Starting again.... with a Hawkeye
09 May 2012, 07:00 PM
#842
Great write up Shaun. I spent most of the bank holiday reading the whole article.
After you putting on the LM450 and getting around 400hp with the standard i/c and air box it's a shame you could not have found out which one(if not both) were causing the restriction in power. It would have been of good help to have had the comparative test results. Especially as there were divided opinions on the subject by the likes of DavidAPI and Andy F.
I'm thinking of going similar route and by-passing the LM400 and 420 and go straight for the 450 billet. Question: would it be safe to run a 'restricted' LM450 with standard air box and v.8 STI I/C ? If mapped properly what would be the draw backs?
Cheers
Andrew
After you putting on the LM450 and getting around 400hp with the standard i/c and air box it's a shame you could not have found out which one(if not both) were causing the restriction in power. It would have been of good help to have had the comparative test results. Especially as there were divided opinions on the subject by the likes of DavidAPI and Andy F.
I'm thinking of going similar route and by-passing the LM400 and 420 and go straight for the 450 billet. Question: would it be safe to run a 'restricted' LM450 with standard air box and v.8 STI I/C ? If mapped properly what would be the draw backs?
Cheers
Andrew
Last edited by apac; 09 May 2012 at 07:06 PM.
12 May 2012, 07:51 PM
#843
Scooby Regular
Thread Starter
Great write up Shaun. I spent most of the bank holiday reading the whole article.
After you putting on the LM450 and getting around 400hp with the standard i/c and air box it's a shame you could not have found out which one(if not both) were causing the restriction in power. It would have been of good help to have had the comparative test results. Especially as there were divided opinions on the subject by the likes of DavidAPI and Andy F.
I'm thinking of going similar route and by-passing the LM400 and 420 and go straight for the 450 billet. Question: would it be safe to run a 'restricted' LM450 with standard air box and v.8 STI I/C ? If mapped properly what would be the draw backs?
Cheers
Andrew
After you putting on the LM450 and getting around 400hp with the standard i/c and air box it's a shame you could not have found out which one(if not both) were causing the restriction in power. It would have been of good help to have had the comparative test results. Especially as there were divided opinions on the subject by the likes of DavidAPI and Andy F.
I'm thinking of going similar route and by-passing the LM400 and 420 and go straight for the 450 billet. Question: would it be safe to run a 'restricted' LM450 with standard air box and v.8 STI I/C ? If mapped properly what would be the draw backs?
Cheers
Andrew
I know you can get higher figures with the OEM TMIC, so I really do expect that a change of inlet would have allowed greater power potential..... however, with the OEM TMIC there are caveats with that, as you start to run the risk of det in warmer weather and sustained throttle. Not really a way forward for a road car imo.
100% fine running that spec on a LM450. It just means that you won't get the potential of the peak power the turbo can achieve. You're basically reducing airflow, but this will not cause you any issues in reality afaik.
Good luck!
19 May 2012, 04:12 PM
#844
Scooby Regular
Thread Starter
It's been nearly 6 whole months since the last performance modification...... it's time for the next. Meth is too strong to resist and my curiosity is getting the better of me.
Watch this space!
Could I be another fuel additive convert and will my OEM clutch tell me to fist myself!?
Guess we'll find out.
Watch this space!
Could I be another fuel additive convert and will my OEM clutch tell me to fist myself!?
Guess we'll find out.
19 May 2012, 06:02 PM
#847
Scooby Regular
Thread Starter
19 May 2012, 06:06 PM
#848
Scooby Regular
Thread Starter
20 May 2012, 08:16 AM
#853
Scooby Regular
Hi All,Recently a piston gave up on my 2003 twinscroll impreza sti jdm and now i decided to beef up the engine.What is the biggest power Twinscroll stock location Turbo(that still mates to my tomei headers and milltek downpipe) currently on the market and if more than 1 what are the options?.Im looking to use the car for road use where drivability is important,drag use and track,Besides the most important thing now is not the turbo but the engine build.I know that maybe this topic has been covered times before but i havent found any much details.Im considering a 2.1 stroker kit(Using my existing ej20 semi closed block) or go the 2.5 route(which the only extra cost is the block circa 1000 pounds(semi closed with 14mm stud conversion) and little machining on the chamber of the heads).But im confused on what is the 'best' to go with,As some say the 2.1 is better for track than a 2.5 due to 'revs',I also heard that the 2.5 is less reliable and has an appetite for head gasket,maybe due to the semi closed deck not good enough for a high power 2.5.I have been told that 500bhp is the most safe from a 2.5(semi closed).I have never tried a 2.5 before but i've seen one with a gt35 and it spools that turbo like crazy,almost even better than my 2.0 with the vf37.Im looking for an engine that will be the 'most' reliable with the biggest twinscroll stock location turbo.What do you think guys?thanks a lot
20 May 2012, 01:39 PM
#854
Litchfield offer the twin-entry LM500, easily good enough for 500 bhp (I get 490bhp on a 2.5 from their LM480 on Vpower) and there's the Scoobyclinic SC50 twinscroll but I don't think I've seen results from that yet.
