Alexis dont get my position on this forum mixed up here.
Im not commenting as a trader im commenting as a customer which im well within my rights to do so.

And my post still stands.

Guy Croft isnt a trader on here,and even if he was theres a disclaimer above each section to say the forum takes no part in issues between the customer and the trader.

As a customer i am hard to please because i expect the service to be on the level or better than my own as im sure Barbz and Flea will varify.

Most people want a result.
They dont care about what goes on in between.

I contradict myself a little bit in regards to Tricky as i do know what went on with my build in depth and asked questions every step of the way.
But posting this on a public forum for the world to see/copy is suicide for any trader whos getting good results consistently.

For me the reason behind this is i had unusual running faults with a previous head.

The difference is i spend until the early hours of most mornings trying to perfect the car and pushing it to way beyond what i was told was ever capable.And im now doing that reliably.

The same unusual faults that a customer of mine has to the point where hes considering selling the car.
This isnt my head or Barbz's but i only name a few of the adverse symptoms that i had with my previous engine,.

The car wasnt nice to drive,in fact it ruined it completly for me.
When i ring anyone,first impressions are crucial.
You develop a professional relationship,friendship and in some cases both.

Lets not forget that 6 years ago when i first joined the forum 300bhp was impossible and making the coupe 20vt labled as a weak engine even with forged internals.


If i dont trust someone or think that everything is too much trouble then i wont use them.
Because lets be right,there not going to deal with things if it goes wrong.

Guy does have a bit of a 'short fuse', but I know where he's coming from it weeds out the non-serious, don't want to learn I just want 10,000 BHP types. But give him a chance he has more knoledge in his little finger that he is willing to share.

Can anyone please post some pictures of 20v ports std or modified ? Then maybe we can talk about something constructive for everyones benifit !

Standard ports look bad (these are from my head)

Modified ports can attach Ferrarist

As much as Nick will hate this, I know of one picture (L to R, 8v, 16v, 20v)



'the', his forum name on here is Barbz

Ggrrrrrr, that's just molds of standard ports like any fool can do, just as well as he's a no more than a fool.

I've a 20vt head sitting on the shelf that doesn't inspire me really but maybe I should drag it out and see what's so bad about it compared to a 16v

Agreed,im sure he knows what hes doing and no trader should be a library of information for freeloaders.

As for porting,what are you trying to achieve and on what budget here?
Also is it for you to try yourself or to get someone to do it for you?

The crucial part of porting is to ensure that the tool you use is a diamond cut piece.
The portings must be even across the board making sure the tool doesnt wear between the ports.
Exhaust porting,matched to head helps but inlet side has currently not been messed with until now.

The inlet area looks large, but it might be the short splitter that makes it look that way, it does'nt pose much of a nozzle to the valve, more just an 'opening' like jap types.

The clue is in the signiture :-) I'm into 16v, but just interested what people are doing on the 20v.

Not sure what part of the exhaust side you mean needs matching to the head ?

FWIW I had the MOST comprehensive if not ONLY detailed mod & test appraisal of the 20v head on my website free for all the world to see for nearly two years, from Feb 09. If you didn't read it or print it off when you had the chance - not my problem.

G

Some of Nik's inlet moulds - with permission.





And exhust side -

Just had a quick look (measure) at the 20v head and without doubt it's lacking from factory in at least one place, what a waste of valve size. Can't say I like the look of the SSR either, at least what I can see of it as the valves are still in the head, there doesn't hardly look to be one!

16v is the daddy :-)

(A bit uncalled for John and not really professional for one trader to be slagging off another business / person)
Alexis dont get my position on this forum mixed up here.
Im not commenting as a trader im commenting as a customer which im well within my rights to do so. And my post still stands...

what the heck is this all about? You're a customer of mine & some grievance? Did I show you the door?! If I did you would have deserved it for sure, I never turned my back on a justifiable complaint.

GC

There's small difference - i have Flea remap, but he carefully encrypted his eProm - no one can read it....
If i had Barbz head on my engine as well - no problem to see his work in details.....no even need to remove the head......



Few days ago i finished my head prep, it took me almost 6-7 summary days to complete.....

I assume this was directed to Johnny? Alexis was merely pointing out that it's not very good forum etiquette to slag other traders off - it tends to come back and bit at some point in the future.

Please don't take any remarks above as an indication that you're not welcome here - as you're well aware, the Coupe 20vt is highly under-developed from a tuning perspective and we need all the help we can get, even if its to inform us of the shortcomings of the engine design (especially if you can tell us there's a solution... )

Yeah, Nigel, it's Johnnybravoturbo.

G

Really??

What is it worth if I reproduce the GC 20v head prep thread? It would take me near 2 days. I don't think I could do it here - you don't have an internal photo hosting facility I think?

GC

Guy, if you wish, send me the photo's and text and I can knock the page up on here

Thanks Alexis, would be better done by me direct, if I do it - how do upload photos? Asked before but forgotten.

If I post I want some things clearly understood/accepted, I'm categorically not going to argue the case for them.

1. The finite limit for port size and for most heads that is based on the metal wall thickness wherever you are working.
2. Flow loss - compared with standard - due to your work - will always generate power loss. This is as true for valve-in flow, bare-port-flow (BPF) inlet and exhaust and manifolding bolt-on loss.
3. The valve-in flow should always end up the same (at max/peak lift - which you have to find for yourself) or less than BPF. The peak lift valve-in loss depends on several factors and often - as is the case with the 20v - it cannot be removed.
4. The controlling section of any 4 valve head layout (excl inlet manifold which may be a controlling section in itself and certainly is on the 20v) is always the splitter region and that is always much smaller than the valve throat.
5. Within the constraint of rule 1 you can go as big as you like on a turbo inlet port and the engine will consequently develop more power/torque (if its turbo is well matched). With very big ports & if the turbo is a poor match the lower torque region will be rather weaker than it should be.
6. Gasflowing/porting/head work (encompassing port mods and valve-seat mods) if done according to rule (2) will always yield same power/torque as before on lower boost - or more power for same boost. Gasflowing always involves metal removal and its purpose is simple - reduction of losses in the airflow.
7. As a rule of thumb 150cfm @ 10" inlet flow can yield over 280bhp on a nominally 2 liter 16v unit in atmo trim and well over 800bhp on a turbocharged unit.
8. There is an empirical ratio of ex-inlet BPF below which you will suffer comparative power loss vs a head with a better ratio and that ratio is about 73% atmo and a higher ratio is definitely better on a turbo unit.
9. Turbo units are critically sensitive to exhaust system layout and cam timing and unless these are optimised for the particular unit you are working on the full potential gains will never be realised. Same is true of charge temperature and calibration and if those things aren't 'right' you won't get gains from the head you'll get detonation.

That's all the rules I can think of right now but I'm sure there are some more.

G

I enter this post as a customer hence my write up.
Anyone else wouldnt have been questioned on such a response.

An hour ago Guy Croft had the balls to ring me up and clear the air ref my complaint.
I am not a customer of his but was disheartened at the responses i got from GC over a period of 3 weeks regarding a potential build.

He appolagised in full for the issues and no hard feelings have been taken on either side.
So rant over,please disregard my previous statement.

Enter the full image URL, and that's it...

but I don't have URLs - all the info is jpegs on my laptop

G

Guy, if you wish, I can host the photo's on photobucket and can send you the links back to you once all uploaded

As Johnny said - I apologised in full for the issues and no hard feelings have been taken on either side. Actually he had the balls to ring me - I got his answering machine!

G

Now this is more like it ! Guy, can you recall the E-I % ratio achevied on the head in question ?

Look are we not all here to make the coop great?

So lets put some differences aside and concentrate on that?

Surely, we are all darn intelligent chaps, some are more specialist than others, so c'mon chaps lets tune the coop.

Reading a bit about valve sizes it seems the 20v has a problem, too small a diameter to begin with and the port not big enough for even the size Fiat provided. A valve more in line with what is deemed suitable would mean breaking through the port wall I suspect.

I'd suggest Fiat thought standard power was all the 20vt should ever do and didn't design in a margin for power hungry petrolheads.

You best free up some space in your wallet then kid
After you Naz.

When/if the original GC thread is re-published, I think it will say that 32mm inlet valves were fitted, that there is plenty of meat in the head for enlarging ports etc and that 137 cfm @ 10" was achieved (valve in) - which considering the engine has five cylinders is good enough for nigh on 300 BHP N/A.

Of course the 16 valve head was designed with serious rally competition in mind (for the Integrale) and the 5 cylinder engine was not designed with any type of competition in mind - as you have observed, the standard inlet valves are small compared with what Mario Illien would advise and hydraulic tappets just don't cut it in competition engines.

It is easier to fill 400cc pots than it is 500cc pots, so I think the 20V head - though not maybe a better design than the 16V head - has every chance to be modified to produce better ultimate power than the 4 pot engine.

According to my notes, the head for the 2.4 litre engine has 33.5mm inlet and 28mm exhaust valves. Unless the casting is radically different, this could be the first step towards a decent upgrade of performance.