2.5 / 2.6 L conversion advice wanted.

[GazzaG60]

700 is a lot isn't it.

i see the point jamo but you wont feel 50hp at 600hp plus numbers i dont think. area under the curve id expect you will. like i say if you are going to build you may as well build a stroker.
im not after a dyno queen anyway.

i dont think the OP is looking at high enough figures to warrant the need unless its a want. nothing wrong with wanting.

[MGaz]

Hmm 2.2 can make power but not more than a stroker, i've not seen a 2.2 hit 1400 bhp like some of the stroker engines by Jonus and the Scandinavian crew

Until you've driven one you can't understand why you would want one, power delivery and torque low and mid range punch is so much better.

2.2 is better for track / hi revving focus as you can get them up to 8500-8600 rpm

Stroker is a street or balls out drag engine

All said don't knock them they have their place, I know members on here trying to tell me not to do it and stick with 2.2 and now they are building strokers engines

keep the 2.2 in this case, the bigger turbo like rusty says for this powerlevel is very good

That was kind of my reason for wanting the stroker.

I wasn't thinking about BIG power, or making more power than a tuned 2.2L engine.

Tho admittedly my experience with the 2.2 20vt is minimal , the idea in my head was however that a 2.5L would 'naturally' produce more grunt low down.. & more power than standard but with MUCH better response, & it would improve on that power 'without' increasing lag..

I guess what i'm saying is, even tho I see that the 2.2 20vt will easily make more power than my car has at the moment when motorway driving, i'd still like to retain some of that NA characteristics where by you plant your foot on a country type lane or up/down back road, and the power kicks in strait away.

even the standard 2.2KV was good at this. there was no waiting around for it to do something, before coming to the next bend or elevation change, & having to change direction & speed You hit the throttle and it just gos! before having to get on the brakes again for the next turn


will a 2.2 20vt do this? I don't know, you tell me?

[Jamo]

You do know that the RS2 turbo will produce 600nm of torque on the 2.2? Infact it can produce enough to bend the stock rods

This would be the route I would go if you can't get the 92.8 crank or else your looking to go diesel block and crank

You haven't yet experienced the 2.2 20vt so personally use that get it homefried to near 300bhp then decide if you want to stroker it. The turbo car is a different animal to a NA.

[Nik0las]

Jamo,

what is the case with the diesel block and crank? Rods, Pistons........?

[MGaz]

700 is a lot isn't it.

i see the point jamo but you wont feel 50hp at 600hp plus numbers i dont think. area under the curve id expect you will. like i say if you are going to build you may as well build a stroker.
im not after a dyno queen anyway.

i dont think the OP is looking at high enough figures to warrant the need unless its a want. nothing wrong with wanting.

I must admit the 'Wanting' factor does indeed come in to it, just a little. :mischeif:

You do know that the RS2 turbo will produce 600nm of torque on the 2.2? Infact it can produce enough to bend the stock rods

This would be the route I would go if you can't get the 92.8 crank or else your looking to go diesel block and crank

You haven't yet experienced the 2.2 20vt so personally use that get it homefried to near 300bhp then decide if you want to stroker it. The turbo car is a different animal to a NA.

your right, It would be better to experience 300bhp 2.2 20vt in my car first, and see what i think. but I just thought the extra cubes in the 2.5L would make the car more 'drivable' & the overall characteristics of the engines power delivery would be improved noticeably.

Because I can say with first hand knowledge that the extra cubes in my 2.5L GTi engine (although not turbo) improved the overall 'driving experience' to a much, much greater extent than it improved the dyno reading. it was just a MUCH nicer car to drive with the bigger engine.


Would the same not be true for a 2.5L 20vt regardless of how much or how little power it was making?

"There's no replacement, for displacement"

[GazzaG60]

the nicer experience is due to the area under the curve. the small turbos do this for you. the bigger ones capacity helps.

the enhanced feel im sure jamo will agree comes with the stroker T lump too.

the same would be the case. just i work on a bang for buck principle. my full build id expect costs less than a stroker block. i make 500hp there or there abouts.

boost is a good replacement for displacement.

[Jamo]

I must admit the 'Wanting' factor does indeed come in to it, just a little. :mischeif:





your right, It would be better to experience 300bhp 2.2 20vt in my car first, and see what i think. but I just thought the extra cubes in the 2.5L would make the car more 'drivable' & the overall characteristics of the engines power delivery would be improved noticeably.

Because I can say with first hand knowledge that the extra cubes in my 2.5L GTi engine (although not turbo) improved the overall 'driving experience' to a much, much greater extent than it improved the dyno reading. it was just a MUCH nicer car to drive with the bigger engine.