For me, there are two different things to consider here: engine capacity and twin vs single scroll.
My 2.5, built with 11mm ARPs, blew its head gaskets after 30,000 road miles and about 3 track days - it was a track day that did it. It is now rebuilt with 14mm ARPs and I expect it to last a while, but I also expect - plan, even - for something to go wrong at some point.
The main issue with 2.5's is that the liners expand/move, which breaks the h/g seals - 14mm ARPs really help with that, meaning the next issue to worry about liners ballooning. This can be mitigated against by keeping boost down (1.6-1.7 bar max - mine is mapped for 1.65bar, but I see 1.8bar peaks on occasion) or by pinning the block (expensive, not that many pinned 2.5s out there, but sounds good).
Received wisdom is to keep a standard 2.5 block below 500bhp/500ftlb - and some builders will lower that to 450 of each based on their experience of (standard) 2.5 blocks.
A 2.1 based on a CDB is probably the best value build you can do. Second best, IMHO, would be a 2.1 based on your 2.0 SCDB - with hindsight that's what I would have done had 2.1's been better known about when I first had my 2.5 built after the 2.0 JDM SCDM STi engine failure 4 years ago.
Money no object: a 2.35 based on an EJ22T CDB block. The block will set you back about £1200 and then there's the machining. Not cheap, but bl**dy good
Then the twin vs single scroll argument. There are MANY well proven single scroll turbos out there with excellent spool and power characteristics. I have no doubt that the 400-450bhp twin scroll or twin entry turbos (LM450, SC46 TS for example) make for an easy upgrade for twinscroll owners, but...
...for a 500bhp build it is, I believe, more of a compromise. Yes, my LM480 gives good power, but I have always felt the spool is poor for a 2.5. Is that my heads (shouldn't be - they're cleaned-up JDM 2.0 "big port" items)? My overall build? I'll probably never know. Bob Rawle has an LM500 on a pegged 2.5, pushing out over 500bhp, and his spools about 300-400rpm better than mine - but he has wilder cams and Cosworth heads, so no real comparison.
I would do a search on 500bhp engines - 2.0, 2.1 and 2.5 depending on what you fancy - and have a good close look at the spool characteristics. You may find that it is better to sell on your VF37, exhaust manifold and milltek downpipe, and convert to single scroll. It will not cost you any more and may just give you better results. I've not done that myself, so please do the research and report back
That said, I do know there is a possible new entrant to the twinscroll 500bhp market hopefully about to prove itself...so you may want to keep a look out for any posts by John Felstead
Final words: make sure you have deep pockets as 500bhp engines do not come cheap. By the time I'd bought the FMIC, injectors, turbo, uprated clutch, mapping sessions etc - and the 2.5 build itself - I'd spent about £15k. Then came the Syvecs since the MAF-based EcuTek tune was on its limit, IMHO, plus the costs when the head gaskets went...and so it goes on.
Oh well, you can only spend it once 
For me, there are two different things to consider here: engine capacity and twin vs single scroll.
My 2.5, built with 11mm ARPs, blew its head gaskets after 30,000 road miles and about 3 track days - it was a track day that did it. It is now rebuilt with 14mm ARPs and I expect it to last a while, but I also expect - plan, even - for something to go wrong at some point.
The main issue with 2.5's is that the liners expand/move, which breaks the h/g seals - 14mm ARPs really help with that, meaning the next issue to worry about liners ballooning. This can be mitigated against by keeping boost down (1.6-1.7 bar max - mine is mapped for 1.65bar, but I see 1.8bar peaks on occasion) or by pinning the block (expensive, not that many pinned 2.5s out there, but sounds good).
