Fiat Coupe Club UK

2013

Posted By: Anonymous

2013 - 19/12/2012 21:10

What sort of mad power will we see in 2013 mid-high 600bhp monster coupes on fiat power plants
Posted By: Anonymous

Re: 2013 - 19/12/2012 21:15

Watch this space laugh
Posted By: knight7660

Re: 2013 - 19/12/2012 22:24

I'd only go for 600+bhp if the power band is wide ie 4k rpm width of power at least.

Until we are at this stage I'm not bothering.
Posted By: Anonymous

Re: 2013 - 19/12/2012 22:44

Originally Posted By: knight7660
I'd only go for 600+bhp if the power band is wide ie 4k rpm width of power at least.

Until we are at this stage I'm not bothering.


You'll be waiting forever as 600bhp+ on a small displacement engine inherently goes hand in hand with a narrow power band and lots of laaaaaaaag.

Ask Johnny. His car starts spooling at 7.5krpm. laugh
Posted By: Burbum123

Re: 2013 - 19/12/2012 22:45

I Would be very very surprised to see one beat JBT'S but you never know. smile
Posted By: Countrycruising

Re: 2013 - 20/12/2012 00:53

Originally Posted By: Burbum123
I Would be very very surprised to see one beat JBT'S but you never know. smile


lol, keep watching this space laugh
Posted By: Per

Re: 2013 - 20/12/2012 00:56

I'd stay at 340hp (did I say that? yes!) and then also use my (100hp) 125S. Old man I am...
Posted By: Anonymous

Re: 2013 - 20/12/2012 08:19

Originally Posted By: Biggenz
Originally Posted By: knight7660
I'd only go for 600+bhp if the power band is wide ie 4k rpm width of power at least.

Until we are at this stage I'm not bothering.


You'll be waiting forever as 600bhp+ on a small displacement engine inherently goes hand in hand with a narrow power band and lots of laaaaaaaag.

Ask Johnny. His car starts spooling at 7.5krpm. laugh



Don't give the clue away mate.
Would be nice to see a 2.0 actually break 500bhp next year too.
Posted By: Freddan72

Re: 2013 - 20/12/2012 08:39

I would like to join the 400 hp club in Sweden. But it would be pretty lonely there. I would be the only member laugh
Posted By: Anonymous

Re: 2013 - 20/12/2012 08:55

Originally Posted By: johnnybravoturbo

Don't give the clue away mate.
Would be nice to see a 2.0 actually break 500bhp next year too.


You're just jealous that I'm above you in the dyno league table. laugh
Posted By: Anonymous

Re: 2013 - 20/12/2012 08:56

Quote:
lol, keep watching this space


Why limit yourself to one where there will be many laugh
Posted By: Anonymous

Re: 2013 - 20/12/2012 09:04

Quote:
Would be nice to see a 2.0 actually break 500bhp next year too.


On heartbreaker too, with nothing switched off or on. laugh
Posted By: Anonymous

Re: 2013 - 20/12/2012 09:22

Originally Posted By: Biggenz
Originally Posted By: johnnybravoturbo

Don't give the clue away mate.
Would be nice to see a 2.0 actually break 500bhp next year too.


You're just jealous that I'm above you in the dyno league table. laugh



Next year will bring a new table ,the table of truth my friend.

No pub figures just actual power,.
What's the point in having length if you can never use it laugh
Posted By: Anonymous

Re: 2013 - 20/12/2012 09:57

Originally Posted By: Barbz
Quote:
Would be nice to see a 2.0 actually break 500bhp next year too.


On heartbreaker too, with nothing switched off or on. laugh


cool tongue evil
Posted By: knight7660

Re: 2013 - 20/12/2012 10:21

well whenever the table of truth comes in I hope we have some graph action readit so we can see who has the best power band and not just pub numbers judge
Posted By: Anonymous

Re: 2013 - 20/12/2012 14:35

Originally Posted By: johnnybravoturbo

Would be nice to see a 2.0 actually break 500bhp next year too.


