and they will be very very responsive and rev to 8K without issue!!
Their only shortcoming is block integrity at above 500bhp which can be tackled by pins around the bores.
600bhp and 585ft lbs from mine mine's just been stripped due to dropped valve and the bores are mint. It will soon see close to 650 - 700bhp I then hope to dispell any myths about the 2.5.
Here's a graph from my latest dyno run this is with standard heans and cams too.
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Dazdavies - Am I right regarding the standard 2.5 bottom end being potentially unstable past 400bhp or thereabouts? I was considering this when I bought my last project car, and looked into putting a 2.5 STI Forrester engine in my 2002 STI, but was informed that 400bhp would be the limit, and even this would be pushing my luck?!?!? Obviously with the right aftermarket components its possible to push more, but then even the block in OEM form can be at risk beyond 500bhp?
Sorry for sounding thick, but when you believe all you read without having the knowledge or experience like yourself its all 'here-say'. Your motor is/was certainly proof in the pudding, and my dearest compliments to you.
It was a shame the last SSO was soaking as I would have like to have seen some better times, although despite the monsoon it was amazing to see the times you and many other were managing to plant down the 1/4.
Rob
PS, Scott - Im sure Dunx missed your info from the original thread, and yes im again 'under the impression' that a standard 6 speed box if not abused will take upto 550bhp, and maybe more.... I think I read someone pushing 603bhp.... Banny is running well over 500bhp on his 6 speed which is also a 2.0 STI lump if memory serves me correct?
Rob
Sorry for sounding thick, but when you believe all you read without having the knowledge or experience like yourself its all 'here-say'. Your motor is/was certainly proof in the pudding, and my dearest compliments to you.
It was a shame the last SSO was soaking as I would have like to have seen some better times, although despite the monsoon it was amazing to see the times you and many other were managing to plant down the 1/4.
Rob
PS, Scott - Im sure Dunx missed your info from the original thread, and yes im again 'under the impression' that a standard 6 speed box if not abused will take upto 550bhp, and maybe more.... I think I read someone pushing 603bhp.... Banny is running well over 500bhp on his 6 speed which is also a 2.0 STI lump if memory serves me correct?
Rob