Received wisdom is to keep a standard 2.5 block below 500bhp/500ftlb - and some builders will lower that to 450 of each based on their experience of (standard) 2.5 blocks.
A 2.1 based on a CDB is probably the best value build you can do. Second best, IMHO, would be a 2.1 based on your 2.0 SCDB - with hindsight that's what I would have done had 2.1's been better known about when I first had my 2.5 built after the 2.0 JDM SCDM STi engine failure 4 years ago.
Money no object: a 2.35 based on an EJ22T CDB block. The block will set you back about £1200 and then there's the machining. Not cheap, but bl**dy good
Then the twin vs single scroll argument. There are MANY well proven single scroll turbos out there with excellent spool and power characteristics. I have no doubt that the 400-450bhp twin scroll or twin entry turbos (LM450, SC46 TS for example) make for an easy upgrade for twinscroll owners, but...
...for a 500bhp build it is, I believe, more of a compromise. Yes, my LM480 gives good power, but I have always felt the spool is poor for a 2.5. Is that my heads (shouldn't be - they're cleaned-up JDM 2.0 "big port" items)? My overall build? I'll probably never know. Bob Rawle has an LM500 on a pegged 2.5, pushing out over 500bhp, and his spools about 300-400rpm better than mine - but he has wilder cams and Cosworth heads, so no real comparison.
I would do a search on 500bhp engines - 2.0, 2.1 and 2.5 depending on what you fancy - and have a good close look at the spool characteristics. You may find that it is better to sell on your VF37, exhaust manifold and milltek downpipe, and convert to single scroll. It will not cost you any more and may just give you better results. I've not done that myself, so please do the research and report back
That said, I do know there is a possible new entrant to the twinscroll 500bhp market hopefully about to prove itself...so you may want to keep a look out for any posts by John Felstead
Final words: make sure you have deep pockets as 500bhp engines do not come cheap. By the time I'd bought the FMIC, injectors, turbo, uprated clutch, mapping sessions etc - and the 2.5 build itself - I'd spent about £15k. Then came the Syvecs since the MAF-based EcuTek tune was on its limit, IMHO, plus the costs when the head gaskets went...and so it goes on.
Oh well, you can only spend it once
20 May 2012, 04:06 PM
#855
Scooby Regular
Thanks for that post Tim it had much of the information i was looking for.So in other words you're saying that its better to stick to a 2.1 then to go to the 2.5 route.That said what is the biggest Turbo (Litchfield one's) on a 2.1 you think will have almost the same spool as a stock 2ltr jdm engine with an lm450?As i think that an lm500 is "laggy" on a 2.1 considering your's on a 2.5 find the lm480 "laggy",But I still guess that a 2.1 with an lm450 and the other a 2.5 with an lm500 the 2.5 will have an edge on the 2.1 in all circumstances besides maybe 'reliability'.Has anyone ever compared an lm500 billet with a MD321V billet?thanks alot
21 May 2012, 12:37 PM
#860
Scooby Regular
Thread Starter
Alyn,
IMO the only issue with that method or pinning, is the long term reliability.... I'm not sure enough data is out there to prove anything either way.
Cliff,
Do what you want.
Harvey,
You are of course correct!
22 May 2012, 09:32 AM
#861
Hi guys! Just installed the Hybrid fmic. As for me the view it looks installed is not perfect. Serviceman says it's better to keep the upper bumper molding, that covers 1/3 of the fmic, for a better look, but will it affect the perfomance? There is a gap about 4cm between that black plastic line and a fmic core, so the air cold pass in.
What is your opinion, to cut that plastic away or keep everything as is?
Thinking about the perfect look, I am planning to change the core to Perrin one. May be even black color core, that Perrins fit MY03 bumper most perfectly. Here it is:
What is your opinion, just perfomance wise, to cut a black plastic line, or to keep as is? Would be a noticable difference in the air amount that goes thru the fmic core?
What is your opinion, to cut that plastic away or keep everything as is?
Thinking about the perfect look, I am planning to change the core to Perrin one. May be even black color core, that Perrins fit MY03 bumper most perfectly. Here it is:
What is your opinion, just perfomance wise, to cut a black plastic line, or to keep as is? Would be a noticable difference in the air amount that goes thru the fmic core?
22 May 2012, 09:45 AM
#862
Scooby Regular
Thread Starter
The more direct unobstructed airflow can only help, however I have installed mine as yours.... it's fine as in reality air gets thrown around the whole area when you're moving. I wouldn't worry about it.