As I recall. my 2.0 was running 587 back in 2007, even allowing for race fuel

The only reason we won't be getting 700 from the 2.4 is I don't need 700 as much as I need a decent torque spread, so have cams timed up to suit my requirements rather than outright numbers

Might not be run up before 2014 though even though the lump is built and ready, its the car that's the hold up frown
Posted By: Anonymous

Re: 2013 - 20/12/2012 14:56

Originally Posted By: nyssa7
Originally Posted By: johnnybravoturbo

Would be nice to see a 2.0 actually break 500bhp next year too.


As I recall. my 2.0 was running 587 back in 2007, even


Wasn't that a bomb, rather than an engine though? wink
Posted By: Anonymous

Re: 2013 - 20/12/2012 16:56

Got quite a few races out of it before snapping a rod on the "slowing down" lap
Posted By: knight7660

Re: 2013 - 20/12/2012 17:04

did you have any graphs for that nyssa? what are you planning to get out of the 2.4l build aswell
Posted By: Anonymous

Re: 2013 - 20/12/2012 18:30

Originally Posted By: nyssa7
Got quite a few races out of it before snapping a rod on the "slowing down" lap

Terror
Posted By: Anonymous

Re: 2013 - 20/12/2012 19:07

Originally Posted By: nyssa7
Got quite a few races out of it before snapping a rod on the "slowing down" lap


I was just teasing you Trevor...
Posted By: kj16v

Re: 2013 - 20/12/2012 19:49

I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh
Posted By: Anonymous

Re: 2013 - 20/12/2012 21:32

Originally Posted By: kj16v
I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh


Never mind onto the road. A lot of the flywheel figures 'obtained' are very easy to blow out of the water. They require a VE of over 100% (N/A - and never seen on any turbo engine due to the necessary timing of the exhaust cam) - not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....
Posted By: Kayjey

Re: 2013 - 20/12/2012 22:58

Next year = more NOS.
Posted By: Anonymous

Re: 2013 - 20/12/2012 23:50

Originally Posted By: group5lancia
Originally Posted By: kj16v
I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh


Never mind onto the road. A lot of the flywheel figures 'obtained' are very easy to blow out of the water. They require a VE of over 100% (N/A - and never seen on any turbo engine due to the necessary timing of the exhaust cam) - not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....


I love your posts,
You talk so much sense.

Pity you don't post more fella thumb
Posted By: Per

Re: 2013 - 21/12/2012 01:33

Originally Posted By: group5lancia
Originally Posted By: kj16v
I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh


Never mind onto the road. A lot of the flywheel figures 'obtained' are very easy to blow out of the water. They require a VE of over 100% (N/A - and never seen on any turbo engine due to the necessary timing of the exhaust cam) - not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....

So true.. On paper mine is far from the powernumberjunkies in sweden. Still it seems as quick on the straights.. smile
Posted By: Nigel

Re: 2013 - 21/12/2012 09:22

Originally Posted By: johnnybravoturbo
Would be nice to see a 2.0 actually break 500bhp next year too.


I could have seen 500 if I'd instructed Leighton to run 1.7 or 1.8 bar, but I wasn't interested in peak power.
Posted By: Anonymous

Re: 2013 - 21/12/2012 10:01

Originally Posted By: johnnybravoturbo
Originally Posted By: group5lancia
Originally Posted By: kj16v
I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh


Never mind onto the road. A lot of the flywheel figures 'obtained' are very easy to blow out of the water. They require a VE of over 100% (N/A - and never seen on any turbo engine due to the necessary timing of the exhaust cam) - not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....


I love your posts,
You talk so much sense.

Pity you don't post more fella thumb


Few people want to hear the truth, I fear...
Posted By: Anonymous

Re: 2013 - 21/12/2012 14:04

I have no fear as I know the truth laugh
Posted By: sherlock

Re: 2013 - 21/12/2012 15:00

Originally Posted By: group5lancia
not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....


So what your saying is Fiat/Lancia really pulled it out of the bag when they put together the 5 cylinder engine?!
Posted By: Anonymous

Re: 2013 - 21/12/2012 15:46

Originally Posted By: johnnybravoturbo
I have no fear as I know the truth laugh


And so do I Johnny boy, so do I... wink
Posted By: Anonymous

Re: 2013 - 21/12/2012 15:58

Originally Posted By: sherlock
Originally Posted By: group5lancia
not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....


So what your saying is Fiat/Lancia really pulled it out of the bag when they put together the 5 cylinder engine?!


No Barbz did thumb
Posted By: Anonymous

Re: 2013 - 21/12/2012 18:49

Originally Posted By: knight7660
did you have any graphs for that nyssa? what are you planning to get out of the 2.4l build aswell


Think I posted up http://www.nyssaracing.com/562.jpg originally, the Cyprus engine first map with GT30, but went back a few weeks later with more changes, swirl pot and new pump using the Mitsu Evo one purely as a lifter, and one of the silencers removed so pipe exitted behind driver's door. Mark @ Owen told me that run was 587 but never got round top getting the graph

Had enough fun on track for those it went past to fully believe the figures

Only really targeting 550 with the 2,4 but to come in lower and with bigger torque spread - but if more comes at sensible boost levels, that's where it will run
Posted By: knight7660

Re: 2013 - 22/12/2012 19:46

more graphs the better that way we can all see the results of different specs.

ive been looking at most of the big power coupes to work out the next stage il be going for but im missing an important one frown
Posted By: Anonymous

Re: 2013 - 22/12/2012 21:03

Originally Posted By: knight7660
more graphs the better that way we can all see the results of different specs.

ive been looking at most of the big power coupes to work out the next stage il be going for but im missing an important one frown




Which cars that

Posted By: Anonymous

Re: 2013 - 22/12/2012 21:32

Quote:
but im missing an important one



I'll put my latest graphs up shortly then. wink
Posted By: Anonymous

Re: 2013 - 22/12/2012 21:39

Good lad,joes brother Adam does have a point.

Although with what I saw it might knock the odd beek out of joint.

As joes brother Adam rightly points out the spread of power is important.
You have nothing to worry about there Barbz .
Posted By: Anonymous

Re: 2013 - 27/12/2012 19:47

Originally Posted By: group5lancia
Originally Posted By: kj16v
I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh


Never mind onto the road. A lot of the flywheel figures 'obtained' are very easy to blow out of the water. They require a VE of over 100% (N/A - and never seen on any turbo engine due to the necessary timing of the exhaust cam) - not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....


What does VE have to do with anything on a boosted engine, VE is not the limitation on the output of a boosted engine. But maybe you have a logic to your conclusion, how are you defining VE in this application?
Posted By: Anonymous

Re: 2013 - 27/12/2012 19:52

Originally Posted By: sediciRich
Originally Posted By: group5lancia
Originally Posted By: kj16v
I hope next year brings a Table of Speediness too. See how many of these pub figures actually make it through the flywheel and on to the road! Bet that'll bring a few surprises laugh


Never mind onto the road. A lot of the flywheel figures 'obtained' are very easy to blow out of the water. They require a VE of over 100% (N/A - and never seen on any turbo engine due to the necessary timing of the exhaust cam) - not even F1 engines of 'The Turbo Era' managed the claimed levels per litre and per level of boost....


What does VE have to do with anything on a boosted engine, VE is not the limitation on the output of a boosted engine.


Of course it isn't... what would I know...
Posted By: Anonymous

Re: 2013 - 27/12/2012 19:59

well tell me what you do know instead of taking the hump because where I'm at you are confusing VE on a NA engine with some limitation of excess delta in compressor output to that seen at the valve i.e. meeting the limit of flow on the engine, you'll need to explain more and trust me Im quite capable of understanding someone else's interpretation.
Posted By: knight7660

Re: 2013 - 27/12/2012 20:25

Originally Posted By: Barbz
Quote:
but im missing an important one



I'll put my latest graphs up shortly then. wink



your 2.4 is the one i always watch out for because i like to see what move you get out of it after each improvement. smile

also it will be good to see the difference in power bands the extra cc brings with barbz's 2.5 build over the 2.4.
Posted By: Anonymous

Re: 2013 - 27/12/2012 20:57

Barbz, I think it's time you spilled the beans... wink
Posted By: knight7660

Re: 2013 - 27/12/2012 21:29

whats going on with yours biggenz?

any potential buyers or are you going to keep her? (maybe break the 2.0l bhp record some more)
Posted By: Anonymous

Re: 2013 - 27/12/2012 23:45

Quote:
whats going on with yours biggenz?

any potential buyers or are you going to keep her? (maybe break the 2.0l bhp record some more)

I wish he does keep it. wink


It only needs 2 performance enhancing products to push it to 600hp comfortably. cool

Over two years of pushing the tuning boundaries further than ever, we've removed a major weakest link in the chain , so onwards and upwards for the coming year. wink

Posted By: Anonymous

Re: 2013 - 27/12/2012 23:59

Well one weakest link in Biggenz's car which is probably the biggest is:-











The ladyboy driving it laugh
Posted By: Anonymous

Re: 2013 - 28/12/2012 09:47

Originally Posted By: knight7660
whats going on with yours biggenz?

any potential buyers or are you going to keep her? (maybe break the 2.0l bhp record some more)


I've taken it off the road but will be driving it again when it gets a bit warmer. I do miss driving it so I'm glad no one's bought it. The only problem is I will probably keep spending money on it which is a bad thing! laugh
Posted By: Anonymous

Re: 2013 - 28/12/2012 11:25

Quote:
The only problem is I will probably keep spending money on it which is a bad thing!


Enjoy it, rather then give your money away to the Banksters.

Truly a special coupe. cool
Posted By: Anonymous

Re: 2013 - 28/12/2012 12:55

Originally Posted By: Biggenz
Barbz, I think it's time you spilled the beans... wink


I think so to Barbz
Posted By: Anonymous

Re: 2013 - 28/12/2012 19:19

Originally Posted By: gscozzari
Originally Posted By: Biggenz
Barbz, I think it's time you spilled the beans... wink


I think so to Barbz


Yeah come on Barbz no ones seen your graphs yet even behind closed doors.
Maybe your making it up ???? laugh (rumours start that way )
Posted By: Anonymous

Re: 2013 - 28/12/2012 21:13

Calm down lads! laugh

A very unique platform is being born so needs TLC. wink

Blew my gearbox to bits in two days of getting it back from mapper (thats with boost turned down to 1.6bar). crazy
Quote:
Maybe your making it up ????

Maybe hard working, enthusiastic, but not in the business of fabricating figures my friend. frown
Quote:
Yeah come on Barbz no ones seen your graphs yet even behind closed doors

All will be revealed very soon. thumb
Posted By: Anonymous

Re: 2013 - 28/12/2012 21:52

[quote=Barbz]
Blew my gearbox to bits in two days of getting it back from mapper (thats with boost turned down to 1.6bar). crazy
[quote]

jeez dude another one! you should change your avatar to "strikes terror in the hearts of gearboxes".......
Posted By: Anonymous

Re: 2013 - 28/12/2012 22:06

Ok I believe you and whatever you do has to work laugh

Won't be long until your new chocolate box goes bang as you couldn't be bothered to fit the terror proof box I spent days building by aaaaaaand with a proper proper sweet spot.
You'll love the gearing.

Your always changing things Barbz.
Posted By: Anonymous

Re: 2013 - 28/12/2012 22:51

automatic box, Barbz wink
Posted By: Anonymous

Re: 2013 - 28/12/2012 23:40

One of these boxes would do nicely at £7k a go.
http://www.youtube.com/watch?v=fhPnwIe7yfk
Posted By: Anonymous

Re: 2013 - 30/12/2012 14:02

Originally Posted By: Barbz
One of these boxes would do nicely at £7k a go.
http://www.youtube.com/watch?v=fhPnwIe7yfk


would never handle the torque.
Posted By: Anonymous

Re: 2013 - 30/12/2012 22:58

Be suicidal if you blew up a 7k box.
Posted By: Anonymous

Re: 2013 - 31/12/2012 07:36

Originally Posted By: johnnybravoturbo
Be suicidal if you blew up a 7k box.