Would the same not be true for a 2.5L 20vt regardless of how much or how little power it was making?

"There's no replacement, for displacement"

Yes and no, your going to be running 400-450 minimum on a stroker setup as smaller turbos will surge badly so your entry level is RS2 / 3071 and even these are too small for the engine as max hp will be made well before the engines rev out.

Nice driving yes it will but you haven't driven a 2.2 turbo yet!

Bang for buck is subjective IMO, my engine was built for less than a complete rebuild of a 2.2 engine

[Nik0las]

Jamo I think you miss my questio above ,

what is the case with the diesel block and crank? Rods, Pistons........ etc ?

[Jamo]

Jamo I think you miss my questio above ,

what is the case with the diesel block and crank? Rods, Pistons........ etc ?

That is to long to explain in one post and there is no right way to do it,

search the forum for stroker and you will see various projects that have taken different approaches to it.

[Rusty]

will a 2.2 20vt do this? I don't know, you tell me?

On a small turbo (K24 7000) it's not instant but that's as much down to the mapping as anything else. With a 2.2 bar WG spring it'll be bloomin' fast spool up and if you thought the KV is torquey then wait till you try a 20VT, they're pretty good above 2.5k TBH.

With a decent inlet and exhaust, a single mass flywheel and perhaps even a little flow job, you're looking at decent performance between 3k and 7k, not explosive but very, very useable on the road. With the short CQ gearing you'll have a very fast car with 300bhp. As Chris (Yogi730) found out, that gearing is so short that laggy turbos just don't work in the lower gears.

As before, get it fitted and working, get the chassis sorted and maybe even a 3B or ABY gearbox and then decide where to go with it. I'd suggest that a properly built 2.2 with an RS2 turbo is pretty much the best setup in terms of compromise, it's got enough performance on the road and will be reliable as it's pretty much bolt-on parts.

Just my 2p from sitting on here, reading, listening and watching previous projects

[AndyP]

How much are they? 700 quid I think C&R were asking when I enquired

Thing is Andy you have a stroker engine not installed yet spend the money on that unless your thinking of having another I5 car?

You can never have too many engines

But you are right and that's what swung it in the end, I need to concentrate on finishing one project before starting another!

[MGaz]

On a small turbo (K24 7000) it's not instant but that's as much down to the mapping as anything else. With a 2.2 bar WG spring it'll be bloomin' fast spool up and if you thought the KV is torquey then wait till you try a 20VT, they're pretty good above 2.5k TBH.

With a decent inlet and exhaust, a single mass flywheel and perhaps even a little flow job, you're looking at decent performance between 3k and 7k, not explosive but very, very useable on the road. With the short CQ gearing you'll have a very fast car with 300bhp. As Chris (Yogi730) found out, that gearing is so short that laggy turbos just don't work in the lower gears.

As before, get it fitted and working, get the chassis sorted and maybe even a 3B or ABY gearbox and then decide where to go with it. I'd suggest that a properly built 2.2 with an RS2 turbo is pretty much the best setup in terms of compromise, it's got enough performance on the road and will be reliable as it's pretty much bolt-on parts.

Just my 2p from sitting on here, reading, listening and watching previous projects

just say I stay with 2.2 liters. How much bhp and torque can I expect to make before entering the realms of noticeable LAG and loss of responsiveness, so that the car still remains fun in real world driving situations on normal roads & twisty country lanes. Rather than ending up only good for point and squirt drag racing and track days.

is 350bhp achievable while still keeping the everyday/any road fun factor? Or can I set my sights higher? or should they be lower?

TBH. as for what I really want from the car, If the end result is something that will burn off the new 5 pot TT RS, i think I'll be more than happy enough with that. (at least for the moment)

[Rusty]

With stock internals 350 is a reined in RS2 setup and will be marginally more laggy. With uprated internals the world is your oyster, it's all down to hardware, A/R and mapping after that.

To say it again, stock with a chip is more than enough to get you started and in a light car, it'll work very well indeed.

[Rusty]

With stock internals 350 is a reined in RS2 setup and will be marginally more laggy. With uprated internals the world is your oyster, it's all down to hardware, A/R and mapping after that.

To say it again, stock with a chip is more than enough to get you started and in a light car, it'll work very well indeed.

[pnanassy]

Altough its not cheap,the 2.5 build well worth the money.Very responsive,and no need to rev it to hell.This one is a 2.5 with GT30R,and VEMS tuned by me: