Forged engine conversion owners look in...
#1
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Forged engine conversion owners look in...
Im after some info on peoples forged rebuilds/conversions as im in a dilemma and arnt sure what do to when my uk engine lets go. i could do 2.1 - budget big power nice and revvy but id like to keep a lot of torque, so could go 2.5 (althought fully CDB's arnt available?) with a md321 and have a really torquey but not revvy car. OR could meet in the middle, splash on a 2.2 and stroke it to 2.35 and have the best of both worlds?
I want a fast road car thats going to be very capable on handling/drag but i think ultimatly im going to have to have a go in something in the real world!
What capacity did you go for?
Why did you choose the above?
Pros & Cons of your build?
What power does it make?
What do you use the car for?
If you were going to do it again what would you change and why?
Any inputs appreciated.
I want a fast road car thats going to be very capable on handling/drag but i think ultimatly im going to have to have a go in something in the real world!
What capacity did you go for?
Why did you choose the above?
Pros & Cons of your build?
What power does it make?
What do you use the car for?
If you were going to do it again what would you change and why?
Any inputs appreciated.
#2
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Classic or newage?
If its a new age STI then no real problems but then you wouldnt really need to forge the engine if its a classic or new age wrx then its going to get expensive, more torque = new clutch and considerably more strain on the gearbox, on the classic its pretty terminal and you will be forking out for a new one pretty early on (best go for a 6 speed or a PPG conversion, the 6 speed being the stronger and cheaper of the 2 at around 2k) and then the supporting mods (brakes etc) so you will need to take all that into consideration.
Tony
If its a new age STI then no real problems but then you wouldnt really need to forge the engine if its a classic or new age wrx then its going to get expensive, more torque = new clutch and considerably more strain on the gearbox, on the classic its pretty terminal and you will be forking out for a new one pretty early on (best go for a 6 speed or a PPG conversion, the 6 speed being the stronger and cheaper of the 2 at around 2k) and then the supporting mods (brakes etc) so you will need to take all that into consideration.
Tony
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Classic mate. brakes are k sports all round. clutch + gearbox kinda go hand in hand with the engine so its all been taken into consideration just not sure what do do engine wise!
#4
2.5 every time who says they wont rev its an easier as there are more parts available,
we have a 2.5 with the semi closed deck block it hapily makes 570 hp and 509 whp on pump gas with no issues
Theres no substitute for cubic capacity!
we have a 2.5 with the semi closed deck block it hapily makes 570 hp and 509 whp on pump gas with no issues
Theres no substitute for cubic capacity!
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2.5 here too, mine revs just fine also. I worried that it wouldn't be as much fun as a 2 litre, but all that torque is what gives you a smile on your face each time you press the loud pedal.
#6
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Ditto to the above. I was worried about how revvy a 2.5l would be, but a test drive in a 2.5l 485/485 classic soon put paid to any concerns...awesome!
I was going to go the 2.35 route, but the cost of the block put me off. I looked at 2.1, but struggled to understand how a 5% capacity increase could make much difference...readily admit I might be missing the point
So, in the end, a 2.5l made most sense. So far no regrets, but I'm not realising its full potential yet, as I'm still running the stock VF37 twinscroll.
Would I have done anything different? Well, ideally, my 2.0l wouldn't have needed rebuilding in the first place Other than that - no, tbh. Very pleased
I was going to go the 2.35 route, but the cost of the block put me off. I looked at 2.1, but struggled to understand how a 5% capacity increase could make much difference...readily admit I might be missing the point
So, in the end, a 2.5l made most sense. So far no regrets, but I'm not realising its full potential yet, as I'm still running the stock VF37 twinscroll.
Would I have done anything different? Well, ideally, my 2.0l wouldn't have needed rebuilding in the first place Other than that - no, tbh. Very pleased
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Hi Tim, AFAIK the 5% is all in the throw of the crank, so it's all about bottom end torque, making the car pick up sooner and stronger. Plus an easy 8000 rpm safe motor too !
dunx
P.S. I had a 2nd "project" in mind, but the 2.1 was always plan A for next year, or Dec. 2009 before the VAT goes up.
dunx
P.S. I had a 2nd "project" in mind, but the 2.1 was always plan A for next year, or Dec. 2009 before the VAT goes up.
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ive been enjoying my engine tuner built 2.5 the great thing about it is you put your foot down in any gear and you just go like a missile. 2.3 is amazing but only worth doing if your getting head work done and you got deep pockets for some after makert heads and to be honest 2.3 with lunpy idel might be great for the track etc but on the road a 2.5 wins it for all the time its just so effortless to drive. you really got to drive one to for a few hours to know what im talking about. and btw a 2.5 would rev providing you got the right turbo and set just ask shaun with the mad spec c he will tell you 2bar of boost at 3k.
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i think daves is a 2.0 re-linered - heard liners can slip though? thats the only thing that puts me off?
i think with the right heads/cams, pulleys, flywheel and turbo i could be onto a winner with a 2.5
yea im gonna have to have a go in one i think - anyone wana take me for a spin? lol
i think with the right heads/cams, pulleys, flywheel and turbo i could be onto a winner with a 2.5
yea im gonna have to have a go in one i think - anyone wana take me for a spin? lol
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lol, sorry I mean't the guy building the engine has told him his won't slip....maybe a design reason they don't slip?
I remember reading on the american forum, they now use liners which have some sort of 'lip' so cannot slip.
I remember reading on the american forum, they now use liners which have some sort of 'lip' so cannot slip.
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tell me about it. got rid of the sti5 heads for some sexy new ones. bloody expensive with the new cams. twill need shimmed up as well
Last edited by bigsinky; 18 September 2009 at 05:51 PM.
#24
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I'm hoping to show that an EJ257 with cheap and simple strengthening will cope with circa 600bhp no problem.
Wrighty I'd honestly say to go for an EJ257 with rods and pistons. an MD321V on it would make a lovely car.
My previous 2.5 with a rotated GT30R was a dream to drive. sensible and civilised round the town and then out in the **** end of nowhere it was awesome!!
Standard STI5 heads will also cope very nicely with 500bhp.
Wrighty I'd honestly say to go for an EJ257 with rods and pistons. an MD321V on it would make a lovely car.
My previous 2.5 with a rotated GT30R was a dream to drive. sensible and civilised round the town and then out in the **** end of nowhere it was awesome!!
Standard STI5 heads will also cope very nicely with 500bhp.
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What are the weaknesses of a EJ257? I presume they're ODB?
Edit: as in if all the other components are mint, like pistons etc, would the block actually fail?
Edit: as in if all the other components are mint, like pistons etc, would the block actually fail?
Last edited by chrisdicko; 18 September 2009 at 08:07 PM.
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I'm hoping to show that an EJ257 with cheap and simple strengthening will cope with circa 600bhp no problem.
Wrighty I'd honestly say to go for an EJ257 with rods and pistons. an MD321V on it would make a lovely car.
My previous 2.5 with a rotated GT30R was a dream to drive. sensible and civilised round the town and then out in the **** end of nowhere it was awesome!!
Standard STI5 heads will also cope very nicely with 500bhp.
Wrighty I'd honestly say to go for an EJ257 with rods and pistons. an MD321V on it would make a lovely car.
My previous 2.5 with a rotated GT30R was a dream to drive. sensible and civilised round the town and then out in the **** end of nowhere it was awesome!!
Standard STI5 heads will also cope very nicely with 500bhp.
howd your 2.5 go through corners etc, did it pick up ok through tight twisties?
or can anyone else answer that?
#29
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Personally I wouldn't waste a decent CDB by attempting to liner it.