You say that, but it's only us coupe owners who think it's expensive when we have to pay a few hundred quid to replace a gearbox. tongue
Posted By: Anonymous

Re: 2013 - 31/12/2012 09:29

Originally Posted By: Biggenz
Originally Posted By: johnnybravoturbo
Be suicidal if you blew up a 7k box.


You say that, but it's only us coupe owners who think it's expensive when we have to pay a few hundred quid to replace a gearbox. tongue


At 7k they have a point laugh
Posted By: Anonymous

Re: 2013 - 31/12/2012 16:50

I think enough of us have blown up engines not far short of £7k?
Posted By: Anonymous

Re: 2013 - 31/12/2012 18:39

Originally Posted By: nyssa7
I think enough of us have blown up engines not far short of £7k?

JBT=3 cry cry cry
Posted By: Anonymous

Re: 2013 - 01/01/2013 00:32

Bit ahead of you :-|
Posted By: Anonymous

Re: 2013 - 01/01/2013 13:58

You can stay there fella I'm happy with that thumb
Posted By: Anonymous

Re: 2013 - 02/01/2013 17:12

surely there must be a sensible priced stroker kit as 400cc per cylinder is a weak base from which to get power unless you are hunting a revvy engine, unsuited to everyday driving?

If sufficient interest was available and a suitable stroker kit could be compiled at favourable terms and a specialist could treat the job as a stack em hi and price em low part of their business to do conversions in any 'free time' / sub con it ..then wouldnt say 500 cc / cylinder (assuming practical with std bore) provide better drivable power, especially low rev torque response for easy overtaking - whilst maintaining safer boost levels on a smaller more responsive turbo - Also help maintain performance off boost, giving more efficient economy with everyday driving.

I am sure on boost power would not disappoint, even with modest breathing enhancements smile

I appreciate I talk from the position of a complete novice, however I would be interested to hear from those involved in performance engineering, particularly those abroad who may have better access to sensibly priced components / machining - custom crank + aftermarket rods do the job? - Rods neednt be too long as cr could no doubt be dropped a little due to capacity compensating off boost and adequate boost applied to make use of lower cr on boost (again lower cr off boost enhancing economy further?)

All very theoretical as I know nothing about the intricacies of perf tuning but very keen to see if above has any mileage if sufficient interest - eg cost of initial custom crank shared out across say ten customers placing deposits, with cheaper re-order pricing offsetting need for orders of tens - with modern CNC machining a small engineering co. would probably be happy with twos subsequently with parameters stored and unit tested.

More thoughts along these lines / above would be useful as not everyone wants to chase megahorses at considerable cost with road unfriendly characteristics.

I guess most would be happy with say c 390 bhp and wide powerband with near max torque other std components can take (excl clutch) available from say 2.5-6k - incidentally what are the limiting areas for say 310-360 lb ft and can any be addressed cheaply when above work carried out?

OK, I shall stop waffling now...
Posted By: Anonymous

Re: 2013 - 02/01/2013 19:47

Originally Posted By: griffster
I guess most would be happy with say c 390 bhp and wide powerband with near max torque other std components can take (excl clutch) available from say 2.5-6k - incidentally what are the limiting areas for say 310-360 lb ft and can any be addressed cheaply when above work carried out?

OK, I shall stop waffling now...


