2.5l conversion or 2.0l rebuild/replacement?

06 May 2008, 19:05

OK, so I think I've found out what the tapping noise is coming from the engine. I think it's coming from the crank shaft bearings.

What would be the best option.
1. Replace the engine with a 2.0l recon unit at about £800.
2. Repair the current engine and rebuild with forged pistons/con rods. +/- £800??
3. Replace with a 2.5l short block for £1500 (or $1800 US + shipping). But I'm not sure what else will need to be done for the rebuild. Mapping, injectors etc.

Your advice will be much appreciated.

Thanks.

06 May 2008, 19:37

If you can afford it then certainly go for the 2.5l conversion, you won't need anything more than what you would need on the normal build, but would say a remap is required once fitted.

If your bottom end is gone then chances are you need a new crank, so would make option 2 just as expensive as option 3.

06 May 2008, 23:05

I'd like to hear from anyone that has bought a recon 2.0l engine or a 2.5l shortblock??

Someone must have gone down either of these routes recently.

Please help!!

07 May 2008, 01:42

fit 2.5 ......you will not regret it ....makes the car soooo much better to drive (instant power ), you can either leave it stock or have a forge built 2.5 for 500+ bhp

mine you you will use more fuel though and insurane will go up as well !
but then we do not drive these type of cars for fuel economy

07 May 2008, 10:05

depends on whether you are after a revvy engine(2.0) or a tourquey engine(2.5), personally 2.5 would be the better way to go, more widespread power and tons of tourque.

If you do go for the 2.5 make sure you uprate the gearbox, im risking it with a standard 2.0 5spd box so ieally go for a sti 6 spd or a ppg 5 speed if you can handle the whining from the box.

Jay

07 May 2008, 10:16

Quote:

Originally Posted by impreza_terzo3_no257

depends on whether you are after a revvy engine(2.0) or a tourquey engine(2.5), personally 2.5 would be the better way to go, more widespread power and tons of tourque.

If you do go for the 2.5 make sure you uprate the gearbox, im risking it with a standard 2.0 5spd box so ieally go for a sti 6 spd or a ppg 5 speed if you can handle the whining from the box.

Jay

You don't need to get a straight cut PPG (the ones that whine) You can go for a helical (?) cut set, which is quiet.

Ns04

07 May 2008, 13:20

Cheers for the advice guys. I think I'm gonna go for the 2.5l Sti block. This is the second engine I've had in it in 2years, although this one was a replacement one not recon!!

Can anyone suggest a reputable (Cheap) dealer in the UK for the STi block?

Thanks

07 May 2008, 13:54

how about this;

AndyForrestPerformance

more specifically;

AndyForrestPerformance

07 May 2008, 14:08

Quote:

Originally Posted by SPEN555

how about this;

AndyForrestPerformance

more specifically;

AndyForrestPerformance

I'm pretty sure that GB has ended mate. It was a cracking price wasn't it!

That said, even at the normal rates, the 2.5 works out a very nice option for the road; here's what scoobymania offer.

ScoobyMania Online Shop

Ns04

07 May 2008, 16:24

I'm with 'Bighead' 2.5 everyday of the week. Its awesome, get it mapped right and the torque is nutty, it hurts your neck even under 4k

I can set off, drive, overtake and cruise in 4th gear......absolutely no regrets here!!!

<<<<<<<<<<<vms

07 May 2008, 19:28

Another vote for 2.5 conversion

07 May 2008, 23:13

Helical cut is not quiet. I know I have a PPG helical
But its very easy to live with :-)
But you do know that its not standard as it does make a noise like a constant quiet reversing noise - this is normal

If 2.5 litre is so good, then why does RCM not have this then........on their Gobstopper

07 May 2008, 23:43

Cheers guys,

I think I'll contact Andy Forrest to see if the deal is still available. It is still on his website.

Thanks to spen555 for the tip.

If not, the short block is still available for around £1500 from most UK suppliers.

Having looked at most of the options the 2.5l conversion looks like the best and definately the easiest!!

Thanks to everyone!!

07 May 2008, 23:44

Fang......I think RCM's car is a Track car which need to have a higher rev range ......and we use our car primary on the road

07 May 2008, 23:49

i went 2.0 forge build an think its great i also have the 5 speed ppg helical box an can not even hear it

08 May 2008, 06:44

Scoobymania - speak to Mike or Jase and they will talk you through the options on the block. A std new STi 2.5 bottom end is pretty good and would be more than good enough to give you the power you want.