With regards to fitting a Perrin core.... if the look is that important to you that's your choice.... personally I think you're mad in doing that just for the look, over a GT2 core from the Hybrid.
With regards to fitting a Perrin core.... if the look is that important to you that's your choice.... personally I think you're mad in doing that just for the look, over a GT2 core from the Hybrid.
23 May 2012, 11:01 AM
#863
The look and perfomance are related here, Perrin allows to get more direct air and perfoms better, it comes with the support bar (Hybrid does not!). I'll wait what my mapper will say, if the intake temp will be ok, so no worries. Any opinions about the partly covered fmic, guys? Any mappers here?
25 May 2012, 10:11 AM
#865
Better fitment means better perfomance here. Why the Hybrid did this design of the core, which does not fit 2001, 2003, and 2005+ bumpers perfectly, sidetanks are seen and large windows there and there? Seems they did a job for GC8 much better!
The main quastion for me is how long the engine will last with 450bhp.. What is the weakest point in the stock EJ207 engine? Rods? Head gasket and studs? crank bearings? I don't want to open the engine now, as many of my friends advice me here to get all the "forged" stuff inside. Let's see how long it will live
The main quastion for me is how long the engine will last with 450bhp.. What is the weakest point in the stock EJ207 engine? Rods? Head gasket and studs? crank bearings? I don't want to open the engine now, as many of my friends advice me here to get all the "forged" stuff inside. Let's see how long it will live
25 May 2012, 12:16 PM
#866
Scooby Regular
Thread Starter
Better fitment means better performance? Not sure that's justified imo! Sure.... the kit may not look "as nice" as a Perrin, but when you consider the price difference, is it really an issue. Horses for courses and all that.... common sense prevails for most.
Your engine will last as long as nothing goes wrong! Not sure anyone can add anymore than that in reality. I've known of these engines to pop at 420bhp and take well over 500bhp. Personally I would not want to push much more than 450bhp from the standard unit..... but that's my opinion.
I'd suspect the map(per), rods and pistons are your weak points.
Your engine will last as long as nothing goes wrong! Not sure anyone can add anymore than that in reality. I've known of these engines to pop at 420bhp and take well over 500bhp. Personally I would not want to push much more than 450bhp from the standard unit..... but that's my opinion.
I'd suspect the map(per), rods and pistons are your weak points.
25 May 2012, 08:48 PM
#867
Former Sponsor
The best twin scroll turbo I have come across is the Litchfield LM500 billet, I am biased but my own car made 552 bhp at 1.55 bar and 550 ft lbs torque at 1.65 bar on V Power ... no meth anywhere near, so the turbo is well able to supply enough air, then its all down to the engine spec and supporting mods.
The best twin scroll headers are the std oem ones, those Tomei headers are no where near as good.
I was looking at a SC50 turbo a couple of days ago and the exhaust (turbine) housing looks to be going to possibly act as a restriction, but it needs some definitive bench marking of course.
Whilst the LM series are actually twin entry they all do what is on the tin as a minimum, I have not found one that does not exceed its quota when fitted to a complimentary spec set up.
having mapped 2.1 and 2.5 cars with it installed its really not that much more laggy on a 2.1 and is much better than most other turbo's.
The MD321V billet single entry would not get to my 552 figures on V Power at the same boost.
cheers
bob
The best twin scroll headers are the std oem ones, those Tomei headers are no where near as good.
I was looking at a SC50 turbo a couple of days ago and the exhaust (turbine) housing looks to be going to possibly act as a restriction, but it needs some definitive bench marking of course.
Whilst the LM series are actually twin entry they all do what is on the tin as a minimum, I have not found one that does not exceed its quota when fitted to a complimentary spec set up.
having mapped 2.1 and 2.5 cars with it installed its really not that much more laggy on a 2.1 and is much better than most other turbo's.
The MD321V billet single entry would not get to my 552 figures on V Power at the same boost.
cheers
bob
26 May 2012, 08:19 AM
#868
Scooby Regular
Thread Starter
Bob,
Your comparison to the "V" is interesting.... your results on your build are certainly awesome with the LM500.
So when you trying the Meth mix then.... out of development curiosity of course.
I would think the LM450 on a 2.1ltr would be absolute bliss and a marriage made in heaven.
Your comparison to the "V" is interesting.... your results on your build are certainly awesome with the LM500.
So when you trying the Meth mix then.... out of development curiosity of course.