No need for a stroker kit to achieve that

Name me any engine where you can get a stroker kit cheap - except maybe the Beetle which being air cooled doesn't really count (less complex)

Thing is, if you have a crank with a larger stroke, you need shorter rods. Cranks are expensive to make, especially if you have to design and make the tooling as well, so the Stilo/kappa 2.4 crank (as in "here's one Fiat prepared earlier" gets used. Still costs silly money for custom rods - and even thjough we use 5 at a time, the market isn't going to get past 20 sets (which again in terms of recouping tooling costs is nothing)
Much of the exense for most who can't do it themselves, is the labour for the engine rebuild, so might as well go forged for what little extra it costs
And you won't take any advantage of the extra capacity running everyelse (injectors/turbo/ecu especially) as stock - so another byundle of money needed
Which is why those of us who have gone to 2.4/2.5 are still few and far between and have invested far more than we want to own up to

Just my thoughts - if we all drove round in something properly common, like a Fiesta, there might be a market for something, but when did you last see a Coupe that wasn't yours? These days Astom Martins are more common spot
Posted By: Anonymous

Re: 2013 - 03/01/2013 10:56

It's a nice idea but as mentioned the likely hood of getting the numbers together to make a big enough purchase would be a struggle.
If, and it's a big IF, there was as many as 10 sets the price I'm sure could be got considerably cheaper. I'll recklessly throw a number out of £2000 region for custom crank, rods and pistons. These would be for top quality parts and no messing about with unknown materials and manufacturers, you could get creative and make a special setup. You could sell your soul to china for a fair amount less but not a great idea IMO. You'd need full payment for all products ordered, no room for sitting on the fence in that type of a group buy.

Unless your into a dedicated build (more money than just a crank setup) I'd believe the best improvement would be seen in the intake system (one part upgraded means the rest need it to achieve the potential).
Posted By: Anonymous

Re: 2013 - 04/01/2013 09:57

I suspect most people wouldn't consider £2k as "cheap", and you'd still need to factor in as least as much again in ancilliary bits to take advantage
Posted By: Anonymous

Re: 2013 - 04/01/2013 10:42

laugh £2k isn't what some people would consider cheap but they might well be the same people who haven't bought parts for an engine build of ambition. It'd be a struggle to buy standard parts for much less I suspect. I don't mind paying strong money for stuff as long as I'm getting what I consider to be real quality and enhancing features, source them personally and sometimes the price is pretty good. I don't think we'll find anyone with an upgraded engine build who hasn't sunk more money than they first thought they would, it's an expensive task no matter how you do it.
Posted By: Anonymous

Re: 2013 - 04/01/2013 18:19

The gist of the thread I originally responded to was bemoaning the lack of a cheap option

Think I've spent more than enough money destruction testing Coupe engines to be very au fait with prices :-(
Posted By: Nigel

Re: 2013 - 04/01/2013 20:53

The thing is - you don't need a stroker kit to get a reliable 400bhp with a half-decent power band.

With the right turbo, you can get boost from 3,000 rpm all the way to 7,000+

yes - the 2.4 engines are producing monster bhp, but unless you're looking for 500+ bhp, there's just no need (unless you're also looking for other characteristics, such as better off-boost driving, or even earlier spoolup)
Posted By: Anonymous

Re: 2013 - 06/01/2013 17:46

most wont need over 400 bhp, however if the engine is coming apart to strengthen for 350 + bhp, perhaps the hi-cap crank and rods, if inexpensive enough could provider a nicer torque band and less gutless off boost driving? - Again, personally it is much more useful for road driving to extend the power / torque band down 500 rpm at lower end than up 1000 at the upper?
Posted By: Anonymous

Re: 2013 - 06/01/2013 18:27


The lower rpm performance can be worked on and improved without going to a larger stroke. Cr, improved breathing on either side of the cylinder, turbo's, camshafts would be as big an influence. Build it right and there'll be no worries about the lower rpm I believe
Stroke to the bigger capacity and get other areas wrong and you'll not see the benifit, you still have to fill the cylinder no matter how big it is, need to empty it too....
It's not a bad thing a bigger capacity but I'd say it's just a small part of a bigger picture that can easily be hindered by components that have nothing to do with capacity, don't ignore the whole.
Posted By: kj16v

