360 versus 450 bhp... Wat is extra needed?

[1975DCS]

bigger downpipe and exhaust ?

One of those extra money costing things... I can walk away with my 2.5 inch when going to 360 bhp, but for 450 bhp it needs changing...

[1975DCS]

A 2871 will do 450 bhp http://www.s2forum.com/forum/showthread.php?t=5297

Regarding the compression, no all you have to is use a metal head gasket from an RS2
it will lower compression slightly but it will hold boost as the paper one on the 3B is naff.

Will this lower CR enough for 450 bhp? I don't know what the CR will have to be for 450 bhp, but I guess around 8.5-9.0:1?

Problem is I started with thinking of a smooth diesel like GT28RS and some RS2 parts and 325 bhp, than I thought: "well since my engine has already done some km's and is running 3B parts, it is better to re-new and upgrade the bearings and gasket (and seals)".

After that I thought "why not put in rods too and do it properly". Than my dad says: "if you're gonna do that, your engine is already open and maybe you need replacing pistons too". So that means half a rebuild and if you're going to do that why not lower CR and go for much more power... So from 3K euro I went to 4,5,6,7,8 (will it ever stop?).

And then thinking selling the Audi and putting the extra budget into it would mean buying some 2000+ performance motor like an Octavia RS, Golf GTI 25 Edition or similar and have no engine and gearbox worries. But trouble with this is that I will lose my previously big maintenance money for sure... Thankfully I could sell the AP's...

So still in doubt...

[S2 Ant]

I feel your pain on the starting off with something simple, then thinking if you're doing that then do something else and then that leads to something else etc etc

Deffo a v slippery and expensive slope to go down.

I can safely say tho, that even with the expense, i really regret selling my S2 and looking toward something modern and am trying to get my head (and wallet) round being able to get and play with another S2

[1975DCS]

Oh yeah! It al happend before...

First I had a Matra Murena 2.2 S. After engine failure completely 167 bhp rebuild and painted... Was even featured in a Dutch magazine! Not so good in comfort...

Second I had a 3dr Cossie, we bought this with a broken engine (to be sure it would be new) afterwards stage 3 (297 bhp) and some painting...

Third I had a Xsara VTS (exhanged this with the Cossie), best combo of handling and comfort of them all and best finished, but no turbo kicks...

Fourth I had an Astra F GSI with Turbo, but engine was not so good, so rebuild no3... Lots of too much overboost trouble with EDS chip (200 KPA) later solved with a V-Max chip (325 KPA). 276 bhp and 450 Nm and 6 speed this was the quickest of them all!
So qucik in fact: it beat a 997 Carrera 4S and could keep up with a 512TR and EVO 8 with HKS goodies (and 380 bhp, according to the owner). Good handling, but stiff comfort... Had cambelt pulley faillure, so head redone... The owner after that had oil/water trouble... Possible rust in feature?

Fifth I had an Astra G DTI. This was okay nothing more nothing less, but ever so slow and very noise when cold. Before going to the Audi I thought of doing this with a V-Max prepped C20LET engine conversion, capable of 330+ bhp

Sixth I have the Audi S2, this came from a collegae of my dad... So far spent only AP brakes and major service. Will it be the last?

[S2 Ant]

You've certainly gone round the houses to get to the S2 and without a doubt, the S2 will make you happiest, i can assure you of that!!

Just need to do it properly first time otherwise you'll only end up doing things again - plenty on here can vouch of that as well

[1975DCS]

You've certainly gone round the houses to get to the S2 and without a doubt, the S2 will make you happiest, i can assure you of that!!

Let's hope so...

Just need to do it properly first time otherwise you'll only end up doing things again - plenty on here can vouch of that as well

By properly you mean rebuilding the engine?

[S2 Ant]

Basically yeh :lol

I first looked at doing a couple of parts, but to get best use out of those i needed a couple of others, by doing those it would have been silly not to do something else which then resulted in more work and so it goes on.

I certainly wouldnt do half the job now if i was thinking about it, true it might seem overkill on some of the parts, but if the engine is out and being done it would be silly not to do everything - I think its a question of what you can afford really.

Personally if i was doing it (and could afford it) i'd do the lot, rods, pistons, crank balancing, lightend flywheel etc etc etc simply because to leave doing part of it and decide to do it later on, its all got to come back out which is more work in the long run really.

[rs2315]

Don't spend money on more and more horses.
Spend it on brakes and handling.
Who ever shi? themselves in a straight line??????
Well maybe Andy Green across the desert
rs2315.

[Corey]

Pistons are not needed for the bhp you are after, stock ones are more than capable. We've seen stock pistons go beyond 700bhp (after the crowns have had their CR dropped), a good set of rods and balancing will help you on your quest

[1975DCS]

Don't spend money on more and more horses.
Spend it on brakes and handling.
Who ever shi? themselves in a straight line??????
Well maybe Andy Green across the desert
rs2315.

AP's are already on the S2... And handling, well if I wanted a handling car I should have bought myself an Evo... No matter what we do with shocks and springs it will not change the engine position... And it does not benefit from active diffs either... It's not like a WRC... To be honest the Xsara was much better when turning in to a corner, the real quattro benefit is coming out of the corner..

[1975DCS]

Pistons are not needed for the bhp you are after, stock ones are more than capable. We've seen stock pistons go beyond 700bhp (after the crowns have had their CR dropped), a good set of rods and balancing will help you on your quest

Yes Corey, I know the stock ones (Mahle? Like my Cossy and C20LET had) are decent enough. It is not the piston itself that is worrying me, it is the possiblity that the pistons or cilinder walls needs refurbishing... After all it has done 240K (km's), thankfully the block seems to be of a good design and grade, so maybe no wear and therefore no need...

If only I could know if the pistons are not worn before starting it all*... If they where good I would stick to about 360-380 bhp with the least lag and save myself the hassle of buying a 3 inch exhaust (which means ditching my fairly new 2.5 inch exhaust) and putting in fancy new pistons (which will include a lot of extra labour). Also I would not have to worry about gearboxes... * I think this saves a total of 2-3 K euro...

I am not a big fan of machining original pistons or putting in double headgaskets, as this was done on faulty C20LET's too...

[quattrostyle]

After all it has done 240K (km's), thankfully the block seems to be of a good design and grade, so maybe no wear and therefore no need...

that what was I thought also till the head came off last weekend...