I would think the LM450 on a 2.1ltr would be absolute bliss and a marriage made in heaven.
04 June 2012, 06:29 AM
#869
Hi guys! My engine seems more dead than alive now After many work with the car, installing the fmic, intake, exhaust, etc.. at the very last moment, when serviceman started the engine to go out of the service area (car was there for 2 months).. the oil pressure lights flashed!! DEFIs showed 0 pressure and 0 temp. We checked everything, it seems it's a oilpump failure. There is some valve that drops an excessive pressure, they say it is a common issue on subarus ! ) Oil level was full.
What is sad we found some aluminium sand in the drained oil. Engine was running for 1-2 minutes without the oil, turbotimer did it's job. I was not there at that moment so could not help. The servicemen didn't know how to stop the engine.
It seems that crank bearings are worn, today they are opening the engine
I have a choice now, to put it a 2.135cc stroker, to buy the 2.0 forged kit, or to keep the OE internals and change just the crank bearings worned.
My mechanic hates these strokers, he says the piston's skirt is short there so he strongly recommends me to keep 2.0 engine size. I want any negative facts about 2.1 strokers from users who running on them.
What is your opinion, guys? I found Brian Crower and Mahle 2.135 stroker here in stock, not to listen the mech and just get it or somebody here have an another opinion on 2.1 strokers? My turbo is MD321T 450+bhp, what is the perfect setup for this turbo?
I have to choose wich way to go, have to think fast, in ten days the mapper will be here, I am waiting him for a very long time, so the car must be ready in 10 days.
Is OE piston/rod setup is that good for 450-500bhp to keep them? Here is opinion that it's better than some aftermarket forged crap with huge thermal gaps.
The money is not a quastion here, my goal is to make an investment into future engine life, the internals must be strong for 500bhp at least.
Any advices appreciated, guys.
After many work with the car, installing the fmic, intake, exhaust, etc.. at the very last moment, when serviceman started the engine to go out of the service area (car was there for 2 months).. the oil pressure lights flashed!! DEFIs showed 0 pressure and 0 temp. We checked everything, it seems it's a oilpump failure. There is some valve that drops an excessive pressure, they say it is a common issue on subarus ! ) Oil level was full.What is sad we found some aluminium sand in the drained oil. Engine was running for 1-2 minutes without the oil, turbotimer did it's job. I was not there at that moment so could not help. The servicemen didn't know how to stop the engine.
It seems that crank bearings are worn, today they are opening the engine
I have a choice now, to put it a 2.135cc stroker, to buy the 2.0 forged kit, or to keep the OE internals and change just the crank bearings worned.
My mechanic hates these strokers, he says the piston's skirt is short there so he strongly recommends me to keep 2.0 engine size. I want any negative facts about 2.1 strokers from users who running on them.
What is your opinion, guys? I found Brian Crower and Mahle 2.135 stroker here in stock, not to listen the mech and just get it or somebody here have an another opinion on 2.1 strokers? My turbo is MD321T 450+bhp, what is the perfect setup for this turbo?
I have to choose wich way to go, have to think fast, in ten days the mapper will be here, I am waiting him for a very long time, so the car must be ready in 10 days.
Is OE piston/rod setup is that good for 450-500bhp to keep them? Here is opinion that it's better than some aftermarket forged crap with huge thermal gaps.
The money is not a quastion here, my goal is to make an investment into future engine life, the internals must be strong for 500bhp at least.
Any advices appreciated, guys.
Last edited by Semion; 04 June 2012 at 09:26 AM.
04 June 2012, 12:58 PM
#870
If you want 500BHP then you should really look at aftermarket pistons/rods.
I'm using a 2.1 with custom 2618 Mahle pistons and manley rods, seems to work OK for me. A 2.1 should work well with that turbo. 2618 mahle does run larger clearances, so there is some extra noise at idle, but you soon get used to that and you dont hear it when driving. my kit is not the same as the off the shelf mahle kit, so can't say what that is like.
You will have to change your crank whatever you do, the current one will be knackered.
I'm using a 2.1 with custom 2618 Mahle pistons and manley rods, seems to work OK for me. A 2.1 should work well with that turbo. 2618 mahle does run larger clearances, so there is some extra noise at idle, but you soon get used to that and you dont hear it when driving. my kit is not the same as the off the shelf mahle kit, so can't say what that is like.
You will have to change your crank whatever you do, the current one will be knackered.