Re: 2013 - 06/01/2013 22:24

^^ yes ^^

Cam choice and timing in particular has a HUGE influence on size and breadth of the power band. I think people in turbo circles often tend to get all hooked up on what turbocharger to buy and completely forget about cams. To me camshafts are the heart of an engine - and even more so on a turbo car. You can build the sweetest spec'd engine ever but get the cams wrong, or don't spend time fine-tuning the cam timing to match the engine -and the driving style- and you'll end up with an car that's just 'not quite as good as it coulda/shoulda been'. That goes for any engine - no matter what the cubes.
Posted By: Anonymous

Re: 2013 - 06/01/2013 22:32

Originally Posted By: kj16v
^^ yes ^^

Cam choice and timing in particular has a HUGE influence on size and breadth of the power band. I think people in turbo circles often tend to get all hooked up on what turbocharger to buy and completely forget about cams. To me camshafts are the heart of an engine - and even more so on a turbo car. You can build the sweetest spec'd engine ever but get the cams wrong, or don't spend time fine-tuning the cam timing to match the engine -and the driving style- and you'll end up with an car that's just 'not quite as good as it coulda/shoulda been'. That goes for any engine - no matter what the cubes.


Proper proper.
Posted By: Anonymous

Re: 2013 - 07/01/2013 08:21


I believe it's important to lay out the targeted power/rpm and gather as much flowbench data as possible and hand this over to a trusted cam designer to grind what he is qualified to design (guy's that can do whole engines including camshaft design are very few in number, it's a specialist field). It's all too easy to have duplicate/generic camshafts that have no sympathy for the finer details an individual engine has. Even small changes on either side of the cylinder make for big differences in recorded infomation and the valve event can be tailored to complement ....


Originally Posted By: kj16v
^^ yes ^^

Cam choice and timing in particular has a HUGE influence on size and breadth of the power band. I think people in turbo circles often tend to get all hooked up on what turbocharger to buy and completely forget about cams. To me camshafts are the heart of an engine - and even more so on a turbo car. You can build the sweetest spec'd engine ever but get the cams wrong, or don't spend time fine-tuning the cam timing to match the engine -and the driving style- and you'll end up with an car that's just 'not quite as good as it coulda/shoulda been'. That goes for any engine - no matter what the cubes.
Posted By: Anonymous

Re: 2013 - 07/01/2013 11:11

call me naive, but if cams can give a much broader power band in a stroke (scuse pun) then wouldnt every engine have a 2-7k power band for sporty road use? - As I understand it the profile/ overlap /duration etc mainly moves the powerband around in orchestra with valve / head and breathing design synced to timing?

eg this, put crudely typically results in pushing power band up rev band if hunting bhp and down if searching torque? - I dont see you appreciably expanding 'power' band and raising all - the black art of profiling / timing / breathing clearly brings some improvements in all areas through greater efficiency however, keeping capacity std (and for simplicity the turbo out of the equation) can you really re-profile to bring far greater power in at 2.5k whilst also giving free breathing and sensible improvements at upper rev end (under 7k)

Wouldnt a modern efficient quick spool low boost turbo linked to a 2.5 and modestly worked over head give far more pleasing results for road use - ie not having to drop two gears and re-spool for those rare brief overtaking opportunities on the narrow twisties?

Merely forwarding a possible tuning pathway for conjecture / debate not to be argumentative, as I mentioned I know nothing about engine design, but happy to explore different avenues if it opens up improved road performance for more individuals perhaps already faced with a re-build & turbo upgrade...
Posted By: Anonymous

Re: 2013 - 07/01/2013 11:55

Sure, improving breathing in the intake and exhaust is the best route. As you say, the cams move the power band about (duration does anyway) and you can't have it all ways but that's not to say you can't improve lower rpm performance on an engine that has a cam that can breath at higher rpm too. Getting the air velocity in the inlet ports to a decent level at lower rpm will help a lot, grind out ports too big or bad shape and you'll need to wait longer for the main event. It's no single component that will make a great engine, it's the sum total of the whole that matters and tayloring it to suit your expectations/ambition, the valve event plays a big part in that, more so than capacity I believe. You could have a 2.5 and louse up the cylinder head, manifolds or systems leading too and from them or fit crazy big cams and you still have a lag laden engine. It's a good idea IF you achieve the balance.

