Tuning turbo time!

[Todger182]

If you manage to source the material for some valve guides let me know as i'm interested in a set of bronze guides for chalky.

I tried last year to source the material but failed on quite a few occasions, gave up in the end and just had some new "uprated" guides fitted.

Thanks

X

 

[craigb244]

I can easily machine guides up. wouldnt fancy doing 16 of the feckers tho... doubt brooky would either haha... but i guess it depends on how much people are willing to pay

 

[fingers99]

That's the problem really. There's so little off the shelf stuff for the FIRE engines and once you've counted in the cost of even a half-way decent head you can't afford any kind of failure. I think the colisbro ones for Zetecs are about 15 quid each, but that's for a part produced in relatively big quantities.

With people producing nearly 3 times the designed power output we really need some quantity production of forged pistons, stainless valves, alu/bronze guides, H beam rods, better bearings, etc.

I'll ask around.

 

[Munkul]

have you actually experienced problems with the standard ones, or are you just uprating them cos everyone else does on other engines?

 

[fingers99]

Pretty much the latter. The outputs people are now getting cannot be sustained without catastrophic failures at some point -- the failures in testing of the 16v 1.4 rods is fairly well known now, the det issues in the smaller 8v engine (whn tubbed) can only be solved by restricting power or by using shorter rods to allow decent sized ring lands, and so on.

All logic suggests that the laws of thermodynamics (and the good practice of performance engine building) do not apply differently to Toyota or Ford or Lancia than to FIAT Fire engines.

We've got to start doing it right or run into the practice of lifeing engine components like the Mini racers used to do.

 

[Munkul]

Lifed engine components, seriously :spin:

FIRE engines are 10 a penny. Fit decomp plate, tune it properly, dont push the turbo too far, and jobs a good un.

Even if engines get tired after 2 years or 30K who cares, you can buy a new one, fit a decomp plate, fit the engine, for around £350 or less. Obviously engines would last longer with less power or less man-foot, but thats not the point of doing it in the first place

Both me and jason are running around 160bhp on standard engines, IMO the key to reliable power is a well flowing turbo to allow power at lower boost and IAT. Not saying our engines are going to wear out much quicker either, since the rev limits are standard and lubrication/cooling is good.

 

[Todger182]

With any engine, it's all down to how well it's built but mainly, how well it's maintined after tuning.

Thanks

X

 

[fingers99]

Up to a point. It also depends on the materials used. I don't think Jason's -- or yours, have been running long enough to prove anything!

It depends what you want: you could buy 3 or 4 fire engines for the price of one decent cylinder head.

The mini racers were replacing major engine components every season, people running 100bhp n/a minis were rebulding every 10,000 miles...........

 

[Munkul]

Hang on - you're talking about n/a tuning as opposed to turbo? cut-back guides and high rev limits, and all the other things that wear out engines twice as fast?

Ive ran mine for 8k at current state of tune now, and pretty much every time its out its thrashed. Jason hasnt put as many miles on his though.

I know what you mean, but IMO the best bit about FIAT engines is that they are cheap to replace or fix, why make it expensive for some theoretical lifetime improvement? You read of people building massive spec engines that still blow up due to totally unforseen circumstances.

Anyways i'll go back into my box

 

[craigb244]

exactly. breakages are going to happen even with aftermarket stuff.
and personally id rather not spent thousands for just a tinny bit of reliability that might not even happen anyway, plus at the end of the day ANY high performance engine will never last as long as a standard engine.... how ever much money you throw at it. a engine with 2k worth of rods and pistons will still wear the bores out and loose power just as quick as one with standard items.



my car is maybe the second most powerful 1242 8valve turbo cento in the uk(?) ive yet to put bend/holes in the supposingly weak 16valve rods/pistons and my car is used every day. used for some pretty rough events (pct and autotest)
I drove my car fully loaded with the half cinq trailer also fully loaded with camping gear and beer. 70odd mile. car was on full boost 90% of the time if that never damagedanything nothing will(in its current state of tune).

every failure ive seen on a cento has been set up badly/cheaply. and all seem to be cars that have been set up by another owner/company.

not seen a engine failure on a car with aftermarket ecu.

Ive yet to see any hard proof on the power limit of components of these engines. lots of people saying they looked and "think" its xxxhp or my mates mate said they blew one up at xxxhp and it was xxxx fault

 

[craigb244]

also.... a while back my solenoid hose split. car boosted to over 3 bar(ecu wont read any higher) for a while (turned overboost cut off by mistake during a firmware upgrade)
luckily megasquirt is made to continue fueling in a liner rate after it leaves the mapped area.
boost temps where high but the power was unreal... couldnt imagine what it was but the car wheel span in every gear and slipped the clutch (200mm stilo)

engine suffered no det and is still running perfectly now

 

[fingers99]

a engine with 2k worth of rods and pistons will still wear the bores out and loose power just as quick as one with standard items.

Ive yet to see any hard proof on the power limit of components of these engines. lots of people saying they looked and "think" its xxxhp or my mates mate said they blew one up at xxxhp and it was xxxx fault

Bores are one thing, decent heads are quite another. Good quality pistons and rings will last longer than stock ones. A good H beam rod should last forever.

The hard proof is in the 1.4 16v turbo engine. It has better rods, better pistons and maybe better other stuff. People who have tried to develop the n/a engine past 140bhp have come seriously unstuck. Don't you think that if it could be done reasonably cheaply and waranteed folk like BBR and even GSR would be doing it right now? There's a real market for a cheap 500 with better peformance than an Abarth SS.

Flash figures and errors don't cut it compared to the tests that manufacturers and serious developers do.

 

[Munkul]

we have heard about the 1.4 weaknesses, whereas we've actually proved the 1.2 so far.

GSR Peter still thinks the 1.2 16v bottom end is only good for 140bhp which is blatently ballcocks, with evidence to prove at least 160-170bhp and up to 200bhp is capable from standard pistons, rods and crank, with at least some meaning of longevity. Of course, this is turbo application only.

Me, Craig, Tricker, Jason, Davethetrike, theres a few more I cant remember, plus all those who dont post their stuff on the tinterwebs... Hopefully people pushing these engines towards the 200bhp mark will become more common as well.

Tuners are more willing to push engines to their mechanical limits than manufacturers for obvious reasons.

Yes its pikey as feck, to just keep pushing til something breaks, but come on, its only fiats we're playing with, whats the point in spending big bucks?

 

[Todger182]

The 1.4 16v engines are just as tough as the 1.2 16v.

I have a set of kritips old pistons and they have given up before the rods, and that was just overfeuling. If anything the rods are the strong point.

There is some polish 1.4 16v rally cars that are pushing 160bhp on standard internals, just head work, throttlebody or plenum bodies, and lightened flywheels.

One of them was an overbored 1.4 16v engine pushing nearly 180bhp n/a

Thanks

X

 

[craigb244]

fiat would of beefed stuff like that up just because its a production car. my engine might only last a few thousand miles while that car is expected to be used and abused and still last.

unlike minis and other cars fiat does not have a huge tuning background. i never believe what i read online. even more so when there is no hard evidence then some random guy/company saying this and that.

as munkel said. our engines are pennies. if you are in no hurry you can get given them if you know the right people.

i have 3 8valve engines fitted with 16valve pistons, smoothed and port matched head/manifolds that ive built up over the last year and half. think so far all 3 have cost me about £150.

whats £150? a single H-beam rod? 2 forged pistons?

and at the end of the day if you spend thousands on a super forged everything engine your never going to win anything just loose loads of money.

centos never will be part of a multi million pound rally team which needs a super reliable powerful car. its never going to be a high performance car that is part of any class it will be good in... spending all that money on a car that will just be ragged up and down a motorway maybe do one or two track days a year and go down the strip a few times seems very excessive.

the only real benefit of buying and using all that stuff is pub talk and bragging rights.

my bragging rights are:
how little ive spent for the performance.
the fact that its all my own work
the fact that it works and is so reliable with what ive got... people are surprised and fascinated when i explain about fitting 16valve rods and pistons. dont think the same could be said if i told them i simply dropped 2k+ work of rod and piston into the engine (most likely they would think you have a screw loose for putting that much money into a £500 old fiat and personally I would to haha)

 

[craigb244]

munkul and todger i never just copied what you said... just took me a while to write haha

 

[fingers99]

think Peter was talking of the 1.4 engine, not the 1.2. My guess/explanation is that the earlier 1.2s had rods formed by now largely obsolete practices which are stronger than more recent rods which may be "split forged".

No professional engine builder will work with split forged rods. Someone begining with B told me that GC no longer works with engines without forged H beam pistons, but I've not talked to Guy himself about that, so don't take it as gospell. GC doesn't mess about, nor does anyone else telling you to use forged this, H beam that, bronze or stainless t'other.

I'm not against the cheap and cheerful approach -- but it does have its limits.

Of course, on Blue 2 I'll be following another course of action -- stick an engine that was properly built in the first place in the back of it. MR2 tub needs little more than a decent turbo, forged pistons and a better clutch to make 350bhp all day, any day -- already has sodium filled stainless valves and bronze guides. About a thousand quid for a nearly new one from Japan...........

 

[Munkul]

Peter was talking about both 1.2 and 1.4 bottom ends, he's mentioned it several times on his and other forums, and he told me personally when i spoke to him over the phone.

Thats why im sceptical of the stories of the 1.4 being weak as well - look at todger's post

Obviously you would uprate the pistons, rods, etc etc etc if you were going all out with no budget restriction, but who has done that so far on FIRE builds?

Here's another case in point - Some people say sr20dets need forged pistons and rods past 350bhp. Some people will forge their engines just for 350bhp. Others, plenty others I might add, have run over 400bhp with nothing but an uprated head gasket. So whats the point? Yes you are pushing parts onwards to their limits, but with replacement engines starting at £400-£500, you can afford to pop one or two for the sake of experimenting, since a forged rebuild is the wrong side of £1500.

So yes, in the long run you have the reliability of a forged engine when pushing the standard parts beyond their comfort zone, but then someone next to you says they're ran exactly the same power for years and spent £1000 less...

Meh, this argument is going no-where.

 

[craigb244]

GC may of said they wont touch standard pistons but iirc brooky bought them rods from here because GC ones where expensive.... makes me wonder if GC say that so you buy hes rods (brookys ones where one offs)
i bet if you told GC you wanted standard pistons i highly doubt he would turn down the work

either way a few of us are pushing the hp up bit by bit and so far no failures. im willing to keep going but I think ill give up pushing it before the engine gives up

 

[fingers99]

Rods, not pistons. And then (talking of engine builders in general, no-one in particular), it'd depend how much of the engine you were building. Reputation means an aweful lot if that's all that puts the food on the table.

Todg, I'm pretty sure those pistons were 1.2 ones -- the ones that cracked due to det (we think)?

At the end of the day I'd like a Cinq tub that can fight duels with 7 series BMWs, win, and not leave oil over their windscreen............