The goal ....to get from 300bhp to 430bhp as safe as realistically possible & over engineering where feasable within budget.

Ok, thought I'd open it up for advice....however, please PLEASE P L E A S E dont give me loads of 'dont do it' crappy comments & subjective opinion Just want good ol'fashioned objective advice & experience. Carlt, be good! If this offends your sense of purpose in life then dont read on!

What I have now: (rated at 300.9bhp)
- GTiR
- Blueflame turbo back with sports cat
- PA SIP & FMIC
- Gtech 2
- Bailey DV
- K&N filter
- Greddy
- Walbro 255
- Bilteins / Eibachs

My budget is around £9k to get & fit & RR at PT. It must all work with standard ECU as thats out of my league. Whats on the way:

- Stilo Abarth crankcase (extremely rare) with additional stengthening
-forged 83.5mm pistons with uprated gudgeon pins all balanced within 1g - rated at over 800BHP combined
- long throw (modified ratio) super lightweight titanium connecting rods all balanced within 1g rated at over 900lbs/ft combined
- forged, nitride hardened crankshaft
- balancer shaft removal
- new oil pump
- oil pump and crank main gaskets provided
- sump
Total capacity = 2475cc
- 6 point paddle shift (bought already)
- 5 stud downpipe with lambda
- Nigels GB DBA brakes & pads (must add my name!)


Heres what I also need:
- Head......stage 2? 3? Any up for sale?
- Turbo....will be big, but not decided...ideas?
- Injectors....no idea yet...anyone?
- Lightened flywheel....Good idea??
- Cam belt pulley protector thingy!
- FPR.....but which?
- ported mainfold....
- 3.8bar bosch FPR...sound ok?

Bet theres loads of other stuff I COULD get, but what do I NEED to get? Just talking engine at moment, not handling.

Hit me with it.....keep it good natured Im a defensive bugger at times.....but you know that!


Chris

ported/tubular manifold?

and what mapping solution are you going to use?

Gearbox ? What is the gearbox rated too on a coop ?

i would also personally budget for improving suspension and brakes!

i know you already have bilsteins/eibach, but things like uprated ARB and Poly Wishbones!

very interesting chris.

im a believer in getting everything 'over-engineered' so to speak, gives you peace of mind rather than worrying its all going boom every ten seconds.

thought about anti-lag of some description if going for a huge turbo, or will the 2.5 perform well enough off boost anyway?

You've missed off the ECU plus mapping - somewhere between £1500 and £3000 depending on the hardware and the proficiency of the mappers

You *might* get away with the stock Motronic, but probably not with a 2.5 conversion - the MAF will be maxxed out before the turbo has spooled up

Turbo - you're going to be looking at a GT30 of some kind (GT28 series is getting close to its limits at your target bhp)

I know you said you didn't want any "don't do it" posts, but here's a couple of "why do it" questions

1) If you wanted to spend £9k on a mad Coupe, why didn't you just spend £11k on JohnS' car?
2) If you want a reliable 430bhp, why go for a 2.5 conversion? Its quite possible using 2 litres and you'd save a truckload of cash (although I accept that a 430 bhp 2.5 will exhibit very different characteristics to a 430 bhp 2.0)

so - not really a "don't do it" - more of a "do you REALLY want to do it THAT way?"

i'd agree with point 1 that Nigel made! you have a ready made 2.4 600bhp waiting for, which a month or so ago you were guttedyou missed out on! with great stopping power and handling and a MOTEC!

but if you want to do it, then go for it!

also things like this never work to budget!

Thats pretty damn close to 'dont do it' Nigel! And I did say it must stay standard ECU....when I edited it! If that means a drop to 400bhp then thats the deal.

JohnS car has done 100k miles more than mine & its more fun doing it yourself! Hell you should empathise with that!

if you are going for bigger injectors there is no need to go for a higher fuel pressure!

can I ask how you came up with 430bhp, seems bit of a random number?

Thats really helpful Eldinho....I'll come back later

ps...430 was on back of some USEFUL advice from JohnS.

This forum & clique opinions! Sure you mean well but reads like you havnt read my post!

Chrisbp, as mentioned by Nigel, your AFM is going to be maxxed out so early, that it will be a risk running an engine when you have no proper fuel control over it on a std ECU, when PT can't quite sort out the mapping issues associated with this.

You will either have to look at a bigger AFM (which i believe no one has done) or swap to a map sensor setup (again, not done, unless you go MoTeC) So just giving you a word of caution.

Taz might be able to shed more light on the AFM / power limiations.

pretty sure that some of the Greek cars (not necessarily 2.4) are running custom large AFMs (and one of the tuners can actually get them to work)
As far as I understand it, they use a larger tube to stick the MAF element in and then somehow they retune the whole function in the ECU, but don't quote me on that.

V.

I remember ages ago reading that Taz was planning to just what you’ve mentioned there Vas. I’m unsure if he actually ever put it into practice but as mentioned above definitely worth picking his brain.

Other than that, I’d say ditching the cat altogether would help (if you are happy to run it like that) and probably get rid of the bailey dv for something not quite so pants.

How many Kg of air does the standard AFM Max out at? What BHP does this roughly equate to?

IIRC, the standard MAF is maxxed very soon after the standard bhp is exceeded.

Chris - I would be VERY hypocritical if I actually said "don't do it". However, when I did it, I tried very hard to learn from the few people that had already done it.

Your target bhp is the issue. There are some fundamental issues with your plans.

If you can "put up with" 400bhp, then you can do it MUCH more cheaply than a 2.5 conversion (as I have proved).

If you MUST stay on the Motronic, you will struggle to get a 2.5 to run well.

I really would like to see another big-power car on the forum - we need some more runners at TOTB.

However, there would appear to be a little confusion in your plans (unless, as it would appear, there is rather more information that you've gleaned from JohnS that you haven't told us yet)

If you genuinely want a 2.5, 430 bhp is trivially easy to achieve - why isn't your target rather higher?

Taz is running his car OK with the std ECU so it is possible on a 2.4. 430BHP is roughly where I would say the threshold was for a single plate clutch and also equally for the std engine management.
There are both larger diameter pipes to fit the std maf in and larger mafs out there that are compatible. To be honest it is worth converting to a larger MAF housing whether your 350BHP on a 2.0 or 2.5 let alone 400BHP. There is a readily available 80mm Bosch MAF which is not a ridiculous step up but can measure about 10% more air.

Target is limited by fact I want to run the standard ECU. Change the ECU & it adds about £5k it seems to me all in.

On the turbo, I guess a GT2871 should do the trick for your BHP target? Probably worth talking to Perfect Touch to see what's possible on the mapping with the stock ECU and on injector sizing advice? Edit: on the heads for sale question, I think Kenno was toying with the idea of selling his a while back .. although Barbz is still doing them last time I checked.

It sounds like youre keen on doing the work yourself... Then why dont you mount the ECU yourself? http://www.vems.hu - This ECU supports all the things on the 20vt, but you need to solder some of the board, and ofcourse tune the engine. But the price is only about 500£, and that is with knock control, boost control, WB controller and sensor, EGT controller and sensor etc. etc.
I have just ordered my system - hoping to have it running in about 1-2 months (not in a hurry).

This is just an idea but could you run TWO induction pipes, each with its own Coupe MAF sensor and then combine the signal in some way? That should effecively double the sensitivity...

Piping might be a bit tight / difficult and you would have to run 2 air filters.....

What do you think?

Running bigger than 440cc injectors for the Motronic can be a problem because the injector pulse width i.e. injector lag, cannot be reduced enough especially at idle and part throttle. This may be possible with a larger MAF housing but I tried this initially however PT eventually gave up on it as they couldn't make it work. It doesn't matter so much if the MAF is maxed out as long as maximum boost is fuelled for this. The problem exists when running lower boost as the MAF will still be maxed but you will run too rich.

The most notable limiting factor for high power is the manifold and head. The shortest primaries are 4 & 5 which is where you are most likely to melt a piston due to reversion and resultant high EGTs. Going beyond 450bhp is hard whether it is a 2 litre or 2.5 litre on the standard manifold.

Re the single plate clutch, tbh John I reckon it's good for 500bhp and 420lbs/ft I have no doubt that my clutch has taken more abuse this last 18 months than any coupe ever... and it has never once let me down, just beautiful

Hi Flea, thanks for that. The head Im looking into & spoken to Nitrous. He has a couple for sale....any thoughts? Not read much about uprated manifolds, any pointers? As for standard ecu....you reckon 430bhp is realistic or not?

Appreciate your input Flea

Chris

auto integrale do a tubular manifold, which is a squeeze with AC but apparently it does fit! think its just short of £1k!

ported manifolds are supposed to be good enough up to around 450bhp! not sure if Barbz will still do this though as it gets done on the owners own manifold! but other places should be able to do it!

what kind of work is done on Nitrous's Heads? Barbz can still supply heads!

I'm not sure I understand, why does the ecu have to remain the same, yet everything else get a change. Is it the porr relation? You might as well say I want X bhp on the standard turbo. REeally for the outlay I would be looking to cut it short just because I have some strange need to retain the std ecu. Dont let that hold you up, you can decide on the electronics further up the road.

Rich

Rich to change the ecu just seems to bring soooo many more issues & the costs is silly money. I read the motronic v...thread & lost the will to live!

Why not buy johns car and swap the engines over then sell it?

If you're paying 9k anyway why not pay a bit more and really the amount of power you'll be getting out of it?

how about nitros. im sure thats a cheap way of getin more bhp

Ooooooh which bits??? Oh all the bits that are mileage irrelevant by any level?

Its a proven car, that is ready to use. Seems ridiculous to me, no offense that there's a car thats built to the highest spec and you want to near copy it, and you will spend more than he wants for the spec and the car its in. (in a better colour and better looking too IMHO)

As for doing it yourself, which bit? Paying, ordering etc?

I'd snap his car up if i were wanting to do this, what your doing.

Wudnt be paying a bit more....a lot more