I know next to nothing about the parts available for the 20vt, is there much in the way of choice when it comes to cams? Or is it just a select few profiles that are available? That was the problem with the 16v engine I like and why I scoured the earth for cam cores to grind bespoke.
Posted By: kj16v

Re: 2013 - 07/01/2013 21:41

Griffster:
In addition to the above: Cam timing also has a huge effect on when the turbo spools and how much torque is made when it does spool.

As an example, check out the little writeup I did on the my findings on the effect of timing on torque & power (bottom of the page). Note that it's exactly the same setup, exactly the same boost, the only thing that changes is the cam timing. Pretty significant as you'll see.

I should add that in the end I chose timing somwhere between that of runs 3 and 4, on that setup.

http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=1191994

So my hope for 2013 is that people will start thinking about their engines as a whole, instead of just getting hooked up on turbochargers and boost.

Sometimes it can be very difficult to get through to some folks that, just having some nice forged pistons and a big turbo does not automatically mean that their engine will make a bajillion bhp. Sure, these are important, but they're just 2 parts in a system. Without all parts working together, complimenting each other all you can hope for is disapointment - whether it's 2 litres or 2.5 litres laugh

iNRO:
Pretty much the same selection as the 16VT, so it seems - C&B and Cat Cams. Personally I've never really been impressed by C&Bs on the 16VTs I've seen or tuned - Perhaps they were just bad examples; others not custom timed and the one's I tuned were Race Min on a road car - definitely not a good road setup!

Anyway, I'm going to be stocking Cat Cams for 20VTs and 16VTs.

BTW did you ever find 16VT cores? I just happened to also have done some searching for the same a few months ago and it seems they don't exist, so all 16VT cams have to come from blanks - hence the high price relative to other makes.
Posted By: Anonymous

Re: 2013 - 11/01/2013 10:54

so, what your saying is, apply a little voodoo?! smile

Yes, I see how profile and timing can feed more air to turbo earlier and encourage it to spool earlier - I reckon closer to 2.5k rpm for road use would make a big difference to road driving - the number of times we run sustained rpm over 5.5k on road is clearly minimal by comparison - I dont want an engine to choke up before 6 pref 6.5, however the usable power band needs to be focussed 2.5 to 5.5k?
Posted By: Begbie

Re: 2013 - 11/01/2013 11:20

Originally Posted By: griffster
so, what your saying is, apply a little voodoo?! smile

Yes, I see how profile and timing can feed more air to turbo earlier and encourage it to spool earlier - I reckon closer to 2.5k rpm for road use would make a big difference to road driving - the number of times we run sustained rpm over 5.5k on road is clearly minimal by comparison - I dont want an engine to choke up before 6 pref 6.5, however the usable power band needs to be focussed 2.5 to 5.5k?

So, that is pretty much what a standard 20vt does for it's powerband smile
Posted By: Anonymous

Re: 2013 - 11/01/2013 19:31

Originally Posted By: Begbie
Originally Posted By: griffster
so, what your saying is, apply a little voodoo?! smile

Yes, I see how profile and timing can feed more air to turbo earlier and encourage it to spool earlier - I reckon closer to 2.5k rpm for road use would make a big difference to road driving - the number of times we run sustained rpm over 5.5k on road is clearly minimal by comparison - I dont want an engine to choke up before 6 pref 6.5, however the usable power band needs to be focussed 2.5 to 5.5k?

So, that is pretty much what a standard 20vt does for it's powerband smile


In which case, stick to standard cam timing - just with more boost, some headwork and inlet/exhaust work if required.
Posted By: Anonymous

Re: 2013 - 11/01/2013 23:09

having only driven one modified example I assumed 3k was full boost onset with a turbo upgrade - can you get full boost from 2.5k with say a 310 lb ft and 350bhp envelope?
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