Hi
Back in my mini days a lot of power was released by fitting larger valves in a flowed cylinder head,
I`ve heard that punto 75 heads have bigger valves as standard could these be fitted into an spi head,I know work would have to be done by a cylinder head specialist,
Cheers
Adrian

AIJ29 said:

punto 75 heads have bigger valves as standard

Click to expand...

No, all 8v F.I.R.E. engines exept 770 Panda unit has the same valves. 770 ccm engine from Panda has smaller valves.

Thats interesting i read on another forum that it was pointless fitting a 75 cam because the power difference came from the mpi and the bigger valves in the head?
Cheers
Adrian

Bigger throttle body, warmer cam and bigger ports maybe?

Yaninnya said:

No, all 8v F.I.R.E. engines exept 770 Panda unit has the same valves. 770 ccm engine from Panda has smaller valves.

Click to expand...

If I were the mocking type i would fill an entire post with WRONG

On ALL the Fire engines the intake valves are larger then the exhaust.

The 769cc engine has the smallest valves, then is the 999cc, then the 1108cc/1242cc SPI, then the 1108 MPI then the 1242 MPI then the 1242 MPI 16V.

The Punto 75 is the best flowing head even comparing to the 16V engine.

I have the actual sizes somewhere but i'm not sure on location , i may post it some other day unless someone beats me to it.

Basically it costs more to install larger valves then to swap heads , on a stock engine the valves are oversize already, the 999cc fire has 27mm exhaust and 32mm intake which is much larger then most engines of similar displacement.

There are people making over 140hp NA on the 1.2 with completly stock heads, The new Rally Panda for example comes with 130hp stock with the 1242cc fire 8V

I'm getting a Punto 75 head complete for my 60 engined turbo, you think it's worth swapping the whole head and manifold over or just the cam?

Am also tempted by the 75 head as it's easier to bypass the water heating on the intake manifold - with handy bolt spacing over the water port on no1 cylinder end.

When i got my head proted and polished the company who did it who do alot of work on Cosworth heads and alike said that there would be very little to gain by changing the valve sizes as they were big enough for the displacement, it was only if you were into really serious trackday stuff with it were it woudl have to have an aggresive cam as well making it lumpy on the road, the real gains were to be had be proper gas flowing work.

And as I was prepared to pay for bigger valves he talked himself out of more money, so respect his opinion on that one, coudl have just told me yes and asked for more bucks.

Aaron.

so the best engine to use really is the 75, and just not use all the injectors.. does the SPI unit fit onto the the punto75 inlet manifold ok?

I'd like to just fit the whole 75 head, as it lends itself more to having the water heating taken off the manifold. Reckon there's sod all point in trying to fit an intercooler if I'm heating it all back up further along.

SPI unit will fit, but I understand it's tricky.

fixitagaintomorrow said:

I'd like to just fit the whole 75 head, as it lends itself more to having the water heating taken off the manifold. Reckon there's sod all point in trying to fit an intercooler if I'm heating it all back up further along.

SPI unit will fit, but I understand it's tricky.

Click to expand...

The SPI intake won't fit on the MPI head (punto 75) because the middle studs are much higher up then the SPI one.

I've made a page comparing some stock parts here http://smokeme.coconia.net/parts_info.htm

I'll want some ideas on what else to compare (i have the time/parts now )

So far i only compared heads and cams, i'll be comparing part fitment between engines soon (i'm waiting for a 769cc and a chance to remove the 16V again )

It's the SPI throttle body I was thinking of fitting to the 75's manifold, I'm under the impression it fits ok-ish.

I may even look into redrilling the head for an SPI manifold to fit, will see when I get it. Hopefully the ports will match up!

Hi Pete
I`ve heard of the mpi manifold matching up with the spi throttle body but i think you need a spacer,
Keep us posted
Cheers
Adrian

I've just gone through this very exercise .

The 75 head can't really be redrilled to take the Cinq manifold - there's just not enough metal where you'd need to drill the head .(which is no doubt why Fiat didn't do it themselves)

The 75 TB doesn't have an injector so you have to use the top section of the Cinq TB fitted onto the lower part of the 75's TB . I tried this today and it bolts straight on . However , because of the injector on the Cinq TB , the lower half of the 75 TB needs to be slightly machined to remove a step between the 2 parts and to smooth the air flow down to the butterfly .

If you used the Cinq head & inlet manifold , you could fit the 75 TB , but would have to machine the inlet hole in the Cinq manifold to take the larger TB (otherwise there's no point in fitting a larger diameter TB)

You could just fit the Cinq TB complete onto the 75 inlet , but you'd need the 75's spacer that fits between the TB & the manifold .

John

fixitagaintomorrow said:

I'm getting a Punto 75 head complete for my 60 engined turbo, you think it's worth swapping the whole head and manifold over or just the cam?

Am also tempted by the 75 head as it's easier to bypass the water heating on the intake manifold - with handy bolt spacing over the water port on no1 cylinder end.

Click to expand...

defurnatly get the whole head and inlet manifold...

Reson: The Punto 75 head and inlet has bigger ports than Punto 60. The inlet is the main reason for the different in hp between Punto 60 and Punto 75 engines.
You can for example fit a head from Punto 75 and then block of the injectors and then fit the monopoint on the intake
Should give you 10 hp no problem

fixitagaintomorrow said:

SPI unit will fit, but I understand it's tricky.

Click to expand...

Tricky?? naah - not for a "Tricker"

If you get a 40mm TB from me I can make you a costom spacer and gaskets. Then it would be a complete swap

hang on, let me get this straight.

u could get a 75 head, complete with cam and inlet manifold, then get a 40mm TB made up to fit straight on?

how would u go about blocking up the injectors on the 75 inlet manifold (i am guessing they are there?)

could u just take the old 1108 head out and bolt this one in with no problems?

and would it cause any problems if for example u were plannin on gettin the 1108 unit turbo'd?

Hi Mase
When i had my swift people used to tap a thread into the injector holes and put a bolt in,don`t know if this is possible on the 75 head but i cant see why not
Cheers
Adrian

AIJ - the 75 injectors are in the manifold , not the head . So you can either leave them in place or have the manifold plugged .

Mase - I have all these parts on my garage floor right now in readiness for the 1242 swap and fitting of a 75 head / cam / TB . I've already ascertained that the lower half of the 75 TB will accept the top half of the Cinq TB (with the injector) , but the lower half just needs a bit of machining to line up the 2 sections . The spacer is just the standard 75 spacer between the TB & inlet manifold .As you're not far away , come & take a look sometime before I start if you like - it's much more obvious when you see the parts for real .

John

awesome man, i might just have to take u up on that offer.

how much was the 75 head and inlet manifold in total?

Hi minijohn

The original Punto 75 spacer will be to high and you will not be able to close the bonnet.

theres a post somewhere on fittinf the 75tb nd getting the spacer machined down