Technical 999cc Engine Tuning, Can you help!?

[EssexUno]

Hello,

I'm really interested in modifying my 999cc engine, what i was thinking initially was just to stick a Punto 75 cam in, but reading through some posts i think someone said you can put a 1.2 8v head on to a 999cc block.

I understand how that will aid in performance boosting because 1.2 head will have bigger valves so more fuel in and more exhaust gas out etc... but my main concern is that if i get a 1.2 (1242cc is that the one??) 8v head what head gasket do i use? Do i use the 999cc gasket (New one of course) or di i use a 1.2 8v head gasket?

I have a MK2 Fiat uno 5dr 999cc SPI and i just want a bit more power from it.

In a post that Smokeme wrote he said that fitting a Punto 75 cam will increase the BHP by 15 (think he said 8-15 so dunno but still an increase).

So basically if i get a 1.2 8v head and replace my head with that will i only need to bolt up the exhaust and inlet manifolds back on and time it up? And i have also read that if you put a 1242 engine in that you will need a spacer to the exhaust manifold because the body is taller but as i'm only wanting to change the head than do i need to do any modifications to the exhaust?

I'm coming to the end on a 2 year level 3 mechanics course so i can do all of this but just need a bit of info before i rip apart my daily driver lol.


Sorry for the essay lol just trying to give you as much information i can about mt understanding of the job

Thanks to anyone who can shed some light on this matter lol

Dan

 

[EssexUno]

Hello, seeing that no-one replied to my thread i'm just informing people that i should be getting a punto 75 head with the 866 camshaft. I will be fitting the camshaft into my 999cc mk2 uno but i would like to know something.

Will i be able to fit the shims from the punto 75 head into the uno head so that the valve clearences are right and so that i don't have to muk about measuring and changing them about etc...

or are the shims in the punto 75 head bigger than the standard uno shims?

I want to be able to fit the camshaft the day i recieve it and don't know if i need to order new shims or if i can just use the 75 shims if they are already the right clearence. And does anyone have the correct clearances i need for the punto 75 cam as i guess there not going to be the same as the 999cc standard cam.

Thanks
Dan

 

[randomspeedfreak]

dont know enough about these engines sorry

im sure the cinq/sei section will be of help to you

 

[EssexUno]

Hi people, i have a punto 75 (Punto SX) cylinder head complete with an 866 cam and injectors, i am going to fit the 866 cam to my uno 999cc this weekend. Hopefully everything will go fine, I'm also replacing the timing belt as i don't know when this was last done and I have a new rocker cover gasket. :slayer:

Hope i have the punto 75 valve clearances right. Is it 0.40 +/- 0.5 Inlet and 0.45 +/- 0.5 exhaust?

Cheers
Dan

 

[alexGS]

Yes, those clearances will be fine, but I think that you will need at least some replacement shims to get them right, so I don't think you'll be up and running straight away But I could be wrong I guess it depends on how accurately those cams are machined, and given that you're not lapping-in the valves, maybe you'll get away with it.

Have you done a top speed measurement not that I would condone such a thing, but the difference from your tuning should be obvious afterwards by repeating the test in the same conditions...

-Alex

 

[EssexUno]

Thanks Alex GS,

I was asking my tutor today about doing the cam next friday (lesson in workshop) and he said yes, i measured all the shims in the punto 75 head, two were missing the measurement on the back but i used a micrometer and got the size in mm. We have a rolling road in the workshop so i could ask if i can use that but i don't know if we will have time because my lesson is only about 4 or 5 hours.

In my engine 999cc FIRE engine do the valves go

Cylinder 1 Cylinder 2 Cylinder 3 Cylinder 4
Valves Valves Valves Valves
(inlet)(exhaust) (inlet)(exhaust) (exhaust)(inlet) (exhaust)(inlet)

Because thats how it was in the punto 75 cylinder head?

Thanks

Dan

 

[alexGS]

Yes - all engines in the FIRE family (and actually, all other four-cylinder FIAT engines that I can think of) have the valves in that order. It's obviously something you have to pay attention to when checking the clearances.

-Alex

 

[shadowmk42]

hi ya yes you can put a 1.2 head on it and put the 999cc head gasket back on but try it againt the head 1st 2 make sure it will clear the ports and the exhaust problem put a 1.2 exhaust on it but 2 make it quicker put fast road cams in it, four branch manifold, de-cat, induction kit that should give it a few more bhp but get the rev limiter taken out aswelli have a vauxhall nova we have put a 1.4 bottom end with a 1.6 head nd u have 2 change gear just b4 the rev counter goes back to 0 i no it aint a uno but im lookin on here 2 see how i can put a 2.0 turbo coupe engine in one

but try that it will work im a mechanic been fixing cars along time

 

[alexbpl]

I have a 999cc FIRE engine in my panda.

What modifications did you end up doing to your 999cc UNO?

They will also work to upgrade mine too!!

Thanks,

Alex

 

[EssexUno]

I didn't really do much in the end, i replaced the headgasket not too long after i posted the last post and when i was doing the headgasket i fitted a punto 74 866 camshaft. it raised the top end a bit and made the engine breath a bit easier.

i've also removed my silencer as it was blowing and fitted a backbox.

I'm not going to bother with any more mods to the 999cc as i have bought a 1.2 60s punto engine for £50 and am currently rebuilding this to fit into my uno.

I'm going to lighten the flywheel to make it rev easier and i'm going to lightly port and polish the cylinder head.

Hopefully this helps you?

Dan

 

[rawill]

I'm going to lighten the flywheel to make it rev easier

Dan

Hi Dan, it might make it rev easier, but is there a downside to lightening the flywheel.

 

[jo0lz]

Hi Dan, it might make it rev easier, but is there a downside to lightening the flywheel.

Yeah
Downside is if you take too much weight off your idle gets a